Emerging arboviruses and public health challenges in Brazil

OpenAIRE

Lima-Camara,Tamara Nunes

2016-01-01

ABSTRACT Environmental modification by anthropogenic actions, disordered urban growth, globalization of international exchange and climate change are some factors that help the emergence and dissemination of human infectious diseases transmitted by vectors. This review discusses the recent entry of three arboviruses in Brazil: Chikungunya, West Nile, and Zika virus, focusing on the challenges for the Country’s public health. The Brazilian population is exposed to infections caused by th...

[Zika virus: Another emerging arbovirus in Venezuela?].

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Valero Nereida

2015-09-01

Current health conditions of Venezuela, together with the tropical proliferation of different types of Aedes (aegypti and albopictus), suggest the arrival to this country of ZIKA virus (ZIKV). The Pan American Health Organization urges Latin American countries to take measures to prevent the ZIKV entry and advises that these measures must be designed to detect the introduction of ZIKV in an area, track its spread and actively monitor the disease. In Venezuela and other Latin-American countries, where endemicity is high for other arboviruses such as dengue arid chikungunya, health authorities should strengthen their surveillance systems to detect early and timely introduction of ZIKV ap.d refine diagnostic methods to confirm the infection rate; however, the high incidence of cases due those viral agents reflects weakened and poorly timed insensitive monitoring systems, as well as, poor vector control measures, arising the questions: will this arbovirus pop in our country, will it set as the other as edemicepidemic and lead to alter their clinical behavior and severity of the disease?

Comprehensive proteome profiling in Aedes albopictus to decipher Wolbachia-arbovirus interference phenomenon.

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Saucereau, Yoann; Valiente Moro, Claire; Dieryckx, Cindy; Dupuy, Jean-William; Tran, Florence-Hélène; Girard, Vincent; Potier, Patrick; Mavingui, Patrick

2017-08-18

Aedes albopictus is a vector of arboviruses that cause severe diseases in humans such as Chikungunya, Dengue and Zika fevers. The vector competence of Ae. albopictus varies depending on the mosquito population involved and the virus transmitted. Wolbachia infection status in believed to be among key elements that determine viral transmission efficiency. Little is known about the cellular functions mobilized in Ae. albopictus during co-infection by Wolbachia and a given arbovirus. To decipher this tripartite interaction at the molecular level, we performed a proteome analysis in Ae. albopictus C6/36 cells mono-infected by Wolbachia wAlbB strain or Chikungunya virus (CHIKV), and bi-infected. We first confirmed significant inhibition of CHIKV by Wolbachia. Using two-dimensional gel electrophoresis followed by nano liquid chromatography coupled with tandem mass spectrometry, we identified 600 unique differentially expressed proteins mostly related to glycolysis, translation and protein metabolism. Wolbachia infection had greater impact on cellular functions than CHIKV infection, inducing either up or down-regulation of proteins associated with metabolic processes such as glycolysis and ATP metabolism, or structural glycoproteins and capsid proteins in the case of bi-infection with CHIKV. CHIKV infection inhibited expression of proteins linked with the processes of transcription, translation, lipid storage and miRNA pathways. The results of our proteome profiling have provided new insights into the molecular pathways involved in tripartite Ae. albopictus-Wolbachia-CHIKV interaction and may help defining targets for the better implementation of Wolbachia-based strategies for disease transmission control.

The Role of Interferon Antagonist, Non-Structural Proteins in the Pathogenesis and Emergence of Arboviruses

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Samantha S. Soldan

2011-06-01

Full Text Available A myriad of factors favor the emergence and re-emergence of arthropod-borne viruses (arboviruses, including migration, climate change, intensified livestock production, an increasing volume of international trade and transportation, and changes to ecosystems (e.g., deforestation and loss of biodiversity. Consequently, arboviruses are distributed worldwide and represent over 30% of all emerging infectious diseases identified in the past decade. Although some arboviral infections go undetected or are associated with mild, flu-like symptoms, many are important human and veterinary pathogens causing serious illnesses such as arthritis, gastroenteritis, encephalitis and hemorrhagic fever and devastating economic loss as a consequence of lost productivity and high mortality rates among livestock. One of the most consistent molecular features of emerging arboviruses, in addition to their near exclusive use of RNA genomes, is the inclusion of viral, non-structural proteins that act as interferon antagonists. In this review, we describe these interferon antagonists and common strategies that arboviruses use to counter the host innate immune response. In addition, we discuss the complex interplay between host factors and viral determinants that are associated with virus emergence and re-emergence, and identify potential targets for vaccine and anti-viral therapies.

Vertebrate Reservoirs of Arboviruses: Myth, Synonym of Amplifier, or Reality?

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Goro Kuno

2017-07-01

Full Text Available The rapid succession of the pandemic of arbovirus diseases, such as dengue, West Nile fever, chikungunya, and Zika fever, has intensified research on these and other arbovirus diseases worldwide. Investigating the unique mode of vector-borne transmission requires a clear understanding of the roles of vertebrates. One major obstacle to this understanding is the ambiguity of the arbovirus definition originally established by the World Health Organization. The paucity of pertinent information on arbovirus transmission at the time contributed to the notion that vertebrates played the role of reservoir in the arbovirus transmission cycle. Because this notion is a salient feature of the arbovirus definition, it is important to reexamine its validity. This review addresses controversial issues concerning vertebrate reservoirs and their role in arbovirus persistence in nature, examines the genesis of the problem from a historical perspective, discusses various unresolved issues from multiple points of view, assesses the present status of the notion in light of current knowledge, and provides options for a solution to resolve the issue.

Vertebrate Reservoirs of Arboviruses: Myth, Synonym of Amplifier, or Reality?

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Kuno, Goro; Mackenzie, John S; Junglen, Sandra; Hubálek, Zdeněk; Plyusnin, Alexander; Gubler, Duane J

2017-07-13

The rapid succession of the pandemic of arbovirus diseases, such as dengue, West Nile fever, chikungunya, and Zika fever, has intensified research on these and other arbovirus diseases worldwide. Investigating the unique mode of vector-borne transmission requires a clear understanding of the roles of vertebrates. One major obstacle to this understanding is the ambiguity of the arbovirus definition originally established by the World Health Organization. The paucity of pertinent information on arbovirus transmission at the time contributed to the notion that vertebrates played the role of reservoir in the arbovirus transmission cycle. Because this notion is a salient feature of the arbovirus definition, it is important to reexamine its validity. This review addresses controversial issues concerning vertebrate reservoirs and their role in arbovirus persistence in nature, examines the genesis of the problem from a historical perspective, discusses various unresolved issues from multiple points of view, assesses the present status of the notion in light of current knowledge, and provides options for a solution to resolve the issue.

Neglected Australian Arboviruses and Undifferentiated Febrile Illness: Addressing Public Health Challenges Arising From the 'Developing Northern Australia' Government Policy.

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Gyawali, Narayan; Bradbury, Richard S; Aaskov, John G; Taylor-Robinson, Andrew W

2017-01-01

The Australian Government is currently promoting the development of Northern Australia, with an associated increase in the local population. Consequent to this is the public health threat posed by heightened human exposure to many previously neglected arboviruses that are indigenous to the region. This initiative to support economic activity in the tropical north of the continent is leading to the accelerated expansion of an infection-naïve human population into hitherto un-encountered ecosystems inhabited by reservoir animals and vectors for these arboviruses. Combined with an apparent rise in the number and impact of dramatic climate events, such as tropical cyclones and floods caused by torrential monsoonal rainfall, this heightens the potential for viral transmission to humans. More than 75 arboviruses have been identified in Australia, some of which are associated with human disease but for which routine tests are not available to diagnose infection. Here, we describe briefly the neglected Australian arboviruses that are most likely to emerge as significant agents of human disease in the coming decades. We also advocate the establishment of a thorough surveillance and diagnostic protocol, including developing new pan-viral rapid tests for primary care use to assist in the early diagnosis and correct treatment of affected patients. We propose that the implementation of these activities will enhance our understanding of the geographical range, prevalence, identification and control of neglected Australian arboviruses. This would minimise and limit the possibility of large-scale outbreaks with these agents as population and economic growth expands further into Australia's tropical north.

Enhanced arbovirus surveillance with deep sequencing: Identification of novel rhabdoviruses and bunyaviruses in Australian mosquitoes.

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Coffey, Lark L; Page, Brady L; Greninger, Alexander L; Herring, Belinda L; Russell, Richard C; Doggett, Stephen L; Haniotis, John; Wang, Chunlin; Deng, Xutao; Delwart, Eric L

2014-01-05

Viral metagenomics characterizes known and identifies unknown viruses based on sequence similarities to any previously sequenced viral genomes. A metagenomics approach was used to identify virus sequences in Australian mosquitoes causing cytopathic effects in inoculated mammalian cell cultures. Sequence comparisons revealed strains of Liao Ning virus (Reovirus, Seadornavirus), previously detected only in China, livestock-infecting Stretch Lagoon virus (Reovirus, Orbivirus), two novel dimarhabdoviruses, named Beaumont and North Creek viruses, and two novel orthobunyaviruses, named Murrumbidgee and Salt Ash viruses. The novel virus proteomes diverged by ≥ 50% relative to their closest previously genetically characterized viral relatives. Deep sequencing also generated genomes of Warrego and Wallal viruses, orbiviruses linked to kangaroo blindness, whose genomes had not been fully characterized. This study highlights viral metagenomics in concert with traditional arbovirus surveillance to characterize known and new arboviruses in field-collected mosquitoes. Follow-up epidemiological studies are required to determine whether the novel viruses infect humans. © 2013 Elsevier Inc. All rights reserved.

The Insect Microbiome Modulates Vector Competence for Arboviruses

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Natapong Jupatanakul

2014-11-01

Full Text Available Diseases caused by arthropod-borne viruses (arboviruses, such as Dengue, West Nile, and Chikungunya, constitute a major global health burden and are increasing in incidence and geographic range. The natural microbiota of insect vectors influences various aspects of host biology, such as nutrition, reproduction, metabolism, and immunity, and recent studies have highlighted the ability of insect-associated bacteria to reduce vector competence for arboviruses and other pathogens. This reduction can occur through mechanisms, such as immune response activation, resource competition, or the production of anti-viral molecules. Studying the interactions between insect vectors and their microbiota is an important step toward developing alternative strategies for arbovirus transmission control.

Nature, nurture and evolution of intra-species variation in mosquito arbovirus transmission competence.

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Tabachnick, Walter J

2013-01-11

Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses). Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature) and environmental (nurture) factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission.

Nature, Nurture and Evolution of Intra-Species Variation in Mosquito Arbovirus Transmission Competence

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Walter J. Tabachnick

2013-01-01

Full Text Available Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses. Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature and environmental (nurture factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission.

Nature, Nurture and Evolution of Intra-Species Variation in Mosquito Arbovirus Transmission Competence

Science.gov (United States)

Tabachnick, Walter J.

2013-01-01

Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses). Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature) and environmental (nurture) factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission. PMID:23343982

The Role of RNA Interference (RNAi in Arbovirus-Vector Interactions

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Carol D. Blair

2015-02-01

Full Text Available RNA interference (RNAi was shown over 18 years ago to be a mechanism by which arbovirus replication and transmission could be controlled in arthropod vectors. During the intervening period, research on RNAi has defined many of the components and mechanisms of this antiviral pathway in arthropods, yet a number of unexplored questions remain. RNAi refers to RNA-mediated regulation of gene expression. Originally, the term described silencing of endogenous genes by introduction of exogenous double-stranded (dsRNA with the same sequence as the gene to be silenced. Further research has shown that RNAi comprises three gene regulation pathways that are mediated by small RNAs: the small interfering (siRNA, micro (miRNA, and Piwi-interacting (piRNA pathways. The exogenous (exo-siRNA pathway is now recognized as a major antiviral innate immune response of arthropods. More recent studies suggest that the piRNA and miRNA pathways might also have important roles in arbovirus-vector interactions. This review will focus on current knowledge of the role of the exo-siRNA pathway as an arthropod vector antiviral response and on emerging research into vector piRNA and miRNA pathway modulation of arbovirus-vector interactions. Although it is assumed that arboviruses must evade the vector’s antiviral RNAi response in order to maintain their natural transmission cycles, the strategies by which this is accomplished are not well defined. RNAi is also an important tool for arthropod gene knock-down in functional genomics studies and in development of arbovirus-resistant mosquito populations. Possible arbovirus strategies for evasion of RNAi and applications of RNAi in functional genomics analysis and arbovirus transmission control will also be reviewed.

Nature, Nurture and Evolution of Intra-Species Variation in Mosquito Arbovirus Transmission Competence

OpenAIRE

Tabachnick, Walter J.

2013-01-01

Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses). Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature) and environmental (nurture) factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that compris...

Emerging arboviruses and public health challenges in Brazil.

Science.gov (United States)

Lima-Camara, Tamara Nunes

2016-06-27

Environmental modification by anthropogenic actions, disordered urban growth, globalization of international exchange and climate change are some factors that help the emergence and dissemination of human infectious diseases transmitted by vectors. This review discusses the recent entry of three arboviruses in Brazil: Chikungunya, West Nile, and Zika virus, focusing on the challenges for the Country's public health. The Brazilian population is exposed to infections caused by these three arboviruses widely distributed on the national territory and associated with humans. Without effective vaccine and specific treatment, the maintainance and integration of a continuos entomological and epidemiological surveillance are important so we can set methods to control and prevent these arboviruses in the Country. RESUMO A modificação do ambiente por ações antrópicas, o crescimento urbano desordenado, o processo de globalização do intercâmbio internacional e as mudanças climáticas são alguns fatores que vêm facilitando a emergência e disseminação de doenças infecciosas humanas transmitidas por vetores. Este comentário aborda a recente entrada de três arbovírus no Brasil, Chikungunya (CHIKV), West Nile (WNV) e Zika (ZIKV), com enfoque nos desafios para a Saúde Pública do País. Transmitidos por mosquitos vetores amplamente distribuídos no território nacional e associados ao homem, a população brasileira encontra-se exposta à infecção por esses três arbovírus. Na ausência de vacina eficaz e tratamento específico, são importantes a manutenção e integração de uma vigilância entomológica e epidemiológica contínua, a fim de direcionarmos métodos de controle e prevenção contra essas arboviroses no País.

Factors contributing to and strategies to combat emerging arboviruses.

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Callender, David Michael

2018-04-17

Less than half a century ago infectious diseases appeared to be destined to be extinguished via as a culmination of medical triumphs. As focus turned towards combating non-communicable diseases, emerging and re-emerging diseases (EIDs) have bloomed from those ashes. Five epidemic mosquito-borne arboviruses (Yellow Fever virus (YFV), Dengue virus, West Nile virus, Chikungunya virus, and Zika virus) have emerged in the recent past. Arboviruses are of the utmost importance with respect to EIDs due to intensive growth of globalisation, arthropod urban fitness/adaption, and environmental changes. We focus on recent outbreaks of the arthropod borne viruses (arboviruses) Zika virus and YFV. Factors contributing to the blossoming of EIDs (environmental, globalisation, and urbanisation) and combating strategies (surveillance, containment, and prevention) will be discussed. Specifically, Zika virus and YFV will be used in the context of these factors and strategies. YFV is discussed in detail as it pertains to these factors and strategies in the United States (US), 2017 Brazil Outbreak, 2016 Africa Outbreak, and global risk. Vigilance is needed to focus on, prevent, and control the current and next arbovirus EIDs.

Genome Investigations of Vector Competence in Aedes aegypti to Inform Novel Arbovirus Disease Control Approaches

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David W. Severson

2016-10-01

Full Text Available Dengue (DENV, yellow fever, chikungunya, and Zika virus transmission to humans by a mosquito host is confounded by both intrinsic and extrinsic variables. Besides virulence factors of the individual arboviruses, likelihood of virus transmission is subject to variability in the genome of the primary mosquito vector, Aedes aegypti. The “vectorial capacity” of A. aegypti varies depending upon its density, biting rate, and survival rate, as well as its intrinsic ability to acquire, host and transmit a given arbovirus. This intrinsic ability is known as “vector competence”. Based on whole transcriptome analysis, several genes and pathways have been predicated to have an association with a susceptible or refractory response in A. aegypti to DENV infection. However, the functional genomics of vector competence of A. aegypti is not well understood, primarily due to lack of integrative approaches in genomic or transcriptomic studies. In this review, we focus on the present status of genomics studies of DENV vector competence in A. aegypti as limited information is available relative to the other arboviruses. We propose future areas of research needed to facilitate the integration of vector and virus genomics and environmental factors to work towards better understanding of vector competence and vectorial capacity in natural conditions.

Peridomestic Aedes malayensis and Aedes albopictus are capable vectors of arboviruses in cities.

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Mendenhall, Ian H; Manuel, Menchie; Moorthy, Mahesh; Lee, Theodore T M; Low, Dolyce H W; Missé, Dorothée; Gubler, Duane J; Ellis, Brett R; Ooi, Eng Eong; Pompon, Julien

2017-06-01

Dengue and chikungunya are global re-emerging mosquito-borne diseases. In Singapore, sustained vector control coupled with household improvements reduced domestic mosquito populations for the past 45 years, particularly the primary vector Aedes aegypti. However, while disease incidence was low for the first 30 years following vector control implementation, outbreaks have re-emerged in the past 15 years. Epidemiological observations point to the importance of peridomestic infection in areas not targeted by control programs. We investigated the role of vectors in peri-domestic areas. We carried out entomological surveys to identify the Aedes species present in vegetated sites in highly populated areas and determine whether mosquitoes were present in open-air areas frequented by people. We compared vector competence of Aedes albopictus and Aedes malayensis with Ae. aegypti after oral infection with sympatric dengue serotype 2 and chikungunya viruses. Mosquito saliva was tested for the presence of infectious virus particles as a surrogate for transmission following oral infection. We identified Aedes albopictus and Aedes malayensis throughout Singapore and quantified their presence in forested and opened grassy areas. Both Ae. albopictus and Ae. malayensis can occupy sylvatic niches and were highly susceptible to both arboviruses. A majority of saliva of infected Ae. malayensis contained infectious particles for both viruses. Our study reveals the prevalence of competent vectors in peri-domestic areas, including Ae. malayensis for which we established the vector status. Epidemics can be driven by infection foci, which are epidemiologically enhanced in the context of low herd immunity, selective pressure on arbovirus transmission and the presence of infectious asymptomatic persons, all these conditions being present in Singapore. Learning from Singapore's vector control success that reduced domestic vector populations, but has not sustainably reduced arboviral incidence

Biological Control Strategies for Mosquito Vectors of Arboviruses.

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Huang, Yan-Jang S; Higgs, Stephen; Vanlandingham, Dana L

2017-02-10

Historically, biological control utilizes predatory species and pathogenic microorganisms to reduce the population of mosquitoes as disease vectors. This is particularly important for the control of mosquito-borne arboviruses, which normally do not have specific antiviral therapies available. Although development of resistance is likely, the advantages of biological control are that the resources used are typically biodegradable and ecologically friendly. Over the past decade, the advancement of molecular biology has enabled optimization by the manipulation of genetic materials associated with biological control agents. Two significant advancements are the discovery of cytoplasmic incompatibility induced by Wolbachia bacteria, which has enhanced replacement programs, and the introduction of dominant lethal genes into local mosquito populations through the release of genetically modified mosquitoes. As various arboviruses continue to be significant public health threats, biological control strategies have evolved to be more diverse and become critical tools to reduce the disease burden of arboviruses.

Development and field evaluation of the sentinel mosquito arbovirus capture kit (SMACK)

OpenAIRE

Johnson, Brian J.; Kerlin, Tim; Hall-Mendelin, Sonja; van den Hurk, Andrew F.; Cortis, Giles; Doggett, Stephen L.; Toi, Cheryl; Fall, Ken; McMahon, Jamie L.; Townsend, Michael; Ritchie, Scott A.

2015-01-01

Background Although sentinel animals are used successfully throughout the world to monitor arbovirus activity, ethical considerations and cross-reactions in serological assays highlight the importance of developing viable alternatives. Here we outline the development of a passive sentinel mosquito arbovirus capture kit (SMACK) that allows for the detection of arboviruses on honey-baited nucleic acid preservation cards (Flinders Technology Associates; FTA®) and has a similar trap efficacy as s...

Vertebrate reservoirs of arboviruses: myth, synonym of amplifier, or reality?

Czech Academy of Sciences Publication Activity Database

Kuno, G.; Mackenzie, J. S.; Junglen, S.; Hubálek, Zdeněk; Plyusnin, A.; Gubler, D. J.

2017-01-01

Roč. 9, č. 7 (2017), č. článku 185. ISSN 1999-4915 Institutional support: RVO:68081766 Keywords : insect-specific virus * arbovirus * transmission mechanism * vertebrate reservoir * origin of arbovirus * virus maintenance * zoonosis * host range Subject RIV: EE - Microbiology, Virology OBOR OECD: Virology Impact factor: 3.465, year: 2016

Biological Control Strategies for Mosquito Vectors of Arboviruses

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Yan-Jang S. Huang

2017-02-01

Full Text Available Historically, biological control utilizes predatory species and pathogenic microorganisms to reduce the population of mosquitoes as disease vectors. This is particularly important for the control of mosquito-borne arboviruses, which normally do not have specific antiviral therapies available. Although development of resistance is likely, the advantages of biological control are that the resources used are typically biodegradable and ecologically friendly. Over the past decade, the advancement of molecular biology has enabled optimization by the manipulation of genetic materials associated with biological control agents. Two significant advancements are the discovery of cytoplasmic incompatibility induced by Wolbachia bacteria, which has enhanced replacement programs, and the introduction of dominant lethal genes into local mosquito populations through the release of genetically modified mosquitoes. As various arboviruses continue to be significant public health threats, biological control strategies have evolved to be more diverse and become critical tools to reduce the disease burden of arboviruses.

Clinical and serological tests for arboviruses in free-living domestic pigeons (Columba livia).

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Ramos, Bruna Alves; Chiang, Jannifer Oliveira; Martins, Lívia Carício; Chagas, Liliane Leal das; Silva, Franko de Arruda E; Ferreira, Milene Silveira; Freitas, Maria Nazaré Oliveira; Alcantara, Bianca Nascimento de; Silva, Sandro Patroca da; Miranda, Stefânia Araújo; Sepulvreda, Barbara Alves; Corrêa, Layna Thayssa Guimarães; Negrão, Andréa Maria Góes; Vasconcelos, Pedro Fernando da Costa; Casseb, Alexandre do Rosário

2017-08-01

In this study, we evaluated the role of free-living domestic pigeons (Columba livia) as a reservoir of arboviruses in the city of Belém, state of Pará, Brazil. We investigated the presence of antibodies against the most prevalent arboviruses. This study was aimed at evaluating some clinical and physical parameters of domestic pigeons, including the presence of antibodies to Amazon-endemic arboviruses. Eighty-five healthy pigeons were captured in Mangal das Garças Park, in Belém, and were bled. Upon capture, the birds were subjected to a clinical examination in search of alterations that could indicate the presence of arboviruses. Blood samples were converted to serum and tested using the haemagglutination inhibition (HI) technique with a panel of 19 antigens of arboviruses circulating in the Amazon. The confirmation assay for the positive reactions to the viral species tested by HI was a neutralisation test in new-born Swiss albino mice (Mus musculus) [mouse neutralisation test (MNT)]. A total of 10 (11.8%) serum samples tested positive for antiflavivirus antibodies by HI. All the samples positive for the HI test were subjected to MNT for detection of viruses and yielded negative results (logarithmic neutralisation index < 1.7). The results represent the first serological detection of antiarbovirus antibodies in domestic pigeons as potential hosts of arboviruses in Brazil. The detection of haemagglutination-inhibiting antibodies against genus Flavivirus indicated that there was recent contact between the analysed domestic pigeons and these arboviruses. Further studies are needed to evaluate the role of free-living pigeons in the maintenance cycle and spread of arboviruses in the Amazon.

US and Cuban Scientists Forge Collaboration on Arbovirus Research.

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Pérez-Ávila, Jorge; Guzmán-Tirado, Maria G; Fraga-Nodarse, Jorge; Handley, Gray; Meegan, James; Pelegrino-Martínez de la Cotera, Jose L; Fauci, Anthony S

2018-04-01

After December 17, 2014, when the US and Cuban governments announced their intent to restore relations, the two countries participated in various exchange activities in an effort to encourage cooperation in public health, health research and biomedical sciences. The conference entitled Exploring Opportunities for Arbovirus Research Collaboration, hosted at Havana's Hotel Nacional, was part of these efforts and was the first major US-Cuban scientific conference in over 50 years. Its purpose was to share information about current arbovirus research and recent findings, and to explore opportunities for future joint research. The nearly 100 participants included leading arbovirus and vector transmission experts from ten US academic institutions, NIH, CDC, FDA and the US Department of Defense. Cuban participants included researchers, clinicians and students from Cuba's Ministry of Public Health, Pedro Kourí Tropical Medicine Institute, Center for Genetic Engineering and Biotechnology, Center for State Control of Medicines and Medical Devices and other health research and regulatory organizations. Topics highlighted at the three-day meeting included surveillance, research and epidemiology; pathogenesis, immunology and virology; treatment and diagnosis; vector biology and control; vaccine development and clinical trials; and regulatory matters. Concurrent breakout discussions focused on novel vector control, nonvector transmission, community engagement, Zika in pregnancy, and workforce development. Following the conference, the Pedro Kourí Tropical Medicine Institute and the US National Institute of Allergic and Infectious Diseases have continued to explore ways to encourage and support scientists in Cuba and the USA who wish to pursue arbovirus research cooperation to advance scientific discovery to improve disease prevention and control. KEYWORDS Arboviruses, flavivirus, Zika virus, chikungunya virus, dengue virus, research, disease vectors, Cuba, USA.

Factors responsible for the emergence of arboviruses; strategies, challenges and limitations for their control.

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Liang, Guodong; Gao, Xiaoyan; Gould, Ernest A

2015-03-01

Slave trading of Africans to the Americas, during the 16th to the 19th century was responsible for the first recorded emergence in the New World of two arthropod-borne viruses (arboviruses), yellow fever virus and dengue virus. Many other arboviruses have since emerged from their sylvatic reservoirs and dispersed globally due to evolving factors that include anthropological behaviour, commercial transportation and land-remediation. Here, we outline some characteristics of these highly divergent arboviruses, including the variety of life cycles they have developed and the mechanisms by which they have adapted to evolving changes in habitat and host availability. We cite recent examples of virus emergence that exemplify how arboviruses have exploited the consequences of the modern human lifestyle. Using our current understanding of these viruses, we also attempt to demonstrate some of the limitations encountered in developing control strategies to reduce the impact of future emerging arbovirus diseases. Finally, we present recommendations for development by an international panel of experts reporting directly to World Health Organization, with the intention of providing internationally acceptable guidelines for improving emerging arbovirus disease control strategies. Success in these aims should alleviate the suffering and costs encountered during recent decades when arboviruses have emerged from their sylvatic environment.

Development and field evaluation of the sentinel mosquito arbovirus capture kit (SMACK).

Science.gov (United States)

Johnson, Brian J; Kerlin, Tim; Hall-Mendelin, Sonja; van den Hurk, Andrew F; Cortis, Giles; Doggett, Stephen L; Toi, Cheryl; Fall, Ken; McMahon, Jamie L; Townsend, Michael; Ritchie, Scott A

2015-10-06

Although sentinel animals are used successfully throughout the world to monitor arbovirus activity, ethical considerations and cross-reactions in serological assays highlight the importance of developing viable alternatives. Here we outline the development of a passive sentinel mosquito arbovirus capture kit (SMACK) that allows for the detection of arboviruses on honey-baited nucleic acid preservation cards (Flinders Technology Associates; FTA®) and has a similar trap efficacy as standard light traps in our trials. The trap efficacy of the SMACK was assessed against Centers for Disease Control and Prevention (CDC) miniature light traps (standard and ultraviolet) and the Encephalitis Vector Survey (EVS) trap in a series of Latin square field trials conducted in North Queensland, Australia. The ability of the SMACK to serve as a sentinel arbovirus surveillance tool was assessed in comparison to Passive Box Traps (PBT) during the 2014 wet season in the Cairns, Australia region and individually in the remote Northern Peninsula Area (NPA) of Australia during the 2015 wet season. The SMACK caught comparable numbers of mosquitoes to both CDC light traps (mean capture ratio 0.86: 1) and consistently outperformed the EVS trap (mean capture ratio 2.28: 1) when CO2 was supplied by either a gas cylinder (500 ml/min) or dry ice (1 kg). During the 2014 arbovirus survey, the SMACK captured significantly (t 6 = 2.1, P = 0.04) more mosquitoes than the PBT, and 2 and 1 FTA® cards were positive for Ross River virus and Barmah Forest virus, respectively, while no arboviruses were detected from PBTs. Arbovirus activity was detected at all three surveillance sites during the NPA survey in 2015 and ca. 27 % of FTA® cards tested positive for either Murray Valley encephalitis virus (2 detections), West Nile virus (Kunjin subtype; 13 detections), or both viruses on two occasions. These results demonstrate that the SMACK is a versatile, simple, and effective passive arbovirus

Identification of Blood Meals from Potential Arbovirus Mosquito Vectors in the Peruvian Amazon Basin

OpenAIRE

Palermo, Pedro M.; Aguilar, Patricia V.; Sanchez, Juan F.; Zorrilla, Víctor; Flores-Mendoza, Carmen; Huayanay, Anibal; Guevara, Carolina; Lescano, Andrés G.; Halsey, Eric S.

2016-01-01

The transmission dynamics of many arboviruses in the Amazon Basin region have not been fully elucidated, including the vectors and natural reservoir hosts. Identification of blood meal sources in field-caught mosquitoes could yield information for identifying potential arbovirus vertebrate hosts. We identified blood meal sources in 131 mosquitoes collected from areas endemic for arboviruses in the Peruvian Department of Loreto by sequencing polymerase chain reaction amplicons of the cytochrom...

Mosquito fauna and arbovirus surveillance in a coastal Mississippi community after Hurricane Katrina.

Science.gov (United States)

Foppa, Ivo M; Evans, Christopher L; Wozniak, Arthur; Wills, William

2007-06-01

Hurricane Katrina caused massive destruction and flooding along the Gulf Coast in August 2005. We collected mosquitoes and tested them for arboviral infection in a severely hurricane-damaged community to determine species composition and to assess the risk of a mosquito-borne epidemic disease in that community about 6 wk after the landfall of Hurricane Katrina. Light-trap collections yielded 8,215 mosquitoes representing 19 species, while limited gravid-trap collections were not productive. The most abundant mosquito species was Culex nigripalpus, which constituted 73.6% of all specimens. No arboviruses were detected in any of the mosquitoes collected in this survey, which did not support the assertion that human risk for arboviral infection was increased in the coastal community 6 wk after the hurricane.

Viruses infecting reptiles.

Science.gov (United States)

Marschang, Rachel E

2011-11-01

A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch's postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

Viruses Infecting Reptiles

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Rachel E. Marschang

2011-11-01

Full Text Available A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

Longitudinal Analysis of Natural Killer Cells in Dengue Virus-Infected Patients in Comparison to Chikungunya and Chikungunya/Dengue Virus-Infected Patients.

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Caroline Petitdemange

2016-03-01

Full Text Available Dengue virus (DENV is the most prominent arbovirus worldwide, causing major epidemics in South-East Asia, South America and Africa. In 2010, a major DENV-2 outbreak occurred in Gabon with cases of patients co-infected with chikungunya virus (CHIKV. Although the innate immune response is thought to be of primordial importance in the development and outcome of arbovirus-associated pathologies, our knowledge of the role of natural killer (NK cells during DENV-2 infection is in its infancy.We performed the first extensive comparative longitudinal characterization of NK cells in patients infected by DENV-2, CHIKV or both viruses. Hierarchical clustering and principal component analyses were performed to discriminate between CHIKV and DENV-2 infected patients.We observed that both activation and differentiation of NK cells are induced during the acute phase of infection by DENV-2 and CHIKV. Combinatorial analysis however, revealed that both arboviruses induced two different signatures of NK-cell responses, with CHIKV more associated with terminal differentiation, and DENV-2 with inhibitory KIRs. We show also that intracellular production of interferon-γ (IFN-γ by NK cells is strongly stimulated in acute DENV-2 infection, compared to CHIKV.Although specific differences were observed between CHIKV and DENV-2 infections, the significant remodeling of NK cell populations observed here suggests their potential roles in the control of both infections.

Preliminary investigation of Culicidae species in South Pantanal, Brazil and their potential importance in arbovirus transmission.

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Pauvolid-Corrêa, Alex; Tavares, Fernando Neto; Alencar, Jeronimo; Silva, Julia dos Santos; Murta, Michele; Serra-Freire, Nicolau Maués; Pellegrin, Aiesca Oliveira; Gil-Santana, Hélcio; Guimarães, Anthony Erico; Silva, Edson Elias da

2010-01-01

In view of the high circulation of migratory birds and the environmental and climatic conditions which favor the proliferation of arthropods, the Brazilian Pantanal is susceptible to circulation of arboviruses. However, the amount of data concerning arbovirus vectors in this area is scarce; therefore the aim of this study was to conduct a preliminary investigation of Culicidae species in the Nhecolândia Sub-region of South Pantanal, Brazil and their potential importance in the arbovirus transmission. A total of 3684 specimens of mosquitoes were captured, 1689 of which caught in the rainy season of 2007, were divided into 78 pools and submitted to viral isolation, Semi-Nested RT-PCR and Nested RT-PCR, with a view to identifying the most important arboviruses in Brazil. Simultaneously, 70 specimens of ticks found blood-feeding on horses were also submitted to the same virological assays. No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, a total of 22 Culicidae species were identified, ten of which had previously been reported as vectors of important arboviruses. The diversity of species found blood-feeding on human and horse hosts together with the arboviruses circulation previously reported suggest that the Nhecolândia Sub-region of South Pantanal is an important area for arbovirus surveillance in Brazil.

Addressing knowledge gaps in molecular, sero-surveillance and monitoring approaches on Zika epidemics and other arbovirus co-infections: A structured review

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Ernest Tambo

2017-05-01

Full Text Available Globalization, with consequent increased travel and trade, rapid urbanization and growing weather variation events due to climate change has contributed to the recent unprecedented Zika virus (ZIKV pandemic. This has emphasized the pressing need for local, national, regional and global community collaborative proactiveness, leadership and financial investment resilience in research and development. This paper addresses the potential knowledge gaps and impact of early detection and monitoring approaches on ZIKV epidemics and related arboviral infections steered towards effective prevention and smart response strategies. We advocate for the development and validation of robust field and point of care diagnostic tools that are more sensitive, specific and cost effective for use in ZIKV epidemics and routine pathophysiology surveillance and monitoring systems as an imperative avenue in understanding Zika-related and other arbovirus trends and apply genomic and proteomic characterisation approaches in guiding annotation efforts in order to design and implement public health burden mitigation and adaptation strategies.

Hepatic disorder in Zika virus infection

Institute of Scientific and Technical Information of China (English)

Viroj Wiwanitkit

2016-01-01

Zika virus infection is the present global problem. This arbovirus infection can cause acute ilness and affect fetus in utero. However, there can be other additional clinical manifestation including to the hepatic disorder. In this short commentary article, the author brielfy discusses on the liver problem due to Zika virus infection.

Identification of Blood Meals from Potential Arbovirus Mosquito Vectors in the Peruvian Amazon Basin.

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Palermo, Pedro M; Aguilar, Patricia V; Sanchez, Juan F; Zorrilla, Víctor; Flores-Mendoza, Carmen; Huayanay, Anibal; Guevara, Carolina; Lescano, Andrés G; Halsey, Eric S

2016-11-02

The transmission dynamics of many arboviruses in the Amazon Basin region have not been fully elucidated, including the vectors and natural reservoir hosts. Identification of blood meal sources in field-caught mosquitoes could yield information for identifying potential arbovirus vertebrate hosts. We identified blood meal sources in 131 mosquitoes collected from areas endemic for arboviruses in the Peruvian Department of Loreto by sequencing polymerase chain reaction amplicons of the cytochrome b gene. Psorophora (Janthinosoma) albigenu, Psorophora (Grabhamia) cingulata, Mansonia humeralis, Anopheles oswaldoi s.l., and Anopheles benarrochi s.l. had mainly anthropophilic feeding preferences; Aedes (Ochlerotatus) serratus, and Aedes (Ochlerotatus) fulvus had feeding preferences for peridomestic animals; and Culex (Melanoconion) spp. fed on a variety of vertebrates, mainly rodents (spiny rats), birds, and amphibians. On the basis of these feeding preferences, many mosquitoes could be considered as potential enzootic and bridge arbovirus vectors in the Amazon Basin of Peru. © The American Society of Tropical Medicine and Hygiene.

Arboviruses in North Dakota, 2003–2006

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Anderson, John F.; Main, Andy J.; Armstrong, Philip M.; Andreadis, Theodore G.; Ferrandino, Francis J.

2015-01-01

To investigate arbovirus transmission in North Dakota, we collected and screened mosquitoes for viral infection by Vero cell culture assay. Seven viruses were isolated from 13 mosquito species. Spatial and temporal distributions of the important vectors of West Nile virus (WNV), Cache Valley virus, Jamestown Canyon virus (JCV), and trivittatus virus are reported. Snowshoe hare virus, Potosi virus, and western equine encephalomyelitis virus were also isolated. The risks of Culex tarsalis and Aedes vexans transmitting WNV to humans were 61.4% and 34.0% in 2003–2006, respectively, but in 2003 when the largest epidemic was reported, risks for Ae. vexans and Cx. tarsalis in Cass County were 73.6% and 23.9%, respectively. Risk of humans acquiring an infectious bite was greatest from about the second week of July through most of August. West Nile virus sequences were of the WN02 genotype. Most JCV strains belonged to a single clade of genetically related strains. Cache Valley virus and JCV were prevalent during August and early September and during July and August, respectively. PMID:25487728

Zoonotic encephalitides caused by arboviruses: transmission and epidemiology of alphaviruses and flaviviruses.

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Go, Yun Young; Balasuriya, Udeni B R; Lee, Chong-Kyo

2014-01-01

In this review, we mainly focus on zoonotic encephalitides caused by arthropod-borne viruses (arboviruses) of the families Flaviviridae (genus Flavivirus) and Togaviridae (genus Alphavirus) that are important in both humans and domestic animals. Specifically, we will focus on alphaviruses (Eastern equine encephalitis virus, Western equine encephalitis virus, Venezuelan equine encephalitis virus) and flaviviruses (Japanese encephalitis virus and West Nile virus). Most of these viruses were originally found in tropical regions such as Africa and South America or in some regions in Asia. However, they have dispersed widely and currently cause diseases around the world. Global warming, increasing urbanization and population size in tropical regions, faster transportation and rapid spread of arthropod vectors contribute in continuous spreading of arboviruses into new geographic areas causing reemerging or resurging diseases. Most of the reemerging arboviruses also have emerged as zoonotic disease agents and created major public health issues and disease epidemics.

Mosquito-borne arbovirus surveillance at selected sites in diverse ecological zones of Kenya; 2007 – 2012

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2013-01-01

Background Increased frequency of arbovirus outbreaks in East Africa necessitated the determination of distribution of risk by entomologic arbovirus surveillance. A systematic vector surveillance programme spanning 5 years and covering 11 sites representing seven of the eight provinces in Kenya and located in diverse ecological zones was carried out. Methods Mosquitoes were sampled bi-annually during the wet seasons and screened for arboviruses. Mosquitoes were identified to species, pooled by species, collection date and site and screened for arboviruses by isolation in cell culture and/or RT-PCR screening and sequencing. Results Over 450,000 mosquitoes in 15,890 pools were screened with 83 viruses being detected/isolated that include members of the alphavirus, flavivirus and orthobunyavirus genera many of which are known to be of significant public health importance in the East African region. These include West Nile, Ndumu, Sindbis, Bunyamwera, Pongola and Usutu viruses detected from diverse sites. Ngari virus, which was associated with hemorrhagic fever in northern Kenya in 1997/98 was isolated from a pool of Anopheles funestus sampled from Tana-delta and from Aedes mcintoshi from Garissa. Insect only flaviviruses previously undescribed in Kenya were also isolated in the coastal site of Rabai. A flavivirus most closely related to the Chaoyang virus, a new virus recently identified in China and two isolates closely related to Quang Binh virus previously unreported in Kenya were also detected. Conclusion Active transmission of arboviruses of public health significance continues in various parts of the country with possible undetermined human impact. Arbovirus activity was highest in the pastoralist dominated semi-arid to arid zones sites of the country where 49% of the viruses were isolated suggesting a role of animals as amplifiers and indicating the need for improved arbovirus disease diagnosis among pastoral communities. PMID:23663381

The costs of infection and resistance as determinants of West Nile virus susceptibility in Culex mosquitoes

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Styer Linda M

2011-10-01

Full Text Available Abstract Background Understanding the phenotypic consequences of interactions between arthropod-borne viruses (arboviruses and their mosquito hosts has direct implications for predicting the evolution of these relationships and the potential for changes in epidemiological patterns. Although arboviruses are generally not highly pathogenic to mosquitoes, pathology has at times been noted. Here, in order to evaluate the potential costs of West Nile virus (WNV infection and resistance in a primary WNV vector, and to assess the extent to which virus-vector relationships are species-specific, we performed fitness studies with and without WNV exposure using a highly susceptible Culex pipiens mosquito colony. Specifically, we measured and compared survival, fecundity, and feeding rates in bloodfed mosquitoes that were (i infected following WNV exposure (susceptible, (ii uninfected following WNV exposure (resistant, or (iii unexposed. Results In contrast to our previous findings with a relatively resistant Cx. tarsalis colony, WNV infection did not alter fecundity or blood-feeding behaviour of Cx. pipiens, yet results do indicate that resistance to infection is associated with a fitness cost in terms of mosquito survival. Conclusions The identification of species-specific differences provides an evolutionary explanation for variability in vector susceptibility to arboviruses and suggests that understanding the costs of infection and resistance are important factors in determining the potential competence of vector populations for arboviruses.

Acute viral infections of the central nervous system, 2014-2016, Greece.

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Papa, Anna; Papadopoulou, Elpida

2018-04-01

In order to investigate the viral etiology of acute infections of central nervous system (CNS), multiplex and single PCRs combined with serology for arboviruses were applied on samples from 132 hospitalized patients in Greece during May 2014-December 2016. A viral pathogen was detected in 52 of 132 (39.4%) cases with acute CNS infection. Enteroviruses predominated (15/52, 28.8%), followed by West Nile virus (9/52, 17.3%). Phleboviruses, varicella-zoster virus, and Epstein-Barr virus accounted for 15.4%, 13.5%, and 11.5% of the cases, respectively. The study gives an insight into the etiology of viral CNS infections in a Mediterranean country, where arboviruses should be included in the differential diagnosis of acute CNS infections. © 2017 Wiley Periodicals, Inc.

(Arbo)viruses in high European Arctic

OpenAIRE

ELSTEROVÁ, Jana

2016-01-01

Since an ongoing climate change covers strongly the polar areas. Higher temperatures and related climate parameters bring the emergence of new parasites and their pathogens to higher latitudes. This may influence zoonotic diseases including arthropod-transmitted diseases. The tick species Ixodes uriae, parasitizing seabirds in the Arctic, may transmit many pathogens including various arboviruses, Borrelia spirochetes and Babesia apicomplexans. In the study we diagnosed 89 individuals of seabi...

Enveloped virus-like particles as vaccines against pathogenic arboviruses

NARCIS (Netherlands)

Pijlman, G.P.

2015-01-01

Arthropod-borne arboviruses form a continuous threat to human and animal health, but few arboviral vaccines are currently available. Advances in expression technology for complex, enveloped virus-like particles (eVLPs) create new opportunities to develop potent vaccines against pathogenic

[Entomologic situation regarding arbovirus circulation in the Guajaibon area].

Science.gov (United States)

Fuentes González, O; Fernández Martínez, A; Castex Rodríguez, M; Pelegrino Martínez, J L

1989-01-01

The collections of culicidae made in the Guajaibón area, North coast of Havana province, are analyzed with arbovirologic purposes. The predominance of Aedes scapularis in the human bait collections is confirmed. The possibility of arbovirus circulation in the area is suggested.

Collection & Processing of Medically Important Arthropods for Arbovirus Isolation.

Science.gov (United States)

Sudia, W. Daniel; Chamberlain, Roy W.

The methods given for collecting, preserving, and processing mosquitoes and other archropods for isolation of arboviruses are those used by the National Communicable Disease Center. Techniques of collecting mosquitoes as they bite, using light or bait traps, and from their daytime resting sites are described and illustrated. Details of subsequent…

Strengthening Preparedness for Arbovirus Infections in Mediterranean and Black Sea Countries: A Conceptual Framework to Assess Integrated Surveillance in the Context of the One Health Strategy

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Maria Grazia Dente

2018-03-01

Full Text Available In the context of One Health, there is presently an effort to integrate surveillance of human, animal, entomological, and environmental sectors. This aims to strengthen the prevention of, and preparedness against, arbovirus infections, also in the light of environmental and climate changes that could increase the risk of transmission. However, criteria to define integrated surveillance, and to compare different systems, still need to be identified and tested. We conducted a scoping review to identify and examine surveillance systems for West Nile virus (WNV, chikungunya virus (CHKV, dengue virus (DENV, and Rift Valley fever virus (RVFV, which involve human, animal, entomological, and environmental sectors. We analyzed findings using a conceptual framework we developed for this purpose. The review highlights that the criteria proposed in the conceptual framework to describe integrated surveillance are consistently reported in the context of studies and programs related to integrated surveillance of the selected arboviral diseases. These criteria can facilitate the identification and description of operationalized One Health surveillance.

Strengthening Preparedness for Arbovirus Infections in Mediterranean and Black Sea Countries: A Conceptual Framework to Assess Integrated Surveillance in the Context of the One Health Strategy.

Science.gov (United States)

Dente, Maria Grazia; Riccardo, Flavia; Nacca, Gloria; Ranghiasci, Alessia; Escadafal, Camille; Gaayeb, Lobna; Jiménez-Clavero, Miguel Angel; Manuguerra, Jean-Claude; Picard, Marie; Fernández-Pinero, Jovita; Pérez-Ramírez, Elisa; Robert, Vincent; Victoir, Kathleen; Declich, Silvia

2018-03-10

In the context of One Health, there is presently an effort to integrate surveillance of human, animal, entomological, and environmental sectors. This aims to strengthen the prevention of, and preparedness against, arbovirus infections, also in the light of environmental and climate changes that could increase the risk of transmission. However, criteria to define integrated surveillance, and to compare different systems, still need to be identified and tested. We conducted a scoping review to identify and examine surveillance systems for West Nile virus (WNV), chikungunya virus (CHKV), dengue virus (DENV), and Rift Valley fever virus (RVFV), which involve human, animal, entomological, and environmental sectors. We analyzed findings using a conceptual framework we developed for this purpose. The review highlights that the criteria proposed in the conceptual framework to describe integrated surveillance are consistently reported in the context of studies and programs related to integrated surveillance of the selected arboviral diseases. These criteria can facilitate the identification and description of operationalized One Health surveillance.

Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection.

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Michael J Conway

2016-09-01

Full Text Available Aedes aegypti is the primary vector of several medically relevant arboviruses including dengue virus (DENV types 1-4. Ae. aegypti transmits DENV by inoculating virus-infected saliva into host skin during probing and feeding. Ae. aegypti saliva contains over one hundred unique proteins and these proteins have diverse functions, including facilitating blood feeding. Previously, we showed that Ae. aegypti salivary gland extracts (SGEs enhanced dissemination of DENV to draining lymph nodes. In contrast, HPLC-fractionation revealed that some SGE components inhibited infection. Here, we show that D7 proteins are enriched in HPLC fractions that are inhibitory to DENV infection, and that recombinant D7 protein can inhibit DENV infection in vitro and in vivo. Further, binding assays indicate that D7 protein can directly interact with DENV virions and recombinant DENV envelope protein. These data reveal a novel role for D7 proteins, which inhibits arbovirus transmission to vertebrates through a direct interaction with virions.

Co-infections with Chikungunya and Dengue Viruses, Guatemala, 2015.

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Edwards, Thomas; Signor, Leticia Del Carmen Castillo; Williams, Christopher; Donis, Evelin; Cuevas, Luis E; Adams, Emily R

2016-11-01

We screened serum samples referred to the national reference laboratory in Guatemala that were positive for chikungunya or dengue viruses in June 2015. Co-infection with both viruses was detected by reverse transcription PCR in 46 (32%) of 144 samples. Specimens should be tested for both arboviruses to detect co-infections.

Arbovirus vaccines: opportunities for the baculovirus-insect cell expression system

NARCIS (Netherlands)

Metz, S.W.H.; Pijlman, G.P.

2011-01-01

The baculovirus-insect cell expression system is a well-established technology for the production of heterologous viral (glyco)proteins in cultured cells, applicable for basic scientific research as well as for the development and production of vaccines and diagnostics. Arboviruses form an emerging

Dengue and Zika viruses: lessons learned from the similarities between these Aedes mosquito-vectored arboviruses.

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Suwanmanee, San; Luplertlop, Natthanej

2017-02-01

The currently spreading arbovirus epidemic is having a severe impact on human health worldwide. The two most common flaviviruses, dengue virus (DENV) and Zika virus (ZIKV), are transmitted through the same viral vector, Aedes spp. mosquitoes. Since the discovery of DENV in 1943, this virus has been reported to cause around 390 million human infections per year, approximately 500,000 of which require hospitalization and over 20,000 of which are lethal. The present DENV epidemic is primarily concentrated in Southeast Asia. ZIKV, which was discovered in 1952, is another important arthropod-borne flavivirus. The neurotropic role of ZIKV has been reported in infected newborns with microcephaly and in adults with Guillain-Barre syndrome. Despite DENV and ZIKV sharing the same viral vector, their complex pathogenic natures are poorly understood, and the infections they cause do not have specific treatments or effective vaccines. Therefore, this review will describe what is currently known about the clinical characteristics, pathogenesis mechanisms, and transmission of these two viruses. Better understanding of the interrelationships between DENV and ZIKV will provide a useful perspective for developing an effective strategy for controlling both viruses in the future.

Differential outcomes of Zika virus infection in Aedes aegypti orally challenged with infectious blood meals and infectious protein meals.

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Huang, Yan-Jang S; Lyons, Amy C; Hsu, Wei-Wen; Park, So Lee; Higgs, Stephen; Vanlandingham, Dana L

2017-01-01

Infection of mosquitoes is an essential step for the transmission of mosquito-borne arboviruses in nature. Engorgement of infectious blood meals from viremic infected vertebrate hosts allows the entry of viruses and initiates infection of midgut epithelial cells. Historically, the infection process of arboviruses in mosquitoes has been studied through the engorgement of mosquitoes from viremic laboratory animals or from artificial feeders containing blood mixed with viruses harvested from cell cultures. The latter approach using so-called artificial blood meals is more frequently used since it is readily optimized to maximize viral titer, negates the use of animals and can be used with viruses for which there are no small animal models. Use of artificial blood meals has enabled numerous studies on mosquito infections with a wide variety of viruses; however, as described here, with suitable modification it can also be used to study the interplay between infection, specific blood components, and physiological consequences associated with blood engorgement. For hematophagous female mosquitoes, blood is the primary nutritional source supporting all physiological process including egg development, and also influences neurological processes and behaviors such as host-seeking. Interactions between these blood-driven vector biological processes and arbovirus infection that is mediated via blood engorgement have not yet been specifically studied. This is in part because presentation of virus in whole blood inevitably induces enzymatic digestion processes, hormone driven oogenesis, and other biological changes. In this study, the infection process of Zika virus (ZIKV) in Aedes aegypti was characterized by oral exposure via viral suspension meals within minimally bovine serum albumin complemented medium or within whole blood. The use of bovine serum albumin in infectious meals provides an opportunity to evaluate the role of serum albumin during the process of flavivirus

Poverty and Arbovirus Outbreaks: When Chikungunya Virus Hits More Precarious Populations Than Dengue Virus in French Guiana.

Science.gov (United States)

Bonifay, Timothée; Douine, Maylis; Bonnefoy, Clémence; Hurpeau, Benoit; Nacher, Mathieu; Djossou, Félix; Epelboin, Loïc

2017-01-01

Since 2013, 3 successive arbovirus outbreaks, dengue (DENV), chikungunya (CHIKV), and Zika virus, have occurred in French Guiana (FG). The primary objective of this study was to describe the socioeconomic indicators of the first patients infected with CHIKV during the outbreak of 2014. The secondary objective was to compare those patients with patient infected by DENV and with the local population. A monocentric, retrospective, case-control study was conducted in Cayenne hospital in FG comparing a group of patients infected with CHIKV in 2014 with a group infected with DENV in 2013. Children aged less than 15 years and pregnant women were excluded. A total of 168 CHIKV patients were compared with 168 DENV patients. Factors associated with CHIKV were living in poor neighborhoods (82% vs 44%; odds ratio [OR], 5.81; 95% confidence interval [CI], 3.35-10.2), having a precarious status (54% vs 33%; OR, 2.37; 95% CI, 1.49-3.78), and being born abroad (70% vs 35%; OR, 4.35; 95% CI, 2.69-7.06). The present results suggest that early in the epidemic, the populations most at risk for CHIKV infection were the most socially vulnerable populations in the poorest neighborhoods, whereas DENV appeared to have affected a richer population and richer areas.

Arbovirus circulation, temporal distribution, and abundance of mosquito species in two Carolina bay habitats.

Science.gov (United States)

Ortiz, D I; Wozniak, A; Tolson, M W; Turner, P E

2005-01-01

Carolina bays, a type of geomorphic feature, may be important in the ecology of mosquito vectors in South Carolina. Their hydrology varies from wetland habitats with marked flooding/drying regimes to permanently flooded spring-fed lakes. Moreover, they possess characteristics that contribute to the support of a particularly abundant and diverse invertebrate fauna. Although it has been estimated that 2,700+ bays exist in South Carolina, approximately 97% have been altered; Heritage Preserve (SBHP) and Woods Bay State Park (WBSP), from June 1997 to July 1998 to determine mosquito temporal distribution, species composition, and the occurrence of arbovirus activity. The largest mosquito collection was obtained at WBSP (n = 31,172) representing 25 species followed by SBHP (n = 3,940) with 24 species. Anopheles crucians complex were the most common species encountered in both bays. Two virus isolates were obtained from SBHP in 1997: Keystone (KEY) virus from Ochlerotatus atlanticus-tormentor and Cache Valley (CV) virus from Oc. canadensis canadensis. Twenty-nine (29) arbovirus-positive pools were obtained from WBSP: 28 in 1997 and one in 1998. KEY virus was isolated from three pools of Oc. atlanticus-tormentor and Tensaw (TEN) virus was isolated from two pools of An. crucians complex; 10 isolates could not be identified with the sera available. Additionally, 14 pools of An. crucians complex tested positive for Eastern equine encephalitis (EEE) virus antigen. These represent the first record of KEY and CV viruses in South Carolina. Our data indicate the presence of high mosquito density and diversity in both Carolina bay habitats, which may be influenced, in part, by seasonal changes in their hydroperiods. The study of mosquito and arbovirus ecology in Carolina Bay habitats could provide more information on the transmission dynamics of arboviruses and its impact on human and animal arboviral disease occurrence in South Carolina.

[Arboviruses also have an American dream].

Science.gov (United States)

Rodhain, F

2017-08-01

Some arboviruses that originated in the Old World have been introduced by humans into the American continent. The first of them was the yellow fever virus, coming from the West African coast with slaves in the 17th-19th centuries, followed by dengue viruses, which were always prevalent within the Americas. Next was theWest Nile virus, introduced in New York in 1999, that spread in only a few years over the whole continent. Then, Chikungunya virus arrived on Saint Martin Island in 2013 after its outbreak in Polynesia; it is now widespread in the Caribbean Islands and on the American continent from the United States to Brazil. Finally, Zika virus, already active in Asia and in the South Pacific region, was introduced in Brazil and spread between the southern part of United States and south Brazil. These unexpected emergences are the consequence of the generalization of transoceanic trading; so, it is humans who are truly responsible for such transportation of viruses from the African and Asian continents. The mechanisms of virus establishment in unusual ecosystems have to be analyzed in order to understand the conditions for the circulation of the viruses, which supposes an adaptation to new hosts and vectors that are sometimes local species (like Culex vectors of West Nile virus) but mainly previously introduced mosquitoes (like Aedes aegypti and/or Aedes albopictus). Over time, all these vectors developed a strong anthropophily and, most of them, a remarkable adaptation to urban environment; hence, these arboviruses can disseminate both in rural and urban context. This type of arboviral emergences will certainly continue in the following years and we must imperatively develop preventive strategies by detecting virus mutations with capacity for emergence, enhancing the sensibility and rapidity of epidemiological surveillance, and becoming ready to face such events that cause a truly international health crisis.

Evolution of Mosquito-Based Arbovirus Surveillance Systems in Australia

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Andrew F. van den Hurk

2012-01-01

Full Text Available Control of arboviral disease is dependent on the sensitive and timely detection of elevated virus activity or the identification of emergent or exotic viruses. The emergence of Japanese encephalitis virus (JEV in northern Australia revealed numerous problems with performing arbovirus surveillance in remote locations. A sentinel pig programme detected JEV activity, although there were a number of financial, logistical, diagnostic and ethical limitations. A system was developed which detected viral RNA in mosquitoes collected by solar or propane powered CO2-baited traps. However, this method was hampered by trap-component malfunction, microbial contamination and large mosquito numbers which overwhelmed diagnostic capabilities. A novel approach involves allowing mosquitoes within a box trap to probe a sugar-baited nucleic-acid preservation card that is processed for expectorated arboviruses. In a longitudinal field trial, both Ross River and Barmah Forest viruses were detected numerous times from multiple traps over different weeks. Further refinements, including the development of unpowered traps and use of yeast-generated CO2, could enhance the applicability of this system to remote locations. New diagnostic technology, such as next generation sequencing and biosensors, will increase the capacity for recognizing emergent or exotic viruses, while cloud computing platforms will facilitate rapid dissemination of data.

The immune strategies of mosquito Aedes aegypti against microbial infection.

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Wang, Yan-Hong; Chang, Meng-Meng; Wang, Xue-Li; Zheng, Ai-Hua; Zou, Zhen

2018-06-01

Yellow fever mosquito Aedes aegypti transmits many devastating arthropod-borne viruses (arboviruses), such as dengue virus, yellow fever virus, Chikungunya virus, and Zika virus, which cause great concern to human health. Mosquito control is an effective method to block the spread of infectious diseases. Ae. aegypti uses its innate immune system to fight against arboviruses, parasites, and fungi. In this review, we briefly summarize the recent findings in the immune response of Ae. aegypti against arboviral and entomopathogenic infections. This review enriches our understanding of the mosquito immune system and provides evidence to support the development of novel mosquito control strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mosquitoes used to draw blood for arbovirus viremia determinations in small vertebrates.

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Rebekah C Kading

Full Text Available Serial samples from the same individuals may be required for certain virological studies, however, some small animals cannot easily be blood-sampled. Therefore, we evaluated the use of Culex quinquefasciatus Say and Aedes albopictus Skuse mosquitoes as "biological syringes" to draw blood for virus titer determinations in small vertebrates. Groups of chicks (Gallus gallus, hamsters (Mesocricetus auratus, and house sparrows (Passer domesticus were experimentally infected with West Nile virus (WNV or Highlands J virus (HJV. In general, good correlation was seen between mosquito- and syringe-derived blood samples at titers ≥5.0 log10 pfu/mL serum as compared with titers 105 pfu/mL serum had mosquito- and syringe-derived titers within one log of each other. Sparrow viremia profiles generated from single mosquito blood meals and syringe were not significantly different (p>0.05. This technique is valuable for assessing the roles of small vertebrates in the ecologies of arboviruses, and could be used in applications beyond virology and infectious diseases, when <10 µL of whole blood is required.

Serological Evidence of Contrasted Exposure to Arboviral Infections between Islands of the Union of Comoros (Indian Ocean.

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Koussay Dellagi

2016-12-01

Full Text Available A cross sectional serological survey of arboviral infections in humans was conducted on the three islands of the Union of Comoros, Indian Ocean, in order to test a previously suggested contrasted exposure of the three neighboring islands to arthropod-borne epidemics. Four hundred human sera were collected on Ngazidja (Grande Comore, Mwali (Mohéli and Ndzouani (Anjouan, and were tested by ELISA for IgM and/or IgG antibodies to Dengue (DENV, Chikungunya (CHIKV, Rift Valley fever (RVFV, West Nile (WNV, Tick borne encephalitis (TBEV and Yellow fever (YFV viruses and for neutralizing antibodies to DENV serotypes 1-4. Very few sera were positive for IgM antibodies to the tested viruses indicating that the sero-survey was performed during an inter epidemic phase for the investigated arbovirus infections, except for RVF which showed evidence of recent infections on all three islands. IgG reactivity with at least one arbovirus was observed in almost 85% of tested sera, with seropositivity rates increasing with age, indicative of an intense and long lasting exposure of the Comorian population to arboviral risk. Interestingly, the positivity rates for IgG antibodies to DENV and CHIKV were significantly higher on Ngazidja, confirming the previously suggested prominent exposure of this island to these arboviruses, while serological traces of WNV infection were detected most frequently on Mwali suggesting some transmission specificities associated with this island only. The study provides the first evidence for circulation of RVFV in human populations from the Union of Comoros and further suggests that the virus is currently circulating on the three islands in an inconspicuous manner. This study supports contrasted exposure of the islands of the Comoros archipelago to arboviral infections. The observation is discussed in terms of ecological factors that may affect the abundance and distribution of vector populations on the three islands as well as concurring

Differential protein modulation in midguts of Aedes aegypti infected with chikungunya and dengue 2 viruses.

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Tchankouo-Nguetcheu, Stéphane; Khun, Huot; Pincet, Laurence; Roux, Pascal; Bahut, Muriel; Huerre, Michel; Guette, Catherine; Choumet, Valérie

2010-10-05

Arthropod borne virus infections cause several emerging and resurgent infectious diseases. Among the diseases caused by arboviruses, dengue and chikungunya are responsible for a high rate of severe human diseases worldwide. The midgut of mosquitoes is the first barrier for pathogen transmission and is a target organ where arboviruses must replicate prior to infecting other organs. A proteomic approach was undertaken to characterize the key virus/vector interactions and host protein modifications that happen in the midgut for viral transmission to eventually take place. Using a proteomics differential approach with two-Dimensional Differential in-Gel Electrophoresis (2D-DIGE), we defined the protein modulations in the midgut of Aedes aegypti that were triggered seven days after an oral infection (7 DPI) with dengue 2 (DENV-2) and chikungunya (CHIKV) viruses. Gel profile comparisons showed that the level of 18 proteins was modulated by DENV-2 only and 12 proteins were modulated by CHIKV only. Twenty proteins were regulated by both viruses in either similar or different ways. Both viruses caused an increase of proteins involved in the generation of reactive oxygen species, energy production, and carbohydrate and lipid metabolism. Midgut infection by DENV-2 and CHIKV triggered an antioxidant response. CHIKV infection produced an increase of proteins involved in detoxification. Our study constitutes the first analysis of the protein response of Aedes aegypti's midgut infected with viruses belonging to different families. It shows that the differentially regulated proteins in response to viral infection include structural, redox, regulatory proteins, and enzymes for several metabolic pathways. Some of these proteins like antioxidant are probably involved in cell protection. On the other hand, we propose that the modulation of other proteins like transferrin, hsp60 and alpha glucosidase, may favour virus survival, replication and transmission, suggesting a subversion of

[Arbovirus circulation in the Republic of Guinea].

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Butenko, A M

1996-01-01

In 1978-1991 the USSR-Guinea Virological and Microbiological Laboratory functioned in Kindia, the Republic of Guinea. Arbovirus activity in this country was studied by a number of virologists and other specialists. Their personal contribution and achievements in this collaboration are reflected in the present paper. About 74,000 mosquitoes, 100,000 Ixodidae ticks, 1,500 wild birds, 2,700 bats, 106 monkeys, and 308 other mammals, 927 blood samples collected from febrile patients were examined in 1978-1989, using inoculation of new-born white mice. As a result of this work 127 strains of the following arboviruses were isolated: Chikungunia (1 strain), Dengue 2 (4), Saboya (7), Wesselsbron (1), Bunyamwera (4), M'Poko (5), Rift Valley Fever (6), CHF-Congo (9), Dugbe (22), Bhanja (6), Forecariah (2), Jos (26), Abadina (15), Kindia (2), Ark 6956 (1), Fomede (2), Bluetongue (9), Mossuril (2), AnK 6009 (1), and Kolente (2). Dengue 2, Wesselsbron, Bunyamwera, M'Poko, Kindia, Mossuril viruses were isolated from mosquitoes. Ixodidae ticks were sources for isolation of Chikungunia, Saboya, CCHF, Dugbe, Bhanja, Forecaciah, Jos, Abadina, Kindia, Ark 6956, Fomede, Bluetongue, and Kolente viruses. Saboya, RVF, Fomede, Kolente, AnK 6909 were isolated from bats (Chiroptera); Saboya, Abadina, and Bluetongue viruses from birds. One strain of Dugbe virus was originated from the brain of Cercopithecus patas. Bunyamwera and Abadina viruses were isolated from the blood of two febrile patients. Serological identification of many strains was kindly conducted at the Pasteur Institute, Dakar (J. P.Digoutte) and some at the YARU, USA (R. Shope). Kindia and Ark 6956 (Reovirus, gr. Palyam), Fomede (gr. Chobar Gorge), Forecariah (Bunyavirus, gr. Bhanja), Kolente (Rhabdovirus) were identified as an original type of Lagos bat virus. The results of seroepidemiological surveys are also presented.

Seroprevalence of arboviruses among blood donors in French Polynesia, 2011–2013

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Maite Aubry

2015-12-01

Conclusions: These results corroborate the expected high transmission of DENV and conversely suggest that no active circulation of ZIKV, JEV, and WNV occurred in French Polynesia before 2011. Information provided by this study may be useful for public health authorities to improve surveillance and implement strategies to prevent the transmission of arboviruses.

The neglected arboviral infections in mainland China.

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Xiaoyan Gao

2010-04-01

Full Text Available The major arboviral diseases in mainland China include Japanese encephalitis, dengue fever, Crimean-Congo hemorrhagic fever (also known as Xinjiang hemorrhagic fever, and tick-borne encephalitis. These and other newly found arbovirus infections due to Banna virus and Tahyna virus contribute to a large and relatively neglected disease burden in China. Here we briefly review the literature regarding these arboviral infections in mainland China with emphasis on their epidemiology, primary vectors, phylogenetic associations, and the prevention programs associated with these agents in China.

Virus Infections on Prion Diseased Mice Exacerbate Inflammatory Microglial Response

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Lins, Nara; Mourão, Luiz; Trévia, Nonata; Passos, Aline; Farias, José Augusto; Assunção, Jarila; Bento-Torres, João; Consentino Kronka Sosthenes, Marcia; Diniz, José Antonio Picanço; Vasconcelos, Pedro Fernando da Costa

2016-01-01

We investigated possible interaction between an arbovirus infection and the ME7 induced mice prion disease. C57BL/6, females, 6-week-old, were submitted to a bilateral intrahippocampal injection of ME7 prion strain (ME7) or normal brain homogenate (NBH). After injections, animals were organized into two groups: NBH (n = 26) and ME7 (n = 29). At 15th week after injections (wpi), animals were challenged intranasally with a suspension of Piry arbovirus 0.001% or with NBH. Behavioral changes in ME7 animals appeared in burrowing activity at 14 wpi. Hyperactivity on open field test, errors on rod bridge, and time reduction in inverted screen were detected at 15th, 19th, and 20th wpi respectively. Burrowing was more sensitive to earlier hippocampus dysfunction. However, Piry-infection did not significantly affect the already ongoing burrowing decline in the ME7-treated mice. After behavioral tests, brains were processed for IBA1, protease-resistant form of PrP, and Piry virus antigens. Although virus infection in isolation did not change the number of microglia in CA1, virus infection in prion diseased mice (at 17th wpi) induced changes in number and morphology of microglia in a laminar-dependent way. We suggest that virus infection exacerbates microglial inflammatory response to a greater degree in prion-infected mice, and this is not necessarily correlated with hippocampal-dependent behavioral deficits. PMID:28003864

Ticks associated with macquarie island penguins carry arboviruses from four genera.

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Lee Major

Full Text Available Macquarie Island, a small subantarctic island, is home to rockhopper, royal and king penguins, which are often infested with the globally distributed seabird tick, Ixodes uriae. A flavivirus, an orbivirus, a phlebovirus, and a nairovirus were isolated from these ticks and partial sequences obtained. The flavivirus was nearly identical to Gadgets Gully virus, isolated some 30 year previously, illustrating the remarkable genetic stability of this virus. The nearest relative to the orbivirus (for which we propose the name Sandy Bay virus was the Scottish Broadhaven virus, and provided only the second available sequences from the Great Island orbivirus serogroup. The phlebovirus (for which we propose the name Catch-me-cave virus and the previously isolated Precarious Point virus were distinct but related, with both showing homology with the Finnish Uukuniemi virus. These penguin viruses provided the second and third available sequences for the Uukuniemi group of phleboviruses. The nairovirus (for which we propose the name Finch Creek virus was shown to be related to the North American Tillamook virus, the Asian Hazara virus and Nairobi sheep disease virus. Macquarie Island penguins thus harbour arboviruses from at least four of the seven arbovirus-containing genera, with related viruses often found in the northern hemisphere.

Differential protein modulation in midguts of Aedes aegypti infected with chikungunya and dengue 2 viruses.

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Stéphane Tchankouo-Nguetcheu

Full Text Available BACKGROUND: Arthropod borne virus infections cause several emerging and resurgent infectious diseases. Among the diseases caused by arboviruses, dengue and chikungunya are responsible for a high rate of severe human diseases worldwide. The midgut of mosquitoes is the first barrier for pathogen transmission and is a target organ where arboviruses must replicate prior to infecting other organs. A proteomic approach was undertaken to characterize the key virus/vector interactions and host protein modifications that happen in the midgut for viral transmission to eventually take place. METHODOLOGY AND PRINCIPAL FINDINGS: Using a proteomics differential approach with two-Dimensional Differential in-Gel Electrophoresis (2D-DIGE, we defined the protein modulations in the midgut of Aedes aegypti that were triggered seven days after an oral infection (7 DPI with dengue 2 (DENV-2 and chikungunya (CHIKV viruses. Gel profile comparisons showed that the level of 18 proteins was modulated by DENV-2 only and 12 proteins were modulated by CHIKV only. Twenty proteins were regulated by both viruses in either similar or different ways. Both viruses caused an increase of proteins involved in the generation of reactive oxygen species, energy production, and carbohydrate and lipid metabolism. Midgut infection by DENV-2 and CHIKV triggered an antioxidant response. CHIKV infection produced an increase of proteins involved in detoxification. CONCLUSION/SIGNIFICANCE: Our study constitutes the first analysis of the protein response of Aedes aegypti's midgut infected with viruses belonging to different families. It shows that the differentially regulated proteins in response to viral infection include structural, redox, regulatory proteins, and enzymes for several metabolic pathways. Some of these proteins like antioxidant are probably involved in cell protection. On the other hand, we propose that the modulation of other proteins like transferrin, hsp60 and alpha

Microculture Plaque Neutralization Test for California Group Arboviruses

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Seawright, Gary L.; Harding, Gherry; Thomas, Frederick C.; Hanson, Robert P.

1974-01-01

A microculture plaque neutralization test is described for California-group arboviruses that is as precise and quantitative as the standard test conducted in 60-mm petri dishes. It was shown that there was no significant between-panel or between-day variation in determinations and that a single pipette could be used for all serum-dilution levels within a titration without inoculum carry-over effect. The experimental protocol and statistical methods used produce 50% neutralization end points that meet the assumptions of parametric statistics. This permits the power and versatility of the analysis of variance to be exploited in testing for treatment effects in serological and immunological studies with viruses. Images PMID:4216288

Presence of Autoimmune Antibody in Chikungunya Infection

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Wirach Maek-a-nantawat

2009-01-01

Full Text Available Chikungunya infection has recently re-emerged as an important arthropod-borne disease in Thailand. Recently, Southern Thailand was identified as a potentially endemic area for the chikungunya virus. Here, we report a case of severe musculoskeletal complication, presenting with muscle weakness and swelling of the limbs. During the investigation to exclude autoimmune muscular inflammation, high titers of antinuclear antibody were detected. This is the report of autoimmunity detection associated with an arbovirus infection. The symptoms can mimic autoimmune polymyositis disease, and the condition requires close monitoring before deciding to embark upon prolonged specific treatment with immunomodulators.

Chikungunya fever: CNS infection and pathologies of a re-emerging arbovirus.

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Das, Trina; Jaffar-Bandjee, Marie Christine; Hoarau, Jean Jacques; Krejbich Trotot, Pascale; Denizot, Melanie; Lee-Pat-Yuen, Ghislaine; Sahoo, Renubala; Guiraud, Pascale; Ramful, Duksha; Robin, Stephanie; Alessandri, Jean Luc; Gauzere, Bernard Alex; Gasque, Philippe

2010-06-01

Chikungunya virus (CHIKV) is transmitted by Aedes mosquitoes and causes an acute symptomatic illness with fever, skin rash, and incapacitating arthralgia, which can evolve into chronic rheumatoid arthritis in elderly patients. This is a tropical disease originally described in central/east Africa in the 1960s, but its 2004 re-emergence in Africa and rapid spread in lands in and around the Indian Ocean (Reunion island, India, Malaysia) as well as Europe (Italy) led to almost 6 million cases worldwide. The risk of importation and spreading diseases with long-term sequelae is even greater today given the global distribution of the vectors (including in the Americas), increased tourism and the apparent capacity of CHIKV to produce high levels of viremia (10(9)-10(12) virus/ml of blood) and new mutants. CHIKV-associated neuropathology was described early in the 1960s, but it is the unprecedented incidence rate in Indian Ocean areas with efficient clinical facilities that allowed a better description of cases with severe encephalitis, meningoencephalitis, peripheral neuropathies and deaths among newborns (mother-to-child infection), infants and elderly patients. Death rates following CHIKV infection were estimated at 1:1000 cases in la Reunion's outbreak. These clinical observations have been corroborated by experimental infection in several mouse models, leading to CNS pathologies. We further describe in this review the capacity of CHIKV to infect neurons and glial cells, delineate the fundamental innate (intrinsic) immune defence mechanisms to protect from infection and argue about the possible mechanisms involved in the encephalopathy. (c) 2010 Elsevier Ltd. All rights reserved.

Contemporary status of insecticide resistance in the major Aedes vectors of arboviruses infecting humans.

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Moyes, Catherine L; Vontas, John; Martins, Ademir J; Ng, Lee Ching; Koou, Sin Ying; Dusfour, Isabelle; Raghavendra, Kamaraju; Pinto, João; Corbel, Vincent; David, Jean-Philippe; Weetman, David

2017-07-01

Both Aedes aegytpi and Ae. albopictus are major vectors of 5 important arboviruses (namely chikungunya virus, dengue virus, Rift Valley fever virus, yellow fever virus, and Zika virus), making these mosquitoes an important factor in the worldwide burden of infectious disease. Vector control using insecticides coupled with larval source reduction is critical to control the transmission of these viruses to humans but is threatened by the emergence of insecticide resistance. Here, we review the available evidence for the geographical distribution of insecticide resistance in these 2 major vectors worldwide and map the data collated for the 4 main classes of neurotoxic insecticide (carbamates, organochlorines, organophosphates, and pyrethroids). Emerging resistance to all 4 of these insecticide classes has been detected in the Americas, Africa, and Asia. Target-site mutations and increased insecticide detoxification have both been linked to resistance in Ae. aegypti and Ae. albopictus but more work is required to further elucidate metabolic mechanisms and develop robust diagnostic assays. Geographical distributions are provided for the mechanisms that have been shown to be important to date. Estimating insecticide resistance in unsampled locations is hampered by a lack of standardisation in the diagnostic tools used and by a lack of data in a number of regions for both resistance phenotypes and genotypes. The need for increased sampling using standard methods is critical to tackle the issue of emerging insecticide resistance threatening human health. Specifically, diagnostic doses and well-characterised susceptible strains are needed for the full range of insecticides used to control Ae. aegypti and Ae. albopictus to standardise measurement of the resistant phenotype, and calibrated diagnostic assays are needed for the major mechanisms of resistance.

Contemporary status of insecticide resistance in the major Aedes vectors of arboviruses infecting humans

Science.gov (United States)

Vontas, John; Martins, Ademir J.; Ng, Lee Ching; Koou, Sin Ying; Dusfour, Isabelle; Raghavendra, Kamaraju; Pinto, João; Corbel, Vincent; David, Jean-Philippe; Weetman, David

2017-01-01

Both Aedes aegytpi and Ae. albopictus are major vectors of 5 important arboviruses (namely chikungunya virus, dengue virus, Rift Valley fever virus, yellow fever virus, and Zika virus), making these mosquitoes an important factor in the worldwide burden of infectious disease. Vector control using insecticides coupled with larval source reduction is critical to control the transmission of these viruses to humans but is threatened by the emergence of insecticide resistance. Here, we review the available evidence for the geographical distribution of insecticide resistance in these 2 major vectors worldwide and map the data collated for the 4 main classes of neurotoxic insecticide (carbamates, organochlorines, organophosphates, and pyrethroids). Emerging resistance to all 4 of these insecticide classes has been detected in the Americas, Africa, and Asia. Target-site mutations and increased insecticide detoxification have both been linked to resistance in Ae. aegypti and Ae. albopictus but more work is required to further elucidate metabolic mechanisms and develop robust diagnostic assays. Geographical distributions are provided for the mechanisms that have been shown to be important to date. Estimating insecticide resistance in unsampled locations is hampered by a lack of standardisation in the diagnostic tools used and by a lack of data in a number of regions for both resistance phenotypes and genotypes. The need for increased sampling using standard methods is critical to tackle the issue of emerging insecticide resistance threatening human health. Specifically, diagnostic doses and well-characterised susceptible strains are needed for the full range of insecticides used to control Ae. aegypti and Ae. albopictus to standardise measurement of the resistant phenotype, and calibrated diagnostic assays are needed for the major mechanisms of resistance. PMID:28727779

Contemporary status of insecticide resistance in the major Aedes vectors of arboviruses infecting humans.

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Catherine L Moyes

2017-07-01

Full Text Available Both Aedes aegytpi and Ae. albopictus are major vectors of 5 important arboviruses (namely chikungunya virus, dengue virus, Rift Valley fever virus, yellow fever virus, and Zika virus, making these mosquitoes an important factor in the worldwide burden of infectious disease. Vector control using insecticides coupled with larval source reduction is critical to control the transmission of these viruses to humans but is threatened by the emergence of insecticide resistance. Here, we review the available evidence for the geographical distribution of insecticide resistance in these 2 major vectors worldwide and map the data collated for the 4 main classes of neurotoxic insecticide (carbamates, organochlorines, organophosphates, and pyrethroids. Emerging resistance to all 4 of these insecticide classes has been detected in the Americas, Africa, and Asia. Target-site mutations and increased insecticide detoxification have both been linked to resistance in Ae. aegypti and Ae. albopictus but more work is required to further elucidate metabolic mechanisms and develop robust diagnostic assays. Geographical distributions are provided for the mechanisms that have been shown to be important to date. Estimating insecticide resistance in unsampled locations is hampered by a lack of standardisation in the diagnostic tools used and by a lack of data in a number of regions for both resistance phenotypes and genotypes. The need for increased sampling using standard methods is critical to tackle the issue of emerging insecticide resistance threatening human health. Specifically, diagnostic doses and well-characterised susceptible strains are needed for the full range of insecticides used to control Ae. aegypti and Ae. albopictus to standardise measurement of the resistant phenotype, and calibrated diagnostic assays are needed for the major mechanisms of resistance.

Mosquito-borne Arbovirus Surveillance at Selected Sites in Diverse Ecological Zones of Kenya 2007 -- 2012

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2013-05-10

and pooled (1 to 25 mosquitoes per pool) by species, sex and collection sites using mosquito identification keys by [23-26] and preserved in 1.5 ml...reference and research on arboviruses and haemorrhagic fever viruses. Dakar, Senegal: Institut Pasteur de Dakar; 2000. 8. Kalunda M, Lwanga-Ssozi C

Zika and Chikungunya virus detection in naturally infected Aedes aegypti in Ecuador.

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Cevallos, Varsovia; Ponce, Patricio; Waggoner, Jesse J; Pinsky, Benjamin A; Coloma, Josefina; Quiroga, Cristina; Morales, Diego; Cárdenas, Maria José

2018-01-01

The wide and rapid spread of Chikungunya (CHIKV) and Zika (ZIKV) viruses represent a global public health problem, especially for tropical and subtropical environments. The early detection of CHIKV and ZIKV in mosquitoes may help to understand the dynamics of the diseases in high-risk areas, and to design data based epidemiological surveillance to activate the preparedness and response of the public health system and vector control programs. This study was done to detect ZIKV and CHIKV viruses in naturally infected fed female Aedes aegypti (L.) mosquitoes from active epidemic urban areas in Ecuador. Pools (n=193; 22 pools) and individuals (n=22) of field collected Ae. aegypti mosquitoes from high-risk arboviruses infection sites in Ecuador were analyzed for the presence of CHIKV and ZIKV using RT-PCR. Phylogenetic analysis demonstrated that both ZIKV and CHIKV viruses circulating in Ecuador correspond to the Asian lineages. Minimum infection rate (MIR) of CHIKV for Esmeraldas city was 2.3% and the maximum likelihood estimation (MLE) was 3.3%. The minimum infection rate (MIR) of ZIKV for Portoviejo city was 5.3% and for Manta city was 2.1%. Maximum likelihood estimation (MLE) for Portoviejo city was 6.9% and 2.6% for Manta city. Detection of arboviruses and infection rates in the arthropod vectors may help to predict an outbreak and serve as a warning tool in surveillance programs. Copyright © 2017 Elsevier B.V. All rights reserved.

Emergent and Reemergent Arboviruses in South America and the Caribbean: Why So Many and Why Now?

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Marcondes, Carlos Brisola; Contigiani, Marta; Gleiser, Raquel Miranda

2017-05-01

Varios arbovirus han emergido y/o reemergido en el Nuevo Mundo en las últimas décadas. Los virus Zika y chikungunya, anteriormente restringidos a África y quizás Asia, invadieron el continente, causando gran preocupación; además siguen ocurriendo brotes causados por el virus dengue en casi todos los países, con millones de casos por año. El virus West Nile invadió rápidamente América del Norte, y ya se han encontrado casos en América Central y del Sur. Otros arbovirus, como Mayaro y el virus de la encefalitis equina del este han aumentado su actividad y se han encontrado en nuevas regiones. Se han documentado cambios en la patogenicidad de algunos virus que conducen a enfermedades inesperadas. Una fauna diversa de mosquitos, cambios climáticos y en la vegetación, aumento de los viajes, y urbanizaciones no planificadas que generan condiciones adecuadas para la proliferación de Aedes aegypti (L.), Culex quinquefasciatus Say y otros mosquitos vectores, se han combinado para influir fuertemente en los cambios en la distribución y la incidencia de varios arbovirus. Se enfatiza la necesidad de realizar estudios exhaustivos de la fauna de mosquitos y modificaciones de las condiciones ambientales, sobre todo en las zonas urbanas fuertemente influenciadas por factores sociales, políticos y económicos. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Dengue virus infection in renal allograft recipients: a case series during 2010 outbreak.

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Prasad, N; Bhadauria, D; Sharma, R K; Gupta, A; Kaul, A; Srivastava, A

2012-04-01

Dengue virus infection is an emerging global threat caused by Arbovirus, a virus from Flaviridiae family, which is transmitted by mosquitoes, Aedes aegypti and Aedes albopictus. Renal transplant recipients who live in the endemic zones of dengue infection or who travel to an endemic zone could be at risk of this infection. Despite multiple epidemics and a high case fatality rate in the Southeast Asian region, only a few cases of dengue infection in renal transplant recipients have been reported. Here, we report a case series of 8 dengue viral infection in renal transplant recipients. Of the 8 patients, 3 developed dengue hemorrhagic shock syndrome and died. © 2011 John Wiley & Sons A/S.

Restriction of Rift Valley Fever Virus Virulence in Mosquito Cells

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Sonja R. Gerrard

2010-02-01

Full Text Available Arboviruses are maintained in a natural cycle that requires blood-sucking arthropod and vertebrate hosts. Arboviruses are believed to persistently infect their arthropod host without overt pathology and cause acute infection with viremia in their vertebrate host. We have focused on elucidating how a specific arbovirus, Rift Valley fever (RVF virus, causes cytopathic effect in cells derived from vertebrates and non-cytopathic infection in cells derived from arthropods. We demonstrate that the vertebrate virulence factor, NSs, is functional in arthropod cells but is expressed at significantly lower levels in infected arthropod versus infected vertebrate cells.

Emerging arboviruses in Quebec, Canada: assessing public health risk by serology in humans, horses and pet dogs.

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Rocheleau, J P; Michel, P; Lindsay, L R; Drebot, M; Dibernardo, A; Ogden, N H; Fortin, A; Arsenault, J

2017-10-01

Periodic outbreaks of West Nile virus (WNV), Eastern equine encephalitis virus (EEEV) and to a lesser extent, California serogroup viruses (CSGV), have been reported in parts of Canada in the last decade. This study was designed to provide a broad assessment of arboviral activity in Quebec, Canada, by conducting serological surveys for these arboviruses in 196 horses, 1442 dogs and 485 humans. Sera were screened by a competitive enzyme linked immunosorbent assay and positive samples confirmed by plaque reduction neutralisation tests. The percentage of seropositive samples was 83·7%, 16·5%, 7·1% in horses, 18·8%, 0·6%, 0% in humans, 11·7%, 3·1%, 0% in adult dogs and 2·9%, 0·3%, 0% in juvenile dogs for CSGV, WNV and EEEV, respectively. Serological results in horses and dogs appeared to provide a meaningful assessment of risk to public health posed by multiple arboviruses.

Arboviral Etiologies of Acute Febrile Illnesses in Western South America, 2000–2007

Science.gov (United States)

Forshey, Brett M.; Guevara, Carolina; Laguna-Torres, V. Alberto; Cespedes, Manuel; Vargas, Jorge; Gianella, Alberto; Vallejo, Efrain; Madrid, César; Aguayo, Nicolas; Gotuzzo, Eduardo; Suarez, Victor; Morales, Ana Maria; Beingolea, Luis; Reyes, Nora; Perez, Juan; Negrete, Monica; Rocha, Claudio; Morrison, Amy C.; Russell, Kevin L.; J. Blair, Patrick; Olson, James G.; Kochel, Tadeusz J.

2010-01-01

Background Arthropod-borne viruses (arboviruses) are among the most common agents of human febrile illness worldwide and the most important emerging pathogens, causing multiple notable epidemics of human disease over recent decades. Despite the public health relevance, little is know about the geographic distribution, relative impact, and risk factors for arbovirus infection in many regions of the world. Our objectives were to describe the arboviruses associated with acute undifferentiated febrile illness in participating clinics in four countries in South America and to provide detailed epidemiological analysis of arbovirus infection in Iquitos, Peru, where more extensive monitoring was conducted. Methodology/Findings A clinic-based syndromic surveillance system was implemented in 13 locations in Ecuador, Peru, Bolivia, and Paraguay. Serum samples and demographic information were collected from febrile participants reporting to local health clinics or hospitals. Acute-phase sera were tested for viral infection by immunofluorescence assay or RT-PCR, while acute- and convalescent-phase sera were tested for pathogen-specific IgM by ELISA. Between May 2000 and December 2007, 20,880 participants were included in the study, with evidence for recent arbovirus infection detected for 6,793 (32.5%). Dengue viruses (Flavivirus) were the most common arbovirus infections, totaling 26.0% of febrile episodes, with DENV-3 as the most common serotype. Alphavirus (Venezuelan equine encephalitis virus [VEEV] and Mayaro virus [MAYV]) and Orthobunyavirus (Oropouche virus [OROV], Group C viruses, and Guaroa virus) infections were both observed in approximately 3% of febrile episodes. In Iquitos, risk factors for VEEV and MAYV infection included being male and reporting to a rural (vs urban) clinic. In contrast, OROV infection was similar between sexes and type of clinic. Conclusions/Significance Our data provide a better understanding of the geographic range of arboviruses in South

PIWIs Go Viral: Arbovirus-Derived piRNAs in Vector Mosquitoes.

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Pascal Miesen

2016-12-01

Full Text Available Vector mosquitoes are responsible for transmission of the majority of arthropod-borne (arbo- viruses. Virus replication in these vectors needs to be sufficiently high to permit efficient virus transfer to vertebrate hosts. The mosquito immune response therefore is a key determinant for arbovirus transmission. Mosquito antiviral immunity is primarily mediated by the small interfering RNA pathway. Besides this well-established antiviral machinery, the PIWI-interacting RNA (piRNA pathway processes viral RNA into piRNAs. In recent years, significant progress has been made in characterizing the biogenesis and function of these viral piRNAs. In this review, we discuss these developments, identify knowledge gaps, and suggest directions for future research.

Investigations into yellow fever virus and other arboviruses in the northern regions of Kenya.

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Henderson, B E; Metselaar, D; Kirya, G B; Timms, G L

1970-01-01

Previous studies having shown an appreciable level of yellow fever immunity to exist in northern Kenya, further epidemiological and serological surveys were carried out there in 1968 in an attempt to define more clearly the distribution of yellow fever and to locate possible vector and reservoir hosts of the disease; these surveys also provided information on a number of other arboviruses.Altogether 436 sera from 5 areas in northern Kenya were screened by haemagglutination-inhibition tests with 8 antigens, and 107 of these sera by neutralization tests for Group-B arboviruses. Small numbers of yellow-fever-immune adults were found in Ileret, Garissa, Loglogo and Mikona. At Marsabit high proportions of immune adults and children were found among the Burgi tribe. As the Burgi are permanent agricultural workers on Marsabit Mountain, an entomological investigation was made, over 15 000 mosquitos being collected. From these, 13 strains of Pongola virus, 1 strain of Semliki Forest virus and an unidentified virus were isolated, but no yellow fever strains. Aedes africanus and Aedes simpsoni were not found at Marsabit; small numbers of Aedes aegypti were collected biting man. The vector potential of other mosquitos collected (particularly Mansonia africana, which is present throughout the year) is discussed.

Behavioral, climatic, and environmental risk factors for Zika and Chikungunya virus infections in Rio de Janeiro, Brazil, 2015-16.

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Fuller, Trevon L; Calvet, Guilherme; Genaro Estevam, Camila; Rafael Angelo, Jussara; Abiodun, Gbenga J; Halai, Umme-Aiman; De Santis, Bianca; Carvalho Sequeira, Patricia; Machado Araujo, Eliane; Alves Sampaio, Simone; Lima de Mendonça, Marco Cesar; Fabri, Allison; Ribeiro, Rita Maria; Harrigan, Ryan; Smith, Thomas B; Raja Gabaglia, Claudia; Brasil, Patrícia; Bispo de Filippis, Ana Maria; Nielsen-Saines, Karin

2017-01-01

The burden of arboviruses in the Americas is high and may result in long-term sequelae with infants disabled by Zika virus infection (ZIKV) and arthritis caused by infection with Chikungunya virus (CHIKV). We aimed to identify environmental drivers of arbovirus epidemics to predict where the next epidemics will occur and prioritize municipalities for vector control and eventual vaccination. We screened sera and urine samples (n = 10,459) from residents of 48 municipalities in the state of Rio de Janeiro for CHIKV, dengue virus (DENV), and ZIKV by molecular PCR diagnostics. Further, we assessed the spatial pattern of arbovirus incidence at the municipal and neighborhood scales and the timing of epidemics and major rainfall events. Lab-confirmed cases included 1,717 infections with ZIKV (43.8%) and 2,170 with CHIKV (55.4%) and only 29 (<1%) with DENV. ZIKV incidence was greater in neighborhoods with little access to municipal water infrastructure (r = -0.47, p = 1.2x10-8). CHIKV incidence was weakly correlated with urbanization (r = 0.2, p = 0.02). Rains began in October 2015 and were followed one month later by the largest wave of ZIKV epidemic. ZIKV cases markedly declined in February 2016, which coincided with the start of a CHIKV outbreak. Rainfall predicted ZIKV and CHIKV with a lead time of 3 weeks each time. The association between rainfall and epidemics reflects vector ecology as the larval stages of Aedes aegypti require pools of water to develop. The temporal dynamics of ZIKV and CHIKV may be explained by the shorter incubation period of the viruses in the mosquito vector; 2 days for CHIKV versus 10 days for ZIKV.

Behavioral, climatic, and environmental risk factors for Zika and Chikungunya virus infections in Rio de Janeiro, Brazil, 2015-16.

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Trevon L Fuller

Full Text Available The burden of arboviruses in the Americas is high and may result in long-term sequelae with infants disabled by Zika virus infection (ZIKV and arthritis caused by infection with Chikungunya virus (CHIKV. We aimed to identify environmental drivers of arbovirus epidemics to predict where the next epidemics will occur and prioritize municipalities for vector control and eventual vaccination. We screened sera and urine samples (n = 10,459 from residents of 48 municipalities in the state of Rio de Janeiro for CHIKV, dengue virus (DENV, and ZIKV by molecular PCR diagnostics. Further, we assessed the spatial pattern of arbovirus incidence at the municipal and neighborhood scales and the timing of epidemics and major rainfall events. Lab-confirmed cases included 1,717 infections with ZIKV (43.8% and 2,170 with CHIKV (55.4% and only 29 (<1% with DENV. ZIKV incidence was greater in neighborhoods with little access to municipal water infrastructure (r = -0.47, p = 1.2x10-8. CHIKV incidence was weakly correlated with urbanization (r = 0.2, p = 0.02. Rains began in October 2015 and were followed one month later by the largest wave of ZIKV epidemic. ZIKV cases markedly declined in February 2016, which coincided with the start of a CHIKV outbreak. Rainfall predicted ZIKV and CHIKV with a lead time of 3 weeks each time. The association between rainfall and epidemics reflects vector ecology as the larval stages of Aedes aegypti require pools of water to develop. The temporal dynamics of ZIKV and CHIKV may be explained by the shorter incubation period of the viruses in the mosquito vector; 2 days for CHIKV versus 10 days for ZIKV.

Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs

NARCIS (Netherlands)

Miesen, P.; Ivens, A.; Buck, A.H.; Rij, R.P. van

2016-01-01

In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of

International workshop on insecticide resistance in vectors of arboviruses, December 2016, Rio de Janeiro, Brazil.

Science.gov (United States)

Corbel, Vincent; Fonseca, Dina M; Weetman, David; Pinto, João; Achee, Nicole L; Chandre, Fabrice; Coulibaly, Mamadou B; Dusfour, Isabelle; Grieco, John; Juntarajumnong, Waraporn; Lenhart, Audrey; Martins, Ademir J; Moyes, Catherine; Ng, Lee Ching; Raghavendra, Kamaraju; Vatandoost, Hassan; Vontas, John; Muller, Pie; Kasai, Shinji; Fouque, Florence; Velayudhan, Raman; Durot, Claire; David, Jean-Philippe

2017-06-02

Vector-borne diseases transmitted by insect vectors such as mosquitoes occur in over 100 countries and affect almost half of the world's population. Dengue is currently the most prevalent arboviral disease but chikungunya, Zika and yellow fever show increasing prevalence and severity. Vector control, mainly by the use of insecticides, play a key role in disease prevention but the use of the same chemicals for more than 40 years, together with the dissemination of mosquitoes by trade and environmental changes, resulted in the global spread of insecticide resistance. In this context, innovative tools and strategies for vector control, including the management of resistance, are urgently needed. This report summarizes the main outputs of the first international workshop on Insecticide resistance in vectors of arboviruses held in Rio de Janeiro, Brazil, 5-8 December 2016. The primary aims of this workshop were to identify strategies for the development and implementation of standardized insecticide resistance management, also to allow comparisons across nations and across time, and to define research priorities for control of vectors of arboviruses. The workshop brought together 163 participants from 28 nationalities and was accessible, live, through the web (> 70,000 web-accesses over 3 days).

Challenges for molecular and serological ZIKV infection confirmation.

Science.gov (United States)

de Vasconcelos, Zilton Farias Meira; Azevedo, Renata Campos; Thompson, Nathália; Gomes, Leonardo; Guida, Letícia; Moreira, Maria Elisabeth Lopes

2018-01-01

Zika Virus (ZIKV), member of Flaviviridae family and Flavivirus genus, has recently emerged as international public health emergency after its association with neonatal microcephaly cases. Clinical diagnosis hindrance involves symptom similarities produced by other arbovirus infections, therefore laboratory confirmation is of paramount importance. The most reliable test available is based on ZIKV RNA detection from body fluid samples. However, short viremia window periods and asymptomatic infections diminish the success rate for RT-PCR positivity. Beyond molecular detection, all serology tests in areas where other Flavivirus circulates proved to be a difficult task due to the broad range of cross-reactivity, especially with dengue pre-exposed individuals. Altogether, lack of serological diagnostic tools brings limitations to any retrospective evaluation. Those studies are central in the context of congenital infection that could occur asymptomatically and mask prevalence and risk rates.

Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses.

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Karel Van Roey

2014-12-01

Full Text Available Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the

Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses.

Science.gov (United States)

Van Roey, Karel; Sokny, Mao; Denis, Leen; Van den Broeck, Nick; Heng, Somony; Siv, Sovannaroth; Sluydts, Vincent; Sochantha, Tho; Coosemans, Marc; Durnez, Lies

2014-12-01

Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the epidemiological

Reabilitação psicológica de pacientes com seqüelas da encefalite por arbovirus Psychological rehabilitation of patients with sequelae due to encephalitis caused by arbovirus

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Anency Giannotti Hallage

1981-10-01

Full Text Available Foi investigado o possível comprometimento psíquico de pacientes com seqüelas da encefalite por arbovirus, do litoral sul do Estado de São Paulo (Brasil, com a finalidade de definir o papel do psicólogo, em um programa de reabilitação física e psicossocial. A presença das seqüelas era encarada de forma depreciativa e observou-se que essa percepção comprometeu fundamentalmente a identidade do paciente como ser humano, trazendo uma série de respostas emocionais desadaptadas e impossibibilitando a convivência satisfatória consigo e com o próximo. Os resultados analisados, em seu aspecto psicossociológico, revelaram que as dificuldades psíquicas observadas eram originárias da maneira como a deficiência física é encarada no meio social.The possibility of psychological damage in patients with sequelae from encephalitis caused by arbovirus in the southern section of the coastal area of the State of S. Paulo (Brazil was investigated for the purpose of defining the role of the psychologist in a programme of physical and psychosocial rehabilitation. The presence of the sequelae was regarded depreciatively by the patients and this attitude affected their self-regard as human beings. The result was a series of emotional maladjustments which made it impossible for the patients to live with themselves or maintain a satisfactory relationship with others. The results analyzed from a psychosocial standpoint revealed that the psychological problems observed arose from the way in which the physical deficiency is regarded within the social context.

Relationship between the prevalence of antibodies to arbovirus and hepatitis B virus in the Vale do Ribeira region, Brazil

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Cláudio Sérgio Pannuti

1989-04-01

Full Text Available 280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the periurban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and periurban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag was done through the radioimmunoassay (Ausab, Abbott Laboratory. The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche. A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36,1% when compared to those from the urban zone (5/89 = 5,6%, peri-urban (6/89 = 6,7% or from the cultivated zone (0/30 = 0%. The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region.

Relationship between the prevalence of antibodies to arbovirus and hepatitis B virus in the Vale do Ribeira region, Brazil.

Science.gov (United States)

Pannuti, C S; Iversson, L B; de Mendonça, J S; Travassos da Rosa, A P; Granato, C F

1989-01-01

280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the peri-urban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and peri-urban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag) was done through the radioimmunoassay (Ausab, Abbott Laboratory). The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche). A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36.1%) when compared to those from the urban zone (5/89 = 5.6%), peri-urban (6/89 = 6.7%) or from the cultivated zone (0/30 = 0%). The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region.

Seroprevalence of Infections with Dengue, Rift Valley Fever and Chikungunya Viruses in Kenya, 2007.

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Caroline Ochieng

Full Text Available Arthropod-borne viruses are a major constituent of emerging infectious diseases worldwide, but limited data are available on the prevalence, distribution, and risk factors for transmission in Kenya and East Africa. In this study, we used 1,091 HIV-negative blood specimens from the 2007 Kenya AIDS Indicator Survey (KAIS 2007 to test for the presence of IgG antibodies to dengue virus (DENV, chikungunya virus (CHIKV and Rift Valley fever virus (RVFV.The KAIS 2007 was a national population-based survey conducted by the Government of Kenya to provide comprehensive information needed to address the HIV/AIDS epidemic. Antibody testing for arboviruses was performed on stored blood specimens from KAIS 2007 through a two-step sandwich IgG ELISA using either commercially available kits or CDC-developed assays. Out of the 1,091 samples tested, 210 (19.2% were positive for IgG antibodies against at least one of the three arboviruses. DENV was the most common of the three viruses tested (12.5% positive, followed by RVFV and CHIKV (4.5% and 0.97%, respectively. For DENV and RVFV, the participant's province of residence was significantly associated (P≤.01 with seropositivity. Seroprevalence of DENV and RVFV increased with age, while there was no correlation between province of residence/age and seropositivity for CHIKV. Females had twelve times higher odds of exposure to CHIK as opposed to DENV and RVFV where both males and females had the same odds of exposure. Lack of education was significantly associated with a higher odds of previous infection with either DENV or RVFV (p <0.01. These data show that a number of people are at risk of arbovirus infections depending on their geographic location in Kenya and transmission of these pathogens is greater than previously appreciated. This poses a public health risk, especially for DENV.

Clinical and laboratory profile of different dengue sub types in dengue virus infection

OpenAIRE

Niloy Gan Chaudhuri; S. Vithyavathi; K. Sankar

2016-01-01

Background: Dengue infection, an arthropod-borne viral hemorrhagic fever is caused by Arbovirus of Flavivirus genus and transmitted by Aedes aegypti, Aedes albopictus. Liver involvement in dengue fever is manifested by the elevation of transaminases representing reactive hepatitis, due to direct attack of virus itself or the use of hepatotoxic drugs. The objective of the study was to investigate clinical and laboratory profile of different dengue sub type's patients admitted for dengue fever....

Arthropod-borne viral infections associated with a fever outbreak in the northern province of Sudan.

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Watts, D M; el-Tigani, A; Botros, B A; Salib, A W; Olson, J G; McCarthy, M; Ksiazek, T G

1994-08-01

An outbreak of acute febrile illness occurred during August and September 1989 in the Northern Province of Sudan coinciding with a high population density of phlebotomine sandflies. An investigation was conducted to determine whether arboviruses were associated with human illness during this outbreak. Sera were obtained from 185 febrile individuals and tested for IgG and IgM antibody to selected arboviruses by enzyme immunoassay (EIA). The prevalence of IgG antibody was 59% for West Nile (WN), 53% for Sandfly Fever Sicilian (SFS), 32% for Sandfly Fever Naples (SFN), 39% for Yellow Fever (YF), 24% for dengue-2 (DEN-2), 23% for Rift Valley Fever (RVF), 12% for Chikungunya (CHIK) and 5% for Crimean-Congo haemorrhagic Fever (CCHF) viruses. Antibody prevalences tended to increase with age for WN and YF viruses. Antibody rates were about the same for males and females for most of the viruses tested. The prevalence of IgM antibody to SFN was 24% and reciprocal IgM titre exceeded 12,800 for some individuals suggesting that this virus was the cause of recent infection. The prevalence of IgM antibody for the other viruses did not exceed 5%. The study indicated that several arboviruses were endemic and some of them may have caused human disease in the Northern Province of Sudan.

DEFEAT OF THE CARDIOVASCULAR SYSTEM IN VIRAL INFECTIONS

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E. V. Sharipova

2017-01-01

Full Text Available Article is devoted to studying of the submitted epidemiological, clinical, tool, laboratory data on pathology of cardiovascular system at various viral infections. The review is based on results of domestic and foreign researches. At viral infections damage of heart and his carrying-out system perhaps as during the sharp period of a disease, and the period of a convalescence or at the chronic course of virus process. The greatest cardiothrogenism is possessed by enteroviruses, which affect the myocardium in 5–15% of cases. Much attention is paid to herpesviruses, widespread, persistently persistent in the body, as one of the reasons for the development of dilated cardiomyopathy, coronary vasculitis, early atherosclerosis, cardiac rhythm disturbance. Other infections that may affect the cardiovascular system include influenza viruses, adenovirus, poliovirus, Epstein-Barr virus, cytomegalovirus, human immunodeficiency virus, hepatitis, mumps, rubella, herpes simplex, varicella, arbovirus, respiratory-syntial virus, yellow fever virus et al. Complications from cardiovascular system can come to light at various age.

Caracterização e relacionamento antigênico de três novos Bunyavirus no grupo Anopheles A (Bunyaviridae dos arbovirus

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Jorge Fernando Soares Travassos da Rosa

1992-06-01

Full Text Available São descritos o isolamento e a caracterização de três novos arbovirus isolados na região da Usina Hidro-Elétrica de Tucuruí (UHE-TUC. Os três novos arbovirus pertencem ao grupo Anopheles A(ANA, gênero Bunyavirus (família Bunyaviridae. Os vírus Tucuruí (TUC, Caraipé (CPE e Arumateua (ART são relacionados entre si e com o vírus Trombetas (TBT, formando dentro do grupo ANA um complexo chamado Trombetas. Os arbovirus TUC, CPE e ART foram obtidos a partir de lotes de mosquitos Anopheles (Nyssorhynchus sp capturados em Tucuruí, nas proximidades da usina hidrelétrica de Tucuruí, Estado do Pará, nos meses de fevereiro, agosto e outubro de 1984, respectivamente. Até o final de 1990 os vírus TUC, CPE e ART foram isolados 12, 32 e 28 vezes respectivamente, sempre na região da UHE-TUC, exceção feita ao vírus TUC, do qual se obteve uma amostra procedente de Balbina, onde também foi construída uma hidroelétrica. Até o presente, esses vírus só foram isolados a partir de mosquitos do grupo An. (Nys. principalmente, a partir das espécies An. (Nys. nuneztovari e An. (Nys. triannulatus também consideradas vetores secundários da malária na Amazônia Brasileira. Testes sorológicos executados com soros humanos e de diversas espécies de animais silvestres foram negativos, com exceção de um soro de um carnívoro de espécie Nasua nasua que neutralizou a amostra TUC em títulos de 2.6 índice logaritmico de neutralização (ILN.

Caracterização e relacionamento antigênico de três novos Bunyavirus no grupo Anopheles A (Bunyaviridae dos arbovirus

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Rosa Jorge Fernando Soares Travassos da

1992-01-01

Full Text Available São descritos o isolamento e a caracterização de três novos arbovirus isolados na região da Usina Hidro-Elétrica de Tucuruí (UHE-TUC. Os três novos arbovirus pertencem ao grupo Anopheles A(ANA, gênero Bunyavirus (família Bunyaviridae. Os vírus Tucuruí (TUC, Caraipé (CPE e Arumateua (ART são relacionados entre si e com o vírus Trombetas (TBT, formando dentro do grupo ANA um complexo chamado Trombetas. Os arbovirus TUC, CPE e ART foram obtidos a partir de lotes de mosquitos Anopheles (Nyssorhynchus sp capturados em Tucuruí, nas proximidades da usina hidrelétrica de Tucuruí, Estado do Pará, nos meses de fevereiro, agosto e outubro de 1984, respectivamente. Até o final de 1990 os vírus TUC, CPE e ART foram isolados 12, 32 e 28 vezes respectivamente, sempre na região da UHE-TUC, exceção feita ao vírus TUC, do qual se obteve uma amostra procedente de Balbina, onde também foi construída uma hidroelétrica. Até o presente, esses vírus só foram isolados a partir de mosquitos do grupo An. (Nys. principalmente, a partir das espécies An. (Nys. nuneztovari e An. (Nys. triannulatus também consideradas vetores secundários da malária na Amazônia Brasileira. Testes sorológicos executados com soros humanos e de diversas espécies de animais silvestres foram negativos, com exceção de um soro de um carnívoro de espécie Nasua nasua que neutralizou a amostra TUC em títulos de 2.6 índice logaritmico de neutralização (ILN.

Unraveling Host-Vector-Arbovirus Interactions by Two-Gene High Resolution Melting Mosquito Bloodmeal Analysis in a Kenyan Wildlife-Livestock Interface.

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David Omondi

Full Text Available The blood-feeding patterns of mosquitoes are directly linked to the spread of pathogens that they transmit. Efficient identification of arthropod vector bloodmeal hosts can identify the diversity of vertebrate species potentially involved in disease transmission cycles. While molecular bloodmeal analyses rely on sequencing of cytochrome b (cyt b or cytochrome oxidase 1 gene PCR products, recently developed bloodmeal host identification based on high resolution melting (HRM analyses of cyt b PCR products is more cost-effective. To resolve the diverse vertebrate hosts that mosquitoes may potentially feed on in sub-Saharan Africa, we utilized HRM profiles of both cyt b and 16S ribosomal RNA genes. Among 445 blood-fed Aedeomyia, Aedes, Anopheles, Culex, Mansonia, and Mimomyia mosquitoes from Kenya's Lake Victoria and Lake Baringo regions where many mosquito-transmitted pathogens are endemic, we identified 33 bloodmeal hosts including humans, eight domestic animal species, six peridomestic animal species and 18 wildlife species. This resolution of vertebrate host species was only possible by comparing profiles of both cyt b and 16S markers, as melting profiles of some pairs of species were similar for either marker but not both. We identified mixed bloodmeals in a Culex pipiens from Mbita that had fed on a goat and a human and in two Mansonia africana mosquitoes from Baringo that each had fed on a rodent (Arvicanthis niloticus in addition to a human or baboon. We further detected Sindbis and Bunyamwera viruses in blood-fed mosquito homogenates by Vero cell culture and RT-PCR in Culex, Aedeomyia, Anopheles and Mansonia mosquitoes from Baringo that had fed on humans and livestock. The observed mosquito feeding on both arbovirus amplifying hosts (including sheep and goats and possible arbovirus reservoirs (birds, porcupine, baboons, rodents informs arbovirus disease epidemiology and vector control strategies.

Dengue, Japanese encephalitis and Chikungunya virus antibody prevalence among captive monkey (Macaca nemestrina) colonies of Northern Thailand.

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Nakgoi, Khajornpong; Nitatpattana, Narong; Wajjwalku, Worawidh; Pongsopawijit, Pornsawan; Kaewchot, Supakarn; Yoksan, Sutee; Siripolwat, Voravit; Souris, Marc; Gonzalez, Jean-Paul

2014-01-01

The potential of macaque Macaca nemestrina leonina in Thailand to be infected by endemic arboviruses was assessed. The prevalence of antibodies of three arboviruses actively circulating in Thailand was determined by Plaque Reduction Neutralization assay procedures using samples from captive colonies in Northern Thailand. Out of 38 macaques, 9 (24%) presented reacting antibodies against dengue virus, 5 (13%) against Japanese encephalitis virus, and 4 (10%) against Chikungunya virus. Our results indicate that the northern pig-tailed macaque in Thailand can be infected by these arboviruses, inferring therefore that their virus specific vectors have bitten them. Given that, northern pig-tailed macaque represents an abundant population, living in close range to human or in peridomestic setting, they could play a role as potential reservoir host for arboviruses circulating in Thailand. © 2013 Wiley Periodicals, Inc.

Distribution and abundance of key vectors of Rift Valley fever and other arboviruses in two ecologically distinct counties in Kenya.

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Rosemary Sang

2017-02-01

Full Text Available Rift Valley fever (RVF is a mosquito-borne viral zoonosis of ruminants and humans that causes outbreaks in Africa and the Arabian Peninsula with significant public health and economic consequences. Humans become infected through mosquito bites and contact with infected livestock. The virus is maintained between outbreaks through vertically infected eggs of the primary vectors of Aedes species which emerge following rains with extensive flooding. Infected female mosquitoes initiate transmission among nearby animals, which amplifies virus, thereby infecting more mosquitoes and moving the virus beyond the initial point of emergence. With each successive outbreak, RVF has been found to expand its geographic distribution to new areas, possibly driven by available vectors. The aim of the present study was to determine if RVF virus (RVFV transmission risk in two different ecological zones in Kenya could be assessed by looking at the species composition, abundance and distribution of key primary and secondary vector species and the level of virus activity.Mosquitoes were trapped during short and long rainy seasons in 2014 and 2015 using CO2 baited CDC light traps in two counties which differ in RVF epidemic risk levels(high risk Tana-River and low risk Isiolo,cryo-preserved in liquid nitrogen, transported to the laboratory, and identified to species. Mosquito pools were analyzed for virus infection using cell culture screening and molecular analysis.Over 69,000 mosquitoes were sampled and identified as 40 different species belonging to 6 genera (Aedes, Anopheles, Mansonia, Culex, Aedeomyia, Coquillettidia. The presence and abundance of Aedes mcintoshi and Aedes ochraceus, the primary mosquito vectors associated with RVFV transmission in outbreaks, varied significantly between Tana-River and Isiolo. Ae. mcintoshi was abundant in Tana-River and Isiolo but notably, Aedes ochraceus found in relatively high numbers in Tana-River (n = 1,290, was totally

Dengue virus serotype 2 infection alters midgut and carcass gene expression in the Asian tiger mosquito, Aedes albopictus.

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Hitoshi Tsujimoto

Full Text Available The Asian tiger mosquito, Aedes albopictus is currently an important vector for dengue, chikungunya and Zika virus, and its role in transmission of arthropod-borne viruses (arboviruses may increase in the future due to its ability to colonize temperate regions. In contrast to Aedes aegypti, the dominant vector of dengue, chikungunya and Zika virus, genetic responses of Ae. albopictus upon infection with an arbovirus are not well characterized. Here we present a study of the changes in transcript expression in Ae. albopictus exposed to dengue virus serotype 2 via feeding on an artificial bloodmeal.We isolated midguts and midgut-free carcasses of Ae. albopictus fed on bloodmeals containing dengue virus as well as controls fed on virus-free control meals at day 1 and day 5 post-feeding. We confirmed infection of midguts from mosquitoes sampled on day 5 post-feeding via RT-PCR. RNAseq analysis revealed dynamic modulation of the expression of several putative immunity and dengue virus-responsive genes, some of whose expression was verified by qRT-PCR. For example, a serine protease gene was up-regulated in the midgut at 1 day post infection, which may potentially enhance mosquito susceptibility to dengue infection, while 14 leucine-rich repeat genes, previously shown to be involved in mosquito antiviral defenses, were down-regulated in the carcass at 5 days post infection. The number of significantly modulated genes decreased over time in midguts and increased in carcasses.Dengue virus exposure results in the modulation of genes in a time- and site-specific manner. Previous literature on the interaction between mosquitoes and mosquito-borne pathogens suggests that most of the changes that occurred in Ae. albopictus exposed to DENV would favor virus infection. Many genes identified in this study warrant further characterization to understand their role in viral manipulation of and antiviral response of Ae. albopictus.

Beware: It’s Mosquito Season (A Cup of Health with CDC)

Centers for Disease Control (CDC) Podcasts

West Nile virus and other arboviruses are transmitted primarily through the bite of an infected mosquito or tick. These viruses cause thousands of people to get sick each summer. In 2012, there was a substantial increase in the number of West Nile virus cases reported in the U.S. In this podcast, Jennifer Lehman discusses ways to avoid being infected with an arbovirus.

Real-time whole-body visualization of Chikungunya Virus infection and host interferon response in zebrafish.

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Nuno Palha

Full Text Available Chikungunya Virus (CHIKV, a re-emerging arbovirus that may cause severe disease, constitutes an important public health problem. Herein we describe a novel CHIKV infection model in zebrafish, where viral spread was live-imaged in the whole body up to cellular resolution. Infected cells emerged in various organs in one principal wave with a median appearance time of ∼14 hours post infection. Timing of infected cell death was organ dependent, leading to a shift of CHIKV localization towards the brain. As in mammals, CHIKV infection triggered a strong type-I interferon (IFN response, critical for survival. IFN was mainly expressed by neutrophils and hepatocytes. Cell type specific ablation experiments further demonstrated that neutrophils play a crucial, unexpected role in CHIKV containment. Altogether, our results show that the zebrafish represents a novel valuable model to dynamically visualize replication, pathogenesis and host responses to a human virus.

Cross reactivity of commercial anti-dengue immunoassays in patients with acute Zika virus infection.

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Felix, Alvina Clara; Souza, Nathalia C Santiago; Figueiredo, Walter M; Costa, Angela A; Inenami, Marta; da Silva, Rosangela M G; Levi, José Eduardo; Pannuti, Claudio Sergio; Romano, Camila Malta

2017-08-01

Several countries have local transmission of multiple arboviruses, in particular, dengue and Zika viruses, which have recently spread through many American countries. Cross reactivity among Flaviviruses is high and present a challenge for accurate identification of the infecting agent. Thus, we evaluated the level of cross reactivity of anti-dengue IgM/G Enzyme-Linked Immunosorbent Assays (ELISA) from three manufacturers against 122 serum samples obtained at two time-points from 61 patients with non-dengue confirmed Zika virus infection. All anti-dengue ELISAs cross reacted with serum from patients with acute Zika infection at some level and a worrisome number of seroconversion for dengue IgG and IgM was observed. These findings may impact the interpretation of currently standard criteria for dengue diagnosis in endemic regions. © 2017 Wiley Periodicals, Inc.

Viral and Antibody Kinetics, and Mosquito Infectivity of an Imported Case of Zika Fever Due to Asian Genotype (American Strain in Singapore

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Cheong Huat Tan

2018-01-01

Full Text Available We report a case of a Singaporean who acquired Zika virus (ZIKV during a visit to Cuba. The infection was confirmed using molecular and serological methods. This report highlights potential drawbacks of using IgG serology for diagnosis of flavivirus infections in endemic regions. The low viremia detected during the early phase of this case resulted in low mosquito infectivity rates, suggesting the possibility of ZIKV transmission prior to clinical onset. The report also emphasizes the challenges of public health interventions for Zika fever and the importance of sustaining a low vector population to reduce the risk of arbovirus transmission in vulnerable regions.

Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs.

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Miesen, Pascal; Ivens, Alasdair; Buck, Amy H; van Rij, Ronald P

2016-02-01

In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of the antiviral RNA interference machinery, one of the key pathways that limit virus replication in invertebrates. Besides siRNAs, Aedes mosquitoes and cells derived from these insects produce arbovirus-derived piRNAs, the best studied examples being viruses from the Togaviridae or Bunyaviridae families. Host miRNAs modulate the expression of a large number of genes and their levels may change in response to viral infections. In addition, some viruses, mostly with a DNA genome, express their own miRNAs to regulate host and viral gene expression. Here, we perform a comprehensive analysis of both viral and host-derived small RNAs in Aedes aegypti Aag2 cells infected with dengue virus 2 (DENV), a member of the Flaviviridae family. Aag2 cells are competent in producing all three types of small RNAs and provide a powerful tool to explore the crosstalk between arboviral infection and the distinct RNA silencing pathways. Interestingly, besides the well-characterized DENV-derived siRNAs, a specific population of viral piRNAs was identified in infected Aag2 cells. Knockdown of Piwi5, Ago3 and, to a lesser extent, Piwi6 results in reduction of vpiRNA levels, providing the first genetic evidence that Aedes PIWI proteins produce DENV-derived small RNAs. In contrast, we do not find convincing evidence for the production of virus-derived miRNAs. Neither do we find that host miRNA expression is strongly changed upon DENV2 infection. Finally, our deep-sequencing analyses detect 30 novel Aedes miRNAs, complementing the repertoire of regulatory small RNAs in this important vector species.

Infection by chikungunya virus modulates the expression of several proteins in Aedes aegypti salivary glands

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Tchankouo-Nguetcheu Stephane

2012-11-01

Full Text Available Abstract Background Arthropod-borne viral infections cause several emerging and resurging infectious diseases. Among the diseases caused by arboviruses, chikungunya is responsible for a high level of severe human disease worldwide. The salivary glands of mosquitoes are the last barrier before pathogen transmission. Methods We undertook a proteomic approach to characterize the key virus/vector interactions and host protein modifications that occur in the salivary glands that could be responsible for viral transmission by using quantitative two-dimensional electrophoresis. Results We defined the protein modulations in the salivary glands of Aedes aegypti that were triggered 3 and 5 days after an oral infection (3 and 5 DPI with chikungunya virus (CHIKV. Gel profile comparisons showed that CHIKV at 3 DPI modulated the level of 13 proteins, and at 5 DPI 20 proteins. The amount of 10 putatively secreted proteins was regulated at both time points. These proteins were implicated in blood-feeding or in immunity, but many have no known function. CHIKV also modulated the quantity of proteins involved in several metabolic pathways and in cell signalling. Conclusion Our study constitutes the first analysis of the protein response of Aedes aegypti salivary glands infected with CHIKV. We found that the differentially regulated proteins in response to viral infection include structural proteins and enzymes for several metabolic pathways. Some may favour virus survival, replication and transmission, suggesting a subversion of the insect cell metabolism by arboviruses. For example, proteins involved in blood-feeding such as the short D7, an adenosine deaminase and inosine-uridine preferring nucleoside hydrolase, may favour virus transmission by exerting an increased anti-inflammatory effect. This would allow the vector to bite without the bite being detected. Other proteins, like the anti-freeze protein, may support vector protection.

Genetic evidence for a worldwide chaotic dispersion pattern of the arbovirus vector, Aedes albopictus.

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Mosè Manni

2017-01-01

Full Text Available Invasive species represent a global concern for their rapid spread and the possibility of infectious disease transmission. This is the case of the global invader Aedes albopictus, the Asian tiger mosquito. This species is a vector of medically important arboviruses, notably chikungunya (CHIKV, dengue (DENV and Zika (ZIKV. The reconstruction of the complex colonization pattern of this mosquito has great potential for mitigating its spread and, consequently, disease risks.Classical population genetics analyses and Approximate Bayesian Computation (ABC approaches were combined to disentangle the demographic history of Aedes albopictus populations from representative countries in the Southeast Asian native range and in the recent and more recently colonized areas. In Southeast Asia, the low differentiation and the high co-ancestry values identified among China, Thailand and Japan indicate that, in the native range, these populations maintain high genetic connectivity, revealing their ancestral common origin. China appears to be the oldest population. Outside Southeast Asia, the invasion process in La Réunion, America and the Mediterranean Basin is primarily supported by a chaotic propagule distribution, which cooperates in maintaining a relatively high genetic diversity within the adventive populations.From our data, it appears that independent and also trans-continental introductions of Ae. albopictus may have facilitated the rapid establishment of adventive populations through admixture of unrelated genomes. As a consequence, a great amount of intra-population variability has been detected, and it is likely that this variability may extend to the genetic mechanisms controlling vector competence. Thus, in the context of the invasion process of this mosquito, it is possible that both population ancestry and admixture contribute to create the conditions for the efficient transmission of arboviruses and for outbreak establishment.

An Overview of Animal Models for Arthropod-Borne Viruses.

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Reynolds, Erin S; Hart, Charles E; Hermance, Meghan E; Brining, Douglas L; Thangamani, Saravanan

2017-06-01

Arthropod-borne viruses (arboviruses) have continued to emerge in recent years, posing a significant health threat to millions of people worldwide. The majority of arboviruses that are pathogenic to humans are transmitted by mosquitoes and ticks, but other types of arthropod vectors can also be involved in the transmission of these viruses. To alleviate the health burdens associated with arbovirus infections, it is necessary to focus today's research on disease control and therapeutic strategies. Animal models for arboviruses are valuable experimental tools that can shed light on the pathophysiology of infection and will enable the evaluation of future treatments and vaccine candidates. Ideally an animal model will closely mimic the disease manifestations observed in humans. In this review, we outline the currently available animal models for several viruses vectored by mosquitoes, ticks, and midges, for which there are no standardly available vaccines or therapeutics.

Arboviruses emerging in Brazil: challenges for clinic and implications for public health.

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Donalisio, Maria Rita; Freitas, André Ricardo Ribas; Zuben, Andrea Paula Bruno Von

2017-04-10

Arboviruses have been emerging in different parts of the world due to genetic changes in the virus, alteration of the host and vector population dynamics, or because of anthropogenic environmental factors. These viruses' capacity for adaptation is notable, as well as the likelihood of their emergence and establishment in new geographic areas. In Brazilian epidemiologic scenario, the most common arboviruses are DENV, CHIKV, and ZIKV, although others may spread in the country. Little is yet known of the impact of viral co-circulation, which would theoretically result in more intense viremia or other immunological alterations that could trigger autoimmune diseases, such as Guillain-Barré syndrome. The impact on morbidity and mortality intensifies as extensive epidemics lead to a high number of affected individuals, severe cases, and implications for health services, mainly due to the absence of treatment, vaccines, and effective prevention and control measures. RESUMO Notifica-se a emergência de arboviroses em diferentes regiões do planeta em decorrência de mudanças genéticas no vírus, alteração da dinâmica populacional de hospedeiros e vetores ou por fatores ambientais de origem antropogênica. É notável a capacidade de adaptação desses vírus e a possibilidade de emergirem e se estabelecerem em novas áreas geográficas. No contexto epidemiológico brasileiro, os arbovírus de maior circulação são DENV, CHIKV e ZIKV, embora existam outros com potencial de disseminação no País. O impacto da cocirculação viral ainda é pouco conhecido, a qual teoricamente resultaria em viremias mais intensas ou outras alterações imunológicas que poderiam ser o gatilho para doenças autoimunes, como a síndrome de Guillain-Barré. O impacto na morbidade e mortalidade se intensifica à medida que extensas epidemias pressupõem grande número de indivíduos acometidos, casos graves e implicações sobre os serviços de saúde, principalmente diante da aus

Strand-like structures and the nonstructural proteins 5, 3 and 1 are present in the nucleus of mosquito cells infected with dengue virus.

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Reyes-Ruiz, José M; Osuna-Ramos, Juan F; Cervantes-Salazar, Margot; Lagunes Guillen, Anel E; Chávez-Munguía, Bibiana; Salas-Benito, Juan S; Del Ángel, Rosa M

2018-02-01

Dengue virus (DENV) is an arbovirus, which replicates in the endoplasmic reticulum. Although replicative cycle takes place in the cytoplasm, some viral proteins such as NS5 and C are translocated to the nucleus during infection in mosquitoes and mammalian cells. To localized viral proteins in DENV-infected C6/36 cells, an immunofluorescence (IF) and immunoelectron microscopy (IEM) analysis were performed. Our results indicated that C, NS1, NS3 and NS5 proteins were found in the nucleus of DENV-infected C6/36 cells. Additionally, complex structures named strand-like structures (Ss) were observed in the nucleus of infected cells. Interestingly, the NS5 protein was located in these structures. Ss were absent in mock-infected cells, suggesting that DENV induces their formation in the nucleus of infected mosquito cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Dengue infection in the nervous system: lessons learned for Zika and Chikungunya

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Marzia Puccioni-Sohler

Full Text Available ABSTRACT Dengue, Zika and Chikungunya are emerging arboviruses and important causes of acute febrile disease in tropical areas. Although dengue does not represent a new condition, a geographic expansion over time has occurred with the appearance of severe neurological complications. Neglect has allowed the propagation of the vector (Aedes spp, which is also responsible for the transmission of other infections such as Zika and Chikungunya throughout the world. The increased number of infected individuals has contributed to the rise of neurological manifestations including encephalitis, myelitis, meningitis, Guillain-Barré syndrome and congenital malformations such as microcephaly. In this narrative review, we characterize the impact of the geographic expansion of the vector on the appearance of neurological complications, and highlight the lack of highly accurate laboratory tests for nervous system infections. This represents a challenge for public health in the world, considering the high number of travelers and people living in endemic areas.

Beware: It’s Mosquito Season (A Cup of Health with CDC)

Centers for Disease Control (CDC) Podcasts

2013-06-27

West Nile virus and other arboviruses are transmitted primarily through the bite of an infected mosquito or tick. These viruses cause thousands of people to get sick each summer. In 2012, there was a substantial increase in the number of West Nile virus cases reported in the U.S. In this podcast, Jennifer Lehman discusses ways to avoid being infected with an arbovirus.  Created: 6/27/2013 by MMWR.   Date Released: 6/27/2013.

Oviposition ecology and species composition of Aedes spp. and Aedes aegypti dynamics in variously urbanized settings in arbovirus foci in southeastern Côte d'Ivoire.

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Zahouli, Julien B Z; Utzinger, Jürg; Adja, Maurice A; Müller, Pie; Malone, David; Tano, Yao; Koudou, Benjamin G

2016-09-29

Aedes mosquito-transmitted outbreaks of dengue and yellow fever have been reported from rural and urban parts of Côte d'Ivoire. The present study aimed at assessing Aedes spp. oviposition ecology in variously urbanized settings within arbovirus foci in southeastern Côte d'Ivoire. Aedes spp. eggs were sampled using a standard ovitrap method from January 2013 to April 2014 in different ecosystems of rural, suburban and urban areas. Emerged larvae were reared until the adult stage for species identification. Aedes spp. oviposition ecology significantly varied from rural-to-urban areas and according to the ecozones and the seasons. Species richness of Aedes spp. gradually decreased from rural (eight species) to suburban (three species) and urban (one species) areas. Conversely, emerged adult Aedes spp. mean numbers were higher in the urban (1.97 Aedes/ovitrap/week), followed by the suburban (1.44 Aedes/ovitrap/week) and rural (0.89 Aedes/ovitrap/week) areas. Aedes aegypti was the only species in the urban setting (100 %), and was also the predominant species in suburban (85.5 %) and rural (63.3 %) areas. The highest Ae. aegypti mean number was observed in the urban (1.97 Ae. aegypti/ovitrap/week), followed by the suburban (1.20 Ae. aegypti/ovitrap/week) and rural (0.57 Ae. aegypti/ovitrap/week) areas. Aedes africanus (9.4 %), Ae. dendrophilus (8.0 %), Ae. metallicus (1.3 %) in the rural, and Ae. vittatus (6.5 %) and Ae. metallicus (1.2 %) in the suburban areas each represented more than 1 % of the total Aedes fauna. In all areas, Aedes species richness and abundance were higher in the peridomestic zones and during the rainy season, with stronger variations in species richness in the rural and in abundance in the urban areas. Besides, the highest Culex quinquefasciatus abundance was found in the urban areas, while Eretmapodites chrysogaster was restricted to the rural areas. Urbanization correlates with a substantially higher abundance in Aedes mosquitoes and

Screening of Blood Donations for Zika Virus Infection - Puerto Rico, April 3-June 11, 2016.

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Kuehnert, Matthew J; Basavaraju, Sridhar V; Moseley, Robin R; Pate, Lisa L; Galel, Susan A; Williamson, Phillip C; Busch, Michael P; Alsina, Jose O; Climent-Peris, Consuelo; Marks, Peter W; Epstein, Jay S; Nakhasi, Hira L; Hobson, J Peyton; Leiby, David A; Akolkar, Pradip N; Petersen, Lyle R; Rivera-Garcia, Brenda

2016-06-24

Transfusion-transmitted infections have been documented for several arboviruses, including West Nile and dengue viruses (1). Zika virus, a flavivirus transmitted primarily by Aedes aegypti mosquitoes that has been identified as a cause of congenital microcephaly and other serious brain defects (2), became recognized as a potential threat to blood safety after reports from a 2013-2014 outbreak in French Polynesia. Blood safety concerns were based on very high infection incidence in the population at large during epidemics, the high percentage of persons with asymptomatic infection, the high proportion of blood donations with evidence of Zika virus nucleic acid upon retrospective testing, and an estimated 7-10-day period of viremia (3). At least one instance of transfusion transmission of Zika virus has been documented in Brazil after the virus emerged there, likely in 2014 (4). Rapid epidemic spread has followed to other areas of the Americas, including Puerto Rico.

The role of gut bacteria in Schmallenberg virus transmission by Culicoides biting midges

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When an arbo-virus enters a vector it will first enter the gut system of this insect before entering cells of the insect body. Once in the gut-system, arbo-viruses and gut microbiota can interact with each other. We wondered if different gut bacterial communities could influence virus infection of b...

Management of Viral Central Nervous System Infections: A Primer for Clinicians

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P Brandon Bookstaver

2017-04-01

Full Text Available Viruses are a common cause of central nervous system (CNS infections with many host, agent, and environmental factors influencing the expression of viral diseases. Viruses can be responsible for CNS disease through a variety of mechanisms including direct infection and replication within the CNS resulting in encephalitis, infection limited to the meninges, or immune-related processes such as acute disseminated encephalomyelitis. Common pathogens including herpes simplex virus, varicella zoster, and enterovirus are responsible for the greatest number of cases in immunocompetent hosts. Other herpes viruses (eg, cytomegalovirus, John Cunningham virus are more common in immunocompromised hosts. Arboviruses such as Japanese encephalitis virus and Zika virus are important pathogens globally, but the prevalence varies significantly by geographic region and often season. Early diagnosis from radiographic evidence and molecular (eg, rapid diagnostics is important for targeted therapy. Antivirals may be used effectively against some pathogens, although several viruses have no effective treatment. This article provides a review of epidemiology, diagnostics, and management of common viral pathogens in CNS disease.

Serologic evidence of West Nile virus and Usutu virus infections in Eurasian coots in the Netherlands

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Lim, S.M.; Geervliet, M.; Verhagen, J.H.; Müskens, G.J.D.M.; Majoor, F.A.; Osterhaus, Albert D.M.E.; Martina, Byron E.

2018-01-01

West Nile virus (WNV) and Usutu virus (USUV) are arboviruses that are maintained in enzootic transmission cycles between mosquitoes and birds and are occasionally transmitted to mammals. As arboviruses are currently expanding their geographic range and emerging in often unpredictable locations,

Caracterização e relacionamento antigênico de três novos Bunyavirus no grupo Anopheles A (Bunyaviridae dos arbovirus Characterization and antigenic relationship of three new Bunyavirus in the Anopheles A serogroup (Bunyaviridae of arboviruses

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Jorge Fernando Soares Travassos da Rosa

1992-06-01

Full Text Available São descritos o isolamento e a caracterização de três novos arbovirus isolados na região da Usina Hidro-Elétrica de Tucuruí (UHE-TUC. Os três novos arbovirus pertencem ao grupo Anopheles A(ANA, gênero Bunyavirus (família Bunyaviridae. Os vírus Tucuruí (TUC, Caraipé (CPE e Arumateua (ART são relacionados entre si e com o vírus Trombetas (TBT, formando dentro do grupo ANA um complexo chamado Trombetas. Os arbovirus TUC, CPE e ART foram obtidos a partir de lotes de mosquitos Anopheles (Nyssorhynchus sp capturados em Tucuruí, nas proximidades da usina hidrelétrica de Tucuruí, Estado do Pará, nos meses de fevereiro, agosto e outubro de 1984, respectivamente. Até o final de 1990 os vírus TUC, CPE e ART foram isolados 12, 32 e 28 vezes respectivamente, sempre na região da UHE-TUC, exceção feita ao vírus TUC, do qual se obteve uma amostra procedente de Balbina, onde também foi construída uma hidroelétrica. Até o presente, esses vírus só foram isolados a partir de mosquitos do grupo An. (Nys. principalmente, a partir das espécies An. (Nys. nuneztovari e An. (Nys. triannulatus também consideradas vetores secundários da malária na Amazônia Brasileira. Testes sorológicos executados com soros humanos e de diversas espécies de animais silvestres foram negativos, com exceção de um soro de um carnívoro de espécie Nasua nasua que neutralizou a amostra TUC em títulos de 2.6 índice logaritmico de neutralização (ILN.The isolation and characterization of three new viruses obtained from the Tucuruí hydroelectric dam region is repeated. These three agents belong to the Anopheles A serogroup, genus Bunyavirus, Bunyaviridae. The Tucuruí (TUC, Caraipe (CPE and Arumateua (ART viruses have close relationships with each other and with Trombetas (TBT virus, an Anopheles A virus previously isolated in the Amazon Region of Brazil. These viruses form the "Trombetas complex". TUC, CPE and ART viruses were obtained from pools of

Aedes Mosquitoes and Aedes-Borne Arboviruses in Africa: Current and Future Threats

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Weetman, David; Shearer, Freya M.; Coulibaly, Mamadou

2018-01-01

The Zika crisis drew attention to the long-overlooked problem of arboviruses transmitted by Aedes mosquitoes in Africa. Yellow fever, dengue, chikungunya and Zika are poorly controlled in Africa and often go unrecognized. However, to combat these diseases, both in Africa and worldwide, it is crucial that this situation changes. Here, we review available data on the distribution of each disease in Africa, their Aedes vectors, transmission potential, and challenges and opportunities for Aedes control. Data on disease and vector ranges are sparse, and consequently maps of risk are uncertain. Issues such as genetic and ecological diversity, and opportunities for integration with malaria control, are primarily African; others such as ever-increasing urbanization, insecticide resistance and lack of evidence for most control-interventions reflect problems throughout the tropics. We identify key knowledge gaps and future research areas, and in particular, highlight the need to improve knowledge of the distributions of disease and major vectors, insecticide resistance, and to develop specific plans and capacity for arboviral disease surveillance, prevention and outbreak responses. PMID:29382107

POST-ENCEPHALITIC EPILEPSY AN ARBOVIRUS INFECTIONS IN AN ISOLATED RAIN-FOREST AREA OF CENTRAL LIBERIA

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van der Waals, F. W.; Asher, D. M.; Goudsmit, J.; Pomeroy, K. L.; Karabatsos, N.; Gajdusek, D. C.

1986-01-01

Among a population of 4.436 Bassa, Kpelle and Mano people in the Gbawein and Wroughbarh Clan region of Grand Bassa Country, Liberia, 123 cases of epilepsy could be documented. In 38% of these cases infections involving the central nervous system precipitated the onset of seizures. Sera from 67

Neuroimaging findings of congenital Zika virus infection: a pictorial essay.

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Zare Mehrjardi, Mohammad; Poretti, Andrea; Huisman, Thierry A G M; Werner, Heron; Keshavarz, Elham; Araujo Júnior, Edward

2017-03-01

Zika virus (ZIKV) is a mosquito-borne arbovirus from the Flaviviridae family. It had caused several epidemics since its discovery in 1947, but there was no significant attention to this virus until the recent outbreak in Brazil in 2015. The main concern is the causal relationship between prenatal ZIKV infection and congenital microcephaly, which has been confirmed recently. Moreover, ZIKV may cause other central nervous system abnormalities such as brain parenchymal atrophy with secondary ventriculomegaly, intracranial calcification, malformations of cortical development (such as polymicrogyria, and lissencephaly-pachygyria), agenesis/hypoplasia of the corpus callosum, cerebellar and brainstem hypoplasia, sensorineural hearing-loss, and ocular abnormalities as well as arthrogryposis in the infected fetuses. Postnatal (acquired) ZIKV infection usually has an asymptomatic or mildly symptomatic course, while prenatal (congenital) ZIKV infection has a more severe course and may cause severe brain anomalies that are described as congenital Zika syndrome. In this pictorial essay, we aim to illustrate the prenatal and postnatal neuroimaging findings that may be seen in fetuses and neonates with congenital Zika syndrome, and will discuss possible radiological differential diagnoses. A detailed knowledge of these findings is paramount for an early correct diagnosis, prognosis determination, and counseling of the affected children and families.

Inadequate management of natural ecosystem in the Brazilian Amazon region results in the emergence and reemergence of arboviruses Gestão imprópria do ecossistema natural na Amazônia brasileira resulta na emergência e reemergência de arbovírus

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Pedro F. C. Vasconcelos

2001-01-01

Full Text Available A total of 187 different species of arboviruses and other viruses in vertebrates were identified at the Evandro Chagas Institute (IEC from 1954 to 1998, among more than 10,000 arbovirus strains isolated from humans, hematophagous insects, and wild and sentinel vertebrates. Despite intensive studies in the Brazilian Amazon region, especially in Pará State, very little is known about most of these viruses, except for information on date, time, source, and method of isolation, as well as their capacity to infect laboratory animals. This paper reviews ecological and epidemiological data and analyzes the impact of vector and host population changes on various viruses as a result of profound changes in the natural environment. Deforestation, mining, dam and highway construction, human colonization, and urbanization were the main manmade environmental changes associated with the emergence and/or reemergence of relevant arboviruses, including some known pathogens for humans.Um total de 187 diferentes espécies de arbovírus, além de outros vírus de vertebrados, foram identificados pelo Instituto Evandro Chagas (IEC no período de 1954 a 1998, entre as mais de 10.000 cepas de vírus isoladas de seres humanos, insetos hematófagos e vertebrados-sentinela e silvestres. Apesar dos estudos intensivos realizados na Amazônia brasileira, sobretudo no Estado do Pará, pouco se sabe a respeito da maioria desses vírus, com exceção de dados a respeito de data, hora, fonte e método de isolamento, assim como a capacidade de infectar animais laboratoriais. Os autores fazem uma revisão dos dados ecológicos e epidemiológicos e procuram associar o impacto, sobre os diversos vírus, das mudanças populacionais dos vetores e hospedeiros induzidas por profundas alterações no meio ambiente. O desmatamento, o uso do subsolo, a construção de represas e de rodovias, a colonização humana e a urbanização foram as principais modificações ambientais

Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

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Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

2016-02-01

Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs.

Zika virus infection: Past and present of another emerging vector-borne disease.

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Sakkas, Hercules; Economou, Vangelis; Papadopoulou, Chrissanthy

2016-01-01

Zika virus infection is an emerging mosquito-borne disease, first identified in Uganda in 1947. It is caused by the Zika arbovirus, and transmitted by the bites of infected mosquitoes of the genus Aedes. For almost half a century, the Zika virus was reported as the causative agent of sporadic human infections. In 2007, the Zika virus emerged outside Asia and Africa causing an epidemic on the Island of Yap in Micronesia. The manifestation of the newly acquired human infection varies from asymptomatic to self-limiting acute febrile illness with symptoms and clinical features similar to those caused by the Dengue virus ('Dengue-like syndrome'). The real-time PCR and serological methods have been successfully applied for the diagnosis of the disease. The treatment is symptomatic, since there is no specific antiviral treatment or a vaccine. During the recent outbreaks in French Polynesia and Brazil, incidents of Guillain-Barrι syndrome and microcephaly were associated with Zika virus infection, giving rise to fears of further global spread of the virus. Prevention and vector control strategies have to be urgently implemented by national health authorities in order to contain future outbreaks in vulnerable populations. This review summarizes the existing information on Zika virus characteristics, pathogenesis and epidemiology, the available methods for the diagnosis of Zika virus infection and recent approaches for prevention and control.

FTA Cards Facilitate Storage, Shipment, and Detection of Arboviruses in Infected Aedes aegypti Collected in Adult Mosquito Traps.

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Hall-Mendelin, Sonja; Hewitson, Glen R; Genge, Doris; Burtonclay, Peter J; De Jong, Amanda J; Pyke, Alyssa T; van den Hurk, Andrew F

2017-05-01

AbstractThe utility of applying infected Aedes aegypti to Flinders Technology Associates (FTA ® ) cards for storage, transport, and detection of dengue, Zika, and Barmah Forest viruses was assessed in laboratory-based experiments. The mosquitoes had been removed from Gravid Aedes Traps maintained under conditions of high temperature and humidity. RNA of all viruses could be detected in infected mosquitoes on FTA cards either individually or in pools with uninfected mosquitoes, and stored for up to 28 days. Importantly, there was only a minimal decrease in RNA levels in mosquitoes between days 0 and 28, indicating that viral RNA was relatively stable on the cards. FTA cards thus provide a mechanism for storing potentially infected mosquitoes collected in the field and transporting them to a central diagnostic facility for virus detection.

Central Nervous System Effects of Intrauterine Zika Virus Infection: A Pictorial Review.

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Ribeiro, Bianca Guedes; Werner, Heron; Lopes, Flávia P P L; Hygino da Cruz, L Celso; Fazecas, Tatiana M; Daltro, Pedro A N; Nogueira, Renata A

2017-10-01

Relatively few agents have been associated with congenital infections involving the brain. One such agent is the Zika virus, which has caused several outbreaks worldwide and has spread in the Americas since 2015. The Zika virus is an arbovirus transmitted by infected female mosquito vectors, such as the Aedes aegypti mosquito. This virus has been commonly associated with congenital infections of the central nervous system and has greatly increased the rates of microcephaly. Ultrasonography (US) remains the method of choice for fetal evaluation of congenital Zika virus infection. For improved assessment of the extent of the lesions, US should be complemented by magnetic resonance (MR) imaging. Postnatal computed tomography and MR imaging can also unveil additional findings of central nervous system involvement, such as microcephaly with malformation of cortical development, ventriculomegaly, and multifocal calcifications in the cortical-subcortical junction, along with associated cortical atrophy. The calcifications may be punctate, dystrophic, linear, or coarse and may follow a predominantly bandlike distribution. A small anterior fontanelle with prematurely closed sutures is also observed with Zika virus infection. In this review, the prenatal and postnatal neurologic imaging findings of congenital Zika virus infection are covered. Radiologists must be aware of this challenging entity and have knowledge of the various patterns that may be depicted with each imaging modality and the main differential diagnosis of the disease. As in other neurologic infections, serial imaging is able to help demonstrate the progression of the findings. © RSNA, 2017.

[Yellow fever virus, dengue 2 and other arboviruses isolated from mosquitos, in Burkina Faso, from 1983 to 1986. Entomological and epidemiological considerations].

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Robert, V; Lhuillier, M; Meunier, D; Sarthou, J L; Monteny, N; Digoutte, J P; Cornet, M; Germain, M; Cordellier, R

1993-01-01

An arbovirus surveillance was carried out in Burkina Faso from 1983 to 1986. It was based on crepuscular catches of mosquitoes on human bait in some wooded areas and in one town. The total collection was 228 catches with an average of 8 men per catch. The total number of mosquitoes caught was 44,956 among which 32,010 potential vector of yellow fever; all these mosquitoes were analysed for arbovirology. In the south-western part of the country (region of Bobo-Dioulasso), surveillance was conducted each year from August to November, whilst the circulation of Aedes-borne arboviruses is well known to be favoured. In 1983, 1984 and 1986, seven strains of yellow fever virus were isolated in circumstances remarkably similar. They came from selvatic areas and never from the town. They concerned only Aedes (Stegomyia) luteocephalus which is the very predominant potential vector of yellow fever in the region. They were obtained in low figure, between 1 and 4 per year. They occurred from 27th of October to 21th of November. These observations confirm that the southern portion of the Sudan savanna zone of West Africa is the setting of a customary circulation of yellow fever virus and therefore belongs to the endemic emergence zone. In 1986, two strains of dengue 2 virus were isolated. One concerned Ae. luteocephalus from the selvatic area, the other Ae. (St.) aegypti from the heart of town. These data suggest two distinct cycles for dengue 2 virus, one urban and one selvatic, which could coexist simultaneously in the same region. In the south-eastern part of the country (region of Fada-N'Gourma) a yellow fever epidemic occurred between September and December 1983; its study has enable to precise their entomological aspects. The entomological inoculation rate of yellow fever virus has been evaluated to 22 infected bites per man during the month of october, for a man living close to forest gallery. 25 strains of yellow fever virus strains was isolated from Ae. (Diceromyia

Severe neutropenia revealing a rare presentation of dengue fever: a case report.

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Shourick, J; Dinh, A; Matt, M; Salomon, J; Davido, B

2017-08-17

Arboviruses are a common cause of fever in the returned traveler often associated with leucopenia, especially lymphopenia and thrombocytopenia. Transient neutropenia has been described in a few cases of arboviruses. However, prolonged and severe neutropenia (dengue fever, especially in the returned traveler in Europe. A 26-year-old healthy female without any medical past history, flying back from Thailand, presented a transient fever with severe neutropenia (dengue fever. Outcome was favorable without any antimicrobial therapy. Physicians should be wary of possible unusual presentation of dengue fever with prolonged neutropenia. Although such biological sign is more often associated with malaria or severe bacterial infection, it may be a sign of arbovirus.

The AWED trial (Applying Wolbachia to Eliminate Dengue) to assess the efficacy of Wolbachia-infected mosquito deployments to reduce dengue incidence in Yogyakarta, Indonesia: study protocol for a cluster randomised controlled trial.

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Anders, Katherine L; Indriani, Citra; Ahmad, Riris Andono; Tantowijoyo, Warsito; Arguni, Eggi; Andari, Bekti; Jewell, Nicholas P; Rances, Edwige; O'Neill, Scott L; Simmons, Cameron P; Utarini, Adi

2018-05-31

Dengue and other arboviruses transmitted by Aedes aegypti mosquitoes, including Zika and chikungunya, present an increasing public health challenge in tropical regions. Current vector control strategies have failed to curb disease transmission, but continue to be employed despite the absence of robust evidence for their effectiveness or optimal implementation. The World Mosquito Program has developed a novel approach to arbovirus control using Ae. aegypti stably transfected with Wolbachia bacterium, with a significantly reduced ability to transmit dengue, Zika and chikungunya in laboratory experiments. Modelling predicts this will translate to local elimination of dengue in most epidemiological settings. This study protocol describes the first trial to measure the efficacy of Wolbachia in reducing dengue virus transmission in the field. The study is a parallel, two-arm, non-blinded cluster randomised controlled trial conducted in a single site in Yogyakarta, Indonesia. The aim is to determine whether large-scale deployment of Wolbachia-infected Ae. aegypti mosquitoes leads to a measurable reduction in dengue incidence in treated versus untreated areas. The primary endpoint is symptomatic, virologically confirmed dengue virus infection of any severity. The 26 km 2 study area was subdivided into 24 contiguous clusters, allocated randomly 1:1 to receive Wolbachia deployments or no intervention. We use a novel epidemiological study design, the cluster-randomised test-negative design trial, in which dengue cases and arbovirus-negative controls are sampled concurrently from among febrile patients presenting to a network of primary care clinics, with case or control status classified retrospectively based on the results of laboratory diagnostic testing. Efficacy is estimated from the odds ratio of Wolbachia exposure distribution (probability of living in a Wolbachia-treated area) among virologically confirmed dengue cases compared to test-negative controls. A secondary

The Immune Responses of the Animal Hosts of West Nile Virus: A Comparison of Insects, Birds, and Mammals

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Laura R. H. Ahlers

2018-04-01

Full Text Available Vector-borne diseases, including arboviruses, pose a serious threat to public health worldwide. Arboviruses of the flavivirus genus, such as Zika virus (ZIKV, dengue virus, yellow fever virus (YFV, and West Nile virus (WNV, are transmitted to humans from insect vectors and can cause serious disease. In 2017, over 2,000 reported cases of WNV virus infection occurred in the United States, with two-thirds of cases classified as neuroinvasive. WNV transmission cycles through two different animal populations: birds and mosquitoes. Mammals, particularly humans and horses, can become infected through mosquito bites and represent dead-end hosts of WNV infection. Because WNV can infect diverse species, research on this arbovirus has investigated the host response in mosquitoes, birds, humans, and horses. With the growing geographical range of the WNV mosquito vector and increased human exposure, improved surveillance and treatment of the infection will enhance public health in areas where WNV is endemic. In this review, we survey the bionomics of mosquito species involved in Nearctic WNV transmission. Subsequently, we describe the known immune response pathways that counter WNV infection in insects, birds, and mammals, as well as the mechanisms known to curb viral infection. Moreover, we discuss the bacterium Wolbachia and its involvement in reducing flavivirus titer in insects. Finally, we highlight the similarities of the known immune pathways and identify potential targets for future studies aimed at improving antiviral therapeutic and vaccination design.

Measuring the burden of arboviral diseases: the spectrum of morbidity and mortality from four prevalent infections

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Bashir Fatima

2011-01-01

Full Text Available Abstract Background Globally, arthropod-borne virus infections are increasingly common causes of severe febrile disease that can progress to long-term physical or cognitive impairment or result in early death. Because of the large populations at risk, it has been suggested that these outcomes represent a substantial health deficit not captured by current global disease burden assessments. Methods We reviewed newly available data on disease incidence and outcomes to critically evaluate the disease burden (as measured by disability-adjusted life years, or DALYs caused by yellow fever virus (YFV, Japanese encephalitis virus (JEV, chikungunya virus (CHIKV, and Rift Valley fever virus (RVFV. We searched available literature and official reports on these viruses combined with the terms "outbreak(s," "complication(s," "disability," "quality of life," "DALY," and "QALY," focusing on reports since 2000. We screened 210 published studies, with 38 selected for inclusion. Data on average incidence, duration, age at onset, mortality, and severity of acute and chronic outcomes were used to create DALY estimates for 2005, using the approach of the current Global Burden of Disease framework. Results Given the limitations of available data, nondiscounted, unweighted DALYs attributable to YFV, JEV, CHIKV, and RVFV were estimated to fall between 300,000 and 5,000,000 for 2005. YFV was the most prevalent infection of the four viruses evaluated, although a higher proportion of the world's population lives in countries at risk for CHIKV and JEV. Early mortality and long-term, related chronic conditions provided the largest DALY components for each disease. The better known, short-term viral febrile syndromes caused by these viruses contributed relatively lower proportions of the overall DALY scores. Conclusions Limitations in health systems in endemic areas undoubtedly lead to underestimation of arbovirus incidence and related complications. However, improving

A geographical information system-based web model of arbovirus transmission risk in the continental United States of America

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Sarah K. Konrad

2012-11-01

Full Text Available A degree-day (DD model of West Nile virus capable of forecasting real-time transmission risk in the continental United States of America up to one week in advance using a 50-km grid is available online at https://sites. google.com/site/arbovirusmap/. Daily averages of historical risk based on temperatures for 1994-2003 are available at 10- km resolution. Transmission risk maps can be downloaded from 2010 to the present. The model can be adapted to work with any arbovirus for which the temperature-related parameters are known, e.g. Rift Valley fever virus. To more effectively assess virus establishment and transmission, the model incorporates “compound risk” maps and forecasts, which includes livestock density as a parameter.

First detection of natural infection of Aedes aegypti with Zika virus in Brazil and throughout South America

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Anielly Ferreira-de-Brito

Full Text Available Zika virus (ZIKV has caused a major epidemic in Brazil and several other American countries. ZIKV is an arbovirus whose natural vectors during epidemics have been poorly determined. In this study, 1,683 mosquitoes collected in the vicinity of ZIKV suspected cases in Rio de Janeiro, Brazil, from June 2015 to May 2016 were screened for natural infection by using molecular methods. Three pools of Aedes aegypti were found with the ZIKV genome, one of which had only one male. This finding supports the occurrence of vertical and/or venereal transmission of ZIKV in Ae. aegypti in nature. None of the examined Ae. albopictus and Culex quinquefasciatus was positive. This is the first report of natural infection by ZIKV in mosquitoes in Brazil and other South American countries. So far, Ae. aegypti is the only confirmed vector of ZIKV during the ongoing Pan-American epidemics.

Altered behavioral responses of Sindbis virus-infected Aedes aegypti (Diptera: Culicidae) to DEET and non-DEET based insect repellents.

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Qualls, Whitney A; Day, Jonathan F; Xue, Rui-de; Bowers, Doria F

2012-06-01

Changes in the time to first bite (TFB) and the bloodfeeding behavior of adult female Aedes aegypti (L.) mosquitoes following dissemination of Sindbis virus (SINV) were observed after exposure to repellents with the active ingredients (AI) DEET, picaridin, 2-undecanone (2-U), and oil of lemon eucalyptus. Dissemination of SINV significantly decreased (Ptimes were observed in SINV infected mosquitoes after exposure to the four repellents compared to uninfected mosquitoes. Taken together, a decrease in TFB and time to complete the four bloodfeeding stages will lessen the prey-status, and enhance both the chances of mosquito survival and arbovirus transmission. Published by Elsevier B.V.

Assessing likely invasion sites of Zika virus-infected mosquitoes in civilian and naval maritime ports in Florida

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Kollars TM

2017-01-01

Full Text Available Thomas M Kollars College of Health Sciences, Liberty University, Lynchburg, VA, USA Abstract: Several mosquito species are capable of invading new geographic regions and exploiting niches that are similar to their natural home ranges where they may introduce, or reintroduce, pathogens. In addition to initial invasion, introduction of new genotypes into established populations may also occur. Zika virus is spreading throughout the world, posing significant health risks to human populations, particularly pregnant women and their infants. The first locally acquired case of Zika virus in the US occurred in July 2016 in Miami, Florida on the Atlantic coast; the first locally acquired case in another US county occurred in the Tampa, Florida area. Three port cities in Florida were chosen to assess the risk of import and spread of Zika virus: Mayport Naval Station, Miami, and Tampa. The bioagent transport and enviromental modeling system TIGER model and ArcGIS were used to analyze abiotic and biotic factors influencing potentially Zika-infected Aedes species, should they enter through these ports. The model was tested by overlaying documented and suspected concurrent Zika cases and comparing published high-risk areas for Zika virus. In addition to Zika hot zones being identified, output indicates surveillance and integrated mosquito management should expect larger zones. Surveillance sites at ports should be identified and prioritized for pathogen and vector control to reduce the import of mosquitoes infected with Zika virus. Low resolution maps often provide valuable suitability of the geographic expansion of organisms. Providing a higher resolution predictive map, identifying probable routes of invasion, and providing areas at high risk for initial invasion and control zones, will aid in controlling and perhaps eliminating the spread of arboviruses through mosquito vectors. Keywords: Aedes, Zika virus, invasive species, maritime ports, biological

Viral RNA silencing suppression

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Hedil, Marcio; Kormelink, Richard

2016-01-01

The Bunyaviridae is a family of arboviruses including both plant-and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative

Aedes aegypti (Diptera: Culicidae) in Mauritania: First Report on the Presence of the Arbovirus Mosquito Vector in Nouakchott.

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Mint Lekweiry, Khadijetou; Ould Ahmedou Salem, Mohamed Salem; Ould Brahim, Khyarhoum; Ould Lemrabott, Mohamed Aly; Brengues, Cécile; Faye, Ousmane; Simard, Frédéric; Ould Mohamed Salem Boukhary, Ali

2015-07-01

Aedes aegypti L. (Diptera: Culicidae) is a major vector of yellow fever, dengue, and chikungunya viruses throughout tropical and subtropical areas of the world. Although the southernmost part of Mauritania along the Senegal river has long been recognized at risk of yellow fever transmission, Aedes spp. mosquitoes had never been reported northwards in Mauritania. Here, we report the first observation of Aedes aegypti aegypti (L.) and Aedes (Ochlerotatus) caspius (Pallas, 1771) in the capital city, Nouakchott. We describe the development sites in which larvae of the two species were found, drawing attention to the risk for emergence of arbovirus transmission in the city. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Changing haematological parameters in dengue viral infections

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Jamil, T.; Mehmood, K.; Mujtaba, G.; Choudhry, N.

2012-01-01

Background: Dengue Fever is the most common arboviral disease in the world, and presents cyclically in tropical and subtropical regions of the world. The four serotypes of dengue virus, 1, 2, 3, and 4, form an antigenic subgroup of the flaviviruses (Group B arboviruses). Transmission to humans of any of these serotypes initiates a spectrum of host responses, from in apparent to severe and sometimes lethal infections. Complete Blood count (CBC) is an important part of the diagnostic workup of patients. Comparison of various finding in CBC including peripheral smear can help the physician in better management of the patient. Material and Methods: This cross sectional study was carried out on a series of suspected patients of Dengue viral infection reporting in Ittefaq Hospital (Trust). All were investigated for serological markers of acute infection. Results Out of 341 acute cases 166 (48.7%) were confirmed by IgM against Dengue virus. IgG anti-dengue was used on 200 suspected re-infected patients. Seventy-one (39.5%) were positive and 118 (59%) were negative. Among 245 confirmed dengue fever patients 43 (17.6%) were considered having dengue hemorrhagic fever on the basis of lab and clinical findings. Raised haematocrit, Leukopenia with relative Lymphocytosis and presence atypical lymphocytes along with plasmacytoid cells was consistent finding at presentation in both the patterns of disease, i.e., Dengue Haemorrhagic fever (DHF) and Dengue fever (DF). Conclusion: Changes in relative percentage of cells appear with improvement in the symptoms and recovery from the disease. These findings indicate that in the course of the disease, there are major shifts within cellular component of blood. (author)

Testing for Zika virus infection in pregnancy: key concepts to deal with an emerging epidemic.

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Eppes, Catherine; Rac, Martha; Dunn, James; Versalovic, James; Murray, Kristy O; Suter, Melissa A; Sanz Cortes, Magda; Espinoza, Jimmy; Seferovic, Maxim D; Lee, Wesley; Hotez, Peter; Mastrobattista, Joan; Clark, Steven L; Belfort, Michael A; Aagaard, Kjersti M

2017-03-01

Zika virus is an emerging mosquito-borne (Aedes genus) arbovirus of the Flaviviridae family. Following epidemics in Micronesia and French Polynesia during the past decade, more recent Zika virus infection outbreaks were first reported in South America as early as May 2013 and spread to now 50 countries throughout the Americas. Although no other flavivirus has previously been known to cause major fetal malformations following perinatal infection, reports of a causal link between Zika virus and microcephaly, brain and ocular malformations, and fetal loss emerged from hard-hit regions of Brazil by October 2015. Among the minority of infected women with symptoms, clinical manifestations of Zika virus infection may include fever, headache, arthralgia, myalgia, and maculopapular rash; however, only 1 of every 4-5 people who are infected have any symptoms. Thus, clinical symptom reporting is an ineffective screening tool for the relative risk assessment of Zika virus infection in the majority of patients. As previously occurred with other largely asymptomatic viral infections posing perinatal transmission risk (such as HIV or cytomegalovirus), we must develop and implement rapid, sensitive, and specific screening and diagnostic testing for both viral detection and estimation of timing of exposure. Unfortunately, despite an unprecedented surge in attempts to rapidly advance perinatal clinical testing for a previously obscure arbovirus, there are several ongoing hindrances to molecular- and sonographic-based screening and diagnosis of congenital Zika virus infection. These include the following: (1) difficulty in estimating the timing of exposure for women living in endemic areas and thus limited interpretability of immunoglobulin M serologies; (2) cross-reaction of immunoglobulin serologies with other endemic flaviruses, such as dengue; (3) persistent viremia and viruria in pregnancy weeks to months after primary exposure; and (4) fetal brain malformations and anomalies

Zika Virus in the Male Reproductive Tract

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Liesel Stassen

2018-04-01

Full Text Available Arthropod-borne viruses (arboviruses are resurging across the globe. Zika virus (ZIKV has caused significant concern in recent years because it can lead to congenital malformations in babies and Guillain-Barré syndrome in adults. Unlike other arboviruses, ZIKV can be sexually transmitted and may persist in the male reproductive tract. There is limited information regarding the impact of ZIKV on male reproductive health and fertility. Understanding the mechanisms that underlie persistent ZIKV infections in men is critical to developing effective vaccines and therapies. Mouse and macaque models have begun to unravel the pathogenesis of ZIKV infection in the male reproductive tract, with the testes and prostate gland implicated as potential reservoirs for persistent ZIKV infection. Here, we summarize current knowledge regarding the pathogenesis of ZIKV in the male reproductive tract, the development of animal models to study ZIKV infection at this site, and prospects for vaccines and therapeutics against persistent ZIKV infection.

DENGUE, CHIKUNGUNYA AND ZIKA INFECTIONS IMPORTED TO PARIS BETWEEN 2009 AND 2016: CHARACTERISTICS AND CORRELATION WITH OUTBREAKS IN THE FRENCH OVERSEAS TERRITORIES OF GUADELOUPE AND MARTINIQUE.

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Vasquez, Victor; Haddad, Elie; Perignon, Alice; Jaureguiberry, Stéphane; Brichler, Ségolène; Leparc-Goffart, Isabelle; Caumes, Eric

2018-05-18

Dengue (DV), chikungunya (CV) and Zika virus (ZV) infections are rapidly expanding across countries and diagnosed in returned travelers who represent epidemiological sentinels. French Territories of America (FTA) such as Guadeloupe and Martinique are highly touristic places and have experienced three consecutive outbreaks by such viruses in the last decade. We evaluated how ill returned travelers could be deemed as epidemiological sentinels for these three expanding arboviral diseases during eight consecutive years. We estimated the degree of correlation between the cases of ill returned travelers arriving at our hospital and the three outbreaks that occurred in the FTA during the study period. We included all consecutive ill returned travelers diagnosed at a French tertiary hospital in Paris with imported DV, CV or ZV infections from January 2009 to December 2016. Epidemiological and clinical variables were evaluated. Data concerning the incidence of arboviruses in the FTA, and the temporal relationship between the occurrence of imported cases and outbreaks in FTA were analyzed. Overall, 320 cases of arboviral infections with 216 DV, 68 CV and 36 ZV were reported. Most of the patients presented with fever and exanthema. 115 patients were exposed in Guadeloupe or Martinique which were the at-risk destination in 25% of patients with DV, 59% patients with CV, and 58% patients with ZV. The occurrence of cases diagnosed in returning travelers followed the same time pattern as the outbreaks in these areas. We found a temporal correlation between newly diagnosed imported cases of arboviruses, and the three corresponding outbreaks that occurred in Martinique and Guadeloupe during 8 consecutive years. We show that ill returned travelers act as epidemiological sentinels from the beginning up to the end of outbreaks occurring in touristic places. Copyright © 2018. Published by Elsevier Ltd.

Preliminary investigation of Culicidae species in South Pantanal, Brazil and their potential importance in arbovirus transmission Investigação preliminar das espécies de culicídeos do Pantanal Sul brasileiro e sua potencial importância na transmissão de arbovírus

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Alex Pauvolid-Corrêa

2010-02-01

Full Text Available In view of the high circulation of migratory birds and the environmental and climatic conditions which favor the proliferation of arthropods, the Brazilian Pantanal is susceptible to circulation of arboviruses. However, the amount of data concerning arbovirus vectors in this area is scarce; therefore the aim of this study was to conduct a preliminary investigation of Culicidae species in the Nhecolândia Sub-region of South Pantanal, Brazil and their potential importance in the arbovirus transmission. A total of 3684 specimens of mosquitoes were captured, 1689 of which caught in the rainy season of 2007, were divided into 78 pools and submitted to viral isolation, Semi-Nested RT-PCR and Nested RT-PCR, with a view to identifying the most important arboviruses in Brazil. Simultaneously, 70 specimens of ticks found blood-feeding on horses were also submitted to the same virological assays. No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, a total of 22 Culicidae species were identified, ten of which had previously been reported as vectors of important arboviruses. The diversity of species found blood-feeding on human and horse hosts together with the arboviruses circulation previously reported suggest that the Nhecolândia Sub-region of South Pantanal is an important area for arbovirus surveillance in Brazil.Regiões como o Pantanal brasileiro, que apresentam fatores como riqueza de fauna silvestre incluindo circulação de aves migratórias e condições ambientais e climáticas favoráveis à proliferação de artrópodes estão potencialmente sujeitas à circulação de arbovírus. Entretanto, poucos trabalhos foram realizados acerca da presença de arbovírus em potenciais vetores no Pantanal. Neste sentido o principal objetivo deste trabalho foi conduzir uma investigação preliminar para presença de arbovírus em amostragens de culicídeos capturados na Sub-região da Nhecolândia no Pantanal

20 YEARS OF PROGRESS IN DENGUE HEMORRHAGIC FEVER AND OTHER ARBOVIRAL DISEASES RESEARCH

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Sumarmo Poorwo Soedarmo

2012-09-01

Full Text Available Throughout the 20 year history of U.S. Naval Medical Research Unit No. 2 Detachment (NAMRU, many viruses and viral diseases have been studied. The greatest emphasis has been in the field of arboviruses, specifically dengue virus, chikungunya virus, and Japanese B encephalitis virus. The initial focus of the work was to define the extent of the threat posed by these viruses. Studies were conducted to determine antibody prevalence, and to determine the etiologies of infectious febrile disease in hospitalized patients. Later the work advanced into more specific areas, especially the entomologic and clinical components of these viruses. Little was known of the incidence or kind of arbovirus infections in Indonesia when NAMRU was established. Previous serological studies had used the cross reactive haemagglutination assay. Green et al. in 1973 provided convincing serological evidence of infections with chikungunya virus and group B arboviruses by using the specific virus neutralization assay. These results demonstrated the need for further studies to isolate the causative agent, to describe the epidemiology, and to investigate the clinical features of the associated disease.

Identification of super-infected Aedes triseriatus mosquitoes collected as eggs from the field and partial characterization of the infecting La Crosse viruses

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Beaty Barry J

2010-04-01

Full Text Available Abstract Background La Crosse virus (LACV is a pathogenic arbovirus that is transovarially transmitted by Aedes triseriatus mosquitoes and overwinters in diapausing eggs. However, previous models predicted transovarial transmission (TOT to be insufficient to maintain LACV in nature. Results To investigate this issue, we reared mosquitoes from field-collected eggs and assayed adults individually for LACV antigen, viral RNA by RT-PCR, and infectious virus. The mosquitoes had three distinct infection phenotypes: 1 super infected (SI+ mosquitoes contained infectious virus, large accumulations of viral antigen and RNA and comprised 17 of 17,825 (0.09% of assayed mosquitoes, 2 infected mosquitoes (I+ contained no detectable infectious virus, lesser amounts of viral antigen and RNA, and comprised 3.7% of mosquitoes, and 3 non-infected mosquitoes (I- contained no detectable viral antigen, RNA, or infectious virus and comprised 96.21% of mosquitoes. SI+ mosquitoes were recovered in consecutive years at one field site, suggesting that lineages of TOT stably-infected and geographically isolated Ae. triseriatus exist in nature. Analyses of LACV genomes showed that SI+ isolates are not monophyletic nor phylogenetically distinct and that synonymous substitution rates exceed replacement rates in all genes and isolates. Analysis of singleton versus shared mutations (Fu and Li's F* revealed that the SI+ LACV M segment, with a large and significant excess of intermediate-frequency alleles, evolves through disruptive selection that maintains SI+ alleles at higher frequencies than the average mutation rate. A QTN in the LACV NSm gene was detected in SI+ mosquitoes, but not in I+ mosquitoes. Four amino acid changes were detected in the LACV NSm gene from SI+ but not I+ mosquitoes from one site, and may condition vector super infection. In contrast to NSm, the NSs sequences of LACV from SI+ and I+ mosquitoes were identical. Conclusions SI+ mosquitoes may represent

[Rift Valley fever: sporadic infection of French military personnel outside currently recognized epidemic zones].

Science.gov (United States)

Durand, J P; Richecoeur, L; Peyrefitte, C; Boutin, J P; Davoust, B; Zeller, H; Bouloy, M; Tolou, H

2002-01-01

For three years the arbovirus surveillance unit of the Tropical Medicine Institute of the French Army Medical Corps (French acronym IMTSSA) in Marseille, France has been investigating causes of benign non-malarial febrile syndromes in French military personnel serving outside mainland France. The methodology used in N'Djamena consisted of sending frozen specimens collected concomitant with viremia, to Marseille for culture. During the rainy season of 2001, specimens were collected from a total of 50 febrile soldiers. Cultures allowed isolation and identification of two strains of Rift Valley virus. The risk of contamination exists not only in the field but also in mainland hospital departments treating infected patients. Routine serological diagnosis for Rift Valley fever must be DISCUSSED for all patients in the field or returning from Africa.

Epidemiology of meningitis in an HIV-infected Ugandan cohort.

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Rajasingham, Radha; Rhein, Joshua; Klammer, Kate; Musubire, Abdu; Nabeta, Henry; Akampurira, Andrew; Mossel, Eric C; Williams, Darlisha A; Boxrud, Dave J; Crabtree, Mary B; Miller, Barry R; Rolfes, Melissa A; Tengsupakul, Supatida; Andama, Alfred O; Meya, David B; Boulware, David R

2015-02-01

There is limited understanding of the epidemiology of meningitis among human immunodeficiency virus (HIV)-infected populations in sub-Saharan Africa. We conducted a prospective cohort study of HIV-infected adults with suspected meningitis in Uganda, to comprehensively evaluate the etiologies of meningitis. Intensive cerebrospiral fluid (CSF) testing was performed to evaluate for bacterial, viral, fungal, and mycobacterial etiologies, including neurosyphilis,16s ribosomal DNA (rDNA) polymerase chain reaction (PCR) for bacteria, Plex-ID broad viral assay, quantitative-PCR for HSV-1/2, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Toxoplasma gondii; reverse transcription-PCR (RT-PCR) for Enteroviruses and arboviruses, and Xpert MTB/RIF assay. Cryptococcal meningitis accounted for 60% (188 of 314) of all causes of meningitis. Of 117 samples sent for viral PCR, 36% were EBV positive. Among cryptococcal antigen negative patients, the yield of Xpert MTB/RIF assay was 22% (8 of 36). After exclusion of cryptococcosis and bacterial meningitis, 61% (43 of 71) with an abnormal CSF profile had no definitive diagnosis. Exploration of new TB diagnostics and diagnostic algorithms for evaluation of meningitis in resource-limited settings remains needed, and implementation of cryptococcal diagnostics is critical. © The American Society of Tropical Medicine and Hygiene.

Mosquito bottlenecks alter viral mutant swarm in a tissue and time-dependent manner with contraction and expansion of variant positions and diversity.

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Patterson, Edward I; Khanipov, Kamil; Rojas, Mark M; Kautz, Tiffany F; Rockx-Brouwer, Dedeke; Golovko, Georgiy; Albayrak, Levent; Fofanov, Yuriy; Forrester, Naomi L

2018-01-01

Viral diversity is theorized to play a significant role during virus infections, particularly for arthropod-borne viruses (arboviruses) that must infect both vertebrate and invertebrate hosts. To determine how viral diversity influences mosquito infection and dissemination Culex taeniopus mosquitoes were infected with the Venezuelan equine encephalitis virus endemic strain 68U201. Bodies and legs/wings of the mosquitoes were collected individually and subjected to multi-parallel sequencing. Virus sequence diversity was calculated for each tissue. Greater diversity was seen in mosquitoes with successful dissemination versus those with no dissemination. Diversity across time revealed that bottlenecks influence diversity following dissemination to the legs/wings, but levels of diversity are restored by Day 12 post-dissemination. Specific minority variants were repeatedly identified across the mosquito cohort, some in nearly every tissue and time point, suggesting that certain variants are important in mosquito infection and dissemination. This study demonstrates that the interaction between the mosquito and the virus results in changes in diversity and the mutational spectrum and may be essential for successful transition of the bottlenecks associated with arbovirus infection.

Co-Infection of Mosquitoes with Chikungunya and Dengue Viruses Reveals Modulation of the Replication of Both Viruses in Midguts and Salivary Glands of Aedes aegypti Mosquitoes.

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Le Coupanec, Alain; Tchankouo-Nguetcheu, Stéphane; Roux, Pascal; Khun, Huot; Huerre, Michel; Morales-Vargas, Ronald; Enguehard, Margot; Lavillette, Dimitri; Missé, Dorothée; Choumet, Valérie

2017-08-04

Arthropod-borne virus (arbovirus) infections cause several emerging and resurgent infectious diseases in humans and animals. Chikungunya-affected areas often overlap with dengue-endemic areas. Concurrent dengue virus (DENV) and chikungunya virus (CHIKV) infections have been detected in travelers returning from regions of endemicity. CHIKV and DENV co-infected Aedes albopictus have also been collected in the vicinity of co-infected human cases, emphasizing the need to study co-infections in mosquitoes. We thus aimed to study the pathogen-pathogen interaction involved in these co-infections in DENV/CHIKV co-infected Aedes aegypti mosquitoes. In mono-infections, we detected CHIKV antigens as early as 4 days post-virus exposure in both the midgut (MG) and salivary gland (SG), whereas we detected DENV serotype 2 (DENV-2) antigens from day 5 post-virus exposure in MG and day 10 post-virus exposure in SG. Identical infection rates were observed for singly and co-infected mosquitoes, and facilitation of the replication of both viruses at various times post-viral exposure. We observed a higher replication for DENV-2 in SG of co-infected mosquitoes. We showed that mixed CHIKV and DENV infection facilitated viral replication in Ae. aegypti . The outcome of these mixed infections must be further studied to increase our understanding of pathogen-pathogen interactions in host cells.

Seasonal abundance and molecular identification of West Nile virus ...

African Journals Online (AJOL)

Seasonal abundance and molecular identification of West Nile virus vectors, Culex pipens and Culex ... Background: West Nile virus (WNV) infection, is an arbovirus infection with high morbidity and mortality, the vector respon- sible for both human ... Major diseases transmitted are known as Arboviral dis- eases because ...

The wMel strain of Wolbachia Reduces Transmission of Zika virus by Aedes aegypti.

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Aliota, Matthew T; Peinado, Stephen A; Velez, Ivan Dario; Osorio, Jorge E

2016-07-01

Zika virus (ZIKV) is causing an explosive outbreak of febrile disease in the Americas. There are no effective antiviral therapies or licensed vaccines for this virus, and mosquito control strategies have not been adequate to contain the virus. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against other arboviruses. At present, it is unknown whether or not ZIKV can infect, disseminate, and be transmitted by Wolbachia-infected Ae. aegypti. Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for ZIKV. These results support the use of Wolbachia biocontrol as a multivalent strategy against Ae. aegypti-transmitted viruses.

Dengue virus type 2 infections of Aedes aegypti are modulated by the mosquito's RNA interference pathway.

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Irma Sánchez-Vargas

2009-02-01

Full Text Available A number of studies have shown that both innate and adaptive immune defense mechanisms greatly influence the course of human dengue virus (DENV infections, but little is known about the innate immune response of the mosquito vector Aedes aegypti to arbovirus infection. We present evidence here that a major component of the mosquito innate immune response, RNA interference (RNAi, is an important modulator of mosquito infections. The RNAi response is triggered by double-stranded RNA (dsRNA, which occurs in the cytoplasm as a result of positive-sense RNA virus infection, leading to production of small interfering RNAs (siRNAs. These siRNAs are instrumental in degradation of viral mRNA with sequence homology to the dsRNA trigger and thereby inhibition of virus replication. We show that although dengue virus type 2 (DENV2 infection of Ae. aegypti cultured cells and oral infection of adult mosquitoes generated dsRNA and production of DENV2-specific siRNAs, virus replication and release of infectious virus persisted, suggesting viral circumvention of RNAi. We also show that DENV2 does not completely evade RNAi, since impairing the pathway by silencing expression of dcr2, r2d2, or ago2, genes encoding important sensor and effector proteins in the RNAi pathway, increased virus replication in the vector and decreased the extrinsic incubation period required for virus transmission. Our findings indicate a major role for RNAi as a determinant of DENV transmission by Ae. aegypti.

Prevalence of Guillain-Barré syndrome among Zika virus infected cases: a systematic review and meta-analysis

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Ludovica Barbi

2018-03-01

Full Text Available Zika virus (ZIKV is an emergent flavivirus transmitted mainly through Aedes spp. mosquitoes that is posing challenge to healthcare services in countries experiencing an outbreak. Usually ZIKV infection is mild, but in some cases it has been reported to progress into neurological diseases such as microcephaly in infants and Guillain-Barré syndrome (GBS in adults. GBS is a debilitating autoimmune disorder that affects peripheral nerves. Since ZIKV caused massive outbreaks in South America in the past few years, we aimed to systematically review the literature and perform a meta-analysis to estimate the prevalence of GBS among ZIKV-infected individuals. We searched PubMed and Cochrane databases and selected three studies for a meta-analysis. We estimated the prevalence of ZIKV-associated GBS to be 1.23% (95% CI = 1.17–1.29%. Limitations include paucity of data regarding previous flavivirus infections and ZIKV-infection confirmation issues. Our estimate seems to be low, but cannot be ignored, since ZIKV outbreaks affects an overwhelming number of individuals and GBS is a life-threatening debilitating condition, especially in pregnant women. ZIKV infection cases must be closely followed to assure prompt care to reduce the impact of GBS associated-sequelae on the quality of life of those affected. Keywords: Arboviruses, Zika virus, Guillain-Barré syndrome, Epidemiology, Emergent diseases

Homogeneity of Powassan virus populations in naturally infected Ixodes scapularis

International Nuclear Information System (INIS)

Brackney, Doug E.; Brown, Ivy K.; Nofchissey, Robert A.; Fitzpatrick, Kelly A.; Ebel, Gregory D.

2010-01-01

Powassan virus (POWV, Flaviviridae: Flavivirus) is the sole North American member of the tick-borne encephalitis complex and consists of two distinct lineages that are maintained in ecologically discrete enzootic transmission cycles. The underlying genetic mechanisms that lead to niche partitioning in arboviruses are poorly understood. Therefore, intra- and interhost genetic diversity was analyzed to determine if POWV exists as a quasispecies in nature and quantify selective pressures within and between hosts. In contrast to previous reports for West Nile virus (WNV), significant intrahost genetic diversity was not observed. However, pN (0.238) and d N /d S ratios (0.092) for interhost diversity were similar to those of WNV. Combined, these data suggest that purifying selection and/or population bottlenecks constrain quasispecies diversity within ticks. These same selective and stochastic mechanisms appear to drive minor sequence changes between ticks. Moreover, Powassan virus populations seem not to be structured as quasispecies in naturally infected adult deer ticks.

Climate Change and the Arboviruses: Lessons from the Evolution of the Dengue and Yellow Fever Viruses.

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Tabachnick, Walter J

2016-09-29

The impact of anticipated changes in global climate on the arboviruses and the diseases they cause poses a significant challenge for public health. The past evolution of the dengue and yellow fever viruses provides clues about the influence of changes in climate on their future evolution. The evolution of both viruses has been influenced by virus interactions involving the mosquito species and the primate hosts involved in virus transmission, and by their domestic and sylvatic cycles. Information is needed on how viral genes in general influence phenotypic variance for important viral functions. Changes in global climate will alter the interactions of mosquito species with their primate hosts and with the viruses in domestic cycles, and greater attention should be paid to the sylvatic cycles. There is great danger for the evolution of novel viruses, such as new serotypes, that could compromise vaccination programs and jeopardize public health. It is essential to understand (a) both sylvatic and domestic cycles and (b) the role of virus genetic and environmental variances in shaping virus phenotypic variance to more fully assess the impact of global climate change.

Inflammation of the external ear in acute chikungunya infection: Experience from the outbreak in Johor Bahru, Malaysia, 2008.

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Javelle, Emilie; Tiong, Tee Hua; Leparc-Goffart, Isabelle; Savini, Hélène; Simon, Fabrice

2014-04-01

The re-emerging invalidating chikungunya disease has recently extended to temperate areas. Other alphaviruses can also present with febrile arthalgias. Dengue virus transmitted by the same species of mosquitoes may cocirculate, leading to dual infections and concurrent epidemics. Although these diseases share similar clinical features, their prognoses considerably differ. Prominent and prolonged articular disorders are more consistent with chikungunya virus, whereas haemorrhages make the gravity of dengue infection. Specific symptoms are required, especially when diagnostic tests are not available or performable at a large scale. Indeed, early clinical suspicion of a vector-borne disease is crucial to isolate the first cases in the course of an outbreak, and discrimination between arboviruses help to optimal management of patients. No specific chikungunya clinical sign has been yet reported. We highlight here the high prevalence (about 25%) of acute ear redness in infected people during the 2008 chikungunya outbreak in Jahor Bahru in Malaysia. Nine consenting patients are more precisely described. Ear chondritis could be sensitive diagnostic criterion of the acute stage of chikungunya, every physician - even in occidental non endemic areas - should be aware of. Copyright © 2014 Elsevier B.V. All rights reserved.

Seroprevalence and distribution of arboviral infections among rural Kenyan adults: A cross-sectional study

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Schoepp Randal J

2011-07-01

Full Text Available Abstract Background Arthorpod-borne viruses (arboviruses cause wide-spread morbidity in sub-Saharan Africa, but little research has documented the burden and distribution of these pathogens. Methods Using a population-based, cross-sectional study design, we administered a detailed questionnaire and used ELISA to test the blood of 1,141 healthy Kenyan adults from three districts for the presence of anti-viral Immunoglobulin G (IgG antibodies to the following viruses: dengue (DENV, West Nile (WNV, yellow fever (YFV, Chikungunya (CHIKV, and Rift Valley fever (RVFV. Results Of these, 14.4% were positive for DENV, 9.5% were WNV positive, 9.2% were YFV positive, 34.0% were positive for CHIKV and 0.7% were RVFV positive. In total, 46.6% had antibodies to at least one of these arboviruses. Conclusions For all arboviruses, district of residence was strongly associated with seropositivity. Seroprevalence to YFV, DENV and WNV increased with age, while there was no correlation between age and seropositivity for CHIKV, suggesting that much of the seropositivity to CHIKV is due to sporadic epidemics. Paradoxically, literacy was associated with increased seropositivity of CHIKV and DENV.

Serologic survey for selected arboviruses and other potential pathogens in wildlife from Mexico.

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Aguirre, A A; McLean, R G; Cook, R S; Quan, T J

1992-07-01

During 1988 and 1989, a serologic survey of wildlife was conducted in northeastern Mexico to determine the presence, prevalence, and distribution of arboviruses and other selected disease agents. Eighty mammal specimens were tested. Antibodies to vesicular stomatitis-Indiana, Venezuelan equine encephalitis-Mena II, Rio Grande virus, and vesicular stomatitis-New Jersey were detected predominantly in small mammals. Deer and mouflon (Ovis musimon) had antibodies to bluetongue and epizootic hemorrhagic disease. Two species had serologic evidence of recent exposure to Francisella tularensis. A white-tailed deer (Odocoileus virginianus) had antibodies to Anaplasma marginale. All specimens tested for antibodies against Yersinia pestis and Brucella abortus were negative. Sera from 315 birds were tested for antibody against five equine encephalitis viruses and six avian pathogens. During 1988, antibodies to Venezuelan equine encephalitis-Mena II, Venezuelan equine encephalitis-TC83, St. Louis encephalitis, eastern equine encephalitis, and western equine encephalitis were detected in birds of several species. Antibodies to Pasteurella multocida and Newcastle disease virus were also detected. Birds from five species presented antibodies to Mycoplasma meleagridis. Specimens tested for M. gallisepticum, M. synoviae, and Chlamydia psittaci were negative. To the best of our knowledge, this survey represents the first serologic evidence of bluetongue, Cache Valley virus, epizootic hemorrhagic disease, Jamestown Canyon virus, vesicular stomatitis-Indiana, vesicular stomatitis-New Jersey, Rio Grande virus, and tularemia reported among wildlife in Mexico.

Development and evaluation of a novel high-throughput image-based fluorescent neutralization test for detection of Zika virus infection.

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Koishi, Andrea Cristine; Suzukawa, Andréia Akemi; Zanluca, Camila; Camacho, Daria Elena; Comach, Guillermo; Duarte Dos Santos, Claudia Nunes

2018-03-01

Zika virus (ZIKV) is an emerging arbovirus belonging to the genus flavivirus that comprises other important public health viruses, such as dengue (DENV) and yellow fever (YFV). In general, ZIKV infection is a self-limiting disease, however cases of Guillain-Barré syndrome and congenital brain abnormalities in newborn infants have been reported. Diagnosing ZIKV infection remains a challenge, as viral RNA detection is only applicable until a few days after the onset of symptoms. After that, serological tests must be applied, and, as expected, high cross-reactivity between ZIKV and other flavivirus serology is observed. Plaque reduction neutralization test (PRNT) is indicated to confirm positive samples for being more specific, however it is laborious intensive and time consuming, representing a major bottleneck for patient diagnosis. To overcome this limitation, we developed a high-throughput image-based fluorescent neutralization test for ZIKV infection by serological detection. Using 226 human specimens, we showed that the new test presented higher throughput than traditional PRNT, maintaining the correlation between results. Furthermore, when tested with dengue virus samples, it showed 50.53% less cross reactivity than MAC-ELISA. This fluorescent neutralization test could be used for clinical diagnosis confirmation of ZIKV infection, as well as for vaccine clinical trials and seroprevalence studies.

Zika virus disease

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Adel I Al-Afaleq

2017-01-01

Full Text Available The Zika virus is an arbovirus belonging to the virus family Flaviviridae. The virus was isolated in 1947 from a rhesus monkey in the Zika Forest of Uganda. The virus causes sporadic mild human infections in Africa and later in Asia. However, by 2007 a major shift in its infection pattern was noticed and thousands of human infections were reported in the State of Yap and Federated States of Micronesia. In the last 3 years, major outbreaks have continued to occur and the virus has spread to several Pacific and American countries. These outbreaks were mostly asymptomatic; however, there were more severe clinical signs associated with the infections. Those signs included microcephaly and Guillain–Barre syndrome. It is believed that various species of mosquitoes can biologically transmit the virus. However, Aedes aegypti is most widely associated with the Zika virus. Recently, new modes of virus transmission have been reported, including mother-to-fetus, sexual, blood transfusion, animal bites, laboratory exposure and breast milk. Differential diagnosis is very important as some other arboviruses such as yellow fever virus, West Nile virus, dengue virus, and chikungunya virus have similar clinical manifestations to the Zika virus infection as well as relating serologically to some of these viruses. Established laboratory diagnostic tests to detect the Zika virus are limited, with reverse transcription polymerase chain reaction being the most widely used test. Taking into consideration the quickness of the spread of infection, size of the infected population and change of the infection severity pattern, the Zika virus infection merits collective efforts on all levels to prevent and control the disease. Limited research work and data, concurrent infection with other arboviruses, involvement of biological vectors, mass crowd events, human and trade movements and lack of vaccines are some of the challenges that we face in our efforts to prevent and

Meta-Analysis of Aedes aegypti Expression Datasets: Comparing Virus Infection and Blood-Fed Transcriptomes to Identify Markers of Virus Presence

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Kiyoshi Ferreira Fukutani

2018-01-01

Full Text Available The mosquito Aedes aegypti (L. is vector of several arboviruses including dengue, yellow fever, chikungunya, and more recently zika. Previous transcriptomic studies have been performed to elucidate altered pathways in response to viral infection. However, the intrinsic coupling between alimentation and infection were unappreciated in these studies. Feeding is required for the initial mosquito contact with the virus and these events are highly dependent. Addressing this relationship, we reinterrogated datasets of virus-infected mosquitoes with two different diet schemes (fed and unfed mosquitoes, evaluating the metabolic cross-talk during both processes. We constructed coexpression networks with the differentially expressed genes of these comparison: virus-infected versus blood-fed mosquitoes and virus-infected versus unfed mosquitoes. Our analysis identified one module with 110 genes that correlated with infection status (representing ~0.7% of the A. aegypti genome. Furthermore, we performed a machine-learning approach and summarized the infection status using only four genes (AAEL012128, AAEL014210, AAEL002477, and AAEL005350. While three of the four genes were annotated as hypothetical proteins, AAEL012128 gene is a membrane amino acid transporter correlated with viral envelope binding. This gene alone is able to discriminate all infected samples and thus should have a key role to discriminate viral infection in the A. aegypti mosquito. Moreover, validation using external datasets found this gene as differentially expressed in four transcriptomic experiments. Therefore, these genes may serve as a proxy of viral infection in the mosquito and the others 106 identified genes provides a framework to future studies.

Mosquito-borne viral infections in southern Africa: a public health ...

African Journals Online (AJOL)

The agent in communicable disease is the organism, e.g. the yellow fever virus. Arbovirus ... the intervention strategies available for dealing with an outbreak of the disease. ... Control of a communicable disease can be directed at the agent,.

The Discovery of Arthropod-Specific Viruses in Hematophagous Arthropods: An Open Door to Understanding the Mechanisms of Arbovirus and Arthropod Evolution?

Science.gov (United States)

Calisher, Charles H; Higgs, Stephen

2018-01-07

The discovery of an odd virus from hematophagous arthropods 40 years ago by Stollar and Thomas described cell fusing agent virus in cells derived from Aedes aegypti mosquitoes. Then came the report of Kamiti River virus from Ae. macintoshi in 1999, followed by worldwide reports of the discovery of other viruses of mosquitoes, ticks, and midges that replicate only in arthropods and not in vertebrates or in vertebrate cells. These viruses (now totaling at least 64 published) have genomes analogous to viruses in various families that include arboviruses and nonarboviruses. It is likely that some of these viruses have been insufficiently studied and may yet be shown to infect vertebrates. However, there is no doubt that the vast majority are restricted to arthropods alone and that they represent a recently recognized clade. Their biology, modes of transmission, worldwide distribution (some have been detected in wild-caught mosquitoes in both Asia and the United States, for example), molecular characteristics of their genomes, and potential for becoming vertebrate pathogens, or at least serving as virus reservoirs, are fascinating and may provide evidence useful in understanding virus evolution. Because metagenomics studies of arthropods have shown that arthropod genomes are the sources of arthropod virus genomes, further studies may also provide insights into the evolution of arthropods. More recently, others have published excellent papers that briefly review discoveries of arthropod viruses and that characterize certain genomic peculiarities, but, to now, there have been no reviews that encompass all these facets. We therefore anticipate that this review is published at a time and in a manner that is helpful for both virologists and entomologists to make more sense and understanding of this recently recognized and obviously important virus group. This review focuses specifically on arthropod viruses in hematophagous arthropods.

Rainfall and Development of Zika Virus

African Journals Online (AJOL)

2017-11-01

Nov 1, 2017 ... between rainfall and incidence of arbovirus disease such as dengue is well demonstrated (2). For Zika virus an infection, a similar observation can be expected. A recent report from Thailand can also show the expected pattern of the prevalence of Zika virus infection in the areas with high rainfall (3).

Relationships between host viremia and vector susceptibility for arboviruses.

Science.gov (United States)

Lord, Cynthia C; Rutledge, C Roxanne; Tabachnick, Walter J

2006-05-01

Using a threshold model where a minimum level of host viremia is necessary to infect vectors affects our assessment of the relative importance of different host species in the transmission and spread of these pathogens. Other models may be more accurate descriptions of the relationship between host viremia and vector infection. Under the threshold model, the intensity and duration of the viremia above the threshold level is critical in determining the potential numbers of infected mosquitoes. A probabilistic model relating host viremia to the probability distribution of virions in the mosquito bloodmeal shows that the threshold model will underestimate the significance of hosts with low viremias. A probabilistic model that includes avian mortality shows that the maximum number of mosquitoes is infected by feeding on hosts whose viremia peaks just below the lethal level. The relationship between host viremia and vector infection is complex, and there is little experimental information to determine the most accurate model for different arthropod-vector-host systems. Until there is more information, the ability to distinguish the relative importance of different hosts in infecting vectors will remain problematic. Relying on assumptions with little support may result in erroneous conclusions about the importance of different hosts.

Type I interferons induced by endogenous or exogenous viral infections promote metastasis and relapse of leishmaniasis.

Science.gov (United States)

Rossi, Matteo; Castiglioni, Patrik; Hartley, Mary-Anne; Eren, Remzi Onur; Prével, Florence; Desponds, Chantal; Utzschneider, Daniel T; Zehn, Dietmar; Cusi, Maria G; Kuhlmann, F Matthew; Beverley, Stephen M; Ronet, Catherine; Fasel, Nicolas

2017-05-09

The presence of the endogenous Leishmania RNA virus 1 (LRV1) replicating stably within some parasite species has been associated with the development of more severe forms of leishmaniasis and relapses after drug treatment in humans. Here, we show that the disease-exacerbatory role of LRV1 relies on type I IFN (type I IFNs) production by macrophages and signaling in vivo. Moreover, infecting mice with the LRV1-cured Leishmania guyanensis ( LgyLRV1 - ) strain of parasites followed by type I IFN treatment increased lesion size and parasite burden, quantitatively reproducing the LRV1-bearing ( LgyLRV1 + ) infection phenotype. This finding suggested the possibility that exogenous viral infections could likewise increase pathogenicity, which was tested by coinfecting mice with L. guyanensis and lymphocytic choriomeningitis virus (LCMV), or the sand fly-transmitted arbovirus Toscana virus (TOSV). The type I IFN antiviral response increased the pathology of L. guyanensis infection, accompanied by down-regulation of the IFN-γ receptor normally required for antileishmanial control. Further, LCMV coinfection of IFN-γ-deficient mice promoted parasite dissemination to secondary sites, reproducing the LgyLRV1 + metastatic phenotype. Remarkably, LCMV coinfection of mice that had healed from L. guyanensis infection induced reactivation of disease pathology, overriding the protective adaptive immune response. Our findings establish that type I IFN-dependent responses, arising from endogenous viral elements (dsRNA/LRV1), or exogenous coinfection with IFN-inducing viruses, are able to synergize with New World Leishmania parasites in both primary and relapse infections. Thus, viral infections likely represent a significant risk factor along with parasite and host factors, thereby contributing to the pathological spectrum of human leishmaniasis.

Catalase protects Aedes aegypti from oxidative stress and increases midgut infection prevalence of Dengue but not Zika.

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Oliveira, José Henrique M; Talyuli, Octávio A C; Goncalves, Renata L S; Paiva-Silva, Gabriela Oliveira; Sorgine, Marcos Henrique F; Alvarenga, Patricia Hessab; Oliveira, Pedro L

2017-04-01

Digestion of blood in the midgut of Aedes aegypti results in the release of pro-oxidant molecules that can be toxic to the mosquito. We hypothesized that after a blood meal, the antioxidant capacity of the midgut is increased to protect cells against oxidative stress. Concomitantly, pathogens present in the blood ingested by mosquitoes, such as the arboviruses Dengue and Zika, also have to overcome the same oxidative challenge, and the antioxidant program induced by the insect is likely to influence infection status of the mosquito and its vectorial competence. We found that blood-induced catalase mRNA and activity in the midgut peaked 24 h after feeding and returned to basal levels after the completion of digestion. RNAi-mediated silencing of catalase (AAEL013407-RB) reduced enzyme activity in the midgut epithelia, increased H2O2 leakage and decreased fecundity and lifespan when mosquitoes were fed H2O2. When infected with Dengue 4 and Zika virus, catalase-silenced mosquitoes showed no alteration in infection intensity (number of plaque forming units/midgut) 7 days after the infectious meal. However, catalase knockdown reduced Dengue 4, but not Zika, infection prevalence (percent of infected midguts). Here, we showed that blood ingestion triggers an antioxidant response in the midgut through the induction of catalase. This protection facilitates the establishment of Dengue virus in the midgut. Importantly, this mechanism appears to be specific for Dengue because catalase silencing did not change Zika virus prevalence. In summary, our data suggest that redox balance in the midgut modulates mosquito vectorial competence to arboviral infections.

Temporal distribution and insecticide resistance profile of two major arbovirus vectors Aedes aegypti and Aedes albopictus in Yaoundé, the capital city of Cameroon.

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Kamgang, Basile; Yougang, Aurelie P; Tchoupo, Micareme; Riveron, Jacob M; Wondji, Charles

2017-10-10

Aedes aegypti and Ae. albopictus are the major epidemic vectors of several arbovirus diseases such as yellow fever, dengue, Zika and chikungunya worldwide. Both Aedes vectors are presents in Cameroon; however, knowledge on the dynamic of the distribution of these species across cities and their resistance profile to insecticide are limited. Here, we assessed the current distribution of Ae. aegypti and Ae. albopictus in Yaoundé, the Capital City, established the resistance profile to insecticides and explored the resistance mechanisms involved. Immature stages of Aedes were sampled in several breeding sites in December 2015 (dry season) and June 2016 (rainy season) in three central neighborhoods and four peripheral neighborhoods and reared to adult stage. The G0 adults were used for molecular identification and genotyping of F1534C mutation in Ae. aegypti. Bioassays and piperonyl butoxide (PBO) assays were carried out according to WHO guidelines. Analysis revealed that both species Ae. aegypti and Ae. albopictus are present in all prospected sites in Yaounde. However, in the dry season Ae. aegypti is most abundant in neighborhoods located in downtown. In contrast, Ae. albopictus was found most prevalent in suburbs whatever the season and in downtown during the rainy season. Bioassay analysis showed that both Ae. aegypti and Ae. albopictus, are resistant to 0.05% deltamethrin, 0.1% bendiocarb and 4% dichlorodiphenyltrichloroethane (DDT). A decreased of susceptibility to 0.75% permethrin and a full susceptibility to malathion 5% was observed. The mortality rate was increased after pre-exposure to synergist PBO. None of Ae. aegypti assayed revealed the presence of F1534C mutation. These findings are useful to planning vector control programme against arbovirus vectors in Cameroon and can be used as baseline in Africa where data on Aedes resistance is very scarce to plan further works.

Mosquito-specific and mosquito-borne viruses: evolution, infection, and host defense

NARCIS (Netherlands)

Halbach, R.; Junglen, S.; Rij, R.P. van

2017-01-01

Recent virus discovery programs have identified an extensive reservoir of viruses in arthropods. It is thought that arthropod viruses, including mosquito-specific viruses, are ancestral to vertebrate-pathogenic arboviruses. Mosquito-specific viruses are restricted in vertebrate cells at multiple

Dengue virus type 2: replication and tropisms in orally infected Aedes aegypti mosquitoes.

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Salazar, Ma Isabel; Richardson, Jason H; Sánchez-Vargas, Irma; Olson, Ken E; Beaty, Barry J

2007-01-30

To be transmitted by its mosquito vector, dengue virus (DENV) must infect midgut epithelial cells, replicate and disseminate into the hemocoel, and finally infect the salivary glands, which is essential for transmission. The extrinsic incubation period (EIP) is very relevant epidemiologically and is the time required from the ingestion of virus until it can be transmitted to the next vertebrate host. The EIP is conditioned by the kinetics and tropisms of virus replication in its vector. Here we document the virogenesis of DENV-2 in newly-colonized Aedes aegypti mosquitoes from Chetumal, Mexico in order to understand better the effect of vector-virus interactions on dengue transmission. After ingestion of DENV-2, midgut infections in Chetumal mosquitoes were characterized by a peak in virus titers between 7 and 10 days post-infection (dpi). The amount of viral antigen and viral titers in the midgut then declined, but viral RNA levels remained stable. The presence of DENV-2 antigen in the trachea was positively correlated with virus dissemination from the midgut. DENV-2 antigen was found in salivary gland tissue in more than a third of mosquitoes at 4 dpi. Unlike in the midgut, the amount of viral antigen (as well as the percent of infected salivary glands) increased with time. DENV-2 antigen also accumulated and increased in neural tissue throughout the EIP. DENV-2 antigen was detected in multiple tissues of the vector, but unlike some other arboviruses, was not detected in muscle. Our results suggest that the EIP of DENV-2 in its vector may be shorter that the previously reported and that the tracheal system may facilitate DENV-2 dissemination from the midgut. Mosquito organs (e.g. midgut, neural tissue, and salivary glands) differed in their response to DENV-2 infection.

Dengue virus type 2: replication and tropisms in orally infected Aedes aegypti mosquitoes

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Olson Ken E

2007-01-01

Full Text Available Abstract Background To be transmitted by its mosquito vector, dengue virus (DENV must infect midgut epithelial cells, replicate and disseminate into the hemocoel, and finally infect the salivary glands, which is essential for transmission. The extrinsic incubation period (EIP is very relevant epidemiologically and is the time required from the ingestion of virus until it can be transmitted to the next vertebrate host. The EIP is conditioned by the kinetics and tropisms of virus replication in its vector. Here we document the virogenesis of DENV-2 in newly-colonized Aedes aegypti mosquitoes from Chetumal, Mexico in order to understand better the effect of vector-virus interactions on dengue transmission. Results After ingestion of DENV-2, midgut infections in Chetumal mosquitoes were characterized by a peak in virus titers between 7 and 10 days post-infection (dpi. The amount of viral antigen and viral titers in the midgut then declined, but viral RNA levels remained stable. The presence of DENV-2 antigen in the trachea was positively correlated with virus dissemination from the midgut. DENV-2 antigen was found in salivary gland tissue in more than a third of mosquitoes at 4 dpi. Unlike in the midgut, the amount of viral antigen (as well as the percent of infected salivary glands increased with time. DENV-2 antigen also accumulated and increased in neural tissue throughout the EIP. DENV-2 antigen was detected in multiple tissues of the vector, but unlike some other arboviruses, was not detected in muscle. Conclusion Our results suggest that the EIP of DENV-2 in its vector may be shorter that the previously reported and that the tracheal system may facilitate DENV-2 dissemination from the midgut. Mosquito organs (e.g. midgut, neural tissue, and salivary glands differed in their response to DENV-2 infection.

Application of modified shell vial culture procedure for arbovirus detection.

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Edna R Caceda

Full Text Available The isolation of arboviruses from patient's low titer sera can be difficult. Here we compared the detection efficiency of Dengue (DEN, Yellow Fever (YF, Saint Louis Encephalitis (SLE, West Nile (WN, Ilheus (ILH, Group C (GC, Oropouche (ORO, Mayaro (MAY and Venezuela Encephalitis Equine (VEE viruses using a Modified Shell Vial Culture (MSVC protocol to a Standard Cell Culture (SCC protocol. First the MSVC and SCC protocols were compared using five dilutions for each of the following stock viruses: DEN-1, DEN-2, DEN-3, DEN-4, YF, SLE, WN, ILH, GC, ORO, MAY and VEE. Next, patients' original sera from which viruses (DEN-1, DEN-2, DEN-3, YF, GC, ORO, MAY and VEE had been previously isolated were compare by the two methods using five sera dilutions. In addition, seven sera that were positive for DEN-3 by RT-PCR and negative by SCC were processed by MSVC. The MSVC protocol was consistently 1-2 logs higher virus dilution more sensitive for virus detection than the SCC protocol for all stock Flaviviruses tested (DEN-1, DEN-2, DEN-3, DEN-4, YF, SLE, WN and ILH. MSVC was equal to or one log more sensitive for virus detection than SCC for the stock Bunyaviruses (GC and ORO. For the stock Alphavirus MAY, MSVC was equally or one log more sensitive for virus detection than SCC, while for VEE SCC was equally or one log more sensitive for virus detection than MSVC. MSVC was consistently one to two sera dilutions more sensitive than SCC for the detection of Flaviviruses from patients' sera. Both methods were approximately equally sensitive for the detection of Bunyaviruses from patients' sera and equal or one dilution less sensitive for the detection of Alphaviruses from patients' sera. Additionally, MSVC detected DEN virus in five of seven DEN-3 RT-PCR positive, SCC negative patients' sera.

Neutralizing antibodies against flaviviruses, Babanki virus, and Rift Valley fever virus in Ugandan bats.

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Kading, Rebekah C; Kityo, Robert M; Mossel, Eric C; Borland, Erin M; Nakayiki, Teddie; Nalikka, Betty; Nyakarahuka, Luke; Ledermann, Jeremy P; Panella, Nicholas A; Gilbert, Amy T; Crabtree, Mary B; Peterhans, Julian Kerbis; Towner, Jonathan S; Amman, Brian R; Sealy, Tara K; Nichol, Stuart T; Powers, Ann M; Lutwama, Julius J; Miller, Barry R

2018-01-01

Introduction: A number of arboviruses have previously been isolated from naturally-infected East African bats, however the role of bats in arbovirus maintenance is poorly understood. The aim of this study was to investigate the exposure history of Ugandan bats to a panel of arboviruses. Materials and methods: Insectivorous and fruit bats were captured from multiple locations throughout Uganda during 2009 and 2011-2013. All serum samples were tested for neutralizing antibodies against West Nile virus (WNV), yellow fever virus (YFV), dengue 2 virus (DENV-2), Zika virus (ZIKV), Babanki virus (BBKV), and Rift Valley fever virus (RVFV) by plaque reduction neutralization test (PRNT). Sera from up to 626 bats were screened for antibodies against each virus. Results and Discussion:  Key findings include the presence of neutralizing antibodies against RVFV in 5/52 (9.6%) of little epauletted fruit bats ( Epomophorus labiatus ) captured from Kawuku and 3/54 (5.6%) Egyptian rousette bats from Kasokero cave. Antibodies reactive to flaviviruses were widespread across bat taxa and sampling locations. Conclusion: The data presented demonstrate the widespread exposure of bats in Uganda to arboviruses, and highlight particular virus-bat associations that warrant further investigation.

Four emerging arboviral diseases in North America: Jamestown Canyon, Powassan, chikungunya, and Zika virus diseases.

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Pastula, Daniel M; Smith, Daniel E; Beckham, J David; Tyler, Kenneth L

2016-06-01

Arthropod-borne viruses, or arboviruses, are viruses that are transmitted through the bites of mosquitoes, ticks, or sandflies. There are numerous arboviruses throughout the world capable of causing human disease spanning different viral families and genera. Recently, Jamestown Canyon, Powassan, chikungunya, and Zika viruses have emerged as increasingly important arboviruses that can cause human disease in North America. Unfortunately, there are currently no proven disease-modifying therapies for these arboviral diseases, so treatment is largely supportive. Given there are also no commercially available vaccines for these four arboviral infections, prevention is the key. To prevent mosquito or tick bites that might result in one of these arboviral diseases, people should wear long-sleeved shirts and pants while outside if feasible, apply insect repellant when going outdoors, using window screens or air conditioning to keep mosquitoes outside, and perform tick checks after being in wooded or brushy outdoor areas.

Survey of UK horse owners' knowledge of equine arboviruses and disease vectors.

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Chapman, Gail Elaine; Baylis, Matthew; Archer, Debra C

2018-05-15

Increased globalisation and climate change have led to concern about the increasing risk of arthropod-borne virus (arbovirus) outbreaks globally. An outbreak of equine arboviral disease in northern Europe could impact significantly on equine welfare, and result in economic losses. Early identification of arboviral disease by horse owners may help limit disease spread. In order to determine what horse owners understand about arboviral diseases of horses and their vectors, the authors undertook an open, cross-sectional online survey of UK horse owners. The questionnaire was distributed using social media and a press release and was active between May and July 2016. There were 466 respondents, of whom 327 completed the survey in full. High proportions of respondents correctly identified photographic images of biting midges (71.2 per cent) and mosquitoes (65.4 per cent), yet few were aware that they transmit equine infectious diseases (31.4 per cent and 35.9 per cent, respectively). Of the total number of respondents, only 7.4 per cent and 16.2 per cent correctly named a disease transmitted by biting midges and mosquitoes, respectively. Only 13.1 per cent and 12.5 per cent of participants identified specific clinical signs of African horse sickness (AHS) and West Nile virus (WNV), respectively. This study demonstrates that in the event of heightened disease risk educational campaigns directed towards horse owners need to be implemented, focussing on disease awareness, clinical signs and effective disease prevention strategies. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Culicoides-virus interactions: infection barriers and possible factors underlying vector competence

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In the United States, Culicoides midges vector arboviruses of economic importance such as Bluetongue Virus and Epizootic Hemorrhagic Disease Virus. A limited number of studies have demonstrated the complexities of midge-virus interactions, including dynamic changes in virus titer and prevalence over...

Anopheles gambiae antiviral immune response to systemic O'nyong-nyong infection.

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Joanna Waldock

Full Text Available Mosquito-borne viral diseases cause significant burden in much of the developing world. Although host-virus interactions have been studied extensively in the vertebrate host, little is known about mosquito responses to viral infection. In contrast to mosquitoes of the Aedes and Culex genera, Anopheles gambiae, the principal vector of human malaria, naturally transmits very few arboviruses, the most important of which is O'nyong-nyong virus (ONNV. Here we have investigated the A. gambiae immune response to systemic ONNV infection using forward and reverse genetic approaches.We have used DNA microarrays to profile the transcriptional response of A. gambiae inoculated with ONNV and investigate the antiviral function of candidate genes through RNAi gene silencing assays. Our results demonstrate that A. gambiae responses to systemic viral infection involve genes covering all aspects of innate immunity including pathogen recognition, modulation of immune signalling, complement-mediated lysis/opsonisation and other immune effector mechanisms. Patterns of transcriptional regulation and co-infections of A. gambiae with ONNV and the rodent malaria parasite Plasmodium berghei suggest that hemolymph immune responses to viral infection are diverted away from melanisation. We show that four viral responsive genes encoding two putative recognition receptors, a galectin and an MD2-like receptor, and two effector lysozymes, function in limiting viral load.This study is the first step in elucidating the antiviral mechanisms of A. gambiae mosquitoes, and has revealed interesting differences between A. gambiae and other invertebrates. Our data suggest that mechanisms employed by A. gambiae are distinct from described invertebrate antiviral immunity to date, and involve the complement-like branch of the humoral immune response, supressing the melanisation response that is prominent in anti-parasitic immunity. The antiviral immune response in A. gambiae is thus

Zika virus: history of a newly emerging arbovirus.

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Wikan, Nitwara; Smith, Duncan R

2016-07-01

Zika virus was originally identified in a sentinel rhesus monkey in the Zika Forest of Uganda in 1947. The virus is a member of the family Flaviviridae, genus Flavivirus, and is transmitted to humans by Aedes species mosquitoes. The first report of Zika virus outside Africa and Asia was in 2007 when the virus was associated with a small outbreak in Yap State, part of the Federated States of Micronesia. Since then, Zika virus infections have been reported around the world, including in southeast Asia; French Polynesia and other islands in the Pacific Ocean; and parts of South, Central, and North America. Symptomatic infection in human beings normally results in a mild and self-limiting febrile disease, although recent reports have suggested a possible association with more serious sequelae such as Guillain-Barré syndrome, and microcephaly in newborn infants of mothers infected with Zika virus during pregnancy. In this Review, we summarise the history of Zika virus from its first detection to its current worldwide distribution. Copyright © 2016 Elsevier Ltd. All rights reserved.

The global burden of dengue: an analysis from the Global Burden of Disease Study 2013

NARCIS (Netherlands)

J.D. Stanaway (Jeffrey D.); D.S. Shepard (Donald); E.A. Undurraga (Eduardo); Halasa, Y.A. (Yara A); L.E. Coffeng (Luc); Brady, O.J. (Oliver J); Hay, S.I. (Simon I); Bedi, N. (Neeraj); I.M. Bensenor (Isabela M.); C.A. Castañeda-Orjuela (Carlos A); T.-W. Chuang (Ting-Wu); K.B. Gibney (Katherine B); Z.A. Memish (Ziad); A. Rafay (Anwar); K.N. Ukwaja (Kingsley N); N. Yonemoto (Naohiro); C.J.L. Murray (Christopher)

2016-01-01

textabstractBackground Dengue is the most common arbovirus infection globally, but its burden is poorly quantified. We estimated dengue mortality, incidence, and burden for the Global Burden of Disease Study 2013. Methods We modelled mortality from vital registration, verbal autopsy, and

Catalase protects Aedes aegypti from oxidative stress and increases midgut infection prevalence of Dengue but not Zika.

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José Henrique M Oliveira

2017-04-01

Full Text Available Digestion of blood in the midgut of Aedes aegypti results in the release of pro-oxidant molecules that can be toxic to the mosquito. We hypothesized that after a blood meal, the antioxidant capacity of the midgut is increased to protect cells against oxidative stress. Concomitantly, pathogens present in the blood ingested by mosquitoes, such as the arboviruses Dengue and Zika, also have to overcome the same oxidative challenge, and the antioxidant program induced by the insect is likely to influence infection status of the mosquito and its vectorial competence.We found that blood-induced catalase mRNA and activity in the midgut peaked 24 h after feeding and returned to basal levels after the completion of digestion. RNAi-mediated silencing of catalase (AAEL013407-RB reduced enzyme activity in the midgut epithelia, increased H2O2 leakage and decreased fecundity and lifespan when mosquitoes were fed H2O2. When infected with Dengue 4 and Zika virus, catalase-silenced mosquitoes showed no alteration in infection intensity (number of plaque forming units/midgut 7 days after the infectious meal. However, catalase knockdown reduced Dengue 4, but not Zika, infection prevalence (percent of infected midguts.Here, we showed that blood ingestion triggers an antioxidant response in the midgut through the induction of catalase. This protection facilitates the establishment of Dengue virus in the midgut. Importantly, this mechanism appears to be specific for Dengue because catalase silencing did not change Zika virus prevalence. In summary, our data suggest that redox balance in the midgut modulates mosquito vectorial competence to arboviral infections.

Zika, chikungunya and dengue: the causes and threats of new and re-emerging arboviral diseases.

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Paixão, Enny S; Teixeira, Maria Gloria; Rodrigues, Laura C

2018-01-01

The recent emergence and re-emergence of viral infections transmitted by vectors-Zika, chikungunya, dengue, Japanese encephalitis, West Nile, yellow fever and others-is a cause for international concern. Using as examples Zika, chikungunya and dengue, we summarise current knowledge on characteristics of the viruses and their transmission, clinical features, laboratory diagnosis, burden, history, possible causes of the spread and the expectation for future epidemics. Arboviruses are transmitted by mosquitoes, are of difficult diagnosis, can have surprising clinical complications and cause severe burden. The current situation is complex, because there is no vaccine for Zika and chikungunya and no specific treatment for the three arboviruses. Vector control is the only comprehensive solution available now and this remains a challenge because up to now this has not been very effective. Until we develop new technologies of control mosquito populations, the globalised and urbanised world we live in will remain vulnerable to the threat of successive arbovirus epidemics.

Knowledge, Attitude and Practices of Vector-Borne Disease Prevention during the Emergence of a New Arbovirus: Implications for the Control of Chikungunya Virus in French Guiana.

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Camille Fritzell

2016-11-01

Full Text Available During the last decade, French Guiana has been affected by major dengue fever outbreaks. Although this arbovirus has been a focus of many awareness campaigns, very little information is available about beliefs, attitudes and behaviors regarding vector-borne diseases among the population of French Guiana. During the first outbreak of the chikungunya virus, a quantitative survey was conducted among high school students to study experiences, practices and perceptions related to mosquito-borne diseases and to identify socio-demographic, cognitive and environmental factors that could be associated with the engagement in protective behaviors.A cross-sectional survey was administered in May 2014, with a total of 1462 students interviewed. Classrooms were randomly selected using a two-stage selection procedure with cluster samples. A multiple correspondence analysis (MCA associated with a hierarchical cluster analysis and with an ordinal logistic regression was performed. Chikungunya was less understood and perceived as a more dreadful disease than dengue fever. The analysis identified three groups of individual protection levels against mosquito-borne diseases: "low" (30%, "moderate" (42% and "high" (28%". Protective health behaviors were found to be performed more frequently among students who were female, had a parent with a higher educational status, lived in an individual house, and had a better understanding of the disease.This study allowed us to estimate the level of protective practices against vector-borne diseases among students after the emergence of a new arbovirus. These results revealed that the adoption of protective behaviors is a multi-factorial process that depends on both sociocultural and cognitive factors. These findings may help public health authorities to strengthen communication and outreach strategies, thereby increasing the adoption of protective health behaviors, particularly in high-risk populations.

Host-pathogen interactions and genome evolution in two generalist and specialist microsporidian pathogens of mosquitoes

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The adaptation of two distantly related microsporidia to their mosquito hosts was investigated. Edhazardia aedis is a specialist pathogen that infects Aedes aegypti, the main vector of dengue and yellow fever arboviruses. Vavraia culicis is a generalist pathogen of several insects including Anophele...

West nile virus prevalence across landscapes is mediated by local effects of agriculture on vector and host communities.

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Crowder, David W; Dykstra, Elizabeth A; Brauner, Jo Marie; Duffy, Anne; Reed, Caitlin; Martin, Emily; Peterson, Wade; Carrière, Yves; Dutilleul, Pierre; Owen, Jeb P

2013-01-01

Arthropod-borne viruses (arboviruses) threaten the health of humans, livestock, and wildlife. West Nile virus (WNV), the world's most widespread arbovirus, invaded the United States in 1999 and rapidly spread across the county. Although the ecology of vectors and hosts are key determinants of WNV prevalence across landscapes, the factors shaping local vector and host populations remain unclear. Here, we used spatially-explicit models to evaluate how three land-use types (orchards, vegetable/forage crops, natural) and two climatic variables (temperature, precipitation) influence the prevalence of WNV infections and vector/host distributions at landscape and local spatial scales. Across landscapes, we show that orchard habitats were associated with greater prevalence of WNV infections in reservoirs (birds) and incidental hosts (horses), while increased precipitation was associated with fewer infections. At local scales, orchard habitats increased the prevalence of WNV infections in vectors (mosquitoes) and the abundance of mosquitoes and two key reservoir species, the American robin and the house sparrow. Thus, orchard habitats benefitted WNV vectors and reservoir hosts locally, creating focal points for the transmission of WNV at landscape scales in the presence of suitable climatic conditions.

The spectrum of neurological disease associated with Zika and chikungunya viruses in adults in Rio de Janeiro, Brazil: A case series

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da Silva, Marcus Tulius Texeira; Rosala-Hallas, Anna; Jardim, Marcia Rodrigues; Burnside, Girvan; Pamplona, Luciana; Bhojak, Maneesh; Manohar, Radhika; da Silva, Gabriel Amorelli Medeiros; Adriano, Marcus Vinicius; Brasil, Patricia; Nogueira, Rita Maria Ribeiro; Dos Santos, Carolina Cardoso; Turtle, Lance; de Sequeira, Patricia Carvalho; Brown, David W.; Griffiths, Michael J.; de Filippis, Ana Maria Bispo

2018-01-01

Background During 2015–16 Brazil experienced the largest epidemic of Zika virus ever reported. This arthropod-borne virus (arbovirus) has been linked to Guillain-Barré syndrome (GBS) in adults but other neurological associations are uncertain. Chikungunya virus has caused outbreaks in Brazil since 2014 but associated neurological disease has rarely been reported here. We investigated adults with acute neurological disorders for Zika, chikungunya and dengue, another arbovirus circulating in Brazil. Methods We studied adults who had developed a new neurological condition following suspected Zika virus infection between 1st November 2015 and 1st June 2016. Cerebrospinal fluid (CSF), serum, and urine were tested for evidence of Zika, chikungunya, and dengue viruses. Results Of 35 patients studied, 22 had evidence of recent arboviral infection. Twelve had positive PCR or IgM for Zika, five of whom also had evidence for chikungunya, three for dengue, and one for all three viruses. Five of them presented with GBS; seven had presentations other than GBS, including meningoencephalitis, myelitis, radiculitis or combinations of these syndromes. Additionally, ten patients positive for chikungunya virus, two of whom also had evidence for dengue virus, presented with a similar range of neurological conditions. Conclusions Zika virus is associated with a wide range of neurological manifestations, including central nervous system disease. Chikungunya virus appears to have an equally important association with neurological disease in Brazil, and many patients had dual infection. To understand fully the burden of Zika we must look beyond GBS, and also investigate for other co-circulating arboviruses, particularly chikungunya. PMID:29432457

Dengue Fever/Dengue Haemorrhagic Fever : Case Management

OpenAIRE

Nimmannitya, Suchitra

1995-01-01

Dengue infections caused by the four antigenically distinct dengue virus serotypes (dengue virus 1, dengue virus 2, dengue virus 3, dengue virus 4) of the family Flavivindae, are the most important arbovirus disease in man, both in terms of morbidity and mortality. The infection is transmitted from man to man by Aedes mosquitoes. Since 1956, dengue virus infection has resulted in more than 3 million hospital admissions and more than 50,000 deaths in Southeast Asia, Western Pacific countries, ...

Serum metabolome and lipidome changes in adult patients with primary dengue infection.

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Liang Cui

Full Text Available Dengue virus (DENV is the most widespread arbovirus with an estimated 100 million infections occurring every year. Endemic in the tropical and subtropical areas of the world, dengue fever/dengue hemorrhagic fever (DF/DHF is emerging as a major public health concern. The complex array of concurrent host physiologic changes has hampered a complete understanding of underlying molecular mechanisms of dengue pathogenesis.Systems level characterization of serum metabolome and lipidome of adult DF patients at early febrile, defervescence, and convalescent stages of DENV infection was performed using liquid chromatography- and gas chromatography-mass spectrometry. The tractability of following metabolite and lipid changes in a relatively large sample size (n = 44 across three prominent infection stages allowed the identification of critical physiologic changes that coincided with the different stages. Sixty differential metabolites were identified in our metabolomics analysis and the main metabolite classes were free fatty acids, acylcarnitines, phospholipids, and amino acids. Major perturbed metabolic pathways included fatty acid biosynthesis and β-oxidation, phospholipid catabolism, steroid hormone pathway, etc., suggesting the multifactorial nature of human host responses. Analysis of phospholipids and sphingolipids verified the temporal trends and revealed association with lymphocytes and platelets numbers. These metabolites were significantly perturbed during the early stages, and normalized to control levels at convalescent stage, suggesting their potential utility as prognostic markers.DENV infection causes temporally distinct serum metabolome and lipidome changes, and many of the differential metabolites are involved in acute inflammatory responses. Our global analyses revealed early anti-inflammatory responses working in concert to modulate early pro-inflammatory processes, thus preventing the host from development of pathologies by excessive

Eco-friendly control of malaria and arbovirus vectors using the mosquitofish Gambusia affinis and ultra-low dosages of Mimusops elengi-synthesized silver nanoparticles: towards an integrative approach?

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Subramaniam, Jayapal; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Kovendan, Kalimuthu; Madhiyazhagan, Pari; Kumar, Palanisamy Mahesh; Dinesh, Devakumar; Chandramohan, Balamurugan; Suresh, Udaiyan; Nicoletti, Marcello; Higuchi, Akon; Hwang, Jiang-Shiou; Kumar, Suresh; Alarfaj, Abdullah A; Munusamy, Murugan A; Messing, Russell H; Benelli, Giovanni

2015-12-01

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to high operational costs and adverse non-target effects. Plant-borne compounds have been proposed for rapid extracellular synthesis of mosquitocidal nanoparticles. Their impact against biological control agents of mosquito larval populations has been poorly studied. We synthesized silver nanoparticles (AgNP) using the aqueous leaf extract of Mimusops elengi as a reducing and stabilizing agent. The formation of AgNP was studied using different biophysical methods, including UV-vis spectrophotometry, TEM, XRD, EDX and FTIR. Low doses of AgNP showed larvicidal and pupicidal toxicity against the malaria vector Anopheles stephensi and the arbovirus vector Aedes albopictus. AgNP LC50 against A. stephensi ranged from 12.53 (I instar larvae) to 23.55 ppm (pupae); LC50 against A. albopictus ranged from 11.72 ppm (I) to 21.46 ppm (pupae). In the field, the application of M. elengi extract and AgNP (10 × LC50) led to 100 % larval reduction after 72 h. In adulticidal experiments, AgNP showed LC50 of 13.7 ppm for A. stephensi and 14.7 ppm for A. albopictus. The predation efficiency of Gambusia affinis against A. stephensi and A. albopictus III instar larvae was 86.2 and 81.7 %, respectively. In AgNP-contaminated environments, predation was 93.7 and 88.6 %, respectively. This research demonstrates that M. elengi-synthesized AgNP may be employed at ultra-low doses to reduce larval populations of malaria and arbovirus vectors, without detrimental effects on predation rates of mosquito natural enemies, such as larvivorous fishes.

Environment, arbovirus transmission and control of epidemics Ambiente, transmissão de arbovírus e controle de epidemias

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Roger Cordellier

1992-09-01

Full Text Available In order to illustrate the relationships between the biotopes (or phytogeographical zones, arbovirus vectors and vertebrate hosts (including man, and epidemiology, current knowledge on the transmission of Yellow Fever virus in West Africa is reported. A dynamic scheme has been devised to integrate the observed geographical distribution of cases and the timing of their occurrence. Two principal areas, endemicity and epidetnicity, were defined according to the presence or absence of sylvatic monkey-mosquito transmission. The intensity and potential of contacts between humans and vectors depends on the degree of man-made changes in the environment, often increasing the extension of ecotone areas where the mosquitoes are easily biting at the ground level. Prevention and/or control of arbovirus diseases require detailed eco-epidemiological studies to determine: (1 the effective role of each potential vector in each phytogeographical region; (2 the risk factors for the people living in or near areas with a sylvatic transmission cycle; (3 the priorities - vaccination and/or control - for preventing the expansion of natural foci.Para ilustrar as relações existentes entre os biótopos (ou zonas fitogeográficas, os vetores e hospedeiros vertebrados (incluindo o homem de arbovírus e a epidemiologia, o conhecimento atual sobre a transmissão do vírus de febre amarela na África Ocidental é apresentado e discutido. Um modelo dinâmico foi desenvolvido para integrar a distribuição geográfica dos casos observados e o momento de sua ocorrência. Duas áreas principais, endemicidade e epidemicidade, foram definidas de acordo com a presença ou ausência de transmissão silvática macaco-mosquito. A intensidade e o potencial dos contatos entre homem e vetores depende do grau das alterações ambientais produzidas pelas atividades humanas, geralmente aumentando a extensão das áreas de ecótono onde os mosquitos estão ativos ao nível do solo. A preven

Níveis de anticorpos para arbovírus em indivíduos da região de Ribeirão Preto, SP (Brasil Arbovirus antibody levels in the population of the Ribeirão Preto area, S.Paulo State (Brazil

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Luiz Tadeu Moraes Figueiredo

1986-06-01

against arbovirus. The Flavivirus Togaviridae antibodies were the most frequent among inhabitants from urban communities (8.5%. Anti amarilic vaccination, carried out 8 years ago, explains this fact. Piry Rhabdoviridae obtained 12.5%, the most significant population in proportion of antibodies detected. Thirty two percent of inhabitants in a place close to natural landscape, 11.5% of inhabitants in places with landscape modified by agriculture and cattle raising, and 7,5% of inhabitants in urban communities presented Piry antibodies. This virus has never before been discovered in the south of Brazil. The highest risk of infection by Piry virus was found in men, especially older than forty: agricultural workers, forestry wardens and river workers. These conclusions are typical of a virus related to a natural environment. Geographical space is changeable, and organized according to the characteristics of a civilization at a particular point in time. The geographical space approach is more advantageous than a purely ecological view on zoonoses research in populated and organized areas in the south of Brazil.

Effect of environmental temperature on the vector competence of mosquitoes for Rift Valley fever virus

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Environmental temperature has been shown to affect the ability of mosquitoes to transmit numerous arboviruses and for Rift Valley fever virus (RVFV) in particular. We evaluated the effect of incubation temperatures ranging from 14-26ºC on infection, dissemination, and transmission rates for Culex ta...

Beware: It’s Mosquito Season (A Minute of Health with CDC)

Centers for Disease Control (CDC) Podcasts

2013-06-27

West Nile and other arboviruses viruses cause thousands of people to get sick each summer. This podcast discusses ways to reduce your chances of becoming infected, including use of insect repellant.  Created: 6/27/2013 by MMWR.   Date Released: 6/27/2013.

An overview of mosquitoes and emerging arboviral infections in the Zagreb area, Croatia.

Science.gov (United States)

Klobucar, Ana; Benic, Nikola; Krajcar, Darko; Kosanovic-Licina, Mirjana Lana; Tesic, Vanja; Merdic, Enrih; Vrucina, Ivana; Savic, Vladimir; Barbic, Ljubo; Stevanovic, Vladimir; Pem-Novosel, Iva; Vilibic-Cavlek, Tatjana

2016-12-30

Mosquito control in the Zagreb area has been conducted for many years, whereas the fauna has only been investigated in the last 20 years. So far 30 mosquito species have been detected in the city area. Culex pipiens form molestus is the dominant mosquito species in indoor breeding sites. In forested areas and areas exposed to flooding, the active period is early spring and the dominant species are Ochlerotatus sticticus, Ochlerotatus cantans, Ochlerotatus geniculatus and Aedes vexans. The eudominant mosquito species found in the artificial breeding sites are Culex pipiens and the Asian tiger mosquito, Aedes albopictus. Invasive Ae. albopictus, present in the Zagreb area since 2004, has expanded to a larger area of the city during the last three years. The recent emergence of the human West Nile virus and Usutu virus neuroinvasive disease in Zagreb and its surroundings highlighted the role of mosquitoes as vectors of emerging arboviruses. The paper focuses on mosquito species and arboviral infections detected in humans and animals in the Zagreb area, Croatia.

Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus) in four strains of Culex tarsalis (Diptera: Culicidae): an immunocytochemical study.

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Oviedo, Marco V Neira; Romoser, William S; James, Calvin Bl; Mahmood, Farida; Reisen, William K

2011-04-18

BACKGROUND: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV), we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion. METHODS: Using immunostained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains - Coachella Valley, Riverside County (COAV) and Kern National Wildlife Refuge (KNWR); and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP), and WEEV resistance (WR). RESULTS AND CONCLUSIONS: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth, whereas the WR and KNWR strains were less competent. Consistent with earlier studies, WEEV resistance appeared to be related to a dose-dependent midgut infection barrier, and a midgut escape barrier. The midgut escape barrier was not dependent upon the ingested viral dose. Consistent with midgut infection modulation, disseminated infections were less common in the WR and KNWR

Electron Tomography Analysis of Tick-Borne Encephalitis Virus Infection in Human Neurons

Czech Academy of Sciences Publication Activity Database

Bílý, Tomáš; Palus, Martin; Eyer, L.; Elsterová, Jana; Vancová, Marie; Růžek, Daniel

2015-01-01

Roč. 5, JUN 15 2015 (2015), s. 10745 ISSN 2045-2322 R&D Projects: GA ČR GAP502/11/2116; GA TA ČR(CZ) TE01020118 Institutional support: RVO:60077344 Keywords : dengue virus * replication sites * arboviruses Subject RIV: EE - Microbiology, Virology Impact factor: 5.228, year: 2015

Antibody Prevalence of Select Arboviruses in Mute Swans (Cygnus olor) in the Great Lakes Region and Atlantic Coast of the United States

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Pedersen, Kerri; Marks, David R.; Arsnoe, Dustin M.; Bevins, Sarah N.; Wang, Eryu; Weaver, Scott C.; Mickley, Randall M.; DeLiberto, Thomas J.

2014-01-01

Mute swans (Cygnus olor) are an invasive species in the United States. The dramatic increase in their populations in localized areas has led to various problems, among them competition with native species and attacks on humans by aggressive swans. However, very little is known about the ability of these swans to transmit pathogens to humans, domestic birds, or wildlife or participate in enzootic maintenance. To learn more about select pathogens that mute swans may harbor, a survey was conducted from April of 2011 to August of 2012 in the Great Lakes region and localized areas of the Atlantic coast, which revealed serologic evidence of arbovirus exposure in mute swans. Of 497 mute swans tested, antibodies were detected for eastern equine encephalitis (4.8%), St. Louis encephalitis (1.4%), West Nile (1.2%), and Turlock (0.6%) viruses. Samples were also tested for evidence of antibodies to La Crosse virus, but none were positive. PMID:25266351

Guillain-Barré Syndrome Associated With Zika Virus Infection in Martinique in 2016: A Prospective Study.

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Rozé, Benoît; Najioullah, Fatiha; Fergé, Jean-Louis; Dorléans, Frédérique; Apetse, Kossivi; Barnay, Jose-Luis; Daudens-Vaysse, Elise; Brouste, Yannick; Césaire, Raymond; Fagour, Laurence; Valentino, Ruddy; Ledrans, Martine; Mehdaoui, Hossein; Abel, Sylvie; Leparc-Goffart, Isabelle; Signate, Aissatou; Cabié, André

2017-10-16

Guillain-Barré syndrome (GBS) has been reported to be associated with Zika virus (ZIKV) infection in case reports and retrospective studies, mostly on the basis of serological tests, with the problematic cross-reacting antibodies of the Flavivirus genus. Some GBS cases do not exhibit a high level of diagnostic certainty. This prospective study aimed to describe the clinical profiles and the frequency of GBS associated with ZIKV during the ZIKV outbreak in Martinique in 2016. We recorded prospective data from GBS meeting levels 1 or 2 of diagnostic certainty for the Brighton Collaboration, with proof of recent ZIKV infection and negative screening for etiologies of GBS. Of the sample of 34 patients with suspected GBS during the outbreak, 30 had a proven presence of GBS, and 23 had a recent ZIKV infection. The estimated GBS incidence rate ratio (2016 vs 2006-2015) was 4.52 (95% confidence interval, 2.80-7.64; P = .0001). Recent ZIKV infection was confirmed by urine reverse-transcription polymerase chain reaction (RT-PCR) analysis in 17 cases and by serology in 6 cases. Patients, 65% of whom were male, had a median age of 61 years (interquartile range, 56-71 years) and experienced severe GBS. Electrophysiological tests were consistent with the primary demyelinating form of the disease. ZIKV infection is usually benign, when symptomatic, but in countries at risk of ZIKV epidemics, adequate intensive care bed capacity is required for management of severe GBS cases. Arbovirus RNA detection by RT-PCR should be part of the management of GBS cases. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Comparison of dengue virus type 2-specific small RNAs from RNA interference-competent and -incompetent mosquito cells.

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Jaclyn C Scott

2010-10-01

Full Text Available The exogenous RNA interference (RNAi pathway is an important antiviral defense against arboviruses in mosquitoes, and virus-specific small interfering (siRNAs are key components of this pathway. Understanding the biogenesis of siRNAs in mosquitoes could have important ramifications in using RNAi to control arbovirus transmission. Using deep sequencing technology, we characterized dengue virus type 2 (DENV2-specific small RNAs produced during infection of Aedes aegypti mosquitoes and A. aegypti Aag2 cell cultures and compared them to those produced in the C6/36 Aedes albopictus cell line. We show that the size and mixed polarity of virus-specific small RNAs from DENV-infected A. aegypti cells indicate that they are products of Dicer-2 (Dcr2 cleavage of long dsRNA, whereas C6/36 cells generate DENV2-specific small RNAs that are longer and predominantly positive polarity, suggesting that they originate from a different small RNA pathway. Examination of virus-specific small RNAs after infection of the two mosquito cell lines with the insect-only flavivirus cell fusing agent virus (CFAV corroborated these findings. An in vitro assay also showed that Aag2 A. aegypti cells are capable of siRNA production, while C6/36 A. albopictus cells exhibit inefficient Dcr2 cleavage of long dsRNA. Defective expression or function of Dcr2, the key initiator of the RNAi pathway, might explain the comparatively robust growth of arthropod-borne viruses in the C6/36 cell line, which has been used frequently as a surrogate for studying molecular interactions between arboviruses and cells of their mosquito hosts.

The Detection of Spotted Fever Group Rickettsia DNA in Tick Samples From Pastoral Communities in Kenya.

Science.gov (United States)

Koka, Hellen; Sang, Rosemary; Kutima, Helen Lydia; Musila, Lillian

2017-05-01

In this study, ticks from pastoral communities in Kenya were tested for Rickettsia spp. infections in geographical regions where the presence of tick-borne arboviruses had previously been reported. Rickettsial and arbovirus infections have similar clinical features which makes differential diagnosis challenging when both diseases occur. The tick samples were tested for Rickettsia spp. by conventional PCR using three primer sets targeting the gltA, ompA, and ompB genes followed by amplicon sequencing. Of the tick pools screened, 25% (95/380) were positive for Rickettsia spp. DNA using the gltA primer set. Of the tick-positive pools, 60% were ticks collected from camels. Rickettsia aeschlimannii and R. africae were the main Rickettsia spp. detected in the tick pools sequenced. The findings of this study indicate that multiple Rickettsia species are circulating in ticks from pastoral communities in Kenya and could contribute to the etiology of febrile illness in these areas. Diagnosis and treatment of rickettsial infections should be a public health priority in these regions. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

First report of naturally infected Aedes aegypti with chikungunya virus genotype ECSA in the Americas.

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Costa-da-Silva, André Luis; Ioshino, Rafaella Sayuri; Petersen, Vivian; Lima, Antonio Fernando; Cunha, Marielton Dos Passos; Wiley, Michael R; Ladner, Jason T; Prieto, Karla; Palacios, Gustavo; Costa, Danuza Duarte; Suesdek, Lincoln; Zanotto, Paolo Marinho de Andrade; Capurro, Margareth Lara

2017-06-01

The worldwide expansion of new emergent arboviruses such as Chikungunya and Zika reinforces the importance in understanding the role of mosquito species in spreading these pathogens in affected regions. This knowledge is essential for developing effective programs based on species specificity to avoid the establishment of endemic transmission cycles sustained by the identified local vectors. Although the first autochthonous transmission of Chikungunya virus was described in 2014 in the north of Brazil, the main outbreaks were reported in 2015 and 2016 in the northeast of Brazil. During 5 days of February 2016, we collected mosquitoes in homes of 6 neighborhoods of Aracaju city, the capital of Sergipe state. Four mosquito species were identified but Culex quinquefasciatus and Aedes aegypti were the most abundant. Field-caught mosquitoes were tested for Chikungunya (CHIKV), Zika (ZIKV) and Dengue viruses (DENV) by qRT-PCR and one CHIKV-infected Ae. aegypti female was detected. The complete sequence of CHIKV genome was obtained from this sample and phylogenetic analysis revealed that this isolate belongs to the East-Central-South-African (ECSA) genotype. Our study describes the first identification of a naturally CHIKV-infected Ae. aegypti in Brazil and the first report of a CHIKV from ECSA genotype identified in this species in the Americas. These findings support the notion of Ae. aegypti being a vector involved in CHIKV outbreaks in northeast of Brazil.

First report of naturally infected Aedes aegypti with chikungunya virus genotype ECSA in the Americas.

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André Luis Costa-da-Silva

2017-06-01

Full Text Available The worldwide expansion of new emergent arboviruses such as Chikungunya and Zika reinforces the importance in understanding the role of mosquito species in spreading these pathogens in affected regions. This knowledge is essential for developing effective programs based on species specificity to avoid the establishment of endemic transmission cycles sustained by the identified local vectors. Although the first autochthonous transmission of Chikungunya virus was described in 2014 in the north of Brazil, the main outbreaks were reported in 2015 and 2016 in the northeast of Brazil.During 5 days of February 2016, we collected mosquitoes in homes of 6 neighborhoods of Aracaju city, the capital of Sergipe state. Four mosquito species were identified but Culex quinquefasciatus and Aedes aegypti were the most abundant. Field-caught mosquitoes were tested for Chikungunya (CHIKV, Zika (ZIKV and Dengue viruses (DENV by qRT-PCR and one CHIKV-infected Ae. aegypti female was detected. The complete sequence of CHIKV genome was obtained from this sample and phylogenetic analysis revealed that this isolate belongs to the East-Central-South-African (ECSA genotype.Our study describes the first identification of a naturally CHIKV-infected Ae. aegypti in Brazil and the first report of a CHIKV from ECSA genotype identified in this species in the Americas. These findings support the notion of Ae. aegypti being a vector involved in CHIKV outbreaks in northeast of Brazil.

Urbanization and geographic expansion of zoonotic arboviral diseases: mechanisms and potential strategies for prevention

OpenAIRE

Weaver, Scott C.

2013-01-01

Arthropod-borne viruses (arboviruses) mainly infect people via direct spillover from enzootic cycles. However, dengue, chikungunya, and yellow fever viruses have repeatedly initiated urban transmission cycles involving human amplification and peridomestic mosquito vectors to cause major epidemics. Here, I review these urban emergences and potential strategies for their prevention and control.

Wolbachia Blocks Viral Genome Replication Early in Infection without a Transcriptional Response by the Endosymbiont or Host Small RNA Pathways.

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Stephanie M Rainey

2016-04-01

Full Text Available The intracellular endosymbiotic bacterium Wolbachia can protect insects against viral infection, and is being introduced into mosquito populations in the wild to block the transmission of arboviruses that infect humans and are a major public health concern. To investigate the mechanisms underlying this antiviral protection, we have developed a new model system combining Wolbachia-infected Drosophila melanogaster cell culture with the model mosquito-borne Semliki Forest virus (SFV; Togaviridae, Alphavirus. Wolbachia provides strong antiviral protection rapidly after infection, suggesting that an early stage post-infection is being blocked. Wolbachia does appear to have major effects on events distinct from entry, assembly or exit as it inhibits the replication of an SFV replicon transfected into the cells. Furthermore, it causes a far greater reduction in the expression of proteins from the 3' open reading frame than the 5' non-structural protein open reading frame, indicating that it is blocking the replication of viral RNA. Further to this separation of the replicase proteins and viral RNA in transreplication assays shows that uncoupling of viral RNA and replicase proteins does not overcome Wolbachia's antiviral activity. This further suggests that replicative processes are disrupted, such as translation or replication, by Wolbachia infection. This may occur by Wolbachia mounting an active antiviral response, but the virus did not cause any transcriptional response by the bacterium, suggesting that this is not the case. Host microRNAs (miRNAs have been implicated in protection, but again we found that host cell miRNA expression was unaffected by the bacterium and neither do our findings suggest any involvement of the antiviral siRNA pathway. We conclude that Wolbachia may directly interfere with early events in virus replication such as translation of incoming viral RNA or RNA transcription, and this likely involves an intrinsic (as opposed to

Epidemiologia das encefalites por arbovírus na amazônia brasileira Epidemiology of encephalitis by arboviruses in the Amazon region of Brazil

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Pedro Fernando da Costa Vasconcelos

1991-12-01

outbreaks of human diseases caused by arboviruses had been detected. These viruses are widespread in all Amazonia, and at least four of them, EEE, WEE, SLE and MUC are pathogenic to man. EEE and WEE infections were detected by serology, while SLE and MUC by either serology and virus isolation. The PIX virus has the lowest prevalence and, it was isolated in only a few cases, one being from a laboratory infection. Wild birds are the main hosts for all these viruses, except MUC, whose major hosts are rodents. The symptoms presented by infected people were generally a mild febrile illness. Although, jaundice was observed in two individuals from whom SLE was isolated. A comparison of the clinical symptoms presented by the patients in the Amazon Region and other areas of America, especially in the USA is made. In Brazilian Amazon region epidemics have not been detected although, at least, one EEE epizootic was recorded in Bragança, Para State, in 1960. At that time, of 500 horses that were examined 61% were positive to EEE by HI and of mem 8.2% died On the other hand. SLE has caused four epizootics in a forest near Belem. Wild birds and sentinel monkeys were infected, but no human cases were reported.

Aedes-Borne Virus-Mosquito Interactions: Mass Spectrometry Strategies and Findings.

Science.gov (United States)

Pando-Robles, Victoria; Batista, Cesar V

2017-06-01

Aedes-borne viruses are responsible for high-impact neglected tropical diseases and unpredictable outbreaks such as the ongoing Zika epidemics. Aedes mosquitoes spread different arboviruses such as Dengue virus (DENV), Chikungunya virus (CHIKV), and Zika virus, among others, and are responsible for the continuous emergence and reemergence of these pathogens. These viruses have complex transmission cycles that include two hosts, namely the Aedes mosquito as a vector and susceptible vertebrate hosts. Human infection with arboviruses causes diseases that range from subclinical or mild to febrile diseases, encephalitis, and hemorrhagic fever. Infected mosquitoes do not show detectable signs of disease, even though the virus maintains a lifelong persistent infection. The infection of the Aedes mosquito by viruses involves a molecular crosstalk between cell and viral proteins. An understanding of how mosquito vectors and viruses interact is of fundamental interest, and it also offers novel perspectives for disease control. In recent years, mass spectrometry (MS)-based strategies in combination with bioinformatics have been successfully applied to identify and quantify global changes in cellular proteins, lipids, peptides, and metabolites in response to viral infection. Although the information about proteomics in the Aedes mosquito is limited, the information that has been reported can set up the basis for future studies. This review reflects how MS-based approaches have extended our understanding of Aedes mosquito biology and the development of DENV and CHIKV infection in the vector. Finally, this review discusses future challenges in the field.

A Serological Protein Microarray for Detection of Multiple Cross-Reactive Flavivirus Infections in Horses for Veterinary and Public Health Surveillance.

Science.gov (United States)

Cleton, N B; van Maanen, K; Bergervoet, S A; Bon, N; Beck, C; Godeke, G-J; Lecollinet, S; Bowen, R; Lelli, D; Nowotny, N; Koopmans, M P G; Reusken, C B E M

2017-12-01

The genus Flavivirus in the family Flaviviridae includes some of the most important examples of emerging zoonotic arboviruses that are rapidly spreading across the globe. Japanese encephalitis virus (JEV), West Nile virus (WNV), St. Louis encephalitis virus (SLEV) and Usutu virus (USUV) are mosquito-borne members of the JEV serological group. Although most infections in humans are asymptomatic or present with mild flu-like symptoms, clinical manifestations of JEV, WNV, SLEV, USUV and tick-borne encephalitis virus (TBEV) can include severe neurological disease and death. In horses, infection with WNV and JEV can lead to severe neurological disease and death, while USUV, SLEV and TBEV infections are mainly asymptomatic, however, and induce antibody responses. Horses often serve as sentinels to monitor active virus circulation in serological surveillance programmes specifically for WNV, USUV and JEV. Here, we developed and validated a NS1-antigen protein microarray for the serological differential diagnosis of flavivirus infections in horses using sera of experimentally and naturally infected symptomatic as well as asymptomatic horses. Using samples from experimentally infected horses, an IgG and IgM specificity of 100% and a sensitivity of 95% for WNV and 100% for JEV was achieved with a cut-off titre of 1 : 20 based on ROC calculation. In field settings, the microarray identified 93-100% of IgG-positive horses with recent WNV infections and 87% of TBEV IgG-positive horses. WNV IgM sensitivity was 80%. Differentiation between closely related flaviviruses by the NS1-antigen protein microarray is possible, even though we identified some instances of cross-reactivity among antibodies. However, the assay is not able to differentiate between naturally infected horses and animals vaccinated with an inactivated WNV whole-virus vaccine. We showed that the NS1-microarray can potentially be used for diagnosing and distinguishing flavivirus infections in horses and for public

A molecular survey of acute febrile illnesses reveals Plasmodium vivax infections in Kedougou, southeastern Senegal.

Science.gov (United States)

Niang, Makhtar; Thiam, Laty Gaye; Sow, Abdourahmane; Loucoubar, Cheikh; Bob, Ndeye Sakha; Diop, Fode; Diouf, Babacar; Niass, Oumy; Mansourou, Annick; Varela, Marie Louise; Perraut, Ronald; Sall, Amadou A; Toure-Balde, Aissatou

2015-07-19

Control efforts towards malaria due to Plasmodium falciparum significantly decreased the incidence of the disease in many endemic countries including Senegal. Surprisingly, in Kedougou (southeastern Senegal) P. falciparum malaria remains highly prevalent and the relative contribution of other Plasmodium species to the global malaria burden is very poorly documented, partly due to the low sensitivity of routine diagnostic tools. Molecular methods offer better estimate of circulating Plasmodium species in a given area. A molecular survey was carried out to document circulating malaria parasites in Kedougou region. A total of 263 long-term stored sera obtained from patients presenting with acute febrile illness in Kedougou between July 2009 and July 2013 were used for malaria parasite determination. Sera were withdrawn from a collection established as part of a surveillance programme of arboviruses infections in the region. Plasmodium species were characterized by a nested PCR-based approach targeting the 18S small sub-unit ribosomal RNA genes of Plasmodium spp. Of the 263 sera screened in this study, Plasmodium genomic DNA was amplifiable by nested PCR from 62.35% (164/263) of samples. P. falciparum accounted for the majority of infections either as single in 85.97% (141/164) of Plasmodium-positive samples or mixed with Plasmodium ovale (11.58%, 19/164) or Plasmodium vivax (1.21%, 2/164). All 19 (11.58%) P. ovale-infected patients were mixed with P. falciparum, while no Plasmodium malariae was detected in this survey. Four patients (2.43%) were found to be infected by P. vivax, two of whom were mixed with P. falciparum. P. vivax infections originated from Bandafassi and Ninefesha villages and concerned patients aged 4, 9, 10, and 15 years old, respectively. DNA sequences alignment and phylogenetic analysis demonstrated that sequences from Kedougou corresponded to P. vivax, therefore confirming the presence of P. vivax infections in Senegal. The results confirm the

Zika virus infection during pregnancy and microcephaly occurrence: a review of literature and Brazilian data.

Science.gov (United States)

De Carvalho, Newton Sérgio; De Carvalho, Beatriz Freitas; Fugaça, Cyllian Arias; Dóris, Bruna; Biscaia, Evellyn Silverio

2016-01-01

In November of 2015, the Ministry of Health of Brazil published an announcement confirming the relationship between Zika virus and the microcephaly outbreak in the Northeast, suggesting that infected pregnant women might have transmitted the virus to their fetuses. The objectives of this study were to conduct a literature review about Zika virus infection and microcephaly, evaluate national and international epidemiological data, as well as the current recommendations for the health teams. Zika virus is an arbovirus, whose main vector is the Aedes sp. The main symptoms of the infection are maculopapular rash, fever, non-purulent conjunctivitis, and arthralgia. Transmission of this pathogen occurs mainly by mosquito bite, but there are also reports via the placenta. Microcephaly is defined as a measure of occipto-frontal circumference being more than two standard deviations below the mean for age and gender. The presence of microcephaly demands evaluation of the patient, in order to diagnose the etiology. Health authorities issued protocols, reports and notes concerning the management of microcephaly caused by Zika virus, but there is still controversy about managing the cases. The Ministry of Health advises notifying any suspected or confirmed cases of children with microcephaly related to the pathogen, which is confirmed by a positive specific laboratory test for the virus. The first choice for imaging exam in children with this malformation is transfontanellar ultrasound. The most effective way to control this outbreak of microcephaly probably caused by this virus is to combat the vector. Since there is still uncertainty about the period of vulnerability of transmission via placenta, the use of repellents is crucial throughout pregnancy. More investigations studying the consequences of this viral infection on the body of newborns and in their development are required. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

Zika virus: An updated review of competent or naturally infected mosquitoes.

Science.gov (United States)

Epelboin, Yanouk; Talaga, Stanislas; Epelboin, Loïc; Dusfour, Isabelle

2017-11-01

Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) that recently caused outbreaks in the Americas. Over the past 60 years, this virus has been observed circulating among African, Asian, and Pacific Island populations, but little attention has been paid by the scientific community until the discovery that large-scale urban ZIKV outbreaks were associated with neurological complications such as microcephaly and several other neurological malformations in fetuses and newborns. This paper is a systematic review intended to list all mosquito species studied for ZIKV infection or for their vector competence. We discuss whether studies on ZIKV vectors have brought enough evidence to formally exclude other mosquitoes than Aedes species (and particularly Aedes aegypti) to be ZIKV vectors. From 1952 to August 15, 2017, ZIKV has been studied in 53 mosquito species, including 6 Anopheles, 26 Aedes, 11 Culex, 2 Lutzia, 3 Coquillettidia, 2 Mansonia, 2 Eretmapodites, and 1 Uranotaenia. Among those, ZIKV was isolated from 16 different Aedes species. The only species other than Aedes genus for which ZIKV was isolated were Anopheles coustani, Anopheles gambiae, Culex perfuscus, and Mansonia uniformis. Vector competence assays were performed on 22 different mosquito species, including 13 Aedes, 7 Culex, and 2 Anopheles species with, as a result, the discovery that A. aegypti and Aedes albopictus were competent for ZIKV, as well as some other Aedes species, and that there was a controversy surrounding Culex quinquefasciatus competence. Although Culex, Anopheles, and most of Aedes species were generally observed to be refractory to ZIKV infection, other potential vectors transmitting ZIKV should be explored.

Zika virus: An updated review of competent or naturally infected mosquitoes

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Talaga, Stanislas; Epelboin, Loïc; Dusfour, Isabelle

2017-01-01

Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) that recently caused outbreaks in the Americas. Over the past 60 years, this virus has been observed circulating among African, Asian, and Pacific Island populations, but little attention has been paid by the scientific community until the discovery that large-scale urban ZIKV outbreaks were associated with neurological complications such as microcephaly and several other neurological malformations in fetuses and newborns. This paper is a systematic review intended to list all mosquito species studied for ZIKV infection or for their vector competence. We discuss whether studies on ZIKV vectors have brought enough evidence to formally exclude other mosquitoes than Aedes species (and particularly Aedes aegypti) to be ZIKV vectors. From 1952 to August 15, 2017, ZIKV has been studied in 53 mosquito species, including 6 Anopheles, 26 Aedes, 11 Culex, 2 Lutzia, 3 Coquillettidia, 2 Mansonia, 2 Eretmapodites, and 1 Uranotaenia. Among those, ZIKV was isolated from 16 different Aedes species. The only species other than Aedes genus for which ZIKV was isolated were Anopheles coustani, Anopheles gambiae, Culex perfuscus, and Mansonia uniformis. Vector competence assays were performed on 22 different mosquito species, including 13 Aedes, 7 Culex, and 2 Anopheles species with, as a result, the discovery that A. aegypti and Aedes albopictus were competent for ZIKV, as well as some other Aedes species, and that there was a controversy surrounding Culex quinquefasciatus competence. Although Culex, Anopheles, and most of Aedes species were generally observed to be refractory to ZIKV infection, other potential vectors transmitting ZIKV should be explored. PMID:29145400

Short report: Antibody prevalence of select arboviruses in mute swans (Cygnus olor) in the Great Lakes region and Atlantic coast of the United States.

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Pedersen, Kerri; Marks, David R; Arsnoe, Dustin M; Bevins, Sarah N; Wang, Eryu; Weaver, Scott C; Mickley, Randall M; DeLiberto, Thomas J

2014-12-01

Mute swans (Cygnus olor) are an invasive species in the United States. The dramatic increase in their populations in localized areas has led to various problems, among them competition with native species and attacks on humans by aggressive swans. However, very little is known about the ability of these swans to transmit pathogens to humans, domestic birds, or wildlife or participate in enzootic maintenance. To learn more about select pathogens that mute swans may harbor, a survey was conducted from April of 2011 to August of 2012 in the Great Lakes region and localized areas of the Atlantic coast, which revealed serologic evidence of arbovirus exposure in mute swans. Of 497 mute swans tested, antibodies were detected for eastern equine encephalitis (4.8%), St. Louis encephalitis (1.4%), West Nile (1.2%), and Turlock (0.6%) viruses. Samples were also tested for evidence of antibodies to La Crosse virus, but none were positive. © The American Society of Tropical Medicine and Hygiene.

Aedes (Stegomyia albopictus (Skuse: a potential vector of Zika virus in Singapore.

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Pei-Sze Jeslyn Wong

Full Text Available Zika virus (ZIKV is a little known arbovirus until it caused a major outbreak in the Pacific Island of Yap in 2007. Although the virus has a wide geographic distribution, most of the known vectors are sylvatic Aedes mosquitoes from Africa where the virus was first isolated. Presently, Ae. aegypti is the only known vector to transmit the virus outside the African continent, though Ae. albopictus has long been a suspected vector. Currently, Ae. albopictus has been shown capable of transmitting more than 20 arboviruses and its notoriety as an important vector came to light during the recent chikungunya pandemic. The vulnerability of Singapore to emerging infectious arboviruses has stimulated our interest to determine the competence of local Ae. albopictus to transmit ZIKV.To determine the competence of Ae. albopictus to ZIKV, we orally infected local mosquito strains to a Ugandan strain virus. Fully engorged mosquitoes were maintained in an environmental chamber set at 29°C and 80-85%RH. Twelve mosquitoes were then sampled daily from day one to seven and on day 10 and 14 post infection (pi. Zika virus titre in the midgut and salivary glands of each mosquito were determined using tissue culture infectious dose50 assay, while transmissibility of the virus was determined by detecting viral antigen in the mosquito saliva by qRT-PCR. High dissemination and transmission rate of ZIKV were observed. By day 7-pi, all mosquitoes have disseminated infection and 73% of these mosquitoes have ZIKV in their saliva. By day 10-pi, all mosquitoes were potentially infectious.The study highlighted the potential of Ae. albopictus to transmit ZIKV and the possibility that the virus could be established locally. Nonetheless, the threat of ZIKV can be mitigated by existing dengue and chikungunya control program being implemented in Singapore.

Reconstruction of the Evolutionary History and Dispersal of Usutu Virus, a Neglected Emerging Arbovirus in Europe and Africa.

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Engel, Dimitri; Jöst, Hanna; Wink, Michael; Börstler, Jessica; Bosch, Stefan; Garigliany, Mutien-Marie; Jöst, Artur; Czajka, Christina; Lühken, Renke; Ziegler, Ute; Groschup, Martin H; Pfeffer, Martin; Becker, Norbert; Cadar, Daniel; Schmidt-Chanasit, Jonas

2016-02-02

Usutu virus (USUV), one of the most neglected Old World encephalitic flaviviruses, causes epizootics among wild and captive birds and sporadic infection in humans. The dynamics of USUV spread and evolution in its natural hosts are unknown. Here, we present the phylogeny and evolutionary history of all available USUV strains, including 77 newly sequenced complete genomes from a variety of host species at a temporal and spatial scaled resolution. The results showed that USUV can be classified into six distinct lineages and that the most recent common ancestor of the recent European epizootics emerged in Africa at least 500 years ago. We demonstrated that USUV was introduced regularly from Africa into Europe in the last 50 years, and the genetic diversity of European lineages is shaped primarily by in situ evolution, while the African lineages have been driven by extensive gene flow. Most of the amino acid changes are deleterious polymorphisms removed by purifying selection, with adaptive evolution restricted to the NS5 gene and several others evolving under episodic directional selection, indicating that the ecological or immunological factors were mostly the key determinants of USUV dispersal and outbreaks. Host-specific mutations have been detected, while the host transition analysis identified mosquitoes as the most likely origin of the common ancestor and birds as the source of the recent European USUV lineages. Our results suggest that the major migratory bird flyways could predict the continental and intercontinental dispersal patterns of USUV and that migratory birds might act as potential long-distance dispersal vehicles. Usutu virus (USUV), a mosquito-borne flavivirus of the Japanese encephalitis virus antigenic group, caused massive bird die-offs, mostly in Europe. There is increasing evidence that USUV appears to be pathogenic for humans, becoming a potential public health problem. The emergence of USUV in Europe allows us to understand how an arbovirus

A review on Zika virus, a re-emerging arbovirus: review article

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Farshad Khodakhah

2018-02-01

Full Text Available Before the recent outbreaks of Zika virus, few people have ever heard of its name. Even virologists had paid little attention to this member of the Flaviviridae family. Hence, up to January 2016, only 269 articles about Zika virus had been indexed in PubMed compared to the 9187 articles related to dengue virus. However, declaration of the World health organization (WHO about the global Zika virus spreading, which has been associated with birth defects and some neurological problems, diverted more attention to this forgotten virus. Afterwards, the virus hit the headlines and became a research interest. Since then, up to 9 August 2017, the number of Zika related articles indexed in PubMed reached to 3214. Zika virus is a re-emerging arbovirus. The First detection of Zika virus was in Uganda in 1947. It belongs to the Flavivirus genus in the Flaviviridae family. Zika can typically cause a mild and self-limiting disease in a healthy person. However, in pregnant women, it might cause birth defects and occasionally it can be associated with peripheral neuropathy such as Guillain-Barre syndrome. Although many research have been conducted to find out the casual link between this virus and these disorders but this relationship is still dim and controversial. Considering its recent epidemics in 2015 and 2016 the geographical distribution of Zika virus seems to expand all over the world progressively. Interaction between virus and vector is dynamic. Variety of competent vectors and adaptability of virus to new arthropod vectors are the two major factors for this process. According to the last report published by WHO, 84 countries/territories in five continents have reported the circulation of Zika virus in their area. In the recent outbreak, WHO regional office in our region (EMRO have reported no case of Zika virus transmission from this region. Nonetheless, because specific and competent vectors exist in some countries, this region has a potential of

[Zika virus infection: a new public health emergency with great media impact].

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Caylà, Joan A; Domínguez, Ángela; Rodríguez Valín, Elena; de Ory, Fernando; Vázquez, Ana; Fortuny, Claudia

Infection with Zika virus (ZV) has become a new epidemic, with great impact on the media, and is having a strong effect in Latin American countries. Its possible association with microcephaly and Guillain-Barré syndrome prompted the World Health Organization (WHO) to declare on 1 February 2016 that this epidemic is a public health emergency of international concern. Epidemiological data show an increasing incidence in countries like Brazil and Colombia, and that the epidemic is still expanding in many other countries. Between January 2007 and 27 April 2016, the WHO detected transmission in 55 countries (in 42 of these, this was the first outbreak of Zika) and 1,198 microcephalies and other neurological disorders in Brazil. Also, during 2015-2016, 13 countries detected an increase in Guillain-Barré syndrome and/or confirmation of ZV associated with Guillain-Barré syndrome. Research has already demonstrated a causal relationship between microcephaly and other serious brain disorders in newborns and ZV infection in the mother. Clinically, many cases are asymptomatic and it can be difficult to distinguish this diagnosis from that of other arboviruses. Vector control in Spain is a priority because of the presence of the Aedes albopictus (tiger mosquito). Early diagnosis is recommended, as is avoiding travel to endemic areas and unprotected sex, and ensuring that the high political profile, which can prevent this epidemic from becoming a high prevalence endemic disease, does not cause us to forget about other health problems. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

Synergized resmethrin and corticosterone alter the chicken's response to west nile virus

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Jankowski, Mark David [Los Alamos National Laboratory; Franson, J Christian [US GEOLOGICAL SURVEY; Mostl, Erich [UNIV OF VIENNA; Porter, Warren P [UNIV OF WISCONSIN; Hofmeister, Erik K [US GEOLOGICAL SURVEY

2009-01-01

Debate concerning arbovirus control strategies remains contentious because concern regarding the relative risk of viral infection and environmental toxicant exposure is high but inadequately characterized. Taking this into account, mosquito control agencies employ aerial insecticides only after arbovirus surveillance data indicate high local mosquito-infection-rates. Successfully mitigating the risk of adult-mosquito-control insecticides ('adulticides') to non-target species such as humans, domestic animals, fish, beneficial insects and wildlife, while increasing their efficacy to reduce arbovirus outbreak intensity requires targeted scientific data from animal toxicity studies and environmental monitoring activities. Wild birds are an important reservoir host for WNv and are potentially exposed to insecticides used for mosquito control. However, no risk assessments have evaluated whether insecticides augment or extend the potential transmissibility of West Nile virus (WNv) in birds. In order to augment existing resmethrin risk assessments, we aimed to determine whether synergized resmethrin (SR) may cause chickens to develop an elevated or extended WN viremia and if subacute stress may affect its immunotoxicity. We distributed 40 chickens into four groups then exposed them prior to and during WNv infection with SR (50 {mu}g/l resmethrin + 150 {mu}g/l piperonyl butoxide) and/or 20 mg/I corticosterone (CORT) in their drinking-water. Corticosterone was given for 10 continuous days and SR was given for 3 alternate days starting the 3rd day of CORT exposure, then chickens were subcutaneously inoculated with WNv on the 5th day of CORT treatment. Compared to controls, CORT treatment extended and elevated viremia, enhanced WNv-specific antibody and increased the percentage of birds that shed oral virus, whereas SR treatment extended viremia, depressed WNv-specific IgG, and increased the percentage of CORT-treated birds that shed oral virus. Corticosterone and SR

Spread of Zika virus:The key role of mosquito vector control

Institute of Scientific and Technical Information of China (English)

Giovanni Benelli

2016-01-01

Mosquitoes (Diptera: Culicidae) represent a key threat for millions of humans and ani-mals worldwide, since they act as vectors for important parasites and pathogens, including malaria, filariasis and a wide number of arboviruses. The recent outbreaks of Zika virus infections occurring in South America, Central America, and the Caribbean, represent the most recent four arrivals of important arboviruses in the western hemi-sphere, over the last 20 years, namely dengue, West Nile virus, and chikungunya. Since there are no specific treatments for Zika virus and the other arboviruses mentioned above, it should be highlighted that the eco-friendly and effective control of mosquito vectors is of pivotal importance. Besides radiation, transgenic and symbiont-based mosquito control approaches, an effective option may be the employ of biological control agents of mosquito young instars, in presence of ultra-low quantities of green-synthesized nano-particles, which magnify their predation efficiency. Furthermore, behaviour-based control tools relying on the employ of swarming behaviour manipulation (i.e. the“lure and kill”approach), pheromone traps, sound traps need further research attention. In particular, detailed basic information on the physical and chemical cues routing mosquito swarming and mating dynamics is urgently required.

Spread of Zika virus:The key role of mosquito vector control

Institute of Scientific and Technical Information of China (English)

Giovanni Benelli

2016-01-01

Mosquitoes(Diptera: Culicidae) represent a key threat for millions of humans and animals worldwide, since they act as vectors for important parasites and pathogens,including malaria, filariasis and a wide number of arboviruses. The recent outbreaks of Zika virus infections occurring in South America, Central America, and the Caribbean,represent the most recent four arrivals of important arboviruses in the western hemisphere, over the last 20 years, namely dengue, West Nile virus, and chikungunya. Since there are no specific treatments for Zika virus and the other arboviruses mentioned above,it should be highlighted that the eco-friendly and effective control of mosquito vectors is of pivotal importance. Besides radiation, transgenic and symbiont-based mosquito control approaches, an effective option may be the employ of biological control agents of mosquito young instars, in presence of ultra-low quantities of green-synthesized nanoparticles, which magnify their predation efficiency. Furthermore, behaviour-based control tools relying on the employ of swarming behaviour manipulation(i.e. the "lure and kill"approach), pheromone traps, sound traps need further research attention. In particular,detailed basic information on the physical and chemical cues routing mosquito swarming and mating dynamics is urgently required.

Spread of Zika virus: The key role of mosquito vector control

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Giovanni Benelli

2016-06-01

Full Text Available Mosquitoes (Diptera: Culicidae represent a key threat for millions of humans and animals worldwide, since they act as vectors for important parasites and pathogens, including malaria, filariasis and a wide number of arboviruses. The recent outbreaks of Zika virus infections occurring in South America, Central America, and the Caribbean, represent the most recent four arrivals of important arboviruses in the western hemisphere, over the last 20 years, namely dengue, West Nile virus, and chikungunya. Since there are no specific treatments for Zika virus and the other arboviruses mentioned above, it should be highlighted that the eco-friendly and effective control of mosquito vectors is of pivotal importance. Besides radiation, transgenic and symbiont-based mosquito control approaches, an effective option may be the employ of biological control agents of mosquito young instars, in presence of ultra-low quantities of green-synthesized nanoparticles, which magnify their predation efficiency. Furthermore, behaviour-based control tools relying on the employ of swarming behaviour manipulation (i.e. the “lure and kill” approach, pheromone traps, sound traps need further research attention. In particular, detailed basic information on the physical and chemical cues routing mosquito swarming and mating dynamics is urgently required.

Quantitative Proteomic Analysis of Mosquito C6/36 Cells Reveals Host Proteins Involved in Zika Virus Infection.

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Xin, Qi-Lin; Deng, Cheng-Lin; Chen, Xi; Wang, Jun; Wang, Shao-Bo; Wang, Wei; Deng, Fei; Zhang, Bo; Xiao, Gengfu; Zhang, Lei-Ke

2017-06-15

Zika virus (ZIKV) is an emerging arbovirus belonging to the genus Flavivirus of the family Flaviviridae During replication processes, flavivirus manipulates host cell systems to facilitate its replication, while the host cells activate antiviral responses. Identification of host proteins involved in the flavivirus replication process may lead to the discovery of antiviral targets. The mosquitoes Aedes aegypti and Aedes albopictus are epidemiologically important vectors for ZIKV, and effective restrictions of ZIKV replication in mosquitoes will be vital in controlling the spread of virus. In this study, an iTRAQ-based quantitative proteomic analysis of ZIKV-infected Aedes albopictus C6/36 cells was performed to investigate host proteins involved in the ZIKV infection process. A total of 3,544 host proteins were quantified, with 200 being differentially regulated, among which CHCHD2 can be upregulated by ZIKV infection in both mosquito C6/36 and human HeLa cells. Our further study indicated that CHCHD2 can promote ZIKV replication and inhibit beta interferon (IFN-β) production in HeLa cells, suggesting that ZIKV infection may upregulate CHCHD2 to inhibit IFN-I production and thus promote virus replication. Bioinformatics analysis of regulated host proteins highlighted several ZIKV infection-regulated biological processes. Further study indicated that the ubiquitin proteasome system (UPS) plays roles in the ZIKV entry process and that an FDA-approved inhibitor of the 20S proteasome, bortezomib, can inhibit ZIKV infection in vivo Our study illustrated how host cells respond to ZIKV infection and also provided a candidate drug for the control of ZIKV infection in mosquitoes and treatment of ZIKV infection in patients. IMPORTANCE ZIKV infection poses great threats to human health, and there is no FDA-approved drug available for the treatment of ZIKV infection. During replication, ZIKV manipulates host cell systems to facilitate its replication, while host cells activate

Urbanization and geographic expansion of zoonotic arboviral diseases: mechanisms and potential strategies for prevention.

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Weaver, Scott C

2013-08-01

Arthropod-borne viruses (arboviruses) mainly infect people via direct spillover from enzootic cycles. However, dengue, chikungunya, and yellow fever viruses have repeatedly initiated urban transmission cycles involving human amplification and peridomestic mosquito vectors to cause major epidemics. Here, I review these urban emergences and potential strategies for their prevention and control. Copyright © 2013 Elsevier Ltd. All rights reserved.

Arboviral diseases in the Western Brazilian Amazon: a perspective and analysis from a tertiary health & research center in Manaus, State of Amazonas

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Maria Paula Gomes Mourão

2015-06-01

Full Text Available The Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD, located in Manaus, the capital of the State of Amazonas (Western Brazilian Amazon, is a pioneering institution in this region regarding the syndromic surveillance of acute febrile illness, including arboviral infections. Based on the data from patients at the FMT-HVD, we have detected recurrent outbreaks in Manaus by the four dengue serotypes in the past 15 years, with increasing severity of the disease. This endemicity has culminated in the simultaneous circulation of all four serotypes in 2011, the first time this has been reported in Brazil. Between 1996 and 2009, 42 cases of yellow fever (YF were registered in the State of Amazonas, and 71.4% (30/42 were fatal. Since 2010, no cases have been reported. Because the introduction of the yellow fever virus into a large city such as Manaus, which is widely infested by Aedes mosquitoes, may pose a real risk of a yellow fever outbreak, efforts to maintain an appropriate immunization policy for the populace are critical. Manaus has also suffered silent outbreaks of Mayaro and Oropouche fevers lately, most of which were misdiagnosed as dengue fever. The tropical conditions of the State of Amazonas favor the existence of other arboviruses capable of producing human disease. Under this real threat, represented by at least 4 arboviruses producing human infections in Manaus and in other neighboring countries, it is important to develop an efficient public health surveillance strategy, including laboratories that are able to make proper diagnoses of arboviruses.

OUTBREAK OF ZIKA VIRUS DISEASE AND ITS COMPLICATIONS

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Gabriela S. Tsankova

2016-07-01

Full Text Available Zika virus (ZIKV is an arbovirus from Flaviviridae family, genus Flavivirus. Like most of the viruses which belong to the Flavivirus genus, it replicates in and is transmitted by mosquitoes. Unlike other arbovirus infections including dengue and chikungunya, Zika virus causes a relatively mild disease. The most common symptoms of ZIKV are mild fever, arthralgia, myalgia, headache, asthenia, abdominal pain, oedema, lymphadenopathy, retro-orbital pain, conjunctivitis, and cutaneous maculopapular rash, which last for several days to a week. Although 80% of the cases with ZIKV are asymptomatic, severe complications such as microcephalia and GBS may be observed. This explains why ZIKV is more dangerous that it was thought to be and why it rapidly evolves in unexpected challenge for the international and national public health authorities.

Serum Metabolomics Investigation of Humanized Mouse Model of Dengue Virus Infection.

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Cui, Liang; Hou, Jue; Fang, Jinling; Lee, Yie Hou; Costa, Vivian Vasconcelos; Wong, Lan Hiong; Chen, Qingfeng; Ooi, Eng Eong; Tannenbaum, Steven R; Chen, Jianzhu; Ong, Choon Nam

2017-07-15

Dengue is an acute febrile illness caused by dengue virus (DENV) and a major cause of morbidity and mortality in tropical and subtropical regions of the world. The lack of an appropriate small-animal model of dengue infection has greatly hindered the study of dengue pathogenesis and the development of therapeutics. In this study, we conducted mass spectrometry-based serum metabolic profiling from a model using humanized mice (humice) with DENV serotype 2 infection at 0, 3, 7, 14, and 28 days postinfection (dpi). Forty-eight differential metabolites were identified, including fatty acids, purines and pyrimidines, acylcarnitines, acylglycines, phospholipids, sphingolipids, amino acids and derivatives, free fatty acids, and bile acid. These metabolites showed a reversible-change trend-most were significantly perturbed at 3 or 7 dpi and returned to control levels at 14 or 28 dpi, indicating that the metabolites might serve as prognostic markers of the disease in humice. The major perturbed metabolic pathways included purine and pyrimidine metabolism, fatty acid β-oxidation, phospholipid catabolism, arachidonic acid and linoleic acid metabolism, sphingolipid metabolism, tryptophan metabolism, phenylalanine metabolism, lysine biosynthesis and degradation, and bile acid biosynthesis. Most of these disturbed pathways are similar to our previous metabolomics findings in a longitudinal cohort of adult human dengue patients across different infection stages. Our analyses revealed the commonalities of host responses to DENV infection between humice and humans and suggested that humice could be a useful small-animal model for the study of dengue pathogenesis and the development of dengue therapeutics. IMPORTANCE Dengue virus is the most widespread arbovirus, causing an estimated 390 million dengue infections worldwide every year. There is currently no effective treatment for the disease, and the lack of an appropriate small-animal model of dengue infection has greatly

AEGY-28 Cell Line of Aedes aegypti (Diptera Culicidae is Infection Refractory to Dengue 2 and Yellow Fever Virus

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Nadia Y. Castañeda

2007-07-01

Full Text Available Mosquito cell derived cultures are useful tools for arbovirus isolation, identification or characterization. For studying dengue (DENV and yellow fever viruses (YFV Aedes albopictus C6/36 or Aedes pseudoscutellaris AP-61 cell lines, are normally used. The Aedes aegypti AEGY-28 cell line was obtained from embryonic tissues and characterized previously by one of us. In order to evaluate its susceptibility to two Flavivirus, AEGY- 28 cells were inoculated with different multiplicity of infection (MOI with type 2 DENV (COL-789, MOI: 1 and 5 and YFV clinical isolates (V-341, MOI 0,02 then processed at different times post infection (p.i.. Immunostai ning and fluorometric cell-ELISA were carried out to identify and quantify viral antigens. C6/36 and Vero cells were used as positive controls. Unexpectedly, immunoreactivity was not found in inoculated AEGY-28 cells, even in higher MOI or late times p.i., therefore antigen quantification using fluorometric cell-ELISA were not  plausible. Reverse transcriptase PCR with specific primers did not detect viral RNA in AEGY-28 inoculated cells. We can conclude that Aedes aegypti AEGY-28 cell line is not susceptible to dengue and yellow fever Flavivirus, a finding possibly related with the lacking of specific molecules at the plasma membrane or absence of cell machinery necessary for viral replication.

Present and future arboviral threats.

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Weaver, Scott C; Reisen, William K

2010-02-01

Arthropod-borne viruses (arboviruses) are important causes of human disease nearly worldwide. All arboviruses circulate among wild animals, and many cause disease after spillover transmission to humans and agriculturally important domestic animals that are incidental or dead-end hosts. Viruses such as dengue (DENV) and chikungunya (CHIKV) that have lost the requirement for enzootic amplification now produce extensive epidemics in tropical urban centers. Many arboviruses recently have increased in importance as human and veterinary pathogens using a variety of mechanisms. Beginning in 1999, West Nile virus (WNV) underwent a dramatic geographic expansion into the Americas. High amplification associated with avian virulence coupled with adaptation for replication at higher temperatures in mosquito vectors, has caused the largest epidemic of arboviral encephalitis ever reported in the Americas. Japanese encephalitis virus (JEV), the most frequent arboviral cause of encephalitis worldwide, has spread throughout most of Asia and as far south as Australia from its putative origin in Indonesia and Malaysia. JEV has caused major epidemics as it invaded new areas, often enabled by rice culture and amplification in domesticated swine. Rift Valley fever virus (RVFV), another arbovirus that infects humans after amplification in domesticated animals, undergoes epizootic transmission during wet years following droughts. Warming of the Indian Ocean, linked to the El Niño-Southern Oscillation in the Pacific, leads to heavy rainfall in east Africa inundating surface pools and vertically infected mosquito eggs laid during previous seasons. Like WNV, JEV and RVFV could become epizootic and epidemic in the Americas if introduced unintentionally via commerce or intentionally for nefarious purposes. Climate warming also could facilitate the expansion of the distributions of many arboviruses, as documented for bluetongue viruses (BTV), major pathogens of ruminants. BTV, especially BTV-8

The plasma virome of febrile adult Kenyans shows frequent parvovirus B19 infections and a novel arbovirus (Kadipiro virus).

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Ngoi, Carolyne N; Siqueira, Juliana; Li, Linlin; Deng, Xutao; Mugo, Peter; Graham, Susan M; Price, Matt A; Sanders, Eduard J; Delwart, Eric

2016-12-01

Viral nucleic acids present in the plasma of 498 Kenyan adults with unexplained fever were characterized by metagenomics analysis of 51 sample pools. The highest to lowest fraction of plasma pools was positive for parvovirus B19 (75 %), pegivirus C (GBV-C) (67 %), alpha anellovirus (59 %), gamma anellovirus (55 %), beta anellovirus (41 %), dengue virus genotype 2 (DENV-2) (16 %), human immunodeficiency virus type 1 (6 %), human herpesvirus 6 (6 %), HBV (4 %), rotavirus (4 %), hepatitis B virus (4 %), rhinovirus C (2 %), Merkel cell polyomavirus (MCPyV; 2 %) and Kadipiro virus (2 %). Ranking by overall percentage of viral reads yielded similar results. Characterization of viral nucleic acids in the plasma of a febrile East African population showed a high frequency of parvovirus B19 and DENV infections and detected a reovirus (Kadipiro virus) previously reported only in Asian Culex mosquitoes, providing a baseline to compare with future virome studies to detect emerging viruses in this region.

Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus in four strains of Culex tarsalis (Diptera: Culicidae: an immunocytochemical study

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Neira Oviedo MV

2011-04-01

Full Text Available Marco V Neira Oviedo1,2, William S Romoser1, Calvin BL James1, Farida Mahmood3, William K Reisen31Tropical Disease Institute, Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH, USA; 2Oxitec Inc, Oxford, England; 3Center for Vectorborne Diseases, School of Veterinary Medicine, University of California, Davis, CA, USABackground: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV, we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion.Methods: Using immuno-stained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains – Coachella Valley, Riverside County (COAV and Kern National Wildlife Refuge (KNWR; and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP, and WEEV resistance (WR.Results and conclusions: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth

Global Emerging Infection Surveillance and Response (GEIS)- Avian Influenza Pandemic Influenza (AI/PI) Program

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2014-10-01

KEMRI operated reference laboratories for this work in Nairobi, Kericho, and Kisumu, including the arbovirus reference laboratory, the antimalarial ...in military and civilian populations, and monitor the pattern of antimalarial resistance across Kenya. 15. SUBJECT TERMS NOTHING LISTED 16...confirms our earlier assertion that as we progress away from the H1N1 pandemic, we have noticed a decline in influenza activity suggesting that the high

Inactivation of dengue, chikungunya, and Ross River viruses in platelet concentrates after treatment with ultraviolet C light.

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Faddy, Helen M; Fryk, Jesse J; Prow, Natalie A; Watterson, Daniel; Young, Paul R; Hall, Roy A; Tolksdorf, Frank; Sumian, Chryslain; Gravemann, Ute; Seltsam, Axel; Marks, Denese C

2016-06-01

Arboviruses, including dengue (DENV 1-4), chikungunya (CHIKV), and Ross River (RRV), are emerging viruses that are a risk for transfusion safety globally. An approach for managing this risk is pathogen inactivation, such as the THERAFLEX UV-Platelets system. We investigated the ability of this system to inactivate the above mentioned arboviruses. DENV 1-4, CHIKV, or RRV were spiked into buffy coat (BC)-derived platelet (PLT) concentrates in additive solution and treated with the THERAFLEX UV-Platelets system at the following doses: 0.05, 0.1, 0.15, and 0.2 J/cm(2) (standard dose). Pre- and posttreatment samples were taken for each dose, and the level of viral infectivity was determined. At the standard ultraviolet C (UVC) dose (0.2 J/cm(2) ), viral inactivation of at least 4.43, 6.34, and 5.13 log or more, was observed for DENV 1-4, CHIKV, and RRV, respectively. A dose dependency in viral inactivation was observed with increasing UVC doses. Our study has shown that DENV, CHIKV, and RRV, spiked into BC-derived PLT concentrates, were inactivated by the THERAFLEX UV-Platelets system to the limit of detection of our assay, suggesting that this system could contribute to the safety of PLT concentrates with respect to these emerging arboviruses. © 2016 AABB.

Wolbachia-induced aae-miR-12 miRNA negatively regulates the expression of MCT1 and MCM6 genes in Wolbachia-infected mosquito cell line.

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Solomon Osei-Amo

Full Text Available BACKGROUND: Best recognized for its role in manipulating host reproduction, the parasitic gram-negative Wolbachia pipientis is known to colonize a wide range of invertebrates. The endosymbiotic bacterium has recently been shown to cause a life-shortening effect as well as inhibiting replication of arboviruses in Aedes aegypti; although the molecular mechanisms behind these effects are largely unknown. MicroRNAs (miRNAs have been determined to have a wide range of roles in regulating gene expression in eukaryotes. A recent study showed that several A. aegypti mosquito miRNAs are differentially expressed when infected with Wolbachia. METHODOLOGY/PRINCIPAL FINDINGS: Based on the prior knowledge that one of these miRNAs, aae-miR-12, is differentially expressed in mosquitoes infected with Wolbachia, we aimed to determine any significance of this mediation. We also set out to characterize the target genes of this miRNA in the A. aegpyti genome. Bioinformatic approaches predicted a list of potential target genes and subsequent functional analyses confirmed that two of these, DNA replication licensing (MCM6 and monocarboxylate transporter (MCT1, are under the regulative control of aae-miR-12. We also demonstrated that aae-miR-12 is critical in the persistence of Wolbachia in the host cell. CONCLUSIONS/SIGNIFICANCE: Our study has identified two target genes of aae-miR-12, a differentially expressed mosquito miRNA in Wolbachia-infected cells, and determined that the miRNA affects Wolbachia density in the host cells.

Exploring of primate models of tick-borne flaviviruses infection for evaluation of vaccines and drugs efficacy.

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Natalia S Pripuzova

Full Text Available Tick-borne encephalitis virus (TBEV is one of the most prevalent and medically important tick-borne arboviruses in Eurasia. There are overlapping foci of two flaviviruses: TBEV and Omsk hemorrhagic fever virus (OHFV in Russia. Inactivated vaccines exist only against TBE. There are no antiviral drugs for treatment of both diseases. Optimal animal models are necessary to study efficacy of novel vaccines and treatment preparations against TBE and relative flaviviruses. The models for TBE and OHF using subcutaneous inoculation were tested in Cercopithecus aethiops and Macaca fascicularis monkeys with or without prior immunization with inactivated TBE vaccine. No visible clinical signs or severe pathomorphological lesions were observed in any monkey infected with TBEV or OHFV. C. aethiops challenged with OHFV showed massive hemolytic syndrome and thrombocytopenia. Infectious virus or viral RNA was revealed in visceral organs and CNS of C. aethiops infected with both viruses; however, viremia was low. Inactivated TBE vaccines induced high antibody titers against both viruses and expressed booster after challenge. The protective efficacy against TBE was shown by the absence of virus in spleen, lymph nodes and CNS of immunized animals after challenge. Despite the absence of expressed hemolytic syndrome in immunized C. aethiops TBE vaccine did not prevent the reproduction of OHFV in CNS and visceral organs. Subcutaneous inoculation of M. fascicularis with two TBEV strains led to a febrile disease with well expressed viremia, fever, and virus reproduction in spleen, lymph nodes and CNS. The optimal terms for estimation of the viral titers in CNS were defined as 8-16 days post infection. We characterized two animal models similar to humans in their susceptibility to tick-borne flaviviruses and found the most optimal scheme for evaluation of efficacy of preventive and therapeutic preparations. We also identified M. fascicularis to be more susceptible to

Zika Virus: Critical Information for Emergency Providers.

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Shastry, Siri; Koenig, Kristi L; Hirshon, Jon Mark

2016-08-01

Zika virus is an arbovirus of the Flaviviridae family. It is primarily a minimally symptomatic mosquito-borne infection. However, with Zika's 2015 to 2016 introduction into the Western Hemisphere and its dramatic and rapid spread, it has become a public health concern, in large part due to congenital abnormalities associated with infection in pregnant women. In early 2016, the World Health Organization declared the microcephaly and other neurologic conditions associated with Zika virus infection a public health emergency of international concern. This article discusses the current epidemiologic and clinical understanding of Zika virus, focusing on critical information needed by emergency providers. Copyright © 2016 Elsevier Inc. All rights reserved.

Current status, challenges and perspectives in the development of vaccines against yellow fever, dengue, Zika and chikungunya viruses.

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Silva, José V J; Lopes, Thaísa R R; Oliveira-Filho, Edmilson F de; Oliveira, Renato A S; Durães-Carvalho, Ricardo; Gil, Laura H V G

2018-06-01

Emerging and re-emerging viral infections transmitted by insect vectors (arthopode-borne viruses, arbovirus) are a serious threat to global public health. Among them, yellow fever (YFV), dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses are particularly important in tropical and subtropical regions. Although vector control is one of the most used prophylactic measures against arboviruses, it often faces obstacles, such as vector diversity, uncontrolled urbanization and increasing resistance to insecticides. In this context, vaccines may be the best control strategy for arboviral diseases. Here, we provide a general overview about licensed vaccines and the most advanced vaccine candidates against YFV, DENV, CHIKV and ZIKV. In particular, we highlight vaccine difficulties, the current status of the most advanced strategies and discuss how the molecular characteristics of each virus can influence the choice of the different vaccine formulations. Copyright © 2018 Elsevier B.V. All rights reserved.

Reptiles and Amphibians as Potential Reservoir Hosts of Chikungunya Virus.

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Bosco-Lauth, Angela M; Hartwig, Airn E; Bowen, Richard A

2018-03-01

Chikungunya virus is an emerging arbovirus of significant human-health concern. Little is known about its sylvatic cycle, including whether ectothermic vertebrates are permissive to infection. In this study, individuals from ten species of reptiles and amphibians were inoculated with chikungunya virus and samples of blood were tested to characterize viremia and seroconversion. Viremia was not detected in cane toads, house geckos, or American alligators, but most of the green iguanas, red-eared sliders, ball and Burmese pythons, leopard frogs, Texas toads, and garter snakes developed viremia. Peak virus titers in serum of up to 4.5, 4.7, and 5.1 log 10 plaque-forming units per milliliter were observed for garter snakes, ball pythons, and Texas toads, respectively. These results add to those of other studies that have suggested a possible role for ectothermic vertebrates in the ecology of arbovirus maintenance and transmission in nature.

Uso de células de Aedes albopictus C6/36 na propagação e classificação de arbovírus das famílias Togaviridae, Flaviviridae, Bunyaviridae e Rhabdoviridae

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Luiz Tadeu Moraes Figueiredo

1990-03-01

Full Text Available Colônias de células de mosquito Aedes albopictus C6/36 foram infectadas com 23 arbovirus, sendo 19 destes existentes no Brasil, pertencentes às famílias Togaviridae, Flaviviridae, Bunyaviridae e Rhabdoviridae. A Replicação virai foi detectada por imunofluorescência indireta com todos os vírus estudados enquanto que o efeito citopático foi observado durante a infecção por alguns destes. No teste de imunofluorescência indireta utilizou-se fluidos ascíticos imunes de camundongos, específicos para os vírus estudados. A replicação virai caracterizada por grande produção de antígeno recomenda a utilização de células C6/36 na propagação e em tentativas de isolamento desses arbovirus. A técnica de imunofluorescência ofereceu importantes subsídios na classificação e identificação de vírus que replicam nestas células.C6/36 Aedes albopictus cells were infected w ith Brazilian arbovirus from the families Togaviridae, Flaviviridae, Bunyaviridae and Rhabdoviridae. Replication was obtained with all the studied viruses and cytopathic effect was observed with some. Viral antigen was assayed in C6/36 cell cultures for antigen was assayed in C6/36 cells by an indirect immunofluorescence test using specific mouse immune ascitic fluid. Antigen production was detected in C6/36 cells infected with all the studied viruses. The author recommends the inoculation of C6/36 cell cultures for isolation of virus from the four studied families. The immunofluorescence technique is an important tool for classification and identification of virus growing in C6/36 cells.

Dynamic remodeling of lipids coincides with dengue virus replication in the midgut of Aedes aegypti mosquitoes.

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Nunya Chotiwan

2018-02-01

Full Text Available We describe the first comprehensive analysis of the midgut metabolome of Aedes aegypti, the primary mosquito vector for arboviruses such as dengue, Zika, chikungunya and yellow fever viruses. Transmission of these viruses depends on their ability to infect, replicate and disseminate from several tissues in the mosquito vector. The metabolic environments within these tissues play crucial roles in these processes. Since these viruses are enveloped, viral replication, assembly and release occur on cellular membranes primed through the manipulation of host metabolism. Interference with this virus infection-induced metabolic environment is detrimental to viral replication in human and mosquito cell culture models. Here we present the first insight into the metabolic environment induced during arbovirus replication in Aedes aegypti. Using high-resolution mass spectrometry, we have analyzed the temporal metabolic perturbations that occur following dengue virus infection of the midgut tissue. This is the primary site of infection and replication, preceding systemic viral dissemination and transmission. We identified metabolites that exhibited a dynamic-profile across early-, mid- and late-infection time points. We observed a marked increase in the lipid content. An increase in glycerophospholipids, sphingolipids and fatty acyls was coincident with the kinetics of viral replication. Elevation of glycerolipid levels suggested a diversion of resources during infection from energy storage to synthetic pathways. Elevated levels of acyl-carnitines were observed, signaling disruptions in mitochondrial function and possible diversion of energy production. A central hub in the sphingolipid pathway that influenced dihydroceramide to ceramide ratios was identified as critical for the virus life cycle. This study also resulted in the first reconstruction of the sphingolipid pathway in Aedes aegypti. Given conservation in the replication mechanisms of several

Dynamic remodeling of lipids coincides with dengue virus replication in the midgut of Aedes aegypti mosquitoes.

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Chotiwan, Nunya; Andre, Barbara G; Sanchez-Vargas, Irma; Islam, M Nurul; Grabowski, Jeffrey M; Hopf-Jannasch, Amber; Gough, Erik; Nakayasu, Ernesto; Blair, Carol D; Belisle, John T; Hill, Catherine A; Kuhn, Richard J; Perera, Rushika

2018-02-01

We describe the first comprehensive analysis of the midgut metabolome of Aedes aegypti, the primary mosquito vector for arboviruses such as dengue, Zika, chikungunya and yellow fever viruses. Transmission of these viruses depends on their ability to infect, replicate and disseminate from several tissues in the mosquito vector. The metabolic environments within these tissues play crucial roles in these processes. Since these viruses are enveloped, viral replication, assembly and release occur on cellular membranes primed through the manipulation of host metabolism. Interference with this virus infection-induced metabolic environment is detrimental to viral replication in human and mosquito cell culture models. Here we present the first insight into the metabolic environment induced during arbovirus replication in Aedes aegypti. Using high-resolution mass spectrometry, we have analyzed the temporal metabolic perturbations that occur following dengue virus infection of the midgut tissue. This is the primary site of infection and replication, preceding systemic viral dissemination and transmission. We identified metabolites that exhibited a dynamic-profile across early-, mid- and late-infection time points. We observed a marked increase in the lipid content. An increase in glycerophospholipids, sphingolipids and fatty acyls was coincident with the kinetics of viral replication. Elevation of glycerolipid levels suggested a diversion of resources during infection from energy storage to synthetic pathways. Elevated levels of acyl-carnitines were observed, signaling disruptions in mitochondrial function and possible diversion of energy production. A central hub in the sphingolipid pathway that influenced dihydroceramide to ceramide ratios was identified as critical for the virus life cycle. This study also resulted in the first reconstruction of the sphingolipid pathway in Aedes aegypti. Given conservation in the replication mechanisms of several flaviviruses transmitted

piRNA Profiling of Dengue Virus Type 2-Infected Asian Tiger Mosquito and Midgut Tissues

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Yanhai Wang

2018-04-01

Full Text Available The Asian tiger mosquito, Aedes albopictus, is a competent vector for the majority of arboviruses. The mosquito innate immune response is a primary determinant for arthropod-borne virus transmission, and the midgut is the first barrier to pathogen transmission. Mosquito antiviral immunity is primarily mediated by the small interfering RNA pathway. However, the roles that the P-element induced wimpy testis (PIWI-interacting RNA (piRNA pathway play in antiviral immunity in Ae. albopictus and its midgut still need further exploration. This study aimed to explore the profiles of both viral-derived and host-originated piRNAs in the whole body and midgut infected with Dengue virus 2 (DENV-2 in Ae. albopictus, and to elucidate gene expression profile differences of the PIWI protein family between adult females and their midguts. A deep sequencing-based method was used to identify and analyze small non-coding RNAs, especially the piRNA profiles in DENV-2-infected Ae. albopictus and its midgut. The top-ranked, differentially-expressed piRNAs were further validated using Stem-loop qRT-PCR. Bioinformatics analyses and reverse-transcription PCR (RT-PCR methods were used to detect PIWI protein family members, and their expression profiles. DENV-2 derived piRNAs (vpiRNA, 24–30 nts were observed in both infected Ae. albopictus and its midgut; however, only vpiRNA in the whole-body library had a weak preference for adenine at position 10 (10A in the sense molecules as a feature of secondary piRNA. These vpiRNAs were not equally distributed, instead they were derived from a few specific regions of the genome, especially several hot spots, and displayed an obvious positive strand bias. We refer to the differentially expressed host piRNAs after DENV infection as virus-induced host endogenous piRNAs (vepiRNAs. However, we found that vepiRNAs were abundant in mosquito whole-body tissue, but deficient in the midgut. A total of eleven PIWI family genes were

Rift Valley fever virus-infected mosquito ova and associated pathology: possible implications for endemic maintenance

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Romoser WS

2011-09-01

hemocoel, RVFV-infected reproductive tissues were found, particularly follicular epithelia and oocyte/nurse cells. Ovarian infection from the hemocoel is a crucial step in establishing a vertically transmitting mosquito line. Ovarian follicles originate from germarial cells, primordia located distally in each ovariole, and infection of these cells is expected to be requisite for long-term vertical transmission. However, no germarial cell infection was found, so establishing a new line of vertically transmitting mosquitoes may require two generations. The findings support the hypothesis that Ae. mcintoshi is involved in the endemic maintenance of RVFV by vertical transmission. Detection of distinct pathology in infected eggs raises the possibility of virus-laden eggs being deposited among healthy eggs, thereby providing an exogenous source of infection via ingestion by mosquito larvae and other organisms. This has potentially significant epidemiological implications. Possible modes of entry of virus from the hemocoel into the ovaries and routes by which larvae might become infected by ingesting virus are discussed.Keywords: hemocoel, ovary, vertical transmission, Aedes mcintoshi, arbovirus, antigen positive

A Role for RNA Viruses in the Pathogenesis of Burkitt's Lymphoma: The Need for Reappraisal

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Corry van den Bosch

2012-01-01

Full Text Available Certain infectious agents are associated with lymphomas, but the strength of the association varies geographically, suggesting that local environmental factors make important contributions to lymphomagenesis. Endemic Burkitt’s Lymphoma has well-defined environmental requirements making it particularly suitable for research into local environmental factors. The Epstein-Barr virus and holoendemic Malaria are recognized as important cofactors in endemic Burkitt’s Lymphoma and their contributions are discussed. Additionally, infection with Chikungunya Fever, a potentially oncogenic arbovirus, was associated with the onset of endemic Burkitt’s Lymphoma in one study and also with space-time case clusters of the lymphoma. Chikungunya Virus has several characteristics typical of oncogenic viruses. The Flavivirus, Hepatitis C, a Class 1 Human Carcinogen, closely related to the arboviruses, Yellow Fever, and Dengue, is also more distantly related to Chikungunya Virus. The mechanisms of oncogenesis believed to operate in Hepatitis C lymphomagenesis are discussed, as is their potential applicability to Chikungunya Virus.

Diseases Transmitted by Birds.

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Levison, Matthew E

2015-08-01

Although many people these days actually work very hard at leisure time activities, diseases are most commonly acquired from birds during the course of work in the usual sense of the term, not leisure. However, travel for pleasure to areas where the diseases are highly endemic puts people at risk of acquiring some of these bird-related diseases (for example, histoplasmosis and arbovirus infections), as does ownership of birds as pets (psittacosis).

[Characteristics of clinical features of tick-borne encephalitis in Crimea].

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Borisova, M A; Markeshin, S Ia; Riazanova, N Ia; Degtiareva, A A; Zakharova, T F; Bychkova, M V

1989-12-01

The analysis of data collected from the clinical epidemiological and virological surveys in 1985-1988 on the incidence of arbovirus infection in population provided evidence for circulation of tick-borne encephalitis (TBE) virus in the Crimea. Etiological relevance of TBE virus in the onset of the diseases was revealed. Clinical picture of TBE in the Crimea is characterized by severe forms and diphasic fever with the relapse running more grave and protracted course.

Wolbachia Blocks Currently Circulating Zika Virus Isolates in Brazilian Aedes aegypti Mosquitoes

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Dutra, Heverton Leandro Carneiro; Rocha, Marcele Neves; Dias, Fernando Braga Stehling; Mansur, Simone Brutman; Caragata, Eric Pearce; Moreira, Luciano Andrade

2016-01-01

Summary The recent association of Zika virus with cases of microcephaly has sparked a global health crisis and highlighted the need for mechanisms to combat the Zika vector, Aedes aegypti mosquitoes. Wolbachia pipientis, a bacterial endosymbiont of insect, has recently garnered attention as a mechanism for arbovirus control. Here we report that Aedes aegypti harboring Wolbachia are highly resistant to infection with two currently circulating Zika virus isolates from the recent Brazilian epide...

First report in italy of the exotic mosquito species Aedes (Finlaya koreicus, a potential vector of arboviruses and filariae

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Capelli Gioia

2011-09-01

Full Text Available Abstract Background In the Veneto region (north-eastern Italy an entomological surveillance system has been implemented since the introduction of the Asian tiger mosquito (Aedes albopictus in 1991. During the routine monitoring activity in a tiger mosquito-free area, an unexpected mosquito was noticed, which clearly did not belong to the recorded Italian fauna. Findings At the end of May 2011, twelve larvae and pupae were collected in a small village in Belluno province (Veneto region from a single manhole. Ten adults reared in the laboratory were morphologically and genetically identified as Aedes (Finlaya koreicus (Edwards, 1917, a species native to Southeast Asia. The subsequent investigations carried out in the following months in the same village provided evidence that this species had become established locally. Entomological and epidemiological investigations are currently ongoing in the surrounding area, to verify the eventual extension of the species outside the village and to trace back the route of entry into Italy. Conclusions This is the first report in Italy of the introduction of the exotic mosquito Ae. koreicus. This species has been shown experimentally to be competent in the transmission of the Japanese encephalitis virus and of the dog heartworm Dirofilaria immitis and is considered a potential vector of other arboviruses. Thus, the establishment of this species may increase the current risk or pose new potential threats, for human and animal health. This finding considerably complicates the entomological monitoring of the Asian tiger mosquito Ae. albopictus in Italy and stresses the importance of implementing the entomological surveillance for the early detection of and the rapid response against invasive mosquito species.

Arbovirus Detection in Insect Vectors by Rapid, High-Throughput Pyrosequencing

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2010-11-09

This may likely indicate that all of the Ae. aegypti mosquitoes used in this study were infected or colonized with Asaia sp ., regardless of their DENV...large contigs that by BLAST had their best hit to a rRNA of various fungal origins (including the genera Penicillium and Aspergillus) and in all five...Asaia. While bacteria in the genus Asaia have been previously reported to colonize Anopheles sp . mosquitoes [24], to our knowledge, they have not

C6/36 Aedes albopictus cells have a dysfunctional antiviral RNA interference response.

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Doug E Brackney

2010-10-01

Full Text Available Mosquitoes rely on RNA interference (RNAi as their primary defense against viral infections. To this end, the combination of RNAi and invertebrate cell culture systems has become an invaluable tool in studying virus-vector interactions. Nevertheless, a recent study failed to detect an active RNAi response to West Nile virus (WNV infection in C6/36 (Aedes albopictus cells, a mosquito cell line frequently used to study arthropod-borne viruses (arboviruses. Therefore, we sought to determine if WNV actively evades the host's RNAi response or if C6/36 cells have a dysfunctional RNAi pathway. C6/36 and Drosophila melanogaster S2 cells were infected with WNV (Flaviviridae, Sindbis virus (SINV, Togaviridae and La Crosse virus (LACV, Bunyaviridae and total RNA recovered from cell lysates. Small RNA (sRNA libraries were constructed and subjected to high-throughput sequencing. In S2 cells, virus-derived small interfering RNAs (viRNAs from all three viruses were predominantly 21 nt in length, a hallmark of the RNAi pathway. However, in C6/36 cells, viRNAs were primarily 17 nt in length from WNV infected cells and 26-27 nt in length in SINV and LACV infected cells. Furthermore, the origin (positive or negative viral strand and distribution (position along viral genome of S2 cell generated viRNA populations was consistent with previously published studies, but the profile of sRNAs isolated from C6/36 cells was altered. In total, these results suggest that C6/36 cells lack a functional antiviral RNAi response. These findings are analogous to the type-I interferon deficiency described in Vero (African green monkey kidney cells and suggest that C6/36 cells may fail to accurately model mosquito-arbovirus interactions at the molecular level.

Dengue-1 virus and vector competence of Aedes aegypti (Diptera: Culicidae) populations from New Caledonia.

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Calvez, Elodie; Guillaumot, Laurent; Girault, Dominique; Richard, Vaea; O'Connor, Olivia; Paoaafaite, Tuterarii; Teurlai, Magali; Pocquet, Nicolas; Cao-Lormeau, Van-Mai; Dupont-Rouzeyrol, Myrielle

2017-08-09

Dengue virus (DENV) is the arbovirus with the highest incidence in New Caledonia and in the South Pacific region. In 2012-2014, a major DENV-1 outbreak occurred in New Caledonia. The only known vector of DENV in New Caledonia is Aedes aegypti but no study has yet evaluated the competence of New Caledonia Ae. aegypti populations to transmit DENV. This study compared the ability of field-collected Ae. aegypti from different locations in New Caledonia to transmit the DENV-1 responsible for the 2012-2014 outbreak. This study also aimed to compare the New Caledonia results with the vector competence of Ae. aegypti from French Polynesia as these two French countries have close links, including arbovirus circulation. Three wild Ae. aegypti populations were collected in New Caledonia and one in French Polynesia. Female mosquitoes were orally exposed to DENV-1 (10 6 FFU/ml). Mosquito bodies (thorax and abdomen), heads and saliva were analyzed to measure infection, dissemination, transmission rates and transmission efficiency, at 7, 14 and 21 days post-infection (dpi), respectively. DENV-1 infection rates were heterogeneous, but dissemination rates were high and homogenous among the three Ae. aegypti populations from New Caledonia. Despite this high DENV-1 dissemination rate, the transmission rate, and therefore the transmission efficiency, observed were low. Aedes aegypti population from New Caledonia was less susceptible to infection and had lower ability to transmit DENV-1 than Ae. aegypti populations from French Polynesia. This study suggests that even if susceptible to infection, the New Caledonian Ae. aegypti populations were moderately competent vectors for DENV-1 strain from the 2012-2014 outbreak. These results strongly suggest that other factors might have contributed to the spread of this DENV-1 strain in New Caledonia and in the Pacific region.

Cooler temperatures destabilize RNA interference and increase susceptibility of disease vector mosquitoes to viral infection.

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Zach N Adelman

Full Text Available The impact of global climate change on the transmission dynamics of infectious diseases is the subject of extensive debate. The transmission of mosquito-borne viral diseases is particularly complex, with climatic variables directly affecting many parameters associated with the prevalence of disease vectors. While evidence shows that warmer temperatures often decrease the extrinsic incubation period of an arthropod-borne virus (arbovirus, exposure to cooler temperatures often predisposes disease vector mosquitoes to higher infection rates. RNA interference (RNAi pathways are essential to antiviral immunity in the mosquito; however, few experiments have explored the effects of temperature on the RNAi machinery.We utilized transgenic "sensor" strains of Aedes aegypti to examine the role of temperature on RNA silencing. These "sensor" strains express EGFP only when RNAi is inhibited; for example, after knockdown of the effector proteins Dicer-2 (DCR-2 or Argonaute-2 (AGO-2. We observed an increase in EGFP expression in transgenic sensor mosquitoes reared at 18°C as compared with 28°C. Changes in expression were dependent on the presence of an inverted repeat with homology to a portion of the EGFP sequence, as transgenic strains lacking this sequence, the double stranded RNA (dsRNA trigger for RNAi, showed no change in EGFP expression when reared at 18°C. Sequencing small RNAs in sensor mosquitoes reared at low temperature revealed normal processing of dsRNA substrates, suggesting the observed deficiency in RNAi occurs downstream of DCR-2. Rearing at cooler temperatures also predisposed mosquitoes to higher levels of infection with both chikungunya and yellow fever viruses.This data suggest that microclimates, such as those present in mosquito breeding sites, as well as more general climactic variables may influence the dynamics of mosquito-borne viral diseases by affecting the antiviral immunity of disease vectors.

Aedes albopictus (Skuse, 1894) infected with the American-Asian genotype of dengue type 2 virus in Medellín suggests its possible role as vector of dengue fever in Colombia.

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Gómez-Palacio, Andrés; Suaza-Vasco, Juan; Castaño, Sandra; Triana, Omar; Uribe, Sandra

2017-03-29

Aedes aegypti and Ae. albopictus are recognized vectors of dengue, yellow fever, chikungunya and Zika arboviruses in several countries worldwide. In Colombia, Ae. albopictus geographical distribution has increased to include highly populated cities such as Cali and Medellín. Although this species has been frequently found in urban and semi-urban zones in the country, its role as vector of the dengue fever is poorly known. To identify the presence of Ae. albopictus specimens naturally infected with dengue virus collected in Medellín. Insects were collected in the Universidad Nacional de Colombia campus in Medellín. Individuals were classified as Ae. albopictus and confirmed by DNA barcode region analysis. Mosquitoes were processed for dengue virus identification, and a fragment of the NS3 gen was sequenced and compared with DENV-2 genotypes reported in the literature. Sequence analysis of COI indicated Ae. albopictus individuals were similar to those recently reported in Colombia, and genetically close to those from other regions worldwide. Among the pools tested one was positive for DENV-2, and the NS3 analysis indicated it belonged to the Asian-American clade. We report the presence Ae. albopictus naturally infected with the Asian-American genotype of DENV-2 in Colombia. The presence of Ae. albopictus specimens carrying the most common genotype infecting humans in a highly populated city such as Medellín indicates its potential role as dengue vector in Colombia and highlights the relevance of including it in current vector surveillance strategies.

Zika virus transmission to mouse ear by mosquito bite: a laboratory model that replicates the natural transmission process.

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Secundino, Nagila Francinete Costa; Chaves, Barbara Aparecida; Orfano, Alessandra Silva; Silveira, Karine Renata Dias; Rodrigues, Nilton Barnabe; Campolina, Thais Bonifácio; Nacif-Pimenta, Rafael; Villegas, Luiz Eduardo Martinez; Silva, Breno Melo; Lacerda, Marcus Vinícius Guimarães; Norris, Douglas Eric; Pimenta, Paulo Filemon Paolucci

2017-07-20

Zika disease has transformed into a serious global health problem due to the rapid spread of the arbovirus and alarming severity including congenital complications, microcephaly and Guillain-Barré syndrome. Zika virus (ZIKV) is primarily transmitted to humans through the bite of an infective mosquito, with Aedes aegypti being the main vector. We successfully developed a ZIKV experimental transmission model by single infectious Ae. aegypti bite to a laboratory mouse using circulating Brazilian strains of both arbovirus and vector. Mosquitoes were orally infected and single Ae. aegypti were allowed to feed on mouse ears 14 days post-infection. Additionally, salivary gland (SG) homogenates from infected mosquitoes were intrathoracically inoculated into naïve Ae. aegypti. Mosquito and mouse tissue samples were cultured in C6/36 cells and processed by quantitative real-time PCR. A total of 26 Ae. aegypti were allowed to feed individually on mouse ears. Of these, 17 mosquitoes fed, all to full engorgement. The transmission rate of ZIKV by bite from these engorged mosquitoes to mouse ears was 100%. The amount of virus inoculated into the ears by bites ranged from 2 × 10 2 -2.1 × 10 10 ZIKV cDNA copies and was positively correlated with ZIKV cDNA quantified from SGs dissected from mosquitoes post-feeding. Replicating ZIKV was confirmed in macerated SGs (2.45 × 10 7 cDNA copies), mouse ear tissue (1.15 × 10 3 cDNA copies, and mosquitoes 14 days post-intrathoracic inoculation (1.49 × 10 7 cDNA copies) by cytopathic effect in C6/36 cell culture and qPCR. Our model illustrates successful transmission of ZIKV by an infectious mosquito bite to a live vertebrate host. This approach offers a comprehensive tool for evaluating the development of infection in and transmission from mosquitoes, and the vertebrate-ZIKV interaction and progression of infection following a natural transmission process.

In vitro comparison of three common essential oils mosquito repellents as inhibitors of the Ross River virus

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Ralambondrainy, Miora; Belarbi, Essia; Viranaicken, Wildriss; Baranauskienė, Renata; Venskutonis, Petras Rimantas; Desprès, Philippe; El Kalamouni, Chaker; Sélambarom, Jimmy

2018-01-01

Background The essential oils of Cymbopogon citratus (CC), Pelargonium graveolens (PG) and Vetiveria zizanioides (VZ) are commonly used topically to prevent mosquito bites and thus the risk of infection by their vectored pathogens such as arboviruses. However, since mosquito bites are not fully prevented, the effect of these products on the level of viral infection remains unknown. Objectives To evaluate in vitro the essentials oils from Reunion Island against one archetypal arbovirus, the Ross River virus (RRV), and investigate the viral cycle step that was impaired by these oils. Methods The essential oils were extracted by hydrodistillation and analyzed by a combination of GC-FID and GC×GC-TOF MS techniques. In vitro studies were performed on HEK293T cells to determine their cytotoxicity, their cytoprotective and virucidal capacities on RRV-T48 strain, and the level of their inhibitory effect on the viral replication and residual infectivity prior, during or following viral adsorption using the reporter virus RRV-renLuc. Results Each essential oil was characterized by an accurate quantification of their terpenoid content. PG yielded the least-toxic extract (CC50 > 1000 μg.mL-1). For the RRV-T48 strain, the monoterpene-rich CC and PG essential oils reduced the cytopathic effect but did not display virucidal activity. The time-of-addition assay using the gene reporter RRV-renLuc showed that the CC and PG essential oils significantly reduced viral replication and infectivity when applied prior, during and early after viral adsorption. Overall, no significant effect was observed for the low monoterpene-containing VZ essential oil. Conclusion The inhibitory profiles of the three essential oils suggest the high value of the monoterpene-rich essential oils from CC and PG against RRV infection. Combined with their repellent activity, the antiviral activity of the essential oils of CC and PG may provide a new option to control arboviral infection. PMID:29771946

Rift Valley fever virus: strategies for maintenance, survival and vertical transmission in mosquitoes.

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Lumley, Sarah; Horton, Daniel L; Hernandez-Triana, Luis L M; Johnson, Nicholas; Fooks, Anthony R; Hewson, Roger

2017-05-01

Rift Valley fever virus (RVFV) is a mosquito-borne arbovirus causing severe disease in humans and ruminants. Spread of RVFV out of Africa has raised concerns that it could emerge in Europe or the USA. Virus persistence is dependent on successful infection of, replication in, and transmission to susceptible vertebrate and invertebrate hosts, modulated by virus-host and vector-virus interactions. The principal accepted theory for the long-term maintenance of RVFV involves vertical transmission (VT) of virus to mosquito progeny, with the virus surviving long inter-epizootic periods within the egg. This VT hypothesis, however, is yet to be comprehensively proven. Here, evidence for and against the VT of RVFV is reviewed along with the identification of factors limiting its detection in natural and experimental data. The observations of VT for other arboviruses in the genera Alphavirus, Flavivirus and Orthobunyavirus are discussed within the context of RVFV. The review concludes that VT of RVFV is likely but that current data are insufficient to irrefutably prove this hypothesis.

Climate Variability, Social and Environmental Factors, and Ross River Virus Transmission: Research Development and Future Research Needs

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Tong, Shilu; Dale, Pat; Nicholls, Neville; Mackenzie, John S.; Wolff, Rodney; McMichael, Anthony J.

2008-01-01

Background Arbovirus diseases have emerged as a global public health concern. However, the impact of climatic, social, and environmental variability on the transmission of arbovirus diseases remains to be determined. Objective Our goal for this study was to provide an overview of research development and future research directions about the interrelationship between climate variability, social and environmental factors, and the transmission of Ross River virus (RRV), the most common and widespread arbovirus disease in Australia. Methods We conducted a systematic literature search on climatic, social, and environmental factors and RRV disease. Potentially relevant studies were identified from a series of electronic searches. Results The body of evidence revealed that the transmission cycles of RRV disease appear to be sensitive to climate and tidal variability. Rainfall, temperature, and high tides were among major determinants of the transmission of RRV disease at the macro level. However, the nature and magnitude of the interrelationship between climate variability, mosquito density, and the transmission of RRV disease varied with geographic area and socioenvironmental condition. Projected anthropogenic global climatic change may result in an increase in RRV infections, and the key determinants of RRV transmission we have identified here may be useful in the development of an early warning system. Conclusions The analysis indicates that there is a complex relationship between climate variability, social and environmental factors, and RRV transmission. Different strategies may be needed for the control and prevention of RRV disease at different levels. These research findings could be used as an additional tool to support decision making in disease control/surveillance and risk management. PMID:19079707

MicroRNA and cellular targets profiling reveal miR-217 and miR-576-3p as proviral factors during Oropouche infection.

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Victor Emmanuel Viana Geddes

2018-05-01

Full Text Available Oropouche Virus is the etiological agent of an arbovirus febrile disease that affects thousands of people and is widespread throughout Central and South American countries. Although isolated in 1950's, still there is scarce information regarding the virus biology and its prevalence is likely underestimated. In order to identify and elucidate interactions with host cells factors and increase the understanding about the Oropouche Virus biology, we performed microRNA (miRNA and target genes screening in human hepatocarcinoma cell line HuH-7. Cellular miRNAs are short non-coding RNAs that regulates gene expression post-transcriptionally and play key roles in several steps of viral infections. The large scale RT-qPCR based screening found 13 differentially expressed miRNAs in Oropouche infected cells. Further validation confirmed that miR-217 and miR-576-3p were 5.5 fold up-regulated at early stages of virus infection (6 hours post-infection. Using bioinformatics and pathway enrichment analysis, we predicted the cellular targets genes for miR-217 and miR-576-3p. Differential expression analysis of RNA from 95 selected targets revealed genes involved in innate immunity modulation, viral release and neurological disorder outcomes. Further analysis revealed the gene of decapping protein 2 (DCP2, a previous known restriction factor for bunyaviruses transcription, as a miR-217 candidate target that is progressively down-regulated during Oropouche infection. Our analysis also showed that activators genes involved in innate immune response through IFN-β pathway, as STING (Stimulator of Interferon Genes and TRAF3 (TNF-Receptor Associated Factor 3, were down-regulated as the infection progress. Inhibition of miR-217 or miR-576-3p restricts OROV replication, decreasing viral RNA (up to 8.3 fold and virus titer (3 fold. Finally, we showed that virus escape IFN-β mediated immune response increasing the levels of cellular miR-576-3p resulting in a decreasing of

Mayaro virus: imported cases of human infection in São Paulo State, Brazil Vírus Mayaro: casos importados de infecção humana no Estado de São Paulo, Brasil

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Terezinha Lisieux M. Coimbra

2007-08-01

Full Text Available Mayaro virus (MAYV is an arbovirus (Togaviridae: Alphavirus enzootic in tropical South America and maintained in a sylvan cycle involving wild vertebrates and Haemagogus mosquitoes. MAYV cases occur sporadically in persons with a history of recent activities inside or around forests. This paper reports three cases of MAYV fever detected in men infected in Camapuã, MS, Brazil. Serum samples collected at four days and two months after the onset of the symptoms and examined by hemagglutination inhibition test, revealed monotypic seroconversion to MAYV. Isolation of the virus was obtained from one of the samples by inoculation of the first blood samples into newborn mice. A suspension of the infected mouse brain was inoculated into C6/36 cells culture and the virus was identified by indirect immunofluorescent assay with alphavirus polyclonal antibodies. RT-PCR, performed with RNA extracted from the supernatant of C6/36 infected cells in the presence of alphavirus generic primers as well as specific MAYV primers, confirmed these results. The reported cases illustrate the importance of laboratory confirmation in establishing a correct diagnosis. Clinical symptoms are not always indicative of a disease caused by an arbovirus. Also MAYV causes febrile illness, which may be mistaken for dengue.O vírus Mayaro (MAYV é um arbovírus do gênero Alphavirus, família Togaviridae, enzoótico na América do Sul, sendo mantido em ciclo silvestre envolvendo vertebrados e mosquitos Haemagogus. Casos de MAYV são esporádicos e ocorrem em pessoas com história de recentes atividades dentro ou próximo a florestas. Este artigo relata infecção por MAYV detectada em três pacientes, infectados em Camapuã, MS, Brasil. Amostras de sangue, coletadas no 4º dia e no 2º mês após o início dos sintomas, foram usadas para teste de inibição da hemaglutinação, que revelou soroconversão monotípica para MAYV. O isolamento do vírus foi obtido somente de uma das

Identification of host blood from engorged mosquitoes collected in western Uganda using cytochrome oxidase I gene sequences.

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Crabtree, Mary B; Kading, Rebekah C; Mutebi, John-Paul; Lutwama, Julius J; Miller, Barry R

2013-07-01

Emerging infectious disease events are frequently caused by arthropod-borne viruses (arboviruses) that are maintained in a zoonotic cycle between arthropod vectors and vertebrate wildlife species, with spillover to humans in areas where human and wildlife populations interface. The greater Congo basin region, including Uganda, has historically been a hot spot for emergence of known and novel arboviruses. Surveillance of arthropod vectors is a critical activity in monitoring and predicting outbreaks of arboviral disease, and identification of blood meals in engorged arthropods collected during surveillance efforts provides insight into the ecology of arboviruses and their vectors. As part of an ongoing arbovirus surveillance project we analyzed blood meals from engorged mosquitoes collected at five sites in western Uganda November 2008-June 2010. We extracted DNA from the dissected and triturated abdomens of engorged mosquito specimens. Mitochondrial cytochrome c oxidase I gene sequence was amplified by PCR and sequenced to identify the source of the mosquito host blood. Blood meals were analyzed from 533 engorged mosquito specimens; 440 of these blood meals were successfully identified from 33 mosquito species. Species identifications were made for 285 of the 440 identified specimens with the remainder identified to genus, family, or order. When combined with published arbovirus isolation and serologic survey data, our results suggest possible vector-reservoir relationships for several arboviruses, including Rift Valley fever virus and West Nile virus.

Tick-Borne Transmission of Murine Gammaherpesvirus 68

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Valeria Hajnická

2017-10-01

Full Text Available Herpesviruses are a large group of DNA viruses infecting mainly vertebrates. Murine gammaherpesvirus 68 (MHV68 is often used as a model in studies of the pathogenesis of clinically important human gammaherpesviruses such as Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus. This rodent virus appears to be geographically widespread; however, its natural transmission cycle is unknown. Following detection of MHV68 in field-collected ticks, including isolation of the virus from tick salivary glands and ovaries, we investigated whether MHV68 is a tick-borne virus. Uninfected Ixodes ricinus ticks were shown to acquire the virus by feeding on experimentally infected laboratory mice. The virus survived tick molting, and the molted ticks transmitted the virus to uninfected laboratory mice on which they subsequently fed. MHV68 was isolated from the tick salivary glands, consistent with transmission via tick saliva. The virus survived in ticks without loss of infectivity for at least 120 days, and subsequently was transmitted vertically from one tick generation to the next, surviving more than 500 days. Furthermore, the F1 generation (derived from F0 infected females transmitted MHV68 to uninfected mice on which they fed, with MHV68 M3 gene transcripts detected in blood, lung, and spleen tissue of mice on which F1 nymphs and F1 adults engorged. These experimental data fulfill the transmission criteria that define an arthropod-borne virus (arbovirus, the largest biological group of viruses. Currently, African swine fever virus (ASFV is the only DNA virus recognized as an arbovirus. Like ASFV, MHV68 showed evidence of pathogenesis in ticks. Previous studies have reported MHV68 in free-living ticks and in mammals commonly infested with I. ricinus, and neutralizing antibodies to MHV68 have been detected in large mammals (e.g., deer including humans. Further studies are needed to determine if these reports are the result of tick-borne transmission

Findings at brain MRI in children with dengue fever and neurological symptoms

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Rastogi, Ruchi; Garg, Bhavya

2016-01-01

Dengue is a flavivirus of the genus arbovirus with four serotypes, from DEN 1 to DEN 4. There has been an increase in incidence of dengue infection in children in the tropics and subtropics. Dengue has a variable clinical presentation, with many patients being asymptomatic. Its clinical manifestations in children vary from fever and arthralgia to life-threatening dengue hemorrhagic fever and dengue shock syndrome. We describe MRI findings in children with neurological involvement including dengue encephalopathy, acute hypoxic injury and dengue encephalitis. Dengue encephalopathy is usually secondary to multisystem derangement such as shock, hepatitis, coagulopathy and concurrent bacterial infection and is relatively common. Dengue encephalitis from direct neuronal invasion is rare. Nonspecific changes are seen on brain MRI in dengue infection. Clinical and laboratory findings as well as outcome do not necessarily correspond with brain MRI findings. (orig.)

Findings at brain MRI in children with dengue fever and neurological symptoms

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Rastogi, Ruchi; Garg, Bhavya [Indraprastha Apollo Hospitals, Department of Radiodiagnosis, New Delhi (India)

2016-01-15

Dengue is a flavivirus of the genus arbovirus with four serotypes, from DEN 1 to DEN 4. There has been an increase in incidence of dengue infection in children in the tropics and subtropics. Dengue has a variable clinical presentation, with many patients being asymptomatic. Its clinical manifestations in children vary from fever and arthralgia to life-threatening dengue hemorrhagic fever and dengue shock syndrome. We describe MRI findings in children with neurological involvement including dengue encephalopathy, acute hypoxic injury and dengue encephalitis. Dengue encephalopathy is usually secondary to multisystem derangement such as shock, hepatitis, coagulopathy and concurrent bacterial infection and is relatively common. Dengue encephalitis from direct neuronal invasion is rare. Nonspecific changes are seen on brain MRI in dengue infection. Clinical and laboratory findings as well as outcome do not necessarily correspond with brain MRI findings. (orig.)

Limited Evidence for Infection of Urban and Peri-urban Nonhuman Primates with Zika and Chikungunya Viruses in Brazil.

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Moreira-Soto, Andres; Carneiro, Ianei de Oliveira; Fischer, Carlo; Feldmann, Marie; Kümmerer, Beate M; Silva, Nama Santos; Santos, Uilton Góes; Souza, Breno Frederico de Carvalho Dominguez; Liborio, Fernanda de Azevedo; Valença-Montenegro, Mônica Mafra; Laroque, Plautino de Oliveira; da Fontoura, Fernanda Rosa; Oliveira, Alberto Vinicius Dantas; Drosten, Christian; de Lamballerie, Xavier; Franke, Carlos Roberto; Drexler, Jan Felix

2018-01-01

Chikungunya virus (CHIKV) and Zika virus (ZIKV) emerged in the Americas in 2013. Limited antigenic variability of CHIKV and ZIKV may restrict urban transmission cycles due to population protective immunity. In Africa, sylvatic transmission cycles involving nonhuman primates (NHP) are known for CHIKV and ZIKV, causing cyclic reemergence in humans. To evaluate whether sylvatic cycles can be expected in Latin America, we tested 207 NHP collected between 2012 and 2017 in urban and peri-urban settings in Brazil for infection with ZIKV and CHIKV. No animal tested positive for viral RNA in genus-specific and species-specific reverse transcription-PCR (RT-PCR) assays. In contrast, six animals (2.9%) from the families Atelidae, Callitrichidae, and Cebidae showed ZIKV-specific antibodies and 11 (5.3%) showed CHIKV-specific antibodies in plaque reduction neutralization tests (PRNT). Reactivity was monotypic against either ZIKV or CHIKV in all cases, opposing unspecific virucidal activity of sera. PRNT endpoint titers were low at 1:40 in all NHP, and positive specimens did not correspond to the likely dispersal route and time of introduction of both arboviruses. All antibody-positive samples were therefore tested against the NHP-associated yellow fever virus (YFV) and Mayaro virus (MAYV) and against the human-associated dengue virus (DENV) by PRNT. Two ZIKV-positive samples were simultaneously DENV positive and two CHIKV-positive samples were simultaneously MAYV positive, at titers of 1:40 to 1:160. This suggested cross-reactive antibodies against heterologous alphaviruses and flaviviruses in 24% of ZIKV-positive/CHIKV-positive sera. In sum, low seroprevalence, invariably low antibody titers, and the distribution of positive specimens call into question the capability of ZIKV and CHIKV to infect New World NHP and establish sylvatic transmission cycles. IMPORTANCE Since 2013, Zika virus (ZIKV) and chikungunya virus (CHIKV) have infected millions of people in the Americas via

Aedes (Stegomyia) aegypti and Aedes (Howardina) cozumelensis in Yucatán State, México, with a summary of published collection records for Ae. cozumelensis.

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García-Rejón, Julián E; López-Uribe, Mildred P; Loroño-Pino, María Alba; Arana-Guardia, Roger; Puc-Tinal, Maria; López-Uribe, Genny M; Coba-Tún, Carlos; Baak-Baak, Carlos M; Machain-Williams, Carlos; Reyes-Solis, Guadalupe C; Lozano-Fuentes, Saul; Saavedra-Rodriguez, Karla; Black, William C; Beaty, Barry J; Eisen, Lars

2012-12-01

We collected mosquito immatures from artificial containers during 2010-2011 from 26 communities, ranging in size from small rural communities to large urban centers, located in different parts of Yucatán State in southeastern México. The arbovirus vector Aedes (Stegomyia) aegypti was collected from all 26 examined communities, and nine of the communities also yielded another container-inhabiting Aedes mosquito: Aedes (Howardina) cozumelensis. The communities from which Ae. cozumelensis were collected were all small rural communities (holes as well as various artificial containers including metal cans, flower vases, buckets, tires, and a water storage tank. The co-occurrence with Ae. aegypti in small rural communities poses intriguing questions regarding linkages between these mosquitoes, including the potential for direct competition for larval development sites. Additional studies are needed to determine how commonly Ae. cozumelensis feeds on human blood and whether it is naturally infected with arboviruses or other pathogens of medical or veterinary importance. We also summarize the published records for Ae. cozumelensis, which are restricted to collections from México's Yucatán Peninsula and Belize, and uniformly represent geographic locations where Ae. aegypti can be expected to occur. © 2012 The Society for Vector Ecology.

Experimental infection of Carrion crows (Corvus corone) with two European West Nile virus (WNV) strains.

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Dridi, Maha; Vangeluwe, Didier; Lecollinet, Sylvie; van den Berg, Thierry; Lambrecht, Bénédicte

2013-07-26

West Nile virus (WNV) has become a wide-spread arbovirus in Europe and the Mediterranean Basin countries. This emerging zoonotic disease disseminated 13 years ago in North America where its impact on animal and public health has been considerable. Although American corvids have been the most reliable avian sentinels for WN surveillance in the United States, there is so far no data available about the susceptibility of their Western European counterparts to WNV. Clinical follow-up and serum, oral swabs and feathers viral RNA load monitoring was herein performed on wild-caught Carrion crows (Corvus corone) experimentally inoculated with two WNV strains, Is98 that was isolated from a stork in Israel where it elicited high rates of avian deaths in 1998, and Fr2000 which was only associated to sporadic equine cases in Camargue, France in 2000. Inoculated crows were sensitive to both WNV infections and, as expected from the available epidemiological data, Is98 induced a higher mortality rate (100% vs. 33%) and a quicker fatal outcome, with higher viral RNA loads detected in the serum, oral swabs and feathers than in the Fr2000 group. Therefore, Carrion crows should also be a target species for WNV surveillance in Western Europe, where reporting for abnormal mortalities could be completed by viral detection in the herein described avian matrices. These experimental findings also emphasize the peculiarity of the European situation where a large spectrum of WNV genetic and pathotypic variants have been so far isolated despite limited WN disease reports in wild birds. Copyright © 2013 Elsevier B.V. All rights reserved.

Chikungunya Virus–Vector Interactions

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Lark L. Coffey

2014-11-01

Full Text Available Chikungunya virus (CHIKV is a mosquito-borne alphavirus that causes chikungunya fever, a severe, debilitating disease that often produces chronic arthralgia. Since 2004, CHIKV has emerged in Africa, Indian Ocean islands, Asia, Europe, and the Americas, causing millions of human infections. Central to understanding CHIKV emergence is knowledge of the natural ecology of transmission and vector infection dynamics. This review presents current understanding of CHIKV infection dynamics in mosquito vectors and its relationship to human disease emergence. The following topics are reviewed: CHIKV infection and vector life history traits including transmission cycles, genetic origins, distribution, emergence and spread, dispersal, vector competence, vector immunity and microbial interactions, and co-infection by CHIKV and other arboviruses. The genetics of vector susceptibility and host range changes, population heterogeneity and selection for the fittest viral genomes, dual host cycling and its impact on CHIKV adaptation, viral bottlenecks and intrahost diversity, and adaptive constraints on CHIKV evolution are also discussed. The potential for CHIKV re-emergence and expansion into new areas and prospects for prevention via vector control are also briefly reviewed.

Molecular Assay on Crimean Congo Hemorrhagic Fever Virus in Ticks (Ixodidae) Collected from Kermanshah Province, Western Iran

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Mohammadian, Maria; Chinikar, Sadegh; Telmadarraiy, Zakkyeh; Vatandoost, Hassan; Oshaghi, Mohammad Ali; Hanafi-Bojd, Ahmad Ali; Sedaghat, Mohammad Mehdi; Noroozi, Mehdi; Faghihi, Faezeh; Jalali, Tahmineh; Khakifirouz, Sahar; Shahhosseini, Nariman; Farhadpour, Firoozeh

2016-01-01

Background: Crimean-Congo Hemorrhagic Fever (CCHF) is a feverous and hemorrhagic disease endemic in some parts of Iran and caused by an arbovirus related to Bunyaviridae family and Nairovirusgenus. The main virus reservoir in the nature is ticks, however small vertebrates and a wide range of domestic and wild animals are regarded as reservoir hosts. This study was conducted to determine the infection rate of CCHF virus in hard ticks of Sarpole-Zahab County, Kermanshah province, west of Iran. Methods: From total number of 851 collected ticks from 8 villages, 131 ticks were selected randomlyand investigated for detection of CCHF virus using RT-PCR. Results: The virus was found in 3.8% of the tested ticks. Hyalommaanatolicum, H. asiaticum and Rhipicephalus sanguineus species were found to have viral infection, with the highest infection rate (11.11%) in Rh. sanguineus. Conclusion: These findings provide epidemiological evidence for planning control strategies of the disease in the study area. PMID:27308296

Molecular Assay on Crimean Congo Hemorrhagic Fever Virus in Ticks (Ixodidae Collected from Kermanshah Province, Western Iran

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Maria Mohammadian

2016-01-01

Full Text Available Background: Crimean-Congo Hemorrhagic Fever (CCHF is a feverous and hemorrhagic disease endemic in some parts of Iran and caused by an arbovirus related to Bunyaviridae family and Nairovirusgenus. The main virus reser­voir in the nature is ticks, however small vertebrates and a wide range of domestic and wild animals are regarded as reservoir hosts. This study was conducted to determine the infection rate of CCHF virus in hard ticks of Sarpole-Zahab County, Kermanshah province, west of Iran.Methods: From total number of 851 collected ticks from 8 villages, 131 ticks were selected randomlyand investi­gated for detection of CCHF virus using RT-PCR.Results: The virus was found in 3.8% of the tested ticks. Hyalommaanatolicum, H.asiaticum and Rhipicephalus sanguineus species were found to have viral infection, with the highest infection rate (11.11% in Rh. sanguineus.Conclusion: These findings provide epidemiological evidence for planning control strategies of the disease in the study area.

Limited Evidence for Infection of Urban and Peri-urban Nonhuman Primates with Zika and Chikungunya Viruses in Brazil

Science.gov (United States)

2018-01-01

ABSTRACT Chikungunya virus (CHIKV) and Zika virus (ZIKV) emerged in the Americas in 2013. Limited antigenic variability of CHIKV and ZIKV may restrict urban transmission cycles due to population protective immunity. In Africa, sylvatic transmission cycles involving nonhuman primates (NHP) are known for CHIKV and ZIKV, causing cyclic reemergence in humans. To evaluate whether sylvatic cycles can be expected in Latin America, we tested 207 NHP collected between 2012 and 2017 in urban and peri-urban settings in Brazil for infection with ZIKV and CHIKV. No animal tested positive for viral RNA in genus-specific and species-specific reverse transcription-PCR (RT-PCR) assays. In contrast, six animals (2.9%) from the families Atelidae, Callitrichidae, and Cebidae showed ZIKV-specific antibodies and 11 (5.3%) showed CHIKV-specific antibodies in plaque reduction neutralization tests (PRNT). Reactivity was monotypic against either ZIKV or CHIKV in all cases, opposing unspecific virucidal activity of sera. PRNT endpoint titers were low at 1:40 in all NHP, and positive specimens did not correspond to the likely dispersal route and time of introduction of both arboviruses. All antibody-positive samples were therefore tested against the NHP-associated yellow fever virus (YFV) and Mayaro virus (MAYV) and against the human-associated dengue virus (DENV) by PRNT. Two ZIKV-positive samples were simultaneously DENV positive and two CHIKV-positive samples were simultaneously MAYV positive, at titers of 1:40 to 1:160. This suggested cross-reactive antibodies against heterologous alphaviruses and flaviviruses in 24% of ZIKV-positive/CHIKV-positive sera. In sum, low seroprevalence, invariably low antibody titers, and the distribution of positive specimens call into question the capability of ZIKV and CHIKV to infect New World NHP and establish sylvatic transmission cycles. IMPORTANCE Since 2013, Zika virus (ZIKV) and chikungunya virus (CHIKV) have infected millions of people in the

Genome-wide SNPs lead to strong signals of geographic structure and relatedness patterns in the major arbovirus vector, Aedes aegypti.

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Rašić, Gordana; Filipović, Igor; Weeks, Andrew R; Hoffmann, Ary A

2014-04-11

Genetic markers are widely used to understand the biology and population dynamics of disease vectors, but often markers are limited in the resolution they provide. In particular, the delineation of population structure, fine scale movement and patterns of relatedness are often obscured unless numerous markers are available. To address this issue in the major arbovirus vector, the yellow fever mosquito (Aedes aegypti), we used double digest Restriction-site Associated DNA (ddRAD) sequencing for the discovery of genome-wide single nucleotide polymorphisms (SNPs). We aimed to characterize the new SNP set and to test the resolution against previously described microsatellite markers in detecting broad and fine-scale genetic patterns in Ae. aegypti. We developed bioinformatics tools that support the customization of restriction enzyme-based protocols for SNP discovery. We showed that our approach for RAD library construction achieves unbiased genome representation that reflects true evolutionary processes. In Ae. aegypti samples from three continents we identified more than 18,000 putative SNPs. They were widely distributed across the three Ae. aegypti chromosomes, with 47.9% found in intergenic regions and 17.8% in exons of over 2,300 genes. Pattern of their imputed effects in ORFs and UTRs were consistent with those found in a recent transcriptome study. We demonstrated that individual mosquitoes from Indonesia, Australia, Vietnam and Brazil can be assigned with a very high degree of confidence to their region of origin using a large SNP panel. We also showed that familial relatedness of samples from a 0.4 km2 area could be confidently established with a subset of SNPs. Using a cost-effective customized RAD sequencing approach supported by our bioinformatics tools, we characterized over 18,000 SNPs in field samples of the dengue fever mosquito Ae. aegypti. The variants were annotated and positioned onto the three Ae. aegypti chromosomes. The new SNP set provided much

Viral RNA Silencing Suppression: The Enigma of Bunyavirus NSs Proteins

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Marcio Hedil

2016-07-01

Full Text Available The Bunyaviridae is a family of arboviruses including both plant- and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative transmission. For this reason, they are generally assumed to encounter antiviral RNA silencing in plants and insects. Here we present an overview on how tospovirus nonstructural NSs protein counteracts antiviral RNA silencing in plants and what is known so far in insects. Like tospoviruses, members of the related vertebrate-infecting bunyaviruses classified in the genera Orthobunyavirus, Hantavirus and Phlebovirus also code for a NSs protein. However, for none of them RNA silencing suppressor activity has been unambiguously demonstrated in neither vertebrate host nor arthropod vector. The second part of this review will briefly describe the role of these NSs proteins in modulation of innate immune responses in mammals and elaborate on a hypothetical scenario to explain if and how NSs proteins from vertebrate-infecting bunyaviruses affect RNA silencing. If so, why this discovery has been hampered so far.

Viral RNA Silencing Suppression: The Enigma of Bunyavirus NSs Proteins.

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Hedil, Marcio; Kormelink, Richard

2016-07-23

The Bunyaviridae is a family of arboviruses including both plant- and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative transmission. For this reason, they are generally assumed to encounter antiviral RNA silencing in plants and insects. Here we present an overview on how tospovirus nonstructural NSs protein counteracts antiviral RNA silencing in plants and what is known so far in insects. Like tospoviruses, members of the related vertebrate-infecting bunyaviruses classified in the genera Orthobunyavirus, Hantavirus and Phlebovirus also code for a NSs protein. However, for none of them RNA silencing suppressor activity has been unambiguously demonstrated in neither vertebrate host nor arthropod vector. The second part of this review will briefly describe the role of these NSs proteins in modulation of innate immune responses in mammals and elaborate on a hypothetical scenario to explain if and how NSs proteins from vertebrate-infecting bunyaviruses affect RNA silencing. If so, why this discovery has been hampered so far.

Identification of pathogens for differential diagnosis of fever with jaundice in the Central African Republic: a retrospective assessment, 2008-2010.

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Gadia, Christelle Luce Bobossi; Manirakiza, Alexandre; Tekpa, Gaspard; Konamna, Xavier; Vickos, Ulrich; Nakoune, Emmanuel

2017-11-29

Febrile jaundice results clinically in generalized yellow coloration of the teguments and mucous membranes due to excess plasma bilirubin, accompanied by fever. Two types are found: conjugated and unconjugated bilirubin jaundice. Jaundice is a sign in several diseases due to viruses (viral hepatitis and arbovirus), parasites (malaria) and bacteria (leptospirosis). In the Central African Republic (CAR), only yellow fever is included on the list of diseases for surveillance. The aim of this study was to identify the other pathogens that can cause febrile jaundice, for better management of patients. Between 2008 and 2010, 198 sera negative for yellow fever IgM were randomly selected from 2177 samples collected during yellow fever surveillance. Laboratory analyses targeted four groups of pathogens: hepatitis B, C, delta and E viruses; dengue, chikungunya, Zika, Crimean-Congo haemorrhagic fever, West Nile and Rift Valley arboviruses; malaria parasites; and bacteria (leptospirosis). Overall, 30.9% sera were positive for hepatitis B, 20.2% for hepatitis E, 12.3% for hepatitis C and 8.2% for malaria. The majority of positive sera (40.4%) were from people aged 16-30 years. Co-infection with at least two of these pathogens was also found. These findings suggest that a systematic investigation should be undertaken of infectious agents that cause febrile jaundice in the CAR.

The recent outbreaks of Zika virus: Mosquito control faces a further challenge

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Giovanni Benelli

2016-04-01

Full Text Available The recent outbreaks of Zika virus infection occurring in South America, Central America and the Caribbean, represent the most recent of four key arrivals of arboviruses in the Western Hemisphere over the last 20 years. Zika virus is mainly vectored by Aedes mosquitoes. The development of effective and eco-friendly mosquito control methods is required in order to minimize the negative effects of currently marketed synthetic pesticides, including multidrug resistance. In this scenario, natural product research can afford solutions as part of integrated pest management strategies. In this review, we focused on neem (Azadirachta indica products as sources of cheap control tools of Aedes vectors. Current knowledge on the larvicidal, pupicidal, adulticidal and oviposition deterrent potential of neem-borne products against the arbovirus vectors Aedes aegypti and Aedes albopictus is reviewed. Furthermore, we considered the rising importance of neem extraction by-products as sources of bio-reducing agents for the synthesis of nanoformulated mosquitocides. The last section examined biosafety and nontarget effects on neem-borne mosquitocides in the aquatic environment. Overall, we support the employ of neem-borne molecules as an advantageous alternative to build newer and safer Aedes control tools, in the framework of Zika virus outbreak prevention.

The Epidemiology, Clinical Characteristic,Transmission Potential and Control Measures of Zika Virus Infection%The Epidemiology,Clinical Characteristic,Transmission Potential and Control Measures of Zika Virus Infection

Institute of Scientific and Technical Information of China (English)

ALOTAIBIABDULLAHSAUDM; ALANAZIMANSOURRASHEDM; AHMADMEESAQ

2017-01-01

Zika virus (ZIKV) is an emerging mosquito born positive standard RNA arbovirus of Flaviviriadae family.Zika virus has been identified sporadically in human in Africa and Asia;however,clinically consequential Zika virus disease had not been documented before to the recent outbreak in the America in 2015.It is rapidly spread across the America and its devastating outcomes for pregnant women and infants.Prior to outbreak of America,Zika virus outbreaks occurred in Yap Island in Micronesia in 2007 and in French Polynesia in 2013.The World Health Organisation (WHO) declarer a Public Health Emergency of International Concern on February 1,2016.Because of the continuous geographicexpansion of both the virus and its mosquito vectors,ZIKV poses a serious threat to public health aroundthe globe.This review summarizes a fast growing body of literature on the history,epidemiology,transmission,clinical presentation and control measures to prevent the transmission of Zika virus.

Pathogen inactivation of Dengue virus in red blood cells using amustaline and glutathione.

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Aubry, Maite; Laughhunn, Andrew; Santa Maria, Felicia; Lanteri, Marion C; Stassinopoulos, Adonis; Musso, Didier

2017-12-01

Dengue virus (DENV) is an arbovirus primarily transmitted through mosquito bite; however, DENV transfusion-transmitted infections (TTIs) have been reported and asymptomatic DENV RNA-positive blood donors have been identified in endemic countries. DENV is considered a high-risk pathogen for blood safety. One of the mitigation strategies to prevent arbovirus TTIs is pathogen inactivation. In this study we demonstrate that the amustaline and glutathione (S-303/GSH) treatment previously found effective against Zika virus in red blood cells (RBCs) is also effective in inactivating DENV. Red blood cells were spiked with high levels of DENV. Viral RNA loads and infectious titers were measured in the untreated control and before and after pathogen inactivation treatment of RBC samples. DENV infectivity was also assessed over five successive cell culture passages to detect any potential residual replicative virus. The mean ± SD DENV titer in RBCs before inactivation was 6.61 ± 0.19 log 50% tissue culture infectious dose (TCID 50 )/mL and the mean viral RNA load was 8.42 log genome equivalents/mL. No replicative DENV was detected either immediately after completion of treatment using S-303/GSH or after cell culture passages. Treatment using S-303/GSH inactivated high levels of DENV in RBCs to the limit of detection. In combination with previous studies showing the effective inactivation of DENV in plasma and platelets using the licensed amotosalen/UVA system, this study demonstrates that high levels of DENV can be inactivated in all blood components. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

West Nile Virus lineage-2 in Culex specimens from Iran.

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Shahhosseini, Nariman; Chinikar, Sadegh; Moosa-Kazemi, Seyed Hassan; Sedaghat, Mohammad Mehdi; Kayedi, Mohammad Hassan; Lühken, Renke; Schmidt-Chanasit, Jonas

2017-10-01

Screening of mosquitoes for viruses is an important forecasting tool for emerging and re-emerging arboviruses. Iran has been known to harbour medically important arboviruses such as West Nile virus (WNV) and dengue virus (DENV) based on seroepidemiological data. However, there are no data about the potential mosquito vectors for arboviruses in Iran. This study was performed to provide mosquito and arbovirus data from Iran. A total of 32 317 mosquitos were collected at 16 sites in five provinces of Iran in 2015 and 2016. RT-PCR for detection of flaviviruses was performed. The PCR amplicons were sequenced, and 109 WNV sequences, including one obtained in this study, were used for phylogenetic analyses. The 32 317 mosquito specimens belonging to 25 species were morphologically distinguished and distributed into 1222 pools. Culex pipiens s.l. comprised 56.429%. One mosquito pool (0.08%), containing 46 unfed Cx. pipiens pipiens form pipiens (Cpp) captured in August 2015, was positive for flavivirus RNA. Subsequent sequencing and phylogenetic analyses revealed that the detected Iranian WNV strain belongs to lineage 2 and clusters with a strain recently detected in humans. No flaviviruses other than WNV were detected in the mosquito pools. Cpp could be a vector for WNV in Iran. Our findings indicate recent circulation of WNV lineage-2 strain in Iran and provide a solid base for more targeted arbovirus surveillance programs. © 2017 John Wiley & Sons Ltd.

New report on the bionomics of Coquillettidia venezuelensis in temporary breeding sites (Diptera: Culicidae

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Jeronimo Alencar

2011-04-01

Full Text Available INTRODUCTION: Findings of immature forms of Coquillettidia venezuelensis in temporary breeding sites, without the presence of aquatic plants or other submerged plant tissue are reported. METHODS: A systematic scooping technique to collect specimens was used at the breeding site. RESULTS: Immature forms of Coquillettidia venezuelensis, Anopheles rangeli, An. evansae and Culex sp. were collected from areas of the hydroelectric power station of São Salvador, State of Goiás. CONCLUSIONS This is a novel finding relating to the bioecology of Cq. venezuelensis, a species of medical interest that has been found naturally infected with arboviruses, including Oropouche and West Nile virus.

Epidemiology of Zika Virus.

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Younger, David S

2016-11-01

Zika virus is an arbovirus belonging to the Flaviviridae family known to cause mild clinical symptoms similar to those of dengue and chikungunya. Zika is transmitted by different species of Aedes mosquitoes. Nonhuman primates and possibly rodents play a role as reservoirs. Direct interhuman transmission has also been reported. Human cases have been reported in Africa and Asia, Easter Island, the insular Pacific region, and Brazil. Its clinical profile is that of a dengue-like febrile illness, but recently associated Guillain-Barre syndrome and microcephaly have appeared. There is neither a vaccine nor prophylactic medications available to prevent Zika virus infection. Copyright © 2016 Elsevier Inc. All rights reserved.

Vaginal Infections

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... gov/ Home Body Your reproductive health Vaginal infections Vaginal infections Help for infections If you have pain, ... infections and how to prevent them. Types of vaginal infections top Two common vaginal infections are bacterial ...

Infective Endocarditis

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... Center > Infective Endocarditis Menu Topics Topics FAQs Infective Endocarditis En español Infective endocarditis is an infection of ... time, congestive heart failure (CHF). What causes infective endocarditis? The infection that leads to endocarditis can be ...

Potential for sublethal insecticide exposure to impact vector competence of Aedes albopictus (Diptera: Culicidae for dengue and Zika viruses

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Richards SL

2017-05-01

Full Text Available Stephanie L Richards, Avian V White, Jo Anne G Balanay Department of Health Education and Promotion, College of Health and Human Performance, East Carolina University, Greenville, NC, USA Abstract: Chikungunya, dengue, and Zika viruses (CHIKV, family Togaviridae, genus Alphavirus; DENV and ZIKV, family Flaviviridae, genus Flavivirus are arboviruses that cause human epidemics. Due to the lack of vaccines for many mosquito-borne diseases, there is a need for mosquito control. In the US and other regions, residual barrier insecticide sprays are applied to foliage where female mosquitoes rest and/or sugar feed between blood meals. Residual sprays are an important control method for anthropogenic day-active sylvan mosquitoes such as Aedes albopictus (vector of CHIKV, DENV, and ZIKV that are difficult to control using ultralow-volume sprays applied only at dusk or dawn when these mosquitoes are not active. In this exploratory study, we analyzed the extent to which ingestion of a sublethal dose of the active ingredient bifenthrin affected vector competence (i.e., infection, dissemination, and transmission of Ae. albopictus for DENV and ZIKV. Two incubation periods (IPs; 7 and 14 d were tested at 28°C for insecticide-fed and sugar-fed mosquitoes. We show that mosquitoes that were fed bifenthrin (0.128 µg/mL mixed with sucrose solution exhibited significantly lower DENV infection rates and body titers after a 14-d IP. During the 7-d IP, one mosquito (sugar group transmitted ZIKV. During the 14-d IP, 100% of mosquitoes showed body and leg ZIKV infections, and one mosquito (sugar+bifenthrin group transmitted ZIKV. This is a preliminary communication, and more studies will be required to further investigate these findings. We expect the findings of this small-scale study to spur larger-scale investigations of the impacts of insecticides on mechanisms regulating vector competence, and exposure to other active ingredients, and aid in development of new

Hepatitis C virus infection in HIV-infected patients.

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Sulkowski, Mark S

2007-10-01

The hepatitis C virus (HCV) is a spherical enveloped RNA virus of the Flaviviridae family, classified within the Hepacivirus genus. Since its discovery in 1989, HCV has been recognized as a major cause of chronic hepatitis and hepatic fibrosis that progresses in some patients to cirrhosis and hepatocellular carcinoma. In the United States, approximately 4 million people have been infected with HCV, and 10,000 HCVrelated deaths occur each year. Due to shared routes of transmission, HCV and HIV co-infection are common, affecting approximately one third of all HIV-infected persons in the United States. In addition, HIV co-infection is associated with higher HCV RNA viral load and a more rapid progression of HCV-related liver disease, leading to an increased risk of cirrhosis. HCV infection may also impact the course and management of HIV disease, particularly by increasing the risk of antiretroviral drug-induced hepatotoxicity. Thus, chronic HCV infection acts as an opportunistic disease in HIV-infected persons because the incidence of infection is increased and the natural history of HCV infection is accelerated in co-infected persons. Strategies to prevent primary HCV infection and to modify the progression of HCV-related liver disease are urgently needed among HIV/HCV co-infected individuals.

SURVAI VECTOR DAN RESERVOIR PENYAKIT ZOONOTIK YANG DITULARKAN OLEH ARTHROPODA DI DESA BASI, KECAMATAN DONDO KABUPATEN BUOL — TOLITOLI, SULAWESI TENGAH, INDONESIA

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Tuti R. Hadi

2012-09-01

Full Text Available An ecological survey was conducted in Central Sulawesi to obtain information on the distri­bution of reservoir hosts and vectors of arthropod-borne zoonotic diseases. Serological test were done from human sera collected in the area against arboviral and rickettsial antigens. Three species of Culex mosquitoes known as potential vectors of arbovirosis: Cx. bitaeni-orhynchus, Cx. gelidus and Cx. tritaeniorhynchus, were found in the area surveyed. A known vector of scrub typhus, Leptotrombidium (L. deliensis, was also found in that area. Suspected reservoirs of arthropod-borne zoonosis in the area surveyed were chickens, ducks, cows, horses, monkeys and rats. The prevalence of antibodies against arbovirus group A antigens ( Chikungunya, Getah and Sindbis was 34,06%, 28,5% and 4,39%, against arbovirus group B antigen (Japanese Encepha­litis was 93,4% and none against Rickettsia tsutsugamushi and Rickettsia typhy antigens, out of 91 human sera examined. Antibodies were found in animal sera examined against arbovirus group A and arbovirus group B antigens in a variation of 11,8% — 100%. The prevalence of antibodies against R. tsutsugamushi antigen was 22,7% out of 22 rat sera examined.

Biogeography of the two major arbovirus mosquito vectors, Aedes aegypti and Aedes albopictus (Diptera, Culicidae, in Madagascar

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Raharimalala Fara

2012-03-01

Full Text Available Abstract Background In the past ten years, the Indian Ocean region has been the theatre of severe epidemics of chikungunya and dengue. These outbreaks coincided with a high increase in populations of Aedes albopictus that outcompete its sister taxon Aedes aegypti in most islands sampled. The objective of this work was to update the entomological survey of the two Aedes species in the island of Madagascar which has to face these arboviroses. Methods The sampling of Aedes mosquitoes was conducted during two years, from October 2007 to October 2009, in fifteen localities from eight regions of contrasting climates. Captured adults were identified immediately whereas immature stages were bred until adult stage for determination. Phylogenetic analysis was performed using two mtDNA genes, COI and ND5 and trees were constructed by the maximum likelihood (ML method with the gene time reversible (GTR model. Experimental infections with the chikungunya virus strain 06.21 at a titer of 107.5 pfu/mL were performed to evaluate the vector competence of field-collected mosquitoes. Disseminated infection rates were measured fourteen days after infection by immunofluorescence assay performed on head squashes. Results The species Aedes aegypti was detected in only six sites in native forests and natural reserves. In contrast, the species Aedes albopictus was found in 13 out of the 15 sites sampled. Breeding sites were mostly found in man-made environments such as discarded containers, used tires, abandoned buckets, coconuts, and bamboo cuts. Linear regression models showed that the abundance of Ae. albopictus was significantly influenced by the sampling region (F = 62.00, p -16 and period (F = 36.22, p = 2.548 × 10-13, that are associated with ecological and climate variations. Phylogenetic analysis of the invasive Ae. albopictus distinguished haplotypes from South Asia and South America from those of Madagascar, but the markers used were not discriminant enough

Brucella Infection in HIV Infected Patients

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SeyedAhmad SeyedAlinaghi

2011-12-01

Full Text Available The purpose of this study was to assess the possible correlation between Brucella and HIV infections. Iran is a country where HIV infection is expanding and Brucellosis is prevalent. In the present study, 184 HIV infected patients were assigned and for all of them HIV infection was confirmed by western blot test. In order to identify the prevalence rate of Brucella infection and systemic brucellosis in these subjects, sera samples were obtained and Brucella specific serological tests were performed to reveal antibody titers. Detailed history was taken and physical examination was carried out for all of patients. 11 (6% subjects had high titers but only 3 of them were symptomatic. Most of these subjects were injection drug user (IDU men and one was a rural woman. Considering both prevalence rates of Brucella infection (3% and symptomatic brucellosis (0.1% in Iran, our HIV positive patients show higher rates of Brucella infection and systemic brucellosis. Preserved cellular immunity of participants and retention of granulocytes activity may explain this poor association; whereas other explanations such as immunological state difference and non-overlapping geographical distribution of the 2 pathogens have been mentioned by various authors.

Tick-borne encephalitis.

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Dumpis, U; Crook, D; Oksi, J

1999-04-01

Tick-borne encephalitis (TBE) is a zoonotic arbovirus infection endemic to Russia and Eastern and Central Europe. Despite being a common and serious life-threatening disease for which a mass vaccination program was implemented in Austria, there is only limited reference to this disease in the English-language literature. TBE is transmitted to humans usually by the bite of a tick (either Ixodes persulcatus or Ixodes ricinus); occasionally, cases occur following consumption of infected unpasteurized milk. Transmission is seasonal and occurs in spring and summer, particularly in rural areas favored by the vector. TBE is a serious cause of acute central nervous system disease, which may result in death or long-term neurological sequelae. Effective vaccines are available in a few countries. The risk for travelers of acquiring TBE is increasing with the recent rise in tourism to areas of endemicity during spring and summer.

Wolbachia Blocks Currently Circulating Zika Virus Isolates in Brazilian Aedes aegypti Mosquitoes.

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Dutra, Heverton Leandro Carneiro; Rocha, Marcele Neves; Dias, Fernando Braga Stehling; Mansur, Simone Brutman; Caragata, Eric Pearce; Moreira, Luciano Andrade

2016-06-08

The recent association of Zika virus with cases of microcephaly has sparked a global health crisis and highlighted the need for mechanisms to combat the Zika vector, Aedes aegypti mosquitoes. Wolbachia pipientis, a bacterial endosymbiont of insect, has recently garnered attention as a mechanism for arbovirus control. Here we report that Aedes aegypti harboring Wolbachia are highly resistant to infection with two currently circulating Zika virus isolates from the recent Brazilian epidemic. Wolbachia-harboring mosquitoes displayed lower viral prevalence and intensity and decreased disseminated infection and, critically, did not carry infectious virus in the saliva, suggesting that viral transmission was blocked. Our data indicate that the use of Wolbachia-harboring mosquitoes could represent an effective mechanism to reduce Zika virus transmission and should be included as part of Zika control strategies. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

PEMERIKSAAN VIRUS DENGUE-3 PADA NYAMUK Aedes aegypti YANG DIINFEKSI SECARA INTRATHORAKAL DENGAN TEKNIK IMUNOSITOKIMIA MENGGUNAKAN ANTIBODI DSSE10

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Dyah Widiastuti

2013-09-01

Full Text Available ABSTRACTDengue viruses, globally the most prevalent arboviruses, are transmitted to humans by persistently infectedAedes mosquitoes. The most important vector of Dengue virus is the mosquito Ae.aegypti, which should be the main targetof surveillance and control activities. Virologic surveillance for dengue viruses in its vector has been used as an earlywarning system to predict outbreaks. Detection of Dengue virus antigen in mosquito head squash usingimmunocytochemical streptavidin biotin peroxidase complex (SBPC assay is an alternative method for dengue vectorsurveillance. The study aimed to develope immunocytochemical SBPC assay to detect Dengue virus infection in headsquash of Ae.aegypti. The study design was experimental. Artificially-infected adult Ae. aegypti mosquitoes of DENV 3were used as infectious samples and non-infected adult Ae. aegypti mosquitoes were used as normal ones. Theimmunocytochemical SBPC assay using monoclonal antibody DSSE10 then was applied in mosquito head squash todetect Dengue virus antigen. The results were analyzed by descriptive analysis. The immunocytochemical SBPC assaycan detect Dengue virus antigen in mosquito head squash at day 2 postinfection. There are some false positive resultsfound in immunocytochemical SBPC assay.Key Word: Dengue, immunocytochemistry, DSSE10

Detection and Characterization of Infections and Infection Susceptibility

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2018-03-27

Immune Disorders; Chronic Granulomatous Disease; Genetic Immunological Deficiencies; Hyperimmunoglobulin-E Recurrent Infection Syndrome; Recurrent Infections; Unknown Immune Deficiency; GATA2 Deficiency (MonoMAC); Nontuberculous Mycobacterial Infections; Hyper IgE (Job s) Syndrome; Leukocyte Adhesion Deficiency; Susceptibility to Disseminated Infections; Primary Immune Deficiency Disease (PIDD)

Detection of dengue group viruses by fluorescence in situ hybridization

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Raquin Vincent

2012-10-01

Full Text Available Abstract Background Dengue fever (DF and dengue hemorrhagic fever (DHF represent a global challenge in public health. It is estimated that 50 to 100 million infections occur each year causing approximately 20,000 deaths that are usually linked to severe cases like DHF and dengue shock syndrome. The causative agent of DF is dengue virus (genus Flavivirus that comprises four distinct serotypes (DENV-1 to DENV-4. Fluorescence in situ hybridization (FISH has been used successfully to detect pathogenic agents, but has not been implemented in detecting DENV. To improve our understanding of DENV infection and dissemination in host tissues, we designed specific probes to detect DENV in FISH assays. Methods Oligonucleotide probes were designed to hybridize with RNA from the broadest range of DENV isolates belonging to the four serotypes, but not to the closest Flavivirus genomes. Three probes that fit the criteria defined for FISH experiments were selected, targeting both coding and non-coding regions of the DENV genome. These probes were tested in FISH assays against the dengue vector Aedes albopictus (Diptera: Culicidae. The FISH experiments were led in vitro using the C6/36 cell line, and in vivo against dissected salivary glands, with epifluorescence and confocal microscopy. Results The three 60-nt oligonucleotides probes DENV-Probe A, B and C cover a broad range of DENV isolates from the four serotypes. When the three probes were used together, specific fluorescent signals were observed in C6/36 infected with each DENV serotypes. No signal was detected in either cells infected with close Flavivirus members West Nile virus or yellow fever virus. The same protocol was used on salivary glands of Ae. albopictus fed with a DENV-2 infectious blood-meal which showed positive signals in the lateral lobes of infected samples, with no significant signal in uninfected mosquitoes. Conclusion Based on the FISH technique, we propose a way to design and use

Epidemic Spread of Usutu Virus in Southwest Germany in 2011 to 2013 and Monitoring of Wild Birds for Usutu and West Nile Viruses.

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Ziegler, Ute; Jöst, Hanna; Müller, Kerstin; Fischer, Dominik; Rinder, Monika; Tietze, Dieter Thomas; Danner, Klaus-Jürgen; Becker, Norbert; Skuballa, Jasmin; Hamann, Hans-Peter; Bosch, Stefan; Fast, Christine; Eiden, Martin; Schmidt-Chanasit, Jonas; Groschup, Martin H

2015-08-01

Mosquito-borne viruses are becoming an increasing threat for Europe. One of these viruses is Usutu virus (USUV), a single-stranded RNA virus belonging to the Japanese encephalitis virus group within the family Flaviviridae. Since the occurrence of USUV among wild birds in June, 2011, infected Blackbirds (Turdus merula) have frequently been found dead in southwest Germany, cumulating in a massive die-off. Moreover, other bird species (Strigiformes) in this region have been affected. In a first study, 209 of over 600 dead birds (wild birds and birds kept in aviaries) collected from 2011 to 2013 carried USUV, more than 88% of them Blackbirds. USUV had already been detected in 2010, one year before the epizooty, in a mosquito-based surveillance program in Germany. The main epidemic area of the USUV outbreak in wild birds in southwest Germany has been similar for the last three years. In a second study during 2011 to 2013, 902 live migratory and resident birds (representing 87 bird species belonging to 14 bird orders) from four different sampling sites were bled and tested serologically and by qPCR for West Nile virus (WNV) and USUV infections. No USUV or WNV genomes were detected. Some migratory birds (mainly long-distance migrants and some partial migrants) carried neutralizing antibodies against WNV as discriminated by USUV and WNV cross-neutralization tests. Only few resident birds showed relevant USUV-specific neutralizing antibodies. The occurrence of USUV in the Upper Rhine valley area of southwest Germany is a proof of principle for the incursion and spread of other arthropod-borne (arbo)-viruses along these routes. Therefore, monitoring studies in birds and mosquitoes for the presence of arboviruses in these areas are indispensable.

Anal Human Papillomavirus Infection among HIV-Infected Men in Korea.

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Chang Hun Lee

Full Text Available Little is known about the epidemiology on human papillomavirus (HPV infection among HIV-infected men in Korea. The objective of this study was to determine the prevalence, genotype distribution and risk factors associated with anal HPV infection among HIV-infected men in Korea.A single-center cross-sectional study was conducted with HIV-infected men in Korea. Participants completed a detailed sexual behavior risk factor questionnaire. Anal samples were collected for cytology and HPV genotyping. Factors associated with anal HPV infection were assessed using multivariable logistic regression, stratifying by sexual behaviour.A total of 201 HIV-infected men were included in the study: 133 were from men who have sex with men (MSM and 68 from men who have sex with women (MSW. Any anal HPV infection was detected in 82.7% of HIV-infected MSM and in 51.5% of HIV- infected MSW (P < 0.001. High-risk HPV (HR-HPV prevalence was higher among MSM (47.4% than MSW (25.0%; P = 0.002. The HR-HPV types identified most frequently were HPV 16 (11%, HPV 18 (9.9%, and HPV 58 (5% in MSM, and HPV 58(11% and HPV 16 (8.9% in MSW. Prevalence of any HPV types in 9-valent vaccine types was higher among MSM than MSW (47.4% vs 22.1%. P = 0.001. Abnormal anal cytology was more commonly detected in MSM than MSW (42.9% vs.19.1%, P < 0.001. In HIV-infected MSM, higher number of lifetime male sex partners was significantly associated with any anal HPV infection, but age was a significant risk factor associated with anal HR-HPV infection.Anal HPV infection was highly prevalent in HIV-infected MSM in Korea, and also commonly found in HIV-infected MSW. In HIV-infected MSM, the significant risk factor for being infected with any HPV infection was lifetime number of male sexual partners, and with anal oncogenic HPV infection was age.

Nosocomial infections in HIV-infected and HIV-uninfected children ...

African Journals Online (AJOL)

Twenty-five nosocomial infections (23%) among the HIV-infected children, but only ... candidiasis in seven and zero, urinary tract infection in four and one and .... tant or multidrug-resistant TB received ... bacterial infections, 96 hours in the case.

Handling small arbovirus vectors safely during biosafety level 3 containment: Culicoides variipennis sonorensis (Diptera:Ceratopogonidae) and exotic bluetongue viruses.

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Hunt, G J; Tabachnick, W J

1996-05-01

Equipment and procedures are described for biosafety level 3 (BL-3) containment work with small, zoophilic arthropods. BL-3 classified pathogens always must be manipulated in biological safety cabinets. Procedures, including physical barriers and handling methods, that prevent the escape of potentially virus-infected insects are discussed, and the use of a monitoring system for insect security is explained. The inability to recover escaped minute, flying insects poses a major difference from similar work with larger insects, such as mosquitoes. Methods were developed for the safe and secure handling of Culicoides variipennis sonorensis Wirth & Jones infected with exotic bluetongue viruses during BL-3 containment.

Olympic Games Rio 2016 and the uninvited viruses: Potential consequences for Europe and North America

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Salim Mattar

2016-05-01

Full Text Available In the Latin American tropics, we have witnessed the emergence of several pathogenic arboviruses in the last decade. These include Yellow Fever, West Nile virus, St. Louis encephalitis, Venezuelan equine encephalitis, Mayaro, Oropouche, Ilheus, and most recently, Chikungunya and Zika. Guillain-Barre syndrome (GBS, microcephaly and all the encephalitides, have been of concern to public health officials in Latin America since the arrival of emerging arboviruses. ¡Don‘t forget about dengue!

Bladder Infection (Urinary Tract Infection - UTI) in Adults

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... The Urinary Tract & How It Works Bladder Infection (Urinary Tract Infection—UTI) in Adults View or Print All ... Bladder infections are the most common type of urinary tract infection (UTI), but any part of your urinary ...

Nosocomial infections in HIV-infected and HIV-uninfected children ...

African Journals Online (AJOL)

The interaction between tuberculosis and HIV-infected infection is well known and is responsible for the increase in the incidence of tuberculosis ... This retrospective case-control study evaluated the occurrence of nosocomial infections in (HIV)-infected children and age- and time of ... complicated disease, or whose social.

Nosocomial infections in HIV-infected and HIV-uninfected children ...

African Journals Online (AJOL)

One HIV-infected child died of varicella pneumonia. Other common nosocomial infections encountered in HIV-infected and HIV-uninfected children respectively were upper respiratory tract infections (pharyngitis, tonsillitis or rhinitis) affecting 21 and four, otitis media in five and one, oral candidiasis in seven and zero, urinary ...

Salivary gland extracts of Culicoides sonorensis inhibit murine lymphocyte proliferation and no production by macrophages.

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Bishop, Jeanette V; Mejia, J Santiago; Pérez de León, Adalberto A; Tabachnick, Walter J; Titus, Richard G

2006-09-01

Culicoides biting midges serve as vectors of pathogens affecting humans and domestic animals. Culicoides sonorensis is a vector of several arboviruses in North American that cause substantial economic losses to the US livestock industry. Previous studies showed that C. sonorensis saliva, like the saliva of many hematophagous arthropods, contains numerous pharmacological agents that affect hemostasis and early events in the inflammatory response, which may enhance the infectivity of Culicoides-borne pathogens. This paper reports on the immunomodulatory properties of C. sonorensis salivary gland extracts on murine immune cells and discusses the possible immunomodulatory role of C. sonorensis saliva in vesicular stomatitis virus infection of vertebrate hosts. Splenocytes treated with C. sonorensis mitogens were significantly affected in their proliferative response, and peritoneal macrophages secreted significantly less NO. A 66-kDa glycoprotein was purified from C. sonorensis salivary gland extract, which may be in part responsible for these observations and may be considered as a vaccine candidate.

Vector Contact Rates on Eastern Bluebird Nestlings Do Not Indicate West Nile Virus Transmission in Henrico County, Virginia, USA

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Kevin A. Caillouët

2013-11-01

Full Text Available Sensitive indicators of spatial and temporal variation in vector-host contact rates are critical to understanding the transmission and eventual prevention of arboviruses such as West Nile virus (WNV. Monitoring vector contact rates on particularly susceptible and perhaps more exposed avian nestlings may provide an advanced indication of local WNV amplification. To test this hypothesis we monitored WNV infection and vector contact rates among nestlings occupying nest boxes (primarily Eastern bluebirds; Sialia sialis, Turdidae across Henrico County, Virginia, USA, from May to August 2012. Observed host-seeking rates were temporally variable and associated with absolute vector and host abundances. Despite substantial effort to monitor WNV among nestlings and mosquitoes, we did not detect the presence of WNV in these populations. Generally low vector-nestling host contact rates combined with the negative WNV infection data suggest that monitoring transmission parameters among nestling Eastern bluebirds in Henrico County, Virginia, USA may not be a sensitive indicator of WNV activity.

Hindrances to bistable front propagation: application to Wolbachia invasion.

Science.gov (United States)

Nadin, Grégoire; Strugarek, Martin; Vauchelet, Nicolas

2018-05-01

We study the biological situation when an invading population propagates and replaces an existing population with different characteristics. For instance, this may occur in the presence of a vertically transmitted infection causing a cytoplasmic effect similar to the Allee effect (e.g. Wolbachia in Aedes mosquitoes): the invading dynamics we model is bistable. We aim at quantifying the propagules (what does it take for an invasion to start?) and the invasive power (how far can an invading front go, and what can stop it?). We rigorously show that a heterogeneous environment inducing a strong enough population gradient can stop an invading front, which will converge in this case to a stable front. We characterize the critical population jump, and also prove the existence of unstable fronts above the stable (blocking) fronts. Being above the maximal unstable front enables an invading front to clear the obstacle and propagate further. We are particularly interested in the case of artificial Wolbachia infection, used as a tool to fight arboviruses.

CIED infection with either pocket or systemic infection presentation

DEFF Research Database (Denmark)

Ihlemann, Nikolaj; Møller-Hansen, Michael; Salado-Rasmussen, Kirsten

2016-01-01

OBJECTIVE: Cardiovascular implantable electronic device (CIED) infections are increasing in numbers. The objective was to review the clinical presentation and outcome in patients affected with CIED infections with either local pocket or systemic presentation. DESIGN: All device removals due to CIED......-up no relapses and two cases of new infections were noted (2.8%). CONCLUSIONS: CIED infection with systemic or pocket infection was difficult to distinguish in clinical presentation and outcome. Complete device removal and antibiotic treatment of long duration was safe and without relapses....

Rotavirus infection

Science.gov (United States)

Crawford, Sue E.; Ramani, Sasirekha; Tate, Jacqueline E.; Parashar, Umesh D.; Svensson, Lennart; Hagbom, Marie; Franco, Manuel A.; Greenberg, Harry B.; O’Ryan, Miguel; Kang, Gagandeep; Desselberger, Ulrich; Estes, Mary K.

2017-01-01

Rotavirus infections are a leading cause of severe, dehydrating gastroenteritis in children rotavirus over a decade ago, rotavirus infections still result in >200,000 deaths annually, mostly in low-income countries. Rotavirus primarily infects enterocytes and induces diarrhoea through the destruction of absorptive enterocytes (leading to malabsorption), intestinal secretion stimulated by rotavirus non-structural protein 4 and activation of the enteric nervous system. In addition, rotavirus infections can lead to antigenaemia (which is associated with more severe manifestations of acute gastroenteritis) and viraemia, and rotavirus can replicate in systemic sites, although this is limited. Reinfections with rotavirus are common throughout life, although the disease severity is reduced with repeat infections. The immune correlates of protection against rotavirus reinfection and recovery from infection are poorly understood, although rotavirus-specific immunoglobulin A has a role in both aspects. The management of rotavirus infection focuses on the prevention and treatment of dehydration, although the use of antiviral and anti-emetic drugs can be indicated in some cases. PMID:29119972

INFECTIOUS DISEASE RISKS IN THE TRANSMIGRATION AREA, WAY ABUNG III, LAMPUNG PROVINCE

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S. Gandahusada

2012-09-01

Full Text Available Telah dilakukan pemeriksaan secara laboratoris terhadap kesehatan transmigran yang berasal dari Jawa sebelum (1976 dan kurang lebih 2 tahun (1978 sesudah mereka menempati daerah transmigrasi Way Abung III, Lampung. Tujuan pemeriksaan ini adalah untuk mengetahui penyakit-penyakit yang mengancam mereka di daerah barunya. Pemeriksaan telah dilakukan terhadap sediaan darah yaitu untuk mengetahui adanya parasit malaria dan mikrofilaria, sedangkan pemeriksaan serologis untuk mengetahui adanya infeksi arbovirus, scrub dan murine typhus. Pemeriksaan tinja dilakukan hanya pada tahun 1976 untuk mengetahui adanya parasit usus. Dari hasil pemeriksaan tadi ditemukan bahwa prevalensi malaria meningkat dari 0,2% (1976 menjadi 10% (1978, sedangkan mikrofilaria rate sebelum dan sesudah pemindahan tetap 0. Hasil pemeriksaan tinja terhadap transmigran sebelum tiba di Lampung menunjukkan prevalensi Ascaris lumbricoides, Trichuris trichiura dan cacing tambang berturut-turut sebesar 46%,, 28%, dan 80%. Serologis hemagglutination inhibition (HI antibody positive terhadap Japanese encephalitis (JE virus naik dari 43,3%, menjadi 74,2%, sedangkan prevalensi HI antibody positive terhadap chikungunya (CHIK virus tetap sama yaitu 3,5% sebelum dan 2,9% sesudah pemindahan. Prevalensi positif fluores-cent antibody test(FAT terhadap scrub dan murine typhus juga tidak ada perubahan yaitu 4,0% sebelum dan 3,4% sesudah pemindahan untuk scrub typhus dan 13,7%, sebelum dan 13,8% sesudah pemindahan untuk murine typhus. Dari hewan-hewan yang terdapat di Way Abung IH, serologis positif HI antibody kambing mempunyai prevalensi tertinggi (3% terhadap arbovirus Group A (alpha virus dan sapi ter­tinggi (35% terhadap arbovirus Group B (flavivirus. Vektor-vektor potensial malaria, filariasis, scrub dan murine typhus, dan arbovirus infeksi dapat dijumpai di daerah transmigrasi Way Abung III, Lam­pung. Kecuali malaria ditarik kesimpulan bahwa diperlukan paired data untuk prevalensi cacing

Risk factors for Clostridium difficile infection in HIV-infected patients.

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Imlay, Hannah; Kaul, Daniel; Rao, Krishna

2016-01-01

Clostridium difficile infection is a healthcare-associated infection resulting in significant morbidity. Although immunosuppression is associated with Clostridium difficile infection acquisition and adverse outcomes, the epidemiology of Clostridium difficile infection in HIV-infected patients has been little studied in the era of antiretroviral therapy. This study identifies the risk factors for acquisition of Clostridium difficile infection in HIV-infected patients. A retrospective, propensity score-matched case-control study design was employed, with patients selected from our institution's outpatient HIV clinic. Clostridium difficile infection cases were defined as having positive stool testing plus an appropriate clinical presentation. The propensity score was generated via multiple logistic regression from year of HIV diagnosis, age at first contact, duration of follow-up, gender, and initial CD4 count. The 46 cases included were matched to a total of 180 controls. Prior antibiotic treatment was a significant predictor of Clostridium difficile infection (odds ratio: 13, 95% confidence interval: 3.49-48.8, p  Clostridium difficile infection in the multivariable model (odds ratio: 15.17, confidence interval: 1.31-175.9, p  = .021). As in the general population, frequent hospitalizations and exposure to antimicrobials are independent predictors of Clostridium difficile infection acquisition in patients with HIV. Additionally, low CD4 count and proton pump inhibitor use are new potentially modifiable variables that can be targeted for prevention of Clostridium difficile infection in future interventional studies.

Pinworm Infection

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Pinworm infection Overview Pinworm infection is the most common type of intestinal worm infection in the United States and one of the most common worldwide. Pinworms are thin and white, measuring about 1/4 ...

Congenital Cytomegalovirus Infection After Recurrent Maternal Infection: Report of a Case

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Özgür Olukman

2005-06-01

Full Text Available Cytomegalovirus (CMV is a double- stranded DNA virus in the Herpesvirus family, and it is a common cause of congenital viral infections. Congenital CMV infection is transmitted from the mother with viremia to the fetus via the placenta. Disease may result from a primary or recurrent maternal infection but the former is a common cause of severe disease. The risk for fetal infection is grater in primary maternal infection. We report a newborn infant with symptomatic congenital CMV infection associated with\trecurrent maternal infection.

Necrotizing soft tissue infections - a multicentre, prospective observational study (INFECT)

NARCIS (Netherlands)

Madsen, M.B.; Skrede, S.; Bruun, T.; Arnell, P.; Rosén, A.; Nekludov, M.; Karlsson, Y.; Bergey, F.; Saccenti, E.; Martins dos Santos, V.A.P.; Perner, A.; Norrby-Teglund, A.; Hyldegaard, O.

2018-01-01

Background: The INFECT project aims to advance our understanding of the pathophysiological mechanisms in necrotizing soft tissue infections (NSTIs). The INFECT observational study is part of the INFECT project with the aim of studying the clinical profile of patients with NSTIs and correlating

Shigella Infections

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Shigella Infections KidsHealth / For Parents / Shigella Infections What's in ... Doctor Print en español Infecciones por Shigella About Shigella Shigella are bacteria that can infect the digestive ...

Nematode Infections Are Risk Factors for Staphylococcal Infection in Children

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Sandra F Moreira-Silva

2002-04-01

Full Text Available Nematode infection may be a risk factor for pyogenic liver abscess in children and we hypothesized that the immunomodulation induced by those parasites would be a risk factor for any staphylococcal infection in children. The present study was designed to compare, within the same hospital, the frequency of intestinal nematodes and Toxocara infection in children with and without staphylococcal infections. From October 1997 to February 1998, 80 children with staphylococcal infection and 110 children with other diseases were submitted to fecal examination, serology for Toxocara sp., evaluation of plasma immunoglobulin levels, and eosinophil counts. Mean age, gender distribution, birthplace, and socioeconomic conditions did not differ significantly between the two groups. Frequency of intestinal nematodes and positive serology for Toxocara, were remarkably higher in children with staphylococcal infections than in the non-staphylococcal group. There was a significant correlation between intestinal nematodes or Toxocara infection and staphylococcal infection in children, reinforced by higher eosinophil counts and higher IgE levels in these children than in the control group. One possible explanation for this association would be the enhancement of bacterial infection by the immunomodulation induced by helminth infections, due to strong activation of the Th2 subset of lymphocytes by antigens from larvae and adult worms.

Fish tapeworm infection

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Fish tapeworm infection is an intestinal infection with a parasite found in fish. ... The fish tapeworm ( Diphyllobothrium latum ) is the largest parasite that infects humans. Humans become infected when they eat raw ...

Genomics-enabled sensor platform for rapid detection of viruses related to disease outbreak.

Energy Technology Data Exchange (ETDEWEB)

Brozik, Susan M; Manginell, Ronald P; Moorman, Matthew W; Xiao, Xiaoyin; Edwards, Thayne L.; Anderson, John Moses; Pfeifer, Kent Bryant; Branch, Darren W.; Wheeler, David Roger; Polsky, Ronen; Lopez, DeAnna M.; Ebel, Gregory D.; Prasad, Abhishek N.; Brozik, James A.; Rudolph, Angela R.; Wong, Lillian P.

2013-09-01

Bioweapons and emerging infectious diseases pose growing threats to our national security. Both natural disease outbreak and outbreaks due to a bioterrorist attack are a challenge to detect, taking days after the outbreak to identify since most outbreaks are only recognized through reportable diseases by health departments and reports of unusual diseases by clinicians. In recent decades, arthropod-borne viruses (arboviruses) have emerged as some of the most significant threats to human health. They emerge, often unexpectedly, from cryptic transmission foci causing localized outbreaks that can rapidly spread to multiple continents due to increased human travel and trade. Currently, diagnosis of acute infections requires amplification of viral nucleic acids, which can be costly, highly specific, technically challenging and time consuming. No diagnostic devices suitable for use at the bedside or in an outbreak setting currently exist. The original goals of this project were to 1) develop two highly sensitive and specific diagnostic assays for detecting RNA from a wide range of arboviruses; one based on an electrochemical approach and the other a fluorescent based assay and 2) develop prototype microfluidic diagnostic platforms for preclinical and field testing that utilize the assays developed in goal 1. We generated and characterized suitable primers for West Nile Virus RNA detection. Both optical and electrochemical transduction technologies were developed for DNA-RNA hybridization detection and were implemented in microfluidic diagnostic sensing platforms that were developed in this project.

Medical Entomology Project.

Science.gov (United States)

1983-01-01

placed on examples from the Africanus Subgroup as they are important vectors of Yellow Fever, Rift Valley Fever, Chickungunya and Zika viruses . Currently...Mosquitoes Neo tropical Malaria Anophe lea Culicidae Asia Arbovirus diseases Culex Vectors Africa Biosystematics Aedes 2 ABSTRACT AmA ME iMW0 6 N 0meormp...Research continues on the arbovirus vector groups of the subgenus Stegomqj, genus Aedes , of the African Region. 4.. N7 "’Vic ° ’. ,tlt Cobes ;D i SECURITY

Development and Validation of a Serologic Test Panel for Detection of Powassan Virus Infection in U.S. Patients Residing in Regions Where Lyme Disease Is Endemic.

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Thomm, Angela M; Schotthoefer, Anna M; Dupuis, Alan P; Kramer, Laura D; Frost, Holly M; Fritsche, Thomas R; Harrington, Yvette A; Knox, Konstance K; Kehl, Sue C

2018-01-01

Powassan virus (POWV) is an emerging tick-borne arbovirus presenting a public health threat in North America. POWV lineage II, also known as deer tick virus, is the strain of the virus most frequently found in Ixodes scapularis ticks and is implicated in most cases of POWV encephalitis in the United States. Currently, no commercial tests are available to detect POWV exposure in tick-borne disease (TBD) patients. We describe here the development and analytical validation of a serologic test panel to detect POWV infections. The panel uses an indirect enzyme immunoassay (EIA) to screen. EIA-positive samples reflex to a laboratory-developed, POWV-specific immunofluorescence assay (IFA). The analytical sensitivity of the test panel was 89%, and the limit of detection was a plaque reduction neutralization test (PRNT) titer of 1:20. The analytical specificity was 100% for the IgM assay and 65% for the IgG assay when heterologous-flavivirus-positive samples were tested. On samples collected from regions where Lyme disease is endemic, seroprevalence for POWV in TBD samples was 9.4% (10 of 106) versus 2% when tested with non-TBD samples (2 of 100, P = 0.034). No evidence of POWV infection was seen in samples collected from a region where Lyme disease was not endemic (0 of 22). This test panel provides a sensitive and specific platform for detecting a serologic response to POWV early in the course of infection when neutralizing antibodies may not be detectable. Combined with clinical history, the panel is an effective tool for identifying acute POWV infection. IMPORTANCE Approximately 100 cases of POWV disease were reported in the United States over the past 10 years. Most cases have occurred in the Northeast (52) and Great Lakes (45) regions (https://www.cdc.gov/powassan/statistics.html). The prevalence of POWV in ticks and mammals is increasing, and POWV poses an increasing threat in a greater geographical range. In areas of the Northeast and Midwest where Lyme disease is

[Infected knee prostheses. Part 2: chronic late infections].

Science.gov (United States)

Herrmann, P; Thoele, P; Heppert, V

2013-06-01

Treatment of late and chronic infections, which require the replacement of all the infected implant material. All infections lasting more than 4 weeks that have been proven to be bacterial and/or obvious signs of infection. Unsuitable for anesthesia, high acute infection with sepsis and risk for bacteremia with danger to life, large soft tissue damage where plastic surgery coverage is not possible. Arthrotomy, synovectomy, removal of all foreign bodies including all residue of polymethylmethacrylate (PMMA), jet lavage, spacer, drainage, wound closure or temporary closure using vacuum sealing. Bed rest with a leg brace and drainage until daily drainage volume is exchange of the spacer. In the literature, the success rate for both the one-stage or the two-stage procedure is about 80-95%. In our very nonhomogeneous collective the overall rate of success is about 81%.

Infection After Hysterectomy

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David L. Hemsell

1997-01-01

Full Text Available Antibiotic prophylaxis and advances in technology have reduced operative site infections after hysterectomy to a minimum. Pelvic infections are the most common infection type and respond promptly to a variety of parenteral single-agent and combination antibiotic regimens. Oral antibiotic regimens following parenteral therapy are unnecessary. Abdominal incision infections are less common than pelvic infections, less common than seromas or hematomas, and usually do not require antimicrobial therapy. Abscesses or infected hematomas require parenteral antimicrobial therapy, and drainage of those located above the cuff will predictably shorten therapy time. With early discharge from the hospital, many infections will not become evident until after the patient is home. For that reason, it is important that the patient's discharge instructions outline symptoms and signs associated with these infections so she can present for care at the earliest possible time.

Cacipacore virus as an emergent mosquito-borne Flavivirus

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Mario Luis Garcia de Figueiredo

Full Text Available Abstract INTRODUCTION: Cacipacore virus (CPCV, a possible bird-associated flavivirus, has yet to be detected in mosquitoes. Our purpose is examining CPCV in mosquitoes from the Amazon region of Brazil. METHODS: Approximately 3,253 Culicidae (grouped into 264 pools were collected from the Amazon region during 2002-2006 and analyzed using a Flavivirus genus-specific reverse transcription- polymerase chain reaction followed by nested polymerase chain reaction assay and by nucleotide sequencing of amplicons. RESULTS: Nucleotide sequences from five mosquito samples showed high similarity to the those of CPCV originally isolated in the Amazon region. CONCLUSIONS: This is the first report of CPCV-infected mosquitoes which has implications on the arbovirus maintenance in nature and transmission to man.

Pseudomonal breast infection

Science.gov (United States)

Rastall, S; Catchpole, C; Bright-Thomas, R; Thrush, S

2010-01-01

Breast infection and breast sepsis secondary to Pseudomonas aeruginosa is uncommon. We report two cases of pseudomonal breast infection leading to septic shock and abscess formation in women with non-responding breast infection. The management of breast infection is broad-spectrum antibiotics and ultrasound with aspiration of any collection. To treat breast infection effectively, the causative organism must be isolated to enable appropriate antibiotic therapy. PMID:20412664

[Arboviroses in the region of Nosy-Bé, Madagascar. Serologic and entomologic data].

Science.gov (United States)

Fontenille, D; Mathiot, C; Rodhain, F; Coulanges, P

1988-01-01

Since 1977, the Pasteur Institute of Madagascar has been studying, during six surveys, the arboviruses of Nosy-Be area, in the north-west of Madagascar. 47.2% out of 271 human sera and 11.3% out of 151 sera of Lemurs, tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. The results show an important prevalence of Flaviviruses. West Nile and Dengue 1 viruses were probably circulating some years before the surveys. Antibodies against Sindbis and Rift Valley Fever viruses, were found only in few subjects. Bunyamwera and California groups of virus are absent. The rate of positive Lemurs is weak, particularly in Lemur macaco macaco. Flaviviruses are the most frequent. 12,262 haematophagous diptera (11,965 Culicidae belonging to 40 species) were caught. Aedes aegypti and Aedes albopictus are both present. Arbovirus isolation attempts from 394 mosquito pools failed; only Mengo virus was isolated from four pools of Eretmapodites quinquevittatus and one pool of Aedes (Skusea) sp.

Primary Human Placental Trophoblasts are Permissive for Zika Virus (ZIKV) Replication.

Science.gov (United States)

Aagaard, Kjersti M; Lahon, Anismrita; Suter, Melissa A; Arya, Ravi P; Seferovic, Maxim D; Vogt, Megan B; Hu, Min; Stossi, Fabio; Mancini, Michael A; Harris, R Alan; Kahr, Maike; Eppes, Catherine; Rac, Martha; Belfort, Michael A; Park, Chun Shik; Lacorazza, Daniel; Rico-Hesse, Rebecca

2017-01-27

Zika virus (ZIKV) is an emerging mosquito-borne (Aedes genus) arbovirus of the Flaviviridae family. Although ZIKV has been predominately associated with a mild or asymptomatic dengue-like disease, its appearance in the Americas has been accompanied by a multi-fold increase in reported incidence of fetal microcephaly and brain malformations. The source and mode of vertical transmission from mother to fetus is presumptively transplacental, although a causal link explaining the interval delay between maternal symptoms and observed fetal malformations following infection has been missing. In this study, we show that primary human placental trophoblasts from non-exposed donors (n = 20) can be infected by primary passage ZIKV-FLR isolate, and uniquely allowed for ZIKV viral RNA replication when compared to dengue virus (DENV). Consistent with their being permissive for ZIKV infection, primary trophoblasts expressed multiple putative ZIKV cell entry receptors, and cellular function and differentiation were preserved. These findings suggest that ZIKV-FLR strain can replicate in human placental trophoblasts without host cell destruction, thereby serving as a likely permissive reservoir and portal of fetal transmission with risk of latent microcephaly and malformations.

In-silico screening for anti-Zika virus phytochemicals.

Science.gov (United States)

Byler, Kendall G; Ogungbe, Ifedayo Victor; Setzer, William N

2016-09-01

Zika virus (ZIKV) is an arbovirus that has infected hundreds of thousands of people and is a rapidly expanding epidemic across Central and South America. ZIKV infection has caused serious, albeit rare, complications including Guillain-Barré syndrome and congenital microcephaly. There are currently no vaccines or antiviral agents to treat or prevent ZIKV infection, but there are several ZIKV non-structural proteins that may serve as promising antiviral drug targets. In this work, we have carried out an in-silico search for potential anti-Zika viral agents from natural sources. We have generated ZIKV protease, methyltransferase, and RNA-dependent RNA polymerase using homology modeling techniques and we have carried out molecular docking analyses of our in-house virtual library of phytochemicals with these protein targets as well as with ZIKV helicase. Overall, 2263 plant-derived secondary metabolites have been docked. Of these, 43 compounds that have drug-like properties have exhibited remarkable docking profiles to one or more of the ZIKV protein targets, and several of these are found in relatively common herbal medicines, suggesting promise for natural and inexpensive antiviral therapy for this emerging tropical disease. Copyright © 2016 Elsevier Inc. All rights reserved.

SPHINGOMONAS PAUCIMOBILIS INFECTIONS IN CHILDREN: NOSOCOMIAL VERSUS COMMUNITY ACQUIRED INFECTIONS

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Nuri Bayram

2013-06-01

Full Text Available Sphingomonas paucimobilis is a causative agent of infection in immunocompromised patients, and healthcare-associated infections. Although the infections associated with S.paucimobilis occurs rarely, it has been encountered with increasing frequency in clinical settings. In the current study we noted the risk factors and clinical features of the children with S.paucimobilis infections, and the antimicrobial susceptibilities of the isolated strains among the patients. This study was conducted in Dr. Behçet Uz Children’s Hospital, Turkey, during the period of January 2005 and December 2012. The medical records of pediatric patients with positive cultures for S.paucimobilis were reviewed. Sphingomonas paucimobilis isolates were recovered from 24 pediatric patients. The median age was 4 years (ranging from 3 days infant to 15 years and 58,3% were male. Eight (33,3% of the patients were under 1 months of age. Among the patients; 13 (54,2% infections were community related however 11(45.8% infections were nosocomial infection. The median duration of hospital stay was 7 days (ranging from 4 to 22 days. The most effective antibiotics were fluoroquinolones, carbapenems, and trimethoprim/sulfamethoxazole. This is the first largest study in children to evaluate the clinical features of S. paucimobilis infections. Sphingomonas paucimobilis may cause infections in both previously healthy and immunocompromised children. Although variable antimicrobial regimens were achieved to the patients, there was no attributable fatality due to S.paucimobilis infections due to the low virulence of the bacteria.

Prosthetic Joint Infections

Science.gov (United States)

Aslam, Saima; Darouiche, Rabih O.

2012-01-01

Prosthetic joint infections represent a major therapeutic challenge for both healthcare providers and patients. This paper reviews the predisposing factors, pathogenesis, microbiology, diagnosis, treatment and prophylaxis of prosthetic joint infection. The most optimal management strategy should be identified based on a number of considerations including type and duration of infection, antimicrobial susceptibility of the infecting pathogen, condition of infected tissues and bone stock, patient wishes and functional status. PMID:22847032

Occurrence of avian Plasmodium and West Nile virus in culex species in Wisconsin

Science.gov (United States)

Hughes, T.; Irwin, P.; Hofmeister, E.; Paskewitz, S.M.

2010-01-01

The occurrence of multiple pathogens in mosquitoes and birds could affect the dynamics of disease transmission. We collected adult Culex pipiens and Cx. restuans (Cx. pipiens/restuans hereafter) from sites in Wisconsin and tested them for West Nile virus (WNV) and for avian malaria (Plasmodium). Gravid Cx. pipiens/restuans were tested for WNV using a commercial immunoassay, the RAMP?? WNV test, and positive results were verified by reverse transcriptasepolymerase chain reaction. There were 2 WNV-positive pools of Cx. pipiens/restuans in 2006 and 1 in 2007. Using a bias-corrected maximum likelihood estimation, the WNV infection rate for Cx. pipiens/restuans was 5.48/1,000 mosquitoes in 2006 and 1.08/1,000 mosquitoes in 2007. Gravid Cx. pipiens or Cx. restuans were tested individually for avian Plasmodium by a restriction enzymebased assay. Twelve mosquitoes were positive for avian Plasmodium (10.0), 2 were positive for Haemoproteus, and 3 were positive for Leucocytozoon. There were 4 mixed infections, with mosquitoes positive for >1 of the hemosporidian parasites. This work documents a high rate of hemosporidian infection in Culex spp. and illustrates the potential for co-infections with other arboviruses in bird-feeding mosquitoes and their avian hosts. In addition, hemosporidian infection rates may be a useful tool for investigating the ecological dynamics of Culex/avian interactions. ?? 2010 by The American Mosquito Control Association, Inc.

Nodal infection in Markovian susceptible-infected-susceptible and susceptible-infected-removed epidemics on networks are non-negatively correlated.

Science.gov (United States)

Cator, E; Van Mieghem, P

2014-05-01

By invoking the famous Fortuin, Kasteleyn, and Ginibre (FKG) inequality, we prove the conjecture that the correlation of infection at the same time between any pair of nodes in a network cannot be negative for (exact) Markovian susceptible-infected-susceptible (SIS) and susceptible-infected-removed (SIR) epidemics on networks. The truth of the conjecture establishes that the N-intertwined mean-field approximation (NIMFA) upper bounds the infection probability in any graph so that network design based on NIMFA always leads to safe protections against malware spread. However, when the infection or/and curing are not Poisson processes, the infection correlation between two nodes can be negative.

Nodal infection in Markovian susceptible-infected-susceptible and susceptible-infected-removed epidemics on networks are non-negatively correlated

Science.gov (United States)

Cator, E.; Van Mieghem, P.

2014-05-01

By invoking the famous Fortuin, Kasteleyn, and Ginibre (FKG) inequality, we prove the conjecture that the correlation of infection at the same time between any pair of nodes in a network cannot be negative for (exact) Markovian susceptible-infected-susceptible (SIS) and susceptible-infected-removed (SIR) epidemics on networks. The truth of the conjecture establishes that the N-intertwined mean-field approximation (NIMFA) upper bounds the infection probability in any graph so that network design based on NIMFA always leads to safe protections against malware spread. However, when the infection or/and curing are not Poisson processes, the infection correlation between two nodes can be negative.

Necrotizing soft tissue infections - a multicentre, prospective observational study (INFECT)

DEFF Research Database (Denmark)

Madsen, M. B.; Skrede, S.; Bruun, T.

2018-01-01

these to patient-important outcomes. With this protocol and statistical analysis plan we describe the methods used to obtain data and the details of the planned analyses. Methods: The INFECT study is a multicentre, prospective observational cohort study. Patients with NSTIs are enrolled in five Scandinavian......Background: The INFECT project aims to advance our understanding of the pathophysiological mechanisms in necrotizing soft tissue infections (NSTIs). The INFECT observational study is part of the INFECT project with the aim of studying the clinical profile of patients with NSTIs and correlating...

Retinitis due to opportunistic infections in Iranian HIV infected patients.

Directory of Open Access Journals (Sweden)

Ali Abdollahi

2013-10-01

Full Text Available We tried to evaluate prevalence and characteristics of Iranian HIV infected patients with retinitis due to opportunistic infections. In this cross sectional study, we evaluated 106 HIV infected patients via indirect ophthalmoscopy and slit lamp examination by 90 lens to find retinitis cases. General information and results of ophthalmologic examination were analyzed. Prevalence of retinitis due to opportunistic infections was 6.6%: cytomegalovirus (CMV retinitis 1.88%, toxoplasmosis retinochoroiditis 1.88% and tuberculosis chorioretinitis 2.83%. CD4 count was higher than 50 cell/µlit in both cases with CMV retinitis. Along with increasing survival in the HIV infected patients, the prevalence of complications such as ocular manifestation due to opportunistic infections are increasing and must be more considered.

The Burden of Dengue Fever and Chikungunya in Southern Coastal Ecuador: Epidemiology, Clinical Presentation, and Phylogenetics from the First Two Years of a Prospective Study

Science.gov (United States)

Stewart-Ibarra, Anna M.; Ryan, Sadie J.; Kenneson, Aileen; King, Christine A.; Abbott, Mark; Barbachano-Guerrero, Arturo; Beltrán-Ayala, Efraín; Borbor-Cordova, Mercy J.; Cárdenas, Washington B.; Cueva, Cinthya; Finkelstein, Julia L.; Lupone, Christina D.; Jarman, Richard G.; Maljkovic Berry, Irina; Mehta, Saurabh; Polhemus, Mark; Silva, Mercy; Endy, Timothy P.

2018-01-01

Abstract. Here, we report the findings from the first 2 years (2014–2015) of an arbovirus surveillance study conducted in Machala, Ecuador, a dengue-endemic region. Patients with suspected dengue virus (DENV) infections (index cases, N = 324) were referred from five Ministry of Health clinical sites. A subset of DENV-positive index cases (N = 44) were selected, and individuals from the index household and four neighboring homes within 200 m were recruited (N = 400). Individuals who entered the study, other than the index cases, are referred to as associates. In 2014, 70.9% of index cases and 35.6% of associates had acute or recent DENV infections. In 2015, 28.3% of index cases and 12.8% of associates had acute or recent DENV infections. For every DENV infection captured by passive surveillance, we detected an additional three acute or recent DENV infections in associates. Of associates with acute DENV infections, 68% reported dengue-like symptoms, with the highest prevalence of symptomatic acute infections in children aged less than 10 years. The first chikungunya virus (CHIKV) infections were detected on epidemiological week 12 in 2015; 43.1% of index cases and 3.5% of associates had acute CHIKV infections. No Zika virus infections were detected. Phylogenetic analyses of isolates of DENV from 2014 revealed genetic relatedness and shared ancestry of DENV1, DENV2, and DENV4 genomes from Ecuador with those from Venezuela and Colombia, indicating the presence of viral flow between Ecuador and surrounding countries. Enhanced surveillance studies, such as this, provide high-resolution data on symptomatic and inapparent infections across the population. PMID:29512482

FEVER AS INDICATOR TO SECONDARY INFECTION IN DENGUE VIRAL INFECTION

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Soegeng Soegijanto

2018-04-01

Full Text Available Dengue Virus Infections are distributed in tropical and sub-tropical regions and transmitted by the mosquitoes such as Aedes aegypti and Aedes albopictus. Dengue virus can cause dengue fever, dengue hemorrhagic fever and dengue shock syndrome or dengue and severe dengue classified by World Health Organization. Beside it concurrent infection virus salmonella had been found some cases who showed fever more than 7 days. Concurrent infection with two agents can result in an illness having overlapping symptoms creating a diagnostic dilemma for treating physician, such as dengue fever with typhoid fever. The aim of this research is detection of dengue virus and secondary infection with Salmonella typhi in patients suspected dengue virus infection. Detection of dengue virus and Salmonella typhi using immunochromatography test such as NS1, IgG/IgM for dengue virus infection, and IgM/IgG Salmonella and blood culture. The fifty children with dengue virus infection came to Soerya hospital and 17 cases suspected dengue virus infection, five cases showed a positive NS1 on the second day of fever and one case concurrent with clinical manifestation of convulsi on the third days of fever there were five cases only showed positive. It was showed in this study that on the fourth to six day of fever in dengue virus infection accompanied by antibody IgM & IgG dengue. There were 12 cases showed the clinical manifestation of concurrent dengue viral infection and Salmonella, all of them showed a mild clinical manifestation and did not show plasma leakage and shock. In this study we found the length of stay of concurrent Dengue Virus Infection and Salmonella infection is more than 10 days. These patients were also more likely to have co-existing haemodynamic disturbances and bacterial septicaemia which would have required treatment with inotropes and antibiotics. This idea is very important to make update dengue viral management to decrease mortality in outbreak try to

Urbanization is a main driver for the larval ecology of Aedes mosquitoes in arbovirus-endemic settings in south-eastern Côte d'Ivoire.

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Zahouli, Julien B Z; Koudou, Benjamin G; Müller, Pie; Malone, David; Tano, Yao; Utzinger, Jürg

2017-07-01

Culex tigripes was commonly sampled, while Toxorhynchites and Eretmapodites were mostly collected in rural areas. In Côte d'Ivoire, urbanization is associated with high abundance of Aedes larvae and a predominance of artificial containers as breeding sites, mostly colonized by Ae. aegypti in urban areas. Natural containers are still common in rural areas harboring several Aedes species and, therefore, limiting the impact of systematic removal of discarded containers on the control of arbovirus diseases.

[Reactivation of parvovirus B19 infection in an HIV-infected woman].

Science.gov (United States)

Sterpu, R; Ichou, H; Mahé, I; Mortier, E

2014-06-01

Infection by human parvovirus B19 (erythrovirus B19) is common and usually asymptomatic during childhood conferring lasting protection against a new infection. Parvovirus B19 infection may cause erythema infectiosum (5th disease) and aplastic crisis. Secondary symptomatic parvovirus B19 infection in the same patient is rare and its physiopathology is not always clear. A 48-year-old HIV-infected female patient presented within 5 years two acute episodes of parvovirus B19 infection although her CD4 cells count was above 500/mm(3). Absence of specific antibodies production after the first episode and persisting parvovirus viremia suggested viral reactivation rather than re-infection. During the second episode, specific antibodies were produced. Similarly to most DNA viruses, parvovirus B19 reactivation is possible in HIV-infected patients while effectively treated by antiretroviral therapy. Copyright © 2013 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Urinary Tract Infection (UTI)

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... Home A-Z Health Topics Urinary tract infections Urinary tract infections > A-Z Health Topics Urinary tract infections (PDF, ... Embed Subscribe To receive Publications email updates Submit Urinary tract infections Urinary tract infections (UTIs) are most often caused ...

Congenital cytomegalovirus infection

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Katarina Rednak-Paradiž

2006-11-01

Full Text Available Background: CMV is the most common agent that causes congenital virus infection. Only 10 % of infected children have symptomatic infection immediately after birth. Signs of central nervous system damage, neurosensory deafness and delayed psychomotor development may manifest as a result of asimptomatic congenital infection later in childhood. In the article we present basic properties of CMV; we describe clinical picture of the congenital infection and possibilities of diagnose and its treatment. We present five children with symptomatic congenital CMV infection that were hospitalized for the period 1992–2002 at the Neonatal department in the University Children’s Hospital in Ljubljana.Conclusions: Identification of infected neonates, especially those with asimptomatic congenital CMV infection, is difficult. Latest incidence of infection in Slovenia is unknown. With new investigations the efficiency of antiviral therapy was discovered but exact indications for therapy are not yet known. CMV vaccine, once available, may ultimately be the best control strategy for this important public health problem. Proper educating women in childbearing age about the risks of CMV and how to avoid disease transmission during pregnancy (hand washing, avoiding mouth-to-mouth contact with preschool children, usage of gloves especially when handling dipers or respiratory secretions are the only control strategies available.

[Infections of the oral mucosa II. Bacterial, mycotic and viral infections].

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Reichart, P A

1999-11-01

Non-specific infections of the oral mucosa are rare; however, they may present during HIV infection in the form of gingivo-periodontal lesions. In some of these Candida albicans may play a role in the pathogenesis. Sexually transmitted bacterial infections such as gonorrhoea and syphilis are frequently associated with HIV infection. Since penicillin resistance is frequent in gonorrhoea, the cephalosporines are mainly used for treatment. Syphilis increases the risk for transmission of HIV. Lues maligna with oral manifestations has been described. For this, penicillin G is the therapy of choice. Tuberculosis, characterized by multitherapy resistance, is associated with HIV infections world-wide; oral manifestations are rare. Oral candidiasis during HIV infection is often characterized by therapy resistance against fluconazole and a shift in species, with Candida glabrata and Candida krusei as the emerging species. The azoles are still the mainstay of therapy, particularly fluconazole. Herpes simplex (HSV) infections run an atypical course during HIV disease; resistance against acyclovir is a clinical problem. The association of HSV infection with erythema exudativum multiforme has been clearly shown. Oral hairy leukoplakia caused by Epstein Barr virus is a characteristic infection during immunosuppression. Cytomegalovirus infection is also observed in immunodeficient patients. Cases of ganciclovir resistance have been described. Human herpes virus 8 (HHV 8) is associated with Kaposi's sarcoma. Therapeutic trials have focussed on the inhibition of HHV 8 replication. Over 100 different genotypes of human papillomaviruses are known; some can cause infections of the oral mucosa. Characteristic lesions caused by different HPV genotypes are verruca vulgaris, condyloma acuminatum and focal epithelial hyperplasia.

Prosthetic vascular graft infection and prosthetic joint infection caused by Pseudomonas stutzeri.

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Bonares, Michael J; Vaisman, Alon; Sharkawy, Abdu

2016-01-01

Pseudomonas stutzeri is infrequently isolated from clinical specimens, and if isolated, more likely represents colonization or contamination rather than infection. Despite this, there are dozens of case reports which describe clinically significant P. stutzeri infections at variable sites. A 69-year-old man had a P. stutzeri infection of a prosthetic vascular graft infection, which he received in Panama City. He was successfully treated with a single antipseudomonal agent for 6 weeks and the removal of the infected vascular graft. A 70-year-old man had a P. stutzeri infection of a prosthetic joint, which was successfully treated with a single anti-pseudomonal agent for 6 weeks. There is only one other documented case of a prosthetic vascular graft infection secondary to P. stutzeri . There are 5 documented cases of P. stutzeri prosthetic joint infections. The previous cases were treated with antibiotics and variably, source control with the removal of prosthetic material. Most cases of P. stutzeri infection are due to exposure in health care settings. Immunocompromised states such as HIV or hematological and solid tumor malignancies are risk factors for P. stutzeri infection. Infections caused by P. stutzeri are far less frequent and less fatal than those caused by P. aeruginosa. The etiology of a P. stutzeri infection could be exposure to soil and water, but also contaminated material in the health care setting or an immunocompromised state. Iatrogenic infections that are secondary to health care tourism are a potential cause of fever in the returned traveler.

Host-feeding patterns of Aedes albopictus (Diptera: Culicidae) in relation to availability of human and domestic animals in suburban landscapes of central North Carolina.

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Richards, Stephanie L; Ponnusamy, Loganathan; Unnasch, Thomas R; Hassan, Hassan K; Apperson, Charles S

2006-05-01

eight (20%) were multiple bloodmeals taken from more than one human host. We conclude that the blood-feeding preference of Ae. albopictus for mammals will limit acquisition of arboviruses by this species from infected avian amplification hosts. This feeding preference likely limits the vector potential of Ae. albopictus for North American arboviruses.

Screening for potential anti-infective agents towards Burkholderia pseudomallei infection

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Eng, Su Anne; Nathan, Sheila

2014-09-01

The established treatment for melioidosis is antibiotic therapy. However, a constant threat to this form of treatment is resistance development of the causative agent, Burkholderia pseudomallei, towards antibiotics. One option to circumvent this threat of antibiotic resistance is to search for new alternative anti-infectives which target the host innate immune system and/or bacterial virulence. In this study, 29 synthetic compounds were evaluated for their potential to increase the lifespan of an infected host. The nematode Caenorhabditis elegans was adopted as the infection model as its innate immune pathways are homologous to humans. Screens were performed in a liquid-based survival assay containing infected worms exposed to individual compounds and survival of untreated and compound-treated worms were compared. A primary screen identified nine synthetic compounds that extended the lifespan of B. pseudomallei-infected worms. Subsequently, a disc diffusion test was performed on these selected compounds to delineate compounds into those that enhanced the survival of worms via antimicrobial activity i.e. reducing the number of infecting bacteria, or into those that did not target pathogen viability. Out of the nine hits selected, two demonstrated antimicrobial effects on B. pseudomallei. Therefore, the findings from this study suggest that the other seven identified compounds are potential anti-infectives which could protect a host against B. pseudomallei infection without developing the risk of drug resistance.

Arcanobacterium Haemolyticum Infections

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... Head Neck & Nervous System Heart Infections Learning Disabilities Obesity ... ) haemolyticum is an organism that most often causes infections and illnesses in teenagers and young adults. The infection is spread from person to person, ...

Infections are a global issue: infection addresses global issues.

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Grobusch, M P; Calleri, G; Bogner, J R

2012-12-01

Infections are of unifying global concern, despite regional differences in disease epidemiology, clinical appearance and the instruments to tackle them. The primary aim of Infection is "to be a forum for the presentation and discussion of clinically relevant information on infectious diseases… from all over the world". To that end, and as a reflection of the global burden of infectious diseases, we intend to increase the number of high-quality contributions from authors addressing the aetiology, pathogenesis, diagnosis and treatment of infectious diseases from outside Europe and the affluent North (Chang et al. Infection 40:359-365, 2012; Misra et al. Infection 40:125-130, 2012). The Editorial Board of Infection envisages the journal as an interface between where infectious diseases meet and mix between "North and South"--i.e., the field of travel medicine--frequently functioning as a sentinel for altered/novel disease activities that are encountered as imported conditions. With the change in generation on the Editorial Board, Infection aims to expand the areas of tropical medicine, travel medicine and global health with its own section editors (GC and MPG). Contributions from outside Europe are actively encouraged.

Puerperal infections.

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Eschenbach, D A; Wager, G P

1980-12-01

This comprehensive review on puerperal infections covers risk factors, causative bacteria, pathophysiology, diagnosis, therapy of specific entities, and prevention. Puerperal infection is problematic to define especially with antibiotics that change the course of fever. I may present as endometritis (most common), myometritis, parametritis, pelvic abscess, salpingitis, septic pelvic thrombophlebitis or septicemia, and also includes infections of the urinary tract, episiotomy, surgical wounds, lacerations or breast. Each of these is discussed in terms of contributing factors, microbiology, clinical findings, diagnosis, treatment, prevention and complications. Risk factors in general are cesarean section, premature rupture of the membranes, internal fetal monitoring, general anesthesia, pelvic examinations. The most common bacterial involved are group B and other streptococci, E. coli, Gardnerella vaginalis, Gram positive anaerobic cocci, Mycoplasma and pre-existing Chlamydial infections. Diagnosis of the causative organism is difficult because of polyinfection and difficulty of getting a sterile endometrial swab. Diagnosis of the infection is equally difficult because of the wide variety of symptoms: fever, abnormal lochia, tachycardia, tenderness, mass and abnormal bowel sounds are common. Therapy depends of the responsible microorganism, although 3 empirical tactics are suggested while awaiting results of culture: 1) choose an antibiotic for the most common aerobic bacteria; 2) an antibiotic effective against B. fragilis and one for aerobic bacteria, e.g. clindamycin and an aminoglycoside; 3) a nontoxic antibiotic active against most aerobic and anaerobic organisms, e.g. doxycycline or cefoxitin. An example of an infection recently described is pudendal-paracervical block infection, often signaled by severe hip pain. It is associated with vaginal bacteria, is usually complicated by abscess even with antibiotic coverage, and may end in paraplegia or fatal sepsis

Ranking of Nodal Infection Probability in Susceptible-Infected-Susceptible Epidemic

NARCIS (Netherlands)

Qu, B.; Li, C.; Van Mieghem, P.F.A.; Wang, H.

2017-01-01

The prevalence, which is the average fraction of infected nodes, has been studied to evaluate the robustness of a network subject to the spread of epidemics. We explore the vulnerability (infection probability) of each node in the metastable state with a given effective infection rate τ.

Cytomegalovirus infection in pregnancy.

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Kagan, Karl Oliver; Hamprecht, Klaus

2017-07-01

Due to the severe risk of long-term sequelae, prenatal cytomegalovirus infection is of particular importance amongst intrauterine viral infections. This review summarizes the current knowledge about CMV infection in pregnancy. A search of the Medline and Embase database was done for articles about CMV infection in pregnany. We performed a detailed review of the literature in view of diagnosis, epidemiology and management of CMV infection in pregnancy. The maternal course of the infection is predominantly asymptomatic; the infection often remains unrecognized until the actual fetal manifestation. Typical ultrasound signs that should arouse suspicion of intrauterine CMV infection can be distinguished into CNS signs such as ventriculomegaly or microcephaly and extracerebral infection signs such as hepatosplenomegaly or hyperechogenic bowel. Current treatment strategies focus on hygienic measures to prevent a maternal CMV infection during pregnancy, on maternal application of hyperimmunoglobulines to avoid materno-fetal transmission in case of a maternal seroconversion, and on an antiviral therapy in case the materno-fetal transmission have occurred. CMV infection in pregnancy may result in a severe developmental disorder of the newborn. This should be taken into account in the treatment of affected and non-affected pregnant women.

Infections and Pregnancy

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During pregnancy, some common infections like the common cold or a skin infection do not usually cause serious problems. ... of the infections that can be dangerous during pregnancy include Bacterial vaginosis (BV) Group B strep (GBS) ...

Immune responses induced by co-infection with Capillaria hepatica in Clonorchis sinensis-infected rats.

Science.gov (United States)

Moon, E-K; Lee, S-H; Goo, T W; Quan, F-S

2018-07-01

Clonorchis sinensis and Capillaria hepatica are zoonotic parasites that mainly infect the liver and cause serious liver disorders. However, immunological parameters induced by co-infection with these parasites remain unknown. In this study, for the first time, we investigated immunological profiles induced by co-infection with C. hepatica (CH) in C. sinensis (CS)-infected rats (Sprague-Dawley). Rats were infected primarily with 50 metacercariae of C. sinensis; 4 weeks later, they were subsequently infected with 1000 infective C. hepatica eggs. Significantly higher levels of C. sinensis- or C. hepatica-specific IgG antibodies were found in the sera of rats. Interestingly, no cross-reacting antibody was observed between C. sinensis and C. hepatica infections. Significantly raised eosinophil levels were found in the blood of C. sinensis/C. hepatica co-infected rats (CS + CH) compared to the blood of rats infected singly with C. sinensis. Co-infected rats showed significantly higher levels of lymphocyte proliferation and cytokine production compared to a single C. sinensis infection. The worm burden of C. sinensis was significantly reduced in co-infected rats compared to the single C. sinensis infection. These results indicate that the eosinophils, lymphocyte proliferation and cytokine production induced by subsequent infection with C. hepatica in C. sinensis-infected rats might contribute to the observed C. sinensis worm reduction.

A mouse model for Chikungunya: young age and inefficient type-I interferon signaling are risk factors for severe disease.

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Thérèse Couderc

2008-02-01

Full Text Available Chikungunya virus (CHIKV is a re-emerging arbovirus responsible for a massive outbreak currently afflicting the Indian Ocean region and India. Infection from CHIKV typically induces a mild disease in humans, characterized by fever, myalgia, arthralgia, and rash. Cases of severe CHIKV infection involving the central nervous system (CNS have recently been described in neonates as well as in adults with underlying conditions. The pathophysiology of CHIKV infection and the basis for disease severity are unknown. To address these critical issues, we have developed an animal model of CHIKV infection. We show here that whereas wild type (WT adult mice are resistant to CHIKV infection, WT mouse neonates are susceptible and neonatal disease severity is age-dependent. Adult mice with a partially (IFN-alpha/betaR(+/- or totally (IFN-alpha/betaR(-/- abrogated type-I IFN pathway develop a mild or severe infection, respectively. In mice with a mild infection, after a burst of viral replication in the liver, CHIKV primarily targets muscle, joint, and skin fibroblasts, a cell and tissue tropism similar to that observed in biopsy samples of CHIKV-infected humans. In case of severe infections, CHIKV also disseminates to other tissues including the CNS, where it specifically targets the choroid plexuses and the leptomeninges. Together, these data indicate that CHIKV-associated symptoms match viral tissue and cell tropisms, and demonstrate that the fibroblast is a predominant target cell of CHIKV. These data also identify the neonatal phase and inefficient type-I IFN signaling as risk factors for severe CHIKV-associated disease. The development of a permissive small animal model will expedite the testing of future vaccines and therapeutic candidates.

Prevention and treatment of surgical site infection in HIV-infected patients

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Zhang Lei

2012-05-01

Full Text Available Abstract Background Surgical site infection (SSI are the third most frequently reported nosocomial infection, and the most common on surgical wards. HIV-infected patients may increase the possibility of developing SSI after surgery. There are few reported date on incidence and the preventive measures of SSI in HIV-infected patients. This study was to determine the incidence and the associated risk factors for SSI in HIV-infected patients. And we also explored the preventive measures. Methods A retrospective study of SSI was conducted in 242 HIV-infected patients including 17 patients who combined with hemophilia from October 2008 to September 2011 in Shanghai Public Health Clinical Center. SSI were classified according to Centers for Disease Control and Prevention (CDC criteria and identified by bedside surveillance and post-discharge follow-up. Data were analyzed using SPSS 16.0 statistical software (SPSS Inc., Chicago, IL. Results The SSI incidence rate was 47.5% (115 of 242; 38.4% incisional SSIs, 5.4% deep incisional SSIs and 3.7% organ/space SSIs. The SSI incidence rate was 37.9% in HIV-infected patients undergoing abdominal operation. Patients undergoing abdominal surgery with lower preoperative CD4 counts were more likely to develop SSIs. The incidence increased from 2.6% in clean wounds to 100% in dirty wounds. In the HIV-infected patients combined with hemophilia, the mean preoperative albumin and postoperative hemoglobin were found significantly lower than those in no-SSIs group (P Conclusions SSI is frequent in HIV-infected patients. And suitable perioperative management may decrease the SSIs incidence rate of HIV-infected patients.

Cerebral infections

Energy Technology Data Exchange (ETDEWEB)

Karampekios, Spyros [University of Crete, Department of Radiology, Heraklion, Crete (Greece); Hesselink, John [UCSD, Department of Radiology, San Diego, CA (United States)

2005-03-01

Despite the development of many effective antibiotic therapies and the general improvement in hygiene and health care systems all over the world, the incidence of central nervous system (CNS) infection has increased significantly in the past 15 years. This can be attributed primarily to the acquired immunodeficiency syndrome (AIDS) epidemic and its devastating effect on the immune system and secondarily to various immunosuppressive agents that are being used in aggressive cancer treatment and in organ transplantations. The brain particularly is protected from infection by the calvarium, meninges and blood brain barrier. However, different types of pathogens, including bacteria, viruses, fungi and parasites, can reach the brain hematogenously or, less likely, by direct extension from an adjacent infected focus. The early detection and specific diagnosis of infection are of great importance, since brain infections are potentially treatable diseases. Imaging studies play a crucial role in the diagnostic process, along with the history (exposure to infectious agents), host factors (open head trauma, CSF leak, sinusitis, otitis, immune status), physical examination and laboratory analysis of CSF. (orig.)

Cerebral infections

International Nuclear Information System (INIS)

Karampekios, Spyros; Hesselink, John

2005-01-01

Despite the development of many effective antibiotic therapies and the general improvement in hygiene and health care systems all over the world, the incidence of central nervous system (CNS) infection has increased significantly in the past 15 years. This can be attributed primarily to the acquired immunodeficiency syndrome (AIDS) epidemic and its devastating effect on the immune system and secondarily to various immunosuppressive agents that are being used in aggressive cancer treatment and in organ transplantations. The brain particularly is protected from infection by the calvarium, meninges and blood brain barrier. However, different types of pathogens, including bacteria, viruses, fungi and parasites, can reach the brain hematogenously or, less likely, by direct extension from an adjacent infected focus. The early detection and specific diagnosis of infection are of great importance, since brain infections are potentially treatable diseases. Imaging studies play a crucial role in the diagnostic process, along with the history (exposure to infectious agents), host factors (open head trauma, CSF leak, sinusitis, otitis, immune status), physical examination and laboratory analysis of CSF. (orig.)

MRSA Infection

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... to spread and sometimes become life-threatening. MRSA infections may affect your: Bloodstream Lungs Heart Bones Joints Prevention Preventing HA-MRSA In the hospital, people who are infected or colonized with MRSA ...

Detection of prion infectivity in fat tissues of scrapie-infected mice.

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Brent Race

2008-12-01

Full Text Available Distribution of prion infectivity in organs and tissues is important in understanding prion disease pathogenesis and designing strategies to prevent prion infection in animals and humans. Transmission of prion disease from cattle to humans resulted in banning human consumption of ruminant nervous system and certain other tissues. In the present study, we surveyed tissue distribution of prion infectivity in mice with prion disease. We show for the first time detection of infectivity in white and brown fat. Since high amounts of ruminant fat are consumed by humans and also incorporated into animal feed, fat-containing tissues may pose a previously unappreciated hazard for spread of prion infection.

Infective endocarditis following urinary tract infection caused by Globicatella sanguinis

OpenAIRE

Takahashi, Saeko; Xu, Chieko; Sakai, Tetsuya; Fujii, Kotaro; Nakamura, Morio

2017-01-01

We report the first case of infective endocarditis following urinary tract infection (UTI) caused by Globicatella sanguinis in an 87-year-old Japanese woman with recurrent episodes of UTI. We identified the pathogen using the Rapid ID32 Strep system. Accurate identification of this infection is important and essential for the effective antimicrobial coverage to this pathogen.

Variation in Wolbachia effects on Aedes mosquitoes as a determinant of invasiveness and vectorial capacity.

Science.gov (United States)

King, Jessica G; Souto-Maior, Caetano; Sartori, Larissa M; Maciel-de-Freitas, Rafael; Gomes, M Gabriela M

2018-04-16

Wolbachia has been introduced into Aedes aegypti mosquitoes to control the spread of arboviruses, such as dengue, chikungunya and Zika. Studies showed that certain Wolbachia strains (such as wMel) reduce replication of dengue viruses in the laboratory, prompting the release of mosquitoes carrying the bacterium into the field, where vectorial capacity can be realistically assessed in relation to native non-carriers. Here we apply a new analysis to two published datasets, and show that wMel increases the mean and the variance in Ae. aegypti susceptibility to dengue infection when introgressed into Brazil and Vietnam genetic backgrounds. In the absence of other processes, higher mean susceptibility should lead to enhanced viral transmission. The increase in variance, however, widens the basis for selection imposed by unexplored natural forces, retaining the potential for reducing transmission overall.

Musculoskeletal infections: ultrasound appearances

Energy Technology Data Exchange (ETDEWEB)

Chau, C.L.F. [Department of Radiology, North District Hospital, NTEC, Fanling, NT, Hong Kong (China)]. E-mail: c8681@yahoo.com; Griffith, J.F. [Department of Diagnostic Radiology and Organ Imaging, Prince of Wales Hospital, NTEC, Shatin, NT, Hong Kong (China)

2005-02-01

Musculoskeletal infections are commonly encountered in clinical practice. This review will discuss the ultrasound appearances of a variety of musculoskeletal infections such as cellulitis, infective tenosynovitis, pyomyositis, soft-tissue abscesses, septic arthritis, acute and chronic osteomyelitis, and post-operative infection. The peculiar sonographic features of less common musculoskeletal infections, such as necrotizing fasciitis, and rice body formation in atypical mycobacterial tenosynovitis, and bursitis will also be presented.

Musculoskeletal infections: ultrasound appearances

International Nuclear Information System (INIS)

Chau, C.L.F.; Griffith, J.F.

2005-01-01

Musculoskeletal infections are commonly encountered in clinical practice. This review will discuss the ultrasound appearances of a variety of musculoskeletal infections such as cellulitis, infective tenosynovitis, pyomyositis, soft-tissue abscesses, septic arthritis, acute and chronic osteomyelitis, and post-operative infection. The peculiar sonographic features of less common musculoskeletal infections, such as necrotizing fasciitis, and rice body formation in atypical mycobacterial tenosynovitis, and bursitis will also be presented

Does Infection Site Matter? A Systematic Review of Infection Site Mortality in Sepsis.

Science.gov (United States)

Motzkus, Christine A; Luckmann, Roger

2017-09-01

Sepsis treatment protocols emphasize source control with empiric antibiotics and fluid resuscitation. Previous reviews have examined the impact of infection site and specific pathogens on mortality from sepsis; however, no recent review has addressed the infection site. This review focuses on the impact of infection site on hospital mortality among patients with sepsis. The PubMed database was searched for articles from 2001 to 2014. Studies were eligible if they included (1) one or more statistical models with hospital mortality as the outcome and considered infection site for inclusion in the model and (2) adult patients with sepsis, severe sepsis, or septic shock. Data abstracted included stage of sepsis, infection site, and raw and adjusted effect estimates. Nineteen studies were included. Infection sites most studied included respiratory (n = 19), abdominal (n = 19), genitourinary (n = 18), and skin and soft tissue infections (n = 11). Several studies found a statistically significant lower mortality risk for genitourinary infections on hospital mortality when compared to respiratory infections. Based on studies included in this review, the impact of infection site in patients with sepsis on hospital mortality could not be reliably estimated. Misclassification among infections and disease states remains a serious possibility in studies on this topic.

What Is Infective Endocarditis?

Science.gov (United States)

ANSWERS by heart Cardiovascular Conditions What Is Infective Endocarditis? Infective (bacterial) endocarditis (IE) is an infection of either the heart’s inner lining (endocardium) or the heart valves. Infective endocarditis is a serious — and sometimes fatal — illness. Two ...

Infective Endocarditis

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... Venous Thromboembolism Aortic Aneurysm More Infective Endocarditis Updated:Mar 29,2018 View an illustration of endocarditis Infective ... procedure. Web Booklets on Congenital Heart Defects These online publications describe many defects and the procedures used ...

Campylobacter Infections

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Campylobacter infection is a common foodborne illness. You usually get it from eating contaminated food, especially raw ... You can also get it from drinking contaminated water or raw milk, or handling infected animal feces ( ...

Staph Infections

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... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... infection. People with skin problems like burns or eczema may be more likely to get staph skin ...

Intestinal parasitic infections in HIV-infected patients, Lao People's Democratic Republic.

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Phimpha Paboriboune

Full Text Available BACKGROUND: HIV infection is an emerging problem in Laos. We conducted the first prospective study on intestinal parasites, including opportunistic protozoa, in newly diagnosed HIV infected patients, with or without diarrhea. The aims were to describe the spectrum of infections, to determine their prevalence and to assess their associations with diarrhea, CD4 cell count, place of residence and living conditions. METHODOLOGY: One to three stool samples over consecutive days were obtained from 137 patients. The Kato thick smear method, formalin-ethyl concentration and specific stains for coccidia and microsporidia diagnosis were performed on 260 stool samples. Baseline characteristics regarding relevant demographics, place of residence and living conditions, clinical features including diarrhea, were collected using a standardized questionnaire. PRINCIPAL FINDINGS: The 137 patients were young (median age: 36 years and severely immunocompromised (83.9% at WHO stage 3 or 4, median CD4 cell count: 41/mm3. Diarrhea was present in 43.0% of patients. Parasite infection was found in 78.8% of patients, infection with at least two species in 49.6%. Prevalence rates of protozoan and helminth infections were similar (54.7% and 58.4% respectively. Blastocystis sp. was the most frequent protozoa (26.3%. Cryptosporidium sp., Cytoisospora belli and microsporidia, found at low prevalence rates (6.6%, 4.4%, 2.9%, respectively, were described for the first time in Laos. Cryptosporidium sp. was associated with persistent diarrhea. Strongyloides stercoralis was the most prevalent helminth following Opisthorchis viverrini (20.4% and 47.5% respectively. The most immunocompromised patients, as assessed by a CD4 count ≤ 50 cells/mm3, were more likely to be infected with intestinal parasites. CONCLUSIONS/SIGNIFICANCE: HIV infection was mainly diagnosed at an advanced stage of immunosuppression in Lao patients. Intestinal parasite infections were highly prevalent

Shewanella putrefaciens infective endocarditis

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Jonathan Constant

2014-11-01

Full Text Available Shewanella putrefaciens rarely causes infection in humans. In the last few decades a growing number of cases have been described. The following report outlines the case of a 40-year-old immunocompetent white man with S. putrefaciens infective endocarditis. This is the first known case of infective endocarditis due to an apparently monomicrobial S. putrefaciens infection, and the second known case of S. putrefaciens-related infective endocarditis worldwide.

Impact of environmental factors on neglected emerging arboviral diseases.

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Camila Lorenz

2017-09-01

Full Text Available Brazil is a tropical country that is largely covered by rainforests and other natural ecosystems, which provide ideal conditions for the existence of many arboviruses. However, few analyses have examined the associations between environmental factors and arboviral diseases. Thus, based on the hypothesis of correlation between environment and epidemiology, the proposals of this study were (1 to obtain the probability of occurrence of Oropouche, Mayaro, Saint Louis and Rocio fevers in Brazil based on environmental conditions corresponding to the periods of occurrence of the outbreaks; (2 to describe the macroclimatic scenario in Brazil in the last 50 years, evaluating if there was any detectable tendency to increase temperatures and (3 to model future expansion of those arboviruses in Brazil based on future temperature projections.Our model assessed seven environmental factors (annual rainfall, annual temperature, elevation, seasonality of temperature, seasonality of precipitation, thermal amplitude, and daytime temperature variation for their association with the occurrence of outbreaks in the last 50 years. Our results suggest that various environmental factors distinctly influence the distribution of each arbovirus, with temperature being the central determinant of disease distribution in all high-risk areas. These areas are subject to change, since the average temperature of some areas has increased significantly over the time.This is the first spatio-temporal study of the Oropouche, Mayaro, Saint Louis, and Rocio arboviruses, and our results indicate that they may become increasingly important public health problems in Brazil. Thus, next studies and control programs should include these diseases and also take into consideration key environmental elements.

Rotavirus Infections

Science.gov (United States)

Rotavirus is a virus that causes gastroenteritis. Symptoms include severe diarrhea, vomiting, fever, and dehydration. Almost all ... the U.S. are likely to be infected with rotavirus before their 5th birthday. Infections happen most often ...

Sentinel surveillance of HIV-1 transmitted drug resistance, acute infection and recent infection.

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Hong-Ha M Truong

Full Text Available HIV-1 acute infection, recent infection and transmitted drug resistance screening was integrated into voluntary HIV counseling and testing (VCT services to enhance the existing surveillance program in San Francisco. This study describes newly-diagnosed HIV cases and characterizes correlates associated with infection.A consecutive sample of persons presenting for HIV VCT at the municipal sexually transmitted infections (STI clinic from 2004 to 2006 (N = 9,868 were evaluated by standard enzyme-linked immunoassays (EIA. HIV antibody-positive specimens were characterized as recent infections using a less-sensitive EIA. HIV-RNA pooled testing was performed on HIV antibody-negative specimens to identify acute infections. HIV antibody-positive and acute infection specimens were evaluated for drug resistance by sequence analysis. Multivariable logistic regression was performed to evaluate associations. The 380 newly-diagnosed HIV cases included 29 acute infections, 128 recent infections, and 47 drug-resistant cases, with no significant increases or decreases in prevalence over the three years studied. HIV-1 transmitted drug resistance prevalence was 11.0% in 2004, 13.4% in 2005 and 14.9% in 2006 (p = 0.36. Resistance to non-nucleoside reverse transcriptase inhibitors (NNRTI was the most common pattern detected, present in 28 cases of resistance (59.6%. Among MSM, recent infection was associated with amphetamine use (AOR = 2.67; p<0.001, unprotected anal intercourse (AOR = 2.27; p<0.001, sex with a known HIV-infected partner (AOR = 1.64; p = 0.02, and history of gonorrhea (AOR = 1.62; p = 0.03.New HIV diagnoses, recent infections, acute infections and transmitted drug resistance prevalence remained stable between 2004 and 2006. Resistance to NNRTI comprised more than half of the drug-resistant cases, a worrisome finding given its role as the backbone of first-line antiretroviral therapy in San Francisco as well as worldwide. The integration of HIV-1 drug

Susceptible-infected-recovered and susceptible-exposed-infected models

International Nuclear Information System (INIS)

Tome, Tania; De Oliveira, Mario J

2011-01-01

Two stochastic epidemic lattice models, the susceptible-infected-recovered and the susceptible-exposed-infected models, are studied on a Cayley tree of coordination number k. The spreading of the disease in the former is found to occur when the infection probability b is larger than b c = k/2(k - 1). In the latter, which is equivalent to a dynamic site percolation model, the spreading occurs when the infection probability p is greater than p c = 1/(k - 1). We set up and solve the time evolution equations for both models and determine the final and time-dependent properties, including the epidemic curve. We show that the two models are closely related by revealing that their relevant properties are exactly mapped into each other when p = b/[k - (k - 1)b]. These include the cluster size distribution and the density of individuals of each type, quantities that have been determined in closed forms.

Clinical, Serological, and Molecular Observations from a Case Series Study during the Asian Lineage Zika Virus Outbreak in Grenada during 2016

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Marco Brenciaglia

2018-01-01

Full Text Available This paper describes the spatial and temporal distribution of cases, demographic characteristics of patients, and clinical manifestations of Zika virus (ZIKV during the 2016 outbreak in Grenada. The first reported case was recorded in St. Andrew Parish in April, and the last reported case was seen in November, with peak transmission occurring in the last week of June, based on test results. Data were collected from a total of 514 patients, of whom 207 (40% tested positive for ZIKV. No evidence was found that testing positive for ZIKV infection was related to age, gender, or pregnancy status. Clinical presentation with rash (OR = 2.4, 95% CI = 1.5 to 3.7 or with lymphadenopathy (OR = 1.7, 95% CI = 1.0 to 2.9 were the only reported symptoms consistent with testing positive for ZIKV infection. During the Zika outbreak, the infection rate was 20 clinical cases per 10,000 in the population compared to 41 cases per 10,000 during the chikungunya outbreak in Grenada in 2014 and 17 cases per 10,000 during the dengue outbreak in 2001-2002. Even though the country has employed vector control programs, with no apparent decrease in infection rates, it appears that new abatement approaches are needed to minimize morbidity in future arbovirus outbreaks.

Viral infection of the pregnant cervix predisposes to ascending bacterial infection

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Racicot, Karen; Cardenas, Ingrid; Wünsche, Vera; Aldo, Paulomi; Guller, Seth; Means, Robert; Romero, Roberto; Mor, Gil

2014-01-01

Preterm birth is the major cause of neonatal mortality and morbidity, and bacterial infections that ascend from the lower female reproductive tract (FRT) are the most common route of uterine infection leading to preterm birth. The uterus and growing fetus are protected from ascending infection by the cervix, which controls and limits microbial access by the production of mucus, cytokines and anti-microbial peptides (AMPs). If this barrier is compromised, bacteria may enter the uterine cavity leading to preterm birth. Using a mouse model, we demonstrate, for the first time, that viral infection of the cervix, during pregnancy, reduces the capacity of the FRT to prevent bacterial infection of the uterus. This is due to differences in susceptibility of the cervix to infection by virus during pregnancy and the associated changes in TLR and AMP expression and function. We suggest that preterm labor is a polymicrobial disease, which requires a multifactorial approach for its prevention and treatment. PMID:23752614

HIV-infected mental health patients: characteristics and comparison with HIV-infected patients from the general population and non-infected mental health patients

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Schadé Annemiek

2013-01-01

Full Text Available Abstract Objectives HIV-infected patients are at increased risk of developing mental health symptoms, which negatively influence the treatment of the HIV-infection. Mental health problems in HIV-infected patients may affect public health. Psychopathology, including depression and substance abuse, can increase hazardous sexual behaviour and, with it, the chance of spreading HIV. Therefore, it is important to develop an optimal treatment plan for HIV-infected patients with mental health problems. The majority of HIV-infected patients in the Netherlands (almost 60% are homosexual men. The main objectives of this study were to describe the clinical and demographic characteristics of patients with HIV who seek treatment for their mental health symptoms in the Netherlands. Secondly, we tested whether HIV infected and non-infected homosexual patients with a lifetime depressive disorder differed on several mental health symptoms. Methods We compared a cohort of 196 patients who visited the outpatient clinic for HIV and Mental Health with HIV-infected patients in the general population in Amsterdam (ATHENA-study and with non-HIV infected mental health patients (NESDA-study. DSM-IV diagnoses were determined, and several self-report questionnaires were used to assess mental health symptoms. Results Depressive disorders were the most commonly occurring diagnoses in the cohort and frequent drug use was common. HIV-infected homosexual men with a depressive disorder showed no difference in depressive symptoms or sleep disturbance, compared with non-infected depressive men. However, HIV-positive patients did express more symptoms like fear, anger and guilt. Although they showed significantly more suicidal ideation, suicide attempts were not more prevalent among HIV-infected patients. Finally, the HIV-infected depressive patients displayed a considerably higher level of drug use than the HIV-negative group. Conclusion Habitual drug use is a risk factor for

[ZIKA--VIRUS INFECTION].

Science.gov (United States)

Velev, V

2016-01-01

This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection.

Biofilm Infections

DEFF Research Database (Denmark)

Bjarnsholt, Thomas; Jensen, Peter Østrup; Moser, Claus Ernst

A still increasing interest and emphasis on the sessile bacterial lifestyle biofilms has been seen since it was realized that the vast majority of the total microbial biomass exists as biofilms. Aggregation of bacteria was first described by Leeuwenhoek in 1677, but only recently recognized...... as being important in chronic infection. In 1993 the American Society for Microbiology (ASM) recognized that the biofilm mode of growth was relevant to microbiology. This book covers both the evidence for biofilms in many chronic bacterial infections as well as the problems facing these infections...... such as diagnostics, pathogenesis, treatment regimes and in vitro and in vivo models for studying biofilms. This is the first scientific book on biofilm infections, chapters written by the world leading scientist and clinicians. The intended audience of this book is scientists, teachers at university level as well...

Psychological Distress and Zika, Dengue and Chikungunya Symptoms Following the 2016 Earthquake in Bahía de Caráquez, Ecuador.

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Stewart-Ibarra, Anna M; Hargrave, Anita; Diaz, Avriel; Kenneson, Aileen; Madden, David; Romero, Moory M; Molina, Juan Pablo; Saltos, David Macias

2017-12-05

On 16 April 2016, a 7.8 magnitude earthquake struck coastal Ecuador, resulting in significant mortality and morbidity, damages to infrastructure, and psychological trauma. This event coincided with the first outbreak of Zika virus (ZIKV) and co-circulation with dengue virus (DENV) and chikungunya virus (CHIKV). We tested whether the degree of psychological distress was associated with the presence of suspected DENV, CHIKV, ZIKV (DCZ) infections three months after the earthquake. In July 2016, 601 household members from four communities in Bahía de Caráquez, Manabí Province, Ecuador, were surveyed in a post-disaster health evaluation. Information was collected on demographics, physical damages and injuries, chronic diseases, self-reported psychological distress, and DCZ symptoms. We calculated the prevalence of arbovirus and distress symptoms by community. ANOVA was used to compare the mean number of psychological distress symptoms between people with versus without suspected DCZ infections by age, gender, community and the need to sleep outside of the home due to damages. The prevalence of suspected DCZ infections was 9.7% and the prevalence of psychological distress was 58.1%. The average number of psychological distress symptoms was significantly higher among people with suspected DCZ infections in the periurban community of Bella Vista, in women, in adults 40-64 years of age and in individuals not sleeping at home ( p < 0.05). The results of this study highlight the need to investigate the interactions between psychological distress and arboviral infections following natural disasters.

Infection,

Science.gov (United States)

1980-10-16

characteristic in severe gram-negative sepsis. Hypertriglyceridemia results from an increase in hepatic synthesis in combination with diminished activity of...induced stress, and tissue repair (1). The magnitude and type of nutritional losses caused by an infection reflect both the severity and duration of an... several functional forms of nutrient loss must be anticipated. Functional losses are defined as the within-body losses of nutrients due to infection

Mayaro and Chikungunya; two alphaviruses with clinical and epidemiological similarities

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Salim Mattar V

2015-11-01

Full Text Available In 1780, Philadelphia suffered an unusual outbreak of hemorrhagic fever, which years later was identified as dengue (1. One hundred years later, in Memphis, 1500 people died from yellow fever, which caused residents to abandoned the city (2. Even though these stories may seem anecdotes, they show how dramatic hemorrhagic arbovirus outbreaks can be. The tropic host arboviruses such as Chikungunya (CHIKV, Dengue, and Zika (ZIKV; but there are others, such as Mayaro, Oropuche, and Bussuquara, among others, which have still not been studied in depth by the public health systems of our countries.

Molecular characterization of an Akabane virus isolate from West Java, Indonesia.

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Purnomo Edi, Suryo; Ibrahim, Afif; Sukoco, Rinto; Bunali, Lukman; Taguchi, Masaji; Kato, Tomoko; Yanase, Tohru; Shirafuji, Hiroaki

2017-04-08

We isolated an arbovirus from bovine blood in Indonesia. The arbovirus was obtained from the plasma of a cow showing no clinical symptoms in West Java in February 2014, and was identified as Akabane virus (AKAV) by AKAV-specific RT-PCR and subsequent sequence analysis. Phylogenetic analysis based on partial S segment indicated the AKAV isolate, WJ-1SA/P/2014, was most closely related with two isolates from Israel and Turkey reported in 2001 and 2015, respectively, and that WJ-1SA/P/2014 isolate belongs to AKAV genogroup Ib. This is the first isolation of AKAV from Indonesia.

World Reference Center for Arboviruses.

Science.gov (United States)

1981-02-01

Aride Ken T 100 Barur Hanawa Boraceia Malakal Bov.Eph.Fever N.S.D. Bimbo Nodamura Clo-Mor Pahayokee - *Gomoka Sakhalin Ippy Shark River Kolongo Swan P...of the index case, a resident physician and an auxiliary nurse , both of whom died on September 19th. From that time until September 20, 1980, a total

World Reference Center for Arboviruses

Science.gov (United States)

1994-06-07

Rodriguez, S.C., Tesh, R., Travassos da Rosa, J.F.S., and Travassos da Rosa, E.S. Infeccao humana adquirida in laboratorio causada pelo virus SPH 114202...Arenavirus: familia Arenaviridae): Aspectos clinicos e laboratoriais. Rev. Inst. Med. Trop. Sao Paulo 35:521-525, 1993. Vodkin, M.H., McLaughlin, G.L

World Reference Center for Arboviruses.

Science.gov (United States)

1994-05-29

are rural comprising a patchwork of savanna, gallery forest, and cultivated lands. Most of the population is involved in agriculture and cattle raising...JEV, 3.8 x 5 dex LD50 as determined by titration using l ittermates. Next, pigs were immunized. Groups of 5 Landrace cross- castrated swine of

Hand infections: anatomy, types and spread of infection, imaging findings, and treatment options.

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Patel, Dakshesh B; Emmanuel, Neelmini B; Stevanovic, Milan V; Matcuk, George R; Gottsegen, Christopher J; Forrester, Deborah M; White, Eric A

2014-01-01

Infections of the hand are common, particularly in immunocompromised patients, and can lead to significant morbidity, including amputation, if not treated properly. Hand infection can spread far and wide from the original site of inoculation through interconnections between the synovium-lined and nonsynovial potential spaces. Because surgery is the mainstay of treatment, knowledge of the pertinent anatomy is imperative for accurately describing the presence, location, and extent of infection. The authors review the pertinent anatomy of the spaces of the hand and describe different types of infection-including cellulitis, necrotizing fasciitis, paronychia, felon, pyogenic flexor tenosynovitis, deep space infections, septic arthritis, and osteomyelitis-and common causative organisms of these infections. They also describe various modes of spread; the common radiologic appearances of hand infections, with emphasis on findings at magnetic resonance imaging and ultrasonography; and the role of radiology in the management of these infections, along with a brief overview of treatment options. ©RSNA, 2014.

Postoperative spine infections

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Paolo Domenico Parchi

2015-09-01

Full Text Available Postoperative spinal wound infection is a potentially devastating complication after operative spinal procedures. Despite the utilization of perioperative prophylactic antibiotics in recent years and improvements in surgical technique and postoperative care, wound infection continues to compromise patients’ outcome after spinal surgery. In the modern era of pending health care reform with increasing financial constraints, the financial burden of post-operative spinal infections also deserves consideration. The aim of our work is to give to the reader an updated review of the latest achievements in prevention, risk factors, diagnosis, microbiology and treatment of post-operative spinal wound infections. A review of the scientific literature was carried out using electronic medical databases Pubmed, Google Scholar, Web of Science and Scopus for the years 1973-2012 to obtain access to all publications involving the incidence, risk factors, prevention, diagnosis, treatment of postoperative spinal wound infections. We initially identified 119 studies; of these 60 were selected. Despite all the measures intended to reduce the incidence of surgical site infections in spine surgery, these remain a common and potentially dangerous complication.

Alarming incidence of hepatitis C virus re-infection after treatment of sexually acquired acute hepatitis C virus infection in HIV-infected MSM

NARCIS (Netherlands)

Lambers, Femke A. E.; Prins, Maria; Thomas, Xiomara; Molenkamp, Richard; Kwa, David; Brinkman, Kees; van der Meer, Jan T. M.; Schinkel, Janke; Countinho, R.; Reesink, H.; van Baarle, D.; Smit, C.; Gras, L.; van der Veldt, W.

2011-01-01

Recent data indicate that seroprevalence of sexually transmitted hepatitis C virus (HCV) infection among MSM is stabilizing in Amsterdam. However, little is known about the incidence of HCV re-infection in MSM who have cleared their HCV infection. We, therefore, studied the incidence of re-infection

Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

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Xu, Qingfu; Wischmeyer, Jareth; Gonzalez, Eduardo; Pichichero, Michael E

2017-07-01

We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Factors associated with urinary tract infections among HIV-1 infected patients.

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Agata Skrzat-Klapaczyńska

Full Text Available Urinary tract infections remain an important yet underinvestigated clinical problem among HIV infected patients. Here we analyze factors associated with its occurrence and the spectrum of bacterial pathogens identified in the group of patients followed at the HIV Out-Patient Clinic in Warsaw.Clinic database collected all medical information on patients routinely followed since 1994 to 2015. All patients with available urine culture were included into analyses, only the first culture was included. In statistical analyses logistic regression models were used to identify factors associated with positive culture.In total 608 patients had urine culture performed, 176 (28.9% were females and 432 (71,1% were males, 378 (62.2% registered in care before/in 2007, 258 (42.4% infected through homosexual contact. Median baseline lymphocyte CD4+ count was 385 (IQR:204-565 cells/μl and median nadir lymphocyte CD4+ count 197 (86-306 cells/μl. One hundred and eighteen patients were actively infected with HCV, as defined by positive real-time PCR. In total 141 (23.2% patients had positive urine culture, the most common bacterial pathogen was E.coli (58.2% and E. faecalis (12.8%. Patients with urinary tract infection were more likely to be female (51.8% vs. 22.1%, p<0.0001, infected through other than homosexual mode (80.1% vs. 50.7%, p<0.0001, with lower nadir CD4 count (139 vs. 221 cells/μl, p<0.0001 and lower baseline HIV RNA (4.02 vs. 4.35 log copies/ml, p = 0.01 and less likely to be HCV RNA positive (26.9% vs. 49.2%, p = 0.01. In multivariate regression model being registered before/in 2007 (OR = 2.10; [95%CI: 1.24-3.56], infected through other than homosexual mode (2.05;[1.18-3.56] and female gender (2.14;[1.33-3.44] were increasing and higher nadir CD4+ count decreasing (0.92;[0.85-0.99] the odds of urinary tract infection.We have identified that almost one third of patients had urinary tract infections with non-typical bacterial pathogens. Population

Emmonsia helica Infection in HIV-Infected Man, California, USA.

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Rofael, Martin; Schwartz, Ilan S; Sigler, Lynne; Kong, Li K; Nelson, Nicholas

2018-01-01

Emmonsia-like fungi have rarely been reported from North America. We report a fatal case of E. helica infection in a man with advanced HIV infection from California, USA, who had progressive respiratory failure and a brain abscess.

Lung Infections in Systemic Rheumatic Disease: Focus on Opportunistic Infections.

Science.gov (United States)

Di Franco, Manuela; Lucchino, Bruno; Spaziante, Martina; Iannuccelli, Cristina; Valesini, Guido; Iaiani, Giancarlo

2017-01-29

Systemic rheumatic diseases have significant morbidity and mortality, due in large part to concurrent infections. The lung has been reported among the most frequent sites of infection in patients with rheumatic disease, who are susceptible to developing pneumonia sustained both by common pathogens and by opportunistic microorganisms. Patients with rheumatic disease show a peculiar vulnerability to infectious complications. This is due in part to intrinsic disease-related immune dysregulation and in part to the immunosuppressive treatments. Several therapeutic agents have been associated to a wide spectrum of infections, complicating the management of rheumatic diseases. This review discusses the most frequent pulmonary infections encountered in rheumatic diseases, focusing on opportunistic agents, consequent diagnostic challenges and appropriate therapeutic strategies.

Infection after pacemaker implantation: infection rates and risk factors associated with infection in a population-based cohort study of 46299 consecutive patients

Science.gov (United States)

Johansen, Jens Brock; Jørgensen, Ole Dan; Møller, Mogens; Arnsbo, Per; Mortensen, Peter Thomas; Nielsen, Jens Cosedis

2011-01-01

Aims Infection is a serious complication of pacemaker (PM) systems. Although the rate of infection has been debated, the figures are largely unknown. We therefore studied the incidence of PM infection and its associated risk factors in the Danish population. Methods and results Since 1982, all PM implantation and removal procedures performed in Denmark have been prospectively recorded in the Danish Pacemaker Register. All patients (n = 46299) who underwent implantation between 1982 and 2007 were included. The total length of surveillance was 236 888 PM-years. The incidence of infection was calculated according to the total number of PM-years. The incidence of surgical site infection (≤365 days after PM implantation) was compared with later infection in first implant and replacement procedures. Multiple-record and multiple-event-per-subject proportional hazards analyses were used to identify the independent risk factors of PM infection. Surgical site infection occurred in 192 cases after first implantation (incidence rate 4.82/1000 PM-years), and in 133 cases after replacement (12.12/1000 PM-years). Infections occurring more than 365 days after the first implantation occurred in 153 cases (1.02/1000 PM-years), and in 118 cases after replacement (3.26/1000 PM-years). Independent factors associated with an increased risk of PM infection were a greater number of PM operations (including replacements), male sex, younger age, implantation during the earliest part of the study period, and absence of antibiotics (P< 0.001). Conclusion The overall risk of infection after PM implantation was low. A greater number of operations augmented the risk of infection. This should be taken into account when considering revisions of PM systems. PMID:21252172

Imaging of hepatic infections

International Nuclear Information System (INIS)

Doyle, D.J.; Hanbidge, A.E.; O'Malley, M.E.

2006-01-01

Imaging plays a significant role in the detection, characterization and treatment of hepatic infections. Infectious diseases of the liver include pyogenic and amoebic abscesses and parasitic, fungal, viral and granulomatous infections. With increases in worldwide travel, immunosuppression and changing population demographics, identification of cases of hepatic infection is becoming more common in daily practice. Knowledge of the imaging features seen with hepatic infections can assist in early diagnosis and timely initiation of appropriate therapy. This review presents the imaging appearances of hepatic infections, emphasizing specific features that may contribute to the diagnosis. Examples of the imaging findings seen with pyogenic and amoebic abscesses, infection with Echinococcus granulosus (Hydatid), schistosomiasis, candidiasis and tuberculosis (TB) are presented

Imaging of hepatic infections

Energy Technology Data Exchange (ETDEWEB)

Doyle, D.J. [Department of Medical Imaging, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ont. (Canada)]. E-mail: doyledj@hotmail.com; Hanbidge, A.E. [Department of Medical Imaging, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ont. (Canada); O' Malley, M.E. [Department of Medical Imaging, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ont. (Canada)

2006-09-15

Imaging plays a significant role in the detection, characterization and treatment of hepatic infections. Infectious diseases of the liver include pyogenic and amoebic abscesses and parasitic, fungal, viral and granulomatous infections. With increases in worldwide travel, immunosuppression and changing population demographics, identification of cases of hepatic infection is becoming more common in daily practice. Knowledge of the imaging features seen with hepatic infections can assist in early diagnosis and timely initiation of appropriate therapy. This review presents the imaging appearances of hepatic infections, emphasizing specific features that may contribute to the diagnosis. Examples of the imaging findings seen with pyogenic and amoebic abscesses, infection with Echinococcus granulosus (Hydatid), schistosomiasis, candidiasis and tuberculosis (TB) are presented.

Does a feline leukemia virus infection pave the way for Bartonella henselae infection in cats?

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Buchmann, Alexandra U; Kershaw, Olivia; Kempf, Volkhard A J; Gruber, Achim D

2010-09-01

Domestic cats serve as the reservoir hosts of Bartonella henselae and may develop mild clinical symptoms or none after experimental infection. In humans, B. henselae infection can result in self-limiting cat scratch disease. However, immunocompromised patients may suffer from more-severe courses of infection or may even develop the potentially lethal disease bacillary angiomatosis. It was reasoned that cats with immunocompromising viral infections may react similarly to B. henselae infection. The aim of our study was to investigate the influence of the most important viruses known to cause immunosuppression in cats-Feline leukemia virus (FeLV), Feline immunodeficiency virus (FIV), and Feline panleukopenia virus (FPV)-on natural B. henselae infection in cats. Accordingly, 142 cats from animal shelters were necropsied and tested for B. henselae and concurrent infections with FeLV, FIV, or FPV by PCR and immunohistochemistry. A significant association was found between B. henselae and FeLV infections (P = 0.00028), but not between B. henselae and FIV (P = 1.0) or FPV (P = 0.756) infection, age (P = 0.392), or gender (P = 0.126). The results suggest that susceptibility to B. henselae infection is higher in cats with concurrent FeLV infections, regardless of whether the infection is latent or progressive. Histopathology and immunohistochemistry for B. henselae failed to identify lesions that could be attributed specifically to B. henselae infection. We conclude that the course of natural B. henselae infection in cats does not seem to be influenced by immunosuppressive viral infections in general but that latent FeLV infection may predispose cats to B. henselae infection or persistence.

Gonococcal Prosthetic Joint Infection.

Science.gov (United States)

Gassiep, Ian; Gilpin, Bradley; Douglas, Joel; Siebert, David

2017-01-01

Neisseria gonorrhoea is a common sexually transmitted infection worldwide. Disseminated gonococcal infection is an infrequent presentation and rarely can be associated with septic arthritis. Incidence of this infection is rising, both internationally and in older age groups. We present the first documented case of N. gonorrhoea prosthetic joint infection which was successfully treated with laparoscopic debridement and antimicrobial therapy.

Clinical symptoms and laboratory findings supporting early diagnosis of Crimean-Congo hemorrhagic fever in Iran.

Science.gov (United States)

Mostafavi, Ehsan; Pourhossein, Behzad; Chinikar, Sadegh

2014-07-01

Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic disease, which is usually transmitted to humans by tick bites or contact with blood or other infected tissues of livestock. Patients suffering from CCHF demonstrate an extensive spectrum of clinical symptoms. As it can take considerable time from suspecting the disease in hospital until reaching a definitive diagnosis in the laboratory, understanding the clinical symptoms and laboratory findings of CCHF patients is of paramount importance for clinicians. The data were collected from patients who were referred to the Laboratory of Arboviruses and Viral Hemorrhagic Fevers at the Pasteur institute of Iran with a primary diagnosis of CCHF between 1999 and 2012 and were assessed by molecular and serologic tests. Referred patients were divided into two groups: patients with a CCHF positive result and patients with a CCHF negative result. The laboratory and clinical findings of these two groups were then compared. Two-thousand five hundred thirty-six probable cases of CCHF were referred to the laboratory, of which 871 cases (34.3%) were confirmed to be CCHF. Contact with infected humans and animals increased the CCHF infection risk (P important role in patient survival and the application of the findings of this study can prove helpful as a key for early diagnosis. © 2014 Wiley Periodicals, Inc.

Animal models of yellow fever and their application in clinical research.

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Julander, Justin G

2016-06-01

Yellow fever virus (YFV) is an arbovirus that causes significant human morbidity and mortality. This virus has been studied intensively over the past century, although there are still no treatment options for those who become infected. Periodic and unpredictable yellow fever (YF) outbreaks in Africa and South America continue to occur and underscore the ongoing need to further understand this viral disease and to develop additional countermeasures to prevent or treat cases of illness. The use of animal models of YF is critical to accomplishing this goal. There are several animal models of YF that replicate various aspects of clinical disease and have provided insight into pathogenic mechanisms of the virus. These typically include mice, hamsters and non-human primates (NHP). The utilities and shortcomings of the available animal models of YF are discussed. Information on recent discoveries that have been made in the field of YFV research is also included as well as important future directions in further ameliorating the morbidity and mortality that occur as a result of YFV infection. It is anticipated that these model systems will help facilitate further improvements in the understanding of this virus and in furthering countermeasures to prevent or treat infections. Copyright © 2016 Elsevier B.V. All rights reserved.

Bovine Ephemeral Fever As A Disease Related To Climate Change

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Indrawati Sendow

2013-06-01

Full Text Available Bovine Ephemeral Fever (BEF is one of arbovirus diseases infecting in ruminants especially cattle and buffaloes, which is transmitted by mosquito vectors. In general, vector borne disease is also related to climate change, that mosquito as a vector will significantly increase when the environment temperature increases. The disease was found in many countries in Asia, Africa and Australia. The clinical sign of the disease such as fever to paralysis causes economical impact to the farmer, eventhough the mortality is very low. This review will discuss the disease in relation to climate change, which affects vector population that spread the disease. The more population of vector is the higher chance of animal to be infected. This condition describes that the spread of BEF will depend on some factors included the increase of vectors, the availability of susceptible host and vector media facilities, climate condition and supportive ecology. This paper will discuss the feature of BEF, mode of transmission, the impact of environment and climate change, disease prevention and control, and other aspects to prevent further economical impact. It will also discuss how to the transmission, prevention and control of disease BEF. The information can be taken as an input for policy makers to prevent BEF infection in Indonesia.

Detection of Leishmania amazonensis and Leishmania braziliensis in Culicoides (Diptera, Ceratopogonidae) in an endemic area of cutaneous leishmaniasis in the Brazilian Amazonia.

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Rebêlo, José Manuel Macário; Rodrigues, Bruno Leite; Bandeira, Maria da Conceição Abreu; Moraes, Jorge Luiz Pinto; Fonteles, Raquel Silva; Pereira, Silma Regina Ferreira

2016-12-01

Biting midges in the genus Culicoides act as vectors of arboviruses throughout the world and as vectors of filariasis in Latin America, the Caribbean, and parts of Africa. Although Culicoides spp. are currently not considered to be vectors of Leishmania protozoa, the high abundance of biting midges in areas with active cutaneous leishmaniasis transmission points to the possibility of Culicoides infection by these pathogens. We used PCR to test captured Culicoides species for natural infection with Leishmania spp. We tested 450 Culicoides females, divided into 30 pools of 15 individuals each, as follows: nine pools of C. foxi (135 specimens), seven pools of C. filariferus (105), seven pools of C. insignis (105), five pools of C. ignacioi (75), and two pools of C. flavivenula (30). PCR confirmed the presence of Leishmania braziliensis DNA in C. ignacioi (0.14%), C. insignis (0.14%), and C. foxi (0.11); and Le. amazonensis DNA in C. filariferus (0.14%) and C. flavivenula (0.50%). We conclude that these Culicoides species can be naturally infected, but vector competence and transmission capability must be confirmed in future studies. Our results warrant further investigation into the role of these biting midge species in the leishmaniasis epidemiological cycle. © 2016 The Society for Vector Ecology.

Sports behaviour among HIV-infected versus non-infected individuals in a Berlin cohort.

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Stein, L; Hechler, D; Jessen, A B; Neumann, K; Jessen, H; Beneke, R

2012-01-01

Physical activity has been recommended based on beneficial effects described in HIV-infected patients. However, such guidelines do not take into account actual sport behaviours and general attitudes towards physical activity. To evaluate actual sport activity and attitudes towards sport in HIV-infected versus non-infected individuals we conducted an anonymous questionnaire investigating the prevalence, as well as possible changes, in sports engagement and the overall attitude to physical activity. A total of 283 patients of a general care facility specialized in the treatment of HIV/AIDS in Berlin, Germany, participated; 124 were HIV infected and 159 were non-infected, mostly men who have sex with men (MSM) (88%), with a median age of 35 years. The HIV-infected participants had a median CD4+ count of 554 cells/µL and 48.8% of them were using antiretroviral therapy (ART) at the time of survey. The proportion of patients actually performing physical activity was significantly lower (P = 0.028) within the HIV-infected group (61.3%) than within the non-infected group (74.2%). This difference remained significant after accounting for possible confounders such as age, gender, injecting drug use and sexual preferences. Previously reported sport activity prevalence was similar in both groups on leaving school. From our data we could not identify an association between the time of HIV diagnosis and changes in sports activity. In conclusion, fewer HIV-infected individuals report physical activity than non-infected individuals. Sociodemographic studies to evaluate potential differences in sports behaviour are required in order to inform exercise guidelines for HIV-infected patients.

Transient Oral Human Cytomegalovirus Infections Indicate Inefficient Viral Spread from Very Few Initially Infected Cells.

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Mayer, Bryan T; Krantz, Elizabeth M; Swan, David; Ferrenberg, James; Simmons, Karen; Selke, Stacy; Huang, Meei-Li; Casper, Corey; Corey, Lawrence; Wald, Anna; Schiffer, Joshua T; Gantt, Soren

2017-06-15

Cytomegalovirus (CMV) is acquired by the oral route in children, and primary infection is associated with abundant mucosal replication, as well as the establishment of latency in myeloid cells that results in lifelong infection. The efficiency of primary CMV infection in humans following oral exposure, however, is unknown. We consistently detected self-limited, low-level oral CMV shedding events, which we termed transient CMV infections, in a prospective birth cohort of 30 highly exposed CMV-uninfected infants. We estimated the likelihood of transient oral CMV infections by comparing their observed frequency to that of established primary infections, characterized by persistent high-level shedding, viremia, and seroconversion. We developed mathematical models of viral dynamics upon initial oral CMV infection and validated them using clinical shedding data. Transient infections comprised 76 to 88% of oral CMV shedding events. For this high percentage of transient infections to occur, we identified two mathematical prerequisites: a very small number of initially infected oral cells (1 to 4) and low viral infectivity (<1.5 new cells infected/cell). These observations indicate that oral CMV infection in infants typically begins with a single virus that spreads inefficiently to neighboring cells. Thus, although the incidence of CMV infection is high during infancy, our data provide a mechanistic framework to explain why multiple CMV exposures are typically required before infection is successfully established. These findings imply that a sufficiently primed immune response could prevent CMV from establishing latent infection in humans and support the achievability of a prophylactic CMV vaccine. IMPORTANCE CMV infects the majority of the world's population and is a major cause of birth defects. Developing a vaccine to prevent CMV infection would be extremely valuable but would be facilitated by a better understanding of how natural human CMV infection is acquired. We

Infections are a global issue: Infection addresses global issues

NARCIS (Netherlands)

Grobusch, M. P.; Calleri, G.; Bogner, J. R.

2012-01-01

Infections are of unifying global concern, despite regional differences in disease epidemiology, clinical appearance and the instruments to tackle them. The primary aim of Infection is "to be a forum for the presentation and discussion of clinically relevant information on infectious diseasesaEuro

Konjungtivitis Viral: Diagnosis dan Terapi di Pelayanan Kesehatan Primer

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Ratna Sitompul

2017-04-01

Full Text Available Konjungtiva adalah membran mukosa tipis transparan yang melapisi bagian anterior bola mata dan bagian dalam palpebral. Konjungtiva berfungsi sebagai salah satu komponen sistem perlindungan mata dari peradangan dan infeksi. Peradangan konjungtiva disebut konjungtivitis dan infeksi virus merupakan etiologi peradangan akut tersering pada konjungtiva. Virus yang menyebabkan konjungtivitis adalah adenovirus, herpes simpleks, herpes zoster, pox virus, myxovirus, paramyxovirus, dan arbovirus. Konjungtivitis sering terjadi bersama atau sesudah infeksi saluran napas dan umumnya terdapat riwayat kontak dengan pasien konjungtivitis viral. Gejala konjungtivitis viral berupa mata merah, sekret mata berair dan dapat disertai pembesaran kelenjar limfe. Gejala konjungtivitis viral biasanya ringan, dapat sembuh sendiri dan tidak disertai penurunan tajam penglihatan sehingga dapat ditatalaksana di pelayanan kesehatan primer. Meskipun demikian, terdapat kasus-kasus yang bersifat mengancam penglihatan sehingga perlu segera dirujuk ke rumah sakit atau dokter spesialis mata. Konjungtivitis viral sangat menular sehingga pasien perlu mendapat edukasi untuk mengurangi kontak langsung dan tidak langsung agar tidak menjadi sumber infeksi bagi lingkungannya. Konjungtivitis viral dapat sembuh sendiri, namun pemberian air mata buatan, antihistamin topikal, atau kompres dingin berguna untuk meredakan gejala. Terapi antiviral tidak diperlukan untuk konjungtivitis virus, kecuali untuk konjungtivitis herpetik. Kata kunci: epidemi, konjungtivitis, virus.     Viral Conjunctivitis: Diagnosis and Therapy in Primary Health Care   Abstract Conjunctivae is a transparent thin mucosal membrane covering the outer anterior eye and inner palpebrae. This structure is vital for eye defense from inflammation and infection. Inflammation occurring on the conjunctivae is called conjunctivitis and virus is one of the most common etiologic agent. Such viruses are adenovirus, herpes simplex virus

[Nosocomial virus infections].

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Eggers, H J

1986-12-01

Enveloped viruses, e.g. influenza- or varicella viruses may cause highly contagious airborne infections. Their spread is difficult to control, also in hospitals. In the case of influenza and varicella immune prophylaxis and chemotherapy/chemoprophylaxis are possible. This is of particular significance, since varicella and zoster are of increasing importance for immunocompromized patients. Diarrhea is caused to a large extent by viruses. Rotavirus infections play an important role in infancy, and are frequently acquired in the hospital. In a study on infectious gastroenteritis of infants in a hospital we were able to show that 30 percent of all rotavirus infections were of nosocomial origin. Admission of a rotavirus-excreting patient (or personnel) may start a long chain of rotavirus infections on pediatric wards. Even careful hygienic measures in the hospital can hardly prevent the spread of enterovirus infections. Such infections may be severe and lethal for newborns, as shown by us in a study on an outbreak of echovirus 11 disease on a maternity ward. We have recently obtained data on the "stickiness" of enteroviruses on human skin. This could explain essential features of the spread of enteroviruses in the population.

Psychiatric disorders, HIV infection and HIV/hepatitis co-infection in the correctional setting.

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Baillargeon, J G; Paar, D P; Wu, H; Giordano, T P; Murray, O; Raimer, B G; Avery, E N; Diamond, P M; Pulvino, J S

2008-01-01

Psychiatric disorders such as bipolar disorder, schizophrenia and depression have long been associated with risk behaviors for HIV, hepatitis C virus (HCV) and hepatitis B virus (HBV). The US prison population is reported to have elevated rates of HIV, hepatitis and most psychiatric disorders. This study examined the association of six major psychiatric disorders with HIV mono-infection, HIV/HCV co-infection and HIV/HBV co-infection in one of the nation's largest prison populations. The study population consisted of 370,511 Texas Department of Criminal Justice inmates who were incarcerated for any duration between January 1, 2003 and July 1, 2006. Information on medical conditions and sociodemographic factors was obtained from an institution-wide electronic medical information system. Offenders diagnosed with HIV mono-infection, HIV/HCV, HIV/HBV and all HIV combined exhibited elevated rates of major depression, bipolar disorder, schizophrenia, schizoaffective disorder, non-schizophrenic psychotic disorder and any psychiatric disorder. In comparison to offenders with HIV mono-infection, those with HIV/HCV co-infection had an elevated prevalence of any psychiatric disorder. This cross-sectional study's finding of positive associations between psychiatric disease and both HIV infection and hepatitis co-infection among Texas prison inmates holds both clinical and public health relevance. It will be important for future investigations to examine the extent to which psychiatric disorders serve as a barrier to medical care, communication with clinicians and adherence to prescribed medical regimens among both HIV-mono-infected and HIV/hepatitis-co-infected inmates.

Hand infections: a retrospective analysis

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Tolga Türker

2014-09-01

Full Text Available Purpose. Hand infections are common, usually resulting from an untreated injury. In this retrospective study, we report on hand infection cases needing surgical drainage in order to assess patient demographics, causation of infection, clinical course, and clinical management.Methods. Medical records of patients presenting with hand infections, excluding post-surgical infections, treated with incision and debridement over a one-year period were reviewed. Patient demographics; past medical history; infection site(s and causation; intervals between onset of infection, hospital admission, surgical intervention and days of hospitalization; gram stains and cultures; choice of antibiotics; complications; and outcomes were reviewed.Results. Most infections were caused by laceration and the most common site of infection was the palm or dorsum of the hand. Mean length of hospitalization was 6 days. Methicillin-resistant Staphylococcus aureus, beta-hemolytic Streptococcus and methicillin-susceptible Staphylococcus aureus were the most commonly cultured microorganisms. Cephalosporins, clindamycin, amoxicillin/clavulanate, penicillin, vancomycin, and trimethoprim/sulfamethoxazole were major antibiotic choices. Amputations and contracture were the primary complications.Conclusions. Surgery along with medical management were key to treatment and most soft tissue infections resolved without further complications. With prompt and appropriate care, most hand infection patients can achieve full resolution of their infection.

Ability of procalcitonin to discriminate infection from non-infective inflammation using two pleural disease settings.

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Fiona J McCann

Full Text Available Procalcitonin has been shown to be useful in separating infection from non-infective disorders. However, infection is often paralleled by tissue inflammation. Most studies supporting the use of procalcitonin were confounded by more significant inflammation in the infection group. Few studies have examined the usefulness of procalcitonin when adjusted for inflammation.Pleural inflammation underlies the development of most exudative effusions including pleural infection and malignancy. Pleurodesis, often used to treat effusions, involves provocation of intense aseptic pleural inflammation. We conducted a two-part proof-of-concept study to test the specificity of procalcitonin in differentiating infection using cohorts of patients with pleural effusions of infective and non-infective etiologies, as well as subjects undergoing pleurodesis.We measured the blood procalcitonin level (i in 248 patients with pleural infection or with non-infective pleural inflammation, matched for severity of systemic inflammation by C-reactive protein (CRP, age and gender; and (ii in patients before and 24-48 hours after induction of non-infective pleural inflammation (from talc pleurodesis.1 Procalcitonin was significantly higher in patients with pleural infection compared with controls with non-infective effusions (n = 32 each group that were case-matched for systemic inflammation as measured by CRP [median (25-75%IQR: 0.58 (0.35-1.50 vs 0.34 (0.31-0.42 µg/L respectively, p = 0.003]. 2 Talc pleurodesis provoked intense systemic inflammation, and raised serum CRP by 360% over baseline. However procalcitonin remained relatively unaffected (21% rise. 3 Procalcitonin and CRP levels did not correlate. In 214 patients with pleural infection, procalcitonin levels did not predict the survival or need for surgical intervention.Using a pleural model, this proof-of-principle study confirmed that procalcitonin is a biomarker specific for infection and is not affected by non-infective

Freshwater Fungal Infections

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Dennis J. Baumgardner

2017-01-01

Full Text Available Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or fails to resolve with appropriate antibacterial therapy.

High prevalence of human parvovirus 4 infection in HBV and HCV infected individuals in shanghai.

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Yu, Xuelian; Zhang, Jing; Hong, Liang; Wang, Jiayu; Yuan, Zhengan; Zhang, Xi; Ghildyal, Reena

2012-01-01

Human parvovirus 4 (PARV4) has been detected in blood and diverse tissues samples from HIV/AIDS patients who are injecting drug users. Although B19 virus, the best characterized human parvovirus, has been shown to co-infect patients with hepatitis B or hepatitis C virus (HBV, HCV) infection, the association of PARV4 with HBV or HCV infections is still unknown.The aim of this study was to characterise the association of viruses belonging to PARV4 genotype 1 and 2 with chronic HBV and HCV infection in Shanghai.Serum samples of healthy controls, HCV infected subjects and HBV infected subjects were retrieved from Shanghai Center for Disease Control and Prevention (SCDC) Sample Bank. Parvovirus-specific nested-PCR was performed and results confirmed by sequencing. Sequences were compared with reference sequences obtained from Genbank to derive phylogeny trees.The frequency of parvovirus molecular detection was 16-22%, 33% and 41% in healthy controls, HCV infected and HBV infected subjects respectively, with PARV4 being the only parvovirus detected. HCV infected and HBV infected subjects had a significantly higher PARV4 prevalence than the healthy population. No statistical difference was found in PARV4 prevalence between HBV or HCV infected subjects. PARV4 sequence divergence within study groups was similar in healthy subjects, HBV or HCV infected subjects.Our data clearly demonstrate that PARV4 infection is strongly associated with HCV and HBV infection in Shanghai but may not cause increased disease severity.

Urinary tract infection - children

Science.gov (United States)

UTI - children; Cystitis - children; Bladder infection - children; Kidney infection - children; Pyelonephritis - children ... Craig JC. Long-term antibiotics for preventing recurrent urinary tract infection in children. Cochrane Database Syst Rev . 2011;(3):CD001534. PMID: ...

Methicillin-Resistant Staphylococcus aureus Infections in Human Immunodeficiency Virus-Infected Children and Adolescents

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George K. Siberry

2012-01-01

Full Text Available Background. Methicillin-resistant Staphylococcus aureus (MRSA infection incidence has increased in healthy US children. Our objective was to evaluate MRSA incidence and correlates in HIV-infected youth. Methods. The CDC-sponsored LEGACY study is a US multicenter chart abstraction study of HIV-infected youth. We identified MRSA infections among participants with ≥1 visit during 2006. We used bivariate and multivariable analyses to compare sociodemographic and HIV clinical factors between MRSA cases and noncases. Results. Fourteen MRSA infections (1 invasive, 12 soft tissue, 1 indeterminate occurred among 1,813 subjects (11.1 infections/1,000 patient-years (PY, 95% CI: 11.06–11.14. Most (86% isolates were clindamycin susceptible. Compared with noncases, MRSA cases were more likely older (17 versus 14 years, black (100% versus 69%, behaviorally HIV infected (43% versus 17%, and in Maryland (43% versus 7% and had viral loads (VL >1000 copies/mL (86% versus 51% and lower mean CD4% (18% versus 27% (all P1000 copies/mL (aOR = 5.9, and black race (aOR undefined. Conclusions. MRSA occurred at a rate of 11.1 infections/1,000 PY in HIV-infected youth but invasive disease was uncommon. Geographic location, black race, and increased VL, but not immunosuppression, were independently associated with MRSA risk.

A review of the clinical implications of anti-infective biomaterials and infection-resistant surfaces.

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Campoccia, Davide; Montanaro, Lucio; Arciola, Carla Renata

2013-11-01

Infection is currently regarded as the most severe and devastating complication associated to the use of biomaterials. The important social, clinical and economic impacts of implant-related infections are promoting the efforts to obviate these severe diseases. In this context, the development of anti-infective biomaterials and of infection-resistant surfaces is being regarded as the main strategy to prevent the establishment of implant colonisation and biofilm formation by bacteria. In this review, the attention is focused on the biomaterial-associated infections, from which the need for anti-infective biomaterials originates. Biomaterial-associated infections differ markedly for epidemiology, aetiology and severity, depending mainly on the anatomic site, on the time of biomaterial application, and on the depth of the tissues harbouring the prosthesis. Here, the diversity and complexity of the different scenarios where medical devices are currently utilised are explored, providing an overview of the emblematic applicative fields and of the requirements for anti-infective biomaterials. © 2013 Elsevier Ltd. All rights reserved.

Serodiagnosis of dengue infection using rapid immunochromatography test in patients with probable dengue infection.

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Kidwai, Aneela Altaf; Jamal, Qaiser; Saher; Mehrunnisa; Farooqi, Faiz-ur-rehman; Saleem-Ullah

2010-11-01

To determine the frequency of seropositive dengue infection using rapid immunochromatographic assay in patients with probable dengue infection as per WHO criteria. A cross-sectional observational study was conducted at Abbasi Shaheed Hospital, Karachi from July 2008 to January 2009. Patients presenting with acute febrile illness, rashes, bleeding tendencies, leucopenia and or thrombocytopenia were evaluated according to WHO criteria for probable dengue infection. Acute phase sera were collected after 5 days of the onset of fever as per WHO criteria. Serology was performed using rapid immunochromatographic (ICT) assay with differential detection of IgM and IgG. A primary dengue infection was defined by a positive IgM band and a negative IgG band whereas secondary infection was defined by a positive IgG band with or without positive IgM band. Among 599 patients who met the WHO criteria for dengue infection, 251(41.9%) were found to be ICT reactive among whom 42 (16.73%) had primary infection. Secondary infection was reported in 209 (83.26%). Acute phase sera of 348 (58.09%) were ICT non reactive. Four patients died because of dengue shock syndrome among which three had secondary infection. Early identification of secondary infection in acute phase sera using rapid ICT is valuable in terms of disease progression and mortality. However in highly suspected cases of dengue infection clinical management should not rely on negative serological results.

[Non-tuberculous pleural infections versus tuberculous pleural infections].

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Horo, K; N'Gom, A; Ahui, B; Brou-Gode, C; Anon, J-C; Diaw, A; Bemba, P; Foutoupouo, K; Djè Bi, H; Ouattara, P; Kouassi, B; Koffi, N; Aka-Danguy, E

2012-03-01

In countries where tuberculosis is endemic, the main differential diagnosis for pleural infection by common bacteria is pleural tuberculosis. The purpose of our study was to determine the differences between pleural infection by common bacteria and that caused by pleural tuberculosis. Our study was a retrospective analysis and compared the characteristics of confirmed pleural infection by common bacteria (PIB) and that due to pleural tuberculosis (PT). For the PIB, the signs evolved for 2.4 ± 1.4 weeks versus 5.6 ± 2.2 weeks for the PT (P=0.01). In multivariate analysis, for PIB the onset of symptoms was more abrupt (OR=3.8 [1.5; 9.9]; P=0.01), asthenia was less frequent (OR=0.3 [0.1; 0.9]; P=0.03), pleural liquid was more purulent (OR=40.0 [15.0; 106.7]; Ppleural effusions caused by tuberculosis (TB) and those due to other bacterial infections. However, they are not sufficiently sensitive and therefore the search for the tuberculous bacillus must be systematic while waiting for implementation of new diagnostic tests for the organism. Copyright © 2012 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Enterobiasis (Pinworm Infection): Treatment

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... The CDC Cancel Submit Search The CDC Parasites - Enterobiasis (also known as Pinworm Infection) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Pinworm Infection General Information Pinworm Infection FAQs Epidemiology & Risk ...

Enterobiasis (Pinworm Infection): Diagnosis

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... The CDC Cancel Submit Search The CDC Parasites - Enterobiasis (also known as Pinworm Infection) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Pinworm Infection General Information Pinworm Infection FAQs Epidemiology & Risk ...

Occult HBV infection in HIV-infected adults and evaluation of pooled NAT for HBV.

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Dinesha, T R; Boobalan, J; Sivamalar, S; Subashini, D; Solomon, S S; Murugavel, K G; Balakrishnan, P; Smith, D M; Saravanan, S

2018-01-06

The study aimed to determine the prevalence of occult hepatitis B virus infection among HIV-infected persons and to evaluate the use of a pooling strategy to detect occult HBV infection in the setting of HIV infection. Five hundred and two HIV-positive individuals were tested for HBV, occult HBV and hepatitis C and D with serologic and nucleic acid testing (NAT). We also evaluated a pooled NAT strategy for screening occult HBV infection among the HIV-positive individuals. The prevalence of HBV infection among HIV-positive individuals was 32 (6.4%), and occult HBV prevalence was 10%. The pooling HBV NAT had a sensitivity of 66.7% and specificity of 100%, compared to HBV DNA NAT of individual samples. In conclusion, this study found a high prevalence of occult HBV infection among our HIV-infected population. We also demonstrated that pooled HBV NAT is highly specific, moderately sensitive and cost-effective. As conventional HBV viral load assays are expensive in resource-limited settings such as India, pooled HBV DNA NAT might be a good way for detecting occult HBV infection and will reduce HBV-associated complications. © 2018 John Wiley & Sons Ltd.

[The risk of infection to the mother prior, during and after delivery. A registration of nosocomial infections].

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Hirsch, H A; Niehues, U

1982-09-01

During 5 1/2 years all infections arising in the hospital (nosocomial infections) were registered prospectively by an infection control nurse. The incidence of all nosocomial infections in 3192 maternity patients was 2.1%. In 10,569 women following vaginal deliveries 2.6% and in 1,353 women following Caesarean section 21.1%. The commonest infections were urinary tract infections, endometritis, infections of the abdominal wound or the episiotomy, and a phlebitis of the intravenous infusion site. Measures to prevent infection resulted in a steadily decreasing incidence of infections during the 6 years of registration of nosocomial infections.

High infection control rate and function after routine one-stage exchange for chronically infected TKA.

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Jenny, Jean-Yves; Barbe, Bruno; Gaudias, Jeannot; Boeri, Cyril; Argenson, Jean-Noël

2013-01-01

Many surgeons consider two-stage exchange the gold standard for treating chronic infection after TKA. One-stage exchange is an alternative for infection control and might provide better knee function, but the rates of infection control and levels of function are unclear. We asked whether a one-stage exchange protocol would lead to infection control rates and knee function similar to those after two-stage exchange. We followed all 47 patients with chronically infected TKAs treated with one-stage exchange between July 2004 and February 2007. We monitored for recurrence of infection and obtained Knee Society Scores. We followed patients a minimum of 3 years or until death or infection recurrence. Three of the 47 patients (6%) experienced a persistence or recurrence of the index infection with the same pathogen isolated. Three patients (6%) had control of the index infection but between 6 and 17 months experienced an infection with another pathogen. The 3-year survival rates were 87% for being free of any infection and 91% for being healed of the index infection. Twenty-five of the 45 patients (56%) had a Knee Society Score of more than 150 points. While routine one-stage exchange was not associated with a higher rate of infection recurrence failure, knee function was not improved compared to that of historical patients having two-stage exchange. One stage-exchange may be a reasonable alternative in chronically infected TKA as a more convenient approach for patients without the risks of two operations and hospitalizations and for reducing costs. The ideal one stage-exchange candidate should be identified in future studies.

Enterococcus faecalis infective endocarditis

DEFF Research Database (Denmark)

Dahl, Anders; Bruun, Niels Eske

2013-01-01

Enterococcus faecalis infective endocarditis (IE) is a disease of increasing importance, with more patients infected, increasing frequency of health-care associated infections and increasing incidence of antimicrobial resistances. The typical clinical presentation is a subacute course with fever...... or ceftriaxone. E. faecalis infective endocarditis continues to be a very serious disease with considerable percentages of high-level gentamicin resistant strains and in-hospital mortality around 20%. Strategies to prevent E. faecalis IE, improve diagnostics, optimize treatment and reduce morbidity...

Urinary Tract Infections (For Teens)

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... Staying Safe Videos for Educators Search English Español Urinary Tract Infections KidsHealth / For Teens / Urinary Tract Infections What's ... especially girls — visit a doctor. What Is a Urinary Tract Infection? A bacterial urinary tract infection (UTI) is ...

Small Intestinal Infections.

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Munot, Khushboo; Kotler, Donald P

2016-06-01

Small intestinal infections are extremely common worldwide. They may be bacterial, viral, or parasitic in etiology. Most are foodborne or waterborne, with specific etiologies differing by region and with diverse pathophysiologies. Very young, very old, and immune-deficient individuals are the most vulnerable to morbidity or mortality from small intestinal infections. There have been significant advances in diagnostic sophistication with the development and early application of molecular diagnostic assays, though these tests have not become mainstream. The lack of rapid diagnoses combined with the self-limited nature of small intestinal infections has hampered the development of specific and effective treatments other than oral rehydration. Antibiotics are not indicated in the absence of an etiologic diagnosis, and not at all in the case of some infections.

High infection rate of zoonotic Eucoleus aerophilus infection in foxes from Serbia

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Lalošević Vesna

2013-01-01

Full Text Available The respiratory capillariid nematode Eucoleus aerophilus (Creplin, 1839 infects wild and domestic carnivores and, occasionally, humans. Thus far, a dozen of human infections have been published in the literature but it cannot be ruled out that lung capillariosis is underdiagnosed in human medicine. Also, the apparent spreading of E. aerophilus in different geographic areas spurs new studies on the epidemiology of this nematode. After the recognition of the first human case of E. aerophilus infection in Serbia, there is a significant merit in enhancing knowledge on the distribution of the nematode. In the present work the infection rate of pulmonary capillariosis was investigated in 70 red foxes (Vulpes vulpes from the northern part of Serbia by autopsy. The estimated infection rate with Eucoleus aerophilus was 84%. In contrast, by copromicroscopic examination only 38% of foxes were positive. In addition, 10 foxes were investigated for the closely related species in nasal cavity, Eucoleus boehmi, and nine were positive. Our study demonstrates one of the highest infection rates of pulmonary capillariosis in foxes over the world.

Genital mycoplasma & Chlamydia trachomatis infections in treatment naïve HIV-1 infected adults

Science.gov (United States)

Ghosh, Arnab; Dhawan, Benu; Chaudhry, Rama; Vajpayee, Madhu; Sreenivas, Vishnubhatla

2011-01-01

Background & objectives: Sexually transmitted infections (STIs) enhance the transmission of human immunodeficiency virus (HIV). Thus, screening for STIs is a routine component of primary HIV care. There are limited data for selective screening guidelines for genital mycoplasmas and Chlamydia trachomatis in HIV-infected adults. The aim of the present study was to determine the frequency of genital infections with Ureaplasma spp., Mycoplasma hominis, M. genitalium and C. trachomatis in treatment naïve asymptomatic HIV-1 - infected adults and study their association with CD4+ T-cell count. Methods: First-void urine samples were collected from 100 treatment-naïve HIV-1-infected adults and 50 healthy volunteers. C. trachomatis and M. genitalium were detected by polymerase chain reaction (PCR). Ureaplasma spp. and M. hominis were detected by both culture and PCR. Circulating CD4+ cell counts of HIV-1-infected patients were determined from peripheral blood by flow-cytometry. Results: C. trachomatis was detected in 7 per cent of HIV-1-infected adults compared to none in control population. Ureaplasma spp. and M. hominis showed infection rates of 6 and 1 per cent in the HIV group and 2 and 0 per cent in the control group, respectively. None of the individuals from the patient and control groups was tested positive for M. genitalium. A significant association was found between CD4 cell count and detection of C. trachomatis in HIV-infected adults (P = 0.01). Interpretation & conclusions: Screening of HIV-infected individuals for C. trachomatis infection could be recommended as a routine component of HIV care. The role of mycoplasmas as co-pathogens of the genitourinary tract in HIV-1 infected patients seems to be unlikely. Further longitudinal studies need to be done to confirm these findings. PMID:22310829

Prior Puma Lentivirus Infection Modifies Early Immune Responses and Attenuates Feline Immunodeficiency Virus Infection in Cats

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Wendy S. Sprague

2018-04-01

Full Text Available We previously showed that cats that were infected with non-pathogenic Puma lentivirus (PLV and then infected with pathogenic feline immunodeficiency virus (FIV (co-infection with the host adapted/pathogenic virus had delayed FIV proviral and RNA viral loads in blood, with viral set-points that were lower than cats infected solely with FIV. This difference was associated with global CD4+ T cell preservation, greater interferon gamma (IFN-γ mRNA expression, and no cytotoxic T lymphocyte responses in co-infected cats relative to cats with a single FIV infection. In this study, we reinforced previous observations that prior exposure to an apathogenic lentivirus infection can diminish the effects of acute infection with a second, more virulent, viral exposure. In addition, we investigated whether the viral load differences that were observed between PLV/FIV and FIV infected cats were associated with different immunocyte phenotypes and cytokines. We found that the immune landscape at the time of FIV infection influences the infection outcome. The novel findings in this study advance our knowledge about early immune correlates and documents an immune state that is associated with PLV/FIV co-infection that has positive outcomes for lentiviral diseases.

Current management of fungal infections.

NARCIS (Netherlands)

Meis, J.F.G.M.; Verweij, P.E.

2001-01-01

The management of superficial fungal infections differs significantly from the management of systemic fungal infections. Most superficial infections are treated with topical antifungal agents, the choice of agent being determined by the site and extent of the infection and by the causative organism,

Infection after pacemaker implantation: infection rates and risk factors associated with infection in a population-based cohort study of 46299 consecutive patients

DEFF Research Database (Denmark)

Johansen, Jens Brock; Jørgensen, Ole Dan; Møller, Mogens

2011-01-01

Infection is a serious complication of pacemaker (PM) systems. Although the rate of infection has been debated, the figures are largely unknown. We therefore studied the incidence of PM infection and its associated risk factors in the Danish population....

Decision tree for accurate infection timing in individuals newly diagnosed with HIV-1 infection.

Science.gov (United States)

Verhofstede, Chris; Fransen, Katrien; Van Den Heuvel, Annelies; Van Laethem, Kristel; Ruelle, Jean; Vancutsem, Ellen; Stoffels, Karolien; Van den Wijngaert, Sigi; Delforge, Marie-Luce; Vaira, Dolores; Hebberecht, Laura; Schauvliege, Marlies; Mortier, Virginie; Dauwe, Kenny; Callens, Steven

2017-11-29

There is today no gold standard method to accurately define the time passed since infection at HIV diagnosis. Infection timing and incidence measurement is however essential to better monitor the dynamics of local epidemics and the effect of prevention initiatives. Three methods for infection timing were evaluated using 237 serial samples from documented seroconversions and 566 cross sectional samples from newly diagnosed patients: identification of antibodies against the HIV p31 protein in INNO-LIA, SediaTM BED CEIA and SediaTM LAg-Avidity EIA. A multi-assay decision tree for infection timing was developed. Clear differences in recency window between BED CEIA, LAg-Avidity EIA and p31 antibody presence were observed with a switch from recent to long term infection a median of 169.5, 108.0 and 64.5 days after collection of the pre-seroconversion sample respectively. BED showed high reliability for identification of long term infections while LAg-Avidity is highly accurate for identification of recent infections. Using BED as initial assay to identify the long term infections and LAg-Avidity as a confirmatory assay for those classified as recent infection by BED, explores the strengths of both while reduces the workload. The short recency window of p31 antibodies allows to discriminate very early from early infections based on this marker. BED recent infection results not confirmed by LAg-Avidity are considered to reflect a period more distant from the infection time. False recency predictions in this group can be minimized by elimination of patients with a CD4 count of less than 100 cells/mm3 or without no p31 antibodies. For 566 cross sectional sample the outcome of the decision tree confirmed the infection timing based on the results of all 3 markers but reduced the overall cost from 13.2 USD to 5.2 USD per sample. A step-wise multi assay decision tree allows accurate timing of the HIV infection at diagnosis at affordable effort and cost and can be an important

Dengue viral infections

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Gurugama Padmalal

2010-01-01

Full Text Available Dengue viral infections are one of the most important mosquito-borne diseases in the world. Presently dengue is endemic in 112 countries in the world. It has been estimated that almost 100 million cases of dengue fever and half a million cases of dengue hemorrhagic fever (DHF occur worldwide. An increasing proportion of DHF is in children less than 15 years of age, especially in South East and South Asia. The unique structure of the dengue virus and the pathophysiologic responses of the host, different serotypes, and favorable conditions for vector breeding have led to the virulence and spread of the infections. The manifestations of dengue infections are protean from being asymptomatic to undifferentiated fever, severe dengue infections, and unusual complications. Early recognition and prompt initiation of appropriate supportive treatment are often delayed resulting in unnecessarily high morbidity and mortality. Attempts are underway for the development of a vaccine for preventing the burden of this neglected disease. This review outlines the epidemiology, clinical features, pathophysiologic mechanisms, management, and control of dengue infections.

Pediatric spinal infections

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Raj Kumar

2014-01-01

Full Text Available The infections of the spinal axis in children are rare when compared with adults. They encompass a large spectrum of diseases ranging from relatively benign diskitis to spinal osteomyleitis and to the rapidly progressive, rare, and potentially devastating spinal epidural, subdural, and intramedullary spinal cord infections. We present a comprehensive review of the literature pertaining to these uncommon entities, in light of our experience from northern India. The most prevalent pediatric spinal infection in Indian scenario is tuberculosis, where an extradural involvement is more common than intradural. The craniovertebral junction is not an uncommon site of involvement in children of our milieu. The majority of pyogenic infections of pediatric spine are associated with congenital neuro-ectodermal defects such as congenital dermal sinus. The clinico-radiological findings of various spinal infections commonly overlap. Hence the endemicity of certain pathogens should be given due consideration, while considering the differential diagnosis. However, early suspicion, rapid diagnosis, and prompt treatment are the key factors in avoiding neurological morbidity and deformity in a growing child.

HIV-infected mental health patients: characteristics and comparison with HIV-infected patients from the general population and non-infected mental health patients

NARCIS (Netherlands)

Schade, A.; Grootheest, G.; Smit, J.H.

2013-01-01

Objectives: HIV-infected patients are at increased risk of developing mental health symptoms, which negatively influence the treatment of the HIV-infection. Mental health problems in HIV-infected patients may affect public health. Psychopathology, including depression and substance abuse, can

Vaginal yeast infection

Science.gov (United States)

Yeast infection - vagina; Vaginal candidiasis; Monilial vaginitis ... Most women have a vaginal yeast infection at some time. Candida albicans is a common type of fungus. It is often found in small amounts ...

Imaging infection and inflammation

International Nuclear Information System (INIS)

Buscombe, John

1997-01-01

Full text. The use of nuclear medicine techniques to image infection has been with us for over 20 years, indeed this year sees the 20th anniversary of the publication of Matthew Thakur's paper of the use of In-111 oxime labelled leukocytes in imaging infection. Without doubt this technique has stood the test of time and has been used to save many lives in infected patients worldwide. As we approach the 21st century we are faced with new problems which will need new solutions. Infections themselves have changed their very nature, HIV a benign virus which only infected monkeys in central Africa in 1977 has now spread throughout the globe and unfortunately few societies have remained free of its ravages. In its wake tuberculosis continues to infect both the poor and weak but also has started to re-infect more affluent societies. In its wake tuberculosis continues to infect both both the poor and weak but also has started to re-infect more affluent societies. The use of immuno suppressive therapy in many patients with transplants or cancer has lead to new infections in a wider group of patients. The wide spread use of antibiotics has lead to the emergence of antibiotic resistant organisms. The old approach of widespread antibiotic treatment in patients with suspected infection is not acceptable. If possible organisms must be isolated. Normally imaging is required to localize infection and it is important to realize that a combination or anatomical imaging with CT, ultrasound or MRI and nuclear medicine is often the only way to determine the site of infection. Allied to this a new educated public has demanded that diagnostic tests be accurate and non-invasive, particularly in non-fatal inflammatory disease. All these challenges has lead us to a new frontier in nuclear medicine. In some ways we have had to rediscover the old. For example the use of Ga-67 citrate in imaging tuberculosis or infection in patients with Aids. The use of Tc-99 m HMPAO labelled leukocytes in

Congenital and perinatal cytomegalovirus infection

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Chun Soo Kim

2010-01-01

Full Text Available Cytomegalovirus (CMV is currently the most common agent of congenital infection and the leading infectious cause of brain damage and hearing loss in children. Symptomatic congenital CMV infections usually result from maternal primary infection during early pregnancy. One half of symptomatic infants have cytomegalic inclusion disease (CID, which is characterized by involvement of multiple organs, in particular, the reticuloendothelial and central nervous system (CNS. Moreover, such involvement may or may not include ocular and auditory damage. Approximately 90% of infants with congenital infection are asymptomatic at birth. Preterm infants with perinatal CMV infection can have symptomatic diseases such as pneumonia, hepatitis, and thrombocytopenia. Microcephaly and abnormal neuroradiologic imaging are associated with a poor prognosis. Hearing loss may occur in both symptomatic and asymptomatic infants with congenital infection and may progress through childhood. Congenital infection is defined by the isolation of CMV from infants within the first 3 weeks of life. Ganciclovir therapy can be considered for infants with symptomatic congenital CMV infection involving the CNS. Pregnant women of seronegative state should be counseled on the importance of good hand washing and other control measures to prevent CMV infection. Heat treatment of infected breast milk at 72?#608;for 5 seconds can eliminate CMV completely.

[Saccharomyces cerevisiae infections].

Science.gov (United States)

Souza Goebel, Cristine; de Mattos Oliveira, Flávio; Severo, Luiz Carlos

2013-01-01

Saccharomyces cerevisiae is an ubiquitous yeast widely used in industry and it is also a common colonizer of the human mucosae. However, the incidence of invasive infection by these fungi has significantly increased in the last decades. To evaluate the infection by S. cerevisiae in a hospital in southern Brazil during a period of 10 years (2000-2010). Review of medical records of patients infected by this fungus. In this period, 6 patients were found to be infected by S. cerevisiae. The age range of the patients was from 10 years to 84. Urine, blood, ascitic fluid, peritoneal dialysis fluid, and esophageal biopsy samples were analyzed. The predisposing factors were cancer, transplant, surgical procedures, renal failure, use of venous catheters, mechanical ventilation, hospitalization in Intensive Care Unit, diabetes mellitus, chemotherapy, corticosteroid use, and parenteral nutrition. Amphotericin B and fluconazole were the treatments of choice. Three of the patients died and the other 3 were discharged from hospital. We must take special precautions in emerging infections, especially when there are predisposing conditions such as immunosuppression or patients with serious illnesses. The rapid and specific diagnosis of S. cerevisiae infections is important for therapeutic decision. Furthermore, epidemiological and efficacy studies of antifungal agents are necessary for a better therapeutic approach. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

Lactobacillus paracasei feeding improves the control of secondary experimental meningococcal infection in flu-infected mice.

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Belkacem, Nouria; Bourdet-Sicard, Raphaëlle; Taha, Muhamed-Kkeir

2018-04-10

The use of probiotics to improve anti-microbial defence, such as for influenza infections, is increasingly recommended. However, no data are available on the effect of probiotics on flu-associated secondary bacterial infections. There is strong evidence of a spatiotemporal association between influenza virus infection and invasive Neisseria meningitidis. We thus investigated the effect of feeding mice Lactobacillus paracasei CNCM I-1518 in a mouse model of sequential influenza-meningococcal infection. We intranasally infected BALB/c mice with a strain of influenza A virus (IAV) H3N2 that was first adapted to mice. Seven days later, a secondary bacterial infection was induced by intranasal administration of bioluminescent N. meningitidis. During the experiment, mice orally received either L. paracasei CNCM I-1518 or PBS as a control. The effect of L. paracasei administration on secondary bacterial infection by N. meningitidis was evaluated. Oral consumption of L. paracasei CNCM I-1518 reduced the weight loss of infected mice and lowered the bioluminescent signal of infecting meningococci. This improvement was associated with higher recruitment of inflammatory myeloid cells, such as interstitial monocytes and dendritic cells, to the lungs. Our data highlight the role of the gut-lung axis. L. paracasei CNCM I-1518 may boost the defence against IAV infection and secondary bacterial infection, which should be further studied and validated in clinical trials.

Possible biochemical impact of malaria infection in subjects with HIV co-infection in Anambra state, Nigeria.

Science.gov (United States)

Onyenekwe, C C; Ukibe, N; Meludu, S C; Ifeanyi, M; Ezeani, M; Onochie, A; Ofiaeli, N; Aboh, N; Ilika, A

2008-06-01

The present study was designed to determine possible contributory impact of malaria infection on some biochemical markers in subjects with HIV co-infection in order to know if they are adverse or protective. Participants were recruited at the Voluntary Counseling and Testing Unit, Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria and grouped into: (i) Malaria and HIV co-infection group (n = 45); and (ii) HIV infected group without concurrent malaria infection (n = 57). Standard laboratory methods were used for the HIV and Plasmodium falciparum antigen screening, malaria parasite density, CD4+ T-cell count, packed cell volume, white blood cell count, serum iron and albumin concentrations. The results showed that serum iron and albumin were significantly reduced and raised respectively in 'Malaria-HIV co-infection group' compared with 'HIV infection group' (p < 0.05 and p < 0.05). A positive association was observed between age and serum iron concentration in malaria and HIV co-infected group (r = 0.580; p < 0.05) while negative associations were observed between PCV and serum iron (r = - 0.388; p < 0.05) and between CD4+ T-cells and serum iron concentration (r = -0.362; p < 0.05) in malaria and HIV co-infected group. The CD4+ T-cell count, WBC count, PCV were not significantly different between the Malaria-HIV co-infection group and HIV infection group. In the present study serum iron and albumin concentrations were the most sensitive indicators that showed the contributory impact of malaria infection on biochemical index in HIV co-infected subjects. The findings suggest that at the defined stage of HIV infection in the present study, malaria co-infection may moderate the impact of HIV infection on iron metabolism and hepatic synthesis of albumin.

Paediatric HIV infection.

Science.gov (United States)

Scarlatti, G

1996-09-28

By the year 2000 there will be six million pregnant women and five to ten million children infected with HIV-1. Intervention strategies have been planned and in some instances already started. A timely and cost-effective strategy needs to take into account that most HIV-1 infected individuals reside in developing countries. Further studies are needed on immunological and virological factors affecting HIV-1 transmission from mother to child, on differential disease progression in affected children, and on transient infection.

Identifying HIV-1 dual infections

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Cornelissen Marion

2007-09-01

Full Text Available Abstract Transmission of human immunodeficiency virus (HIV is no exception to the phenomenon that a second, productive infection with another strain of the same virus is feasible. Experiments with RNA viruses have suggested that both coinfections (simultaneous infection with two strains of a virus and superinfections (second infection after a specific immune response to the first infecting strain has developed can result in increased fitness of the viral population. Concerns about dual infections with HIV are increasing. First, the frequent detection of superinfections seems to indicate that it will be difficult to develop a prophylactic vaccine. Second, HIV-1 superinfections have been associated with accelerated disease progression, although this is not true for all persons. In fact, superinfections have even been detected in persons controlling their HIV infections without antiretroviral therapy. Third, dual infections can give rise to recombinant viruses, which are increasingly found in the HIV-1 epidemic. Recombinants could have increased fitness over the parental strains, as in vitro models suggest, and could exhibit increased pathogenicity. Multiple drug resistant (MDR strains could recombine to produce a pan-resistant, transmittable virus. We will describe in this review what is presently known about super- and re-infection among ambient viral infections, as well as the first cases of HIV-1 superinfection, including HIV-1 triple infections. The clinical implications, the impact of the immune system, and the effect of anti-retroviral therapy will be covered, as will as the timing of HIV superinfection. The methods used to detect HIV-1 dual infections will be discussed in detail. To increase the likelihood of detecting a dual HIV-1 infection, pre-selection of patients can be done by serotyping, heteroduplex mobility assays (HMA, counting the degenerate base codes in the HIV-1 genotyping sequence, or surveying unexpected increases in the

Fungal Skin Infections

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... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... touching the infected area. Diagnosis Skin scrapings or cultures Doctors may suspect a fungal infection when they ...

C. difficile Infection

Science.gov (United States)

... Patients Home / Digestive Health Topic / C. Difficile Infection C. Difficile Infection Basics Overview Diarrhea is a frequent ... that change the normal colon bacteria allowing the C. difficile bacteria to grow and produce its toxins. ...

[Infection prevention check-in and infection prevention check-out to prevent nosocomial infections].

Science.gov (United States)

Kramer, A; Schilling, M; Heidecke, C D

2010-02-01

A precondition for the success of the prevention of SSI is the complete realisation of the proven anti-infective measures in form of the multi-barrier strategy or the so-called bundles. In daily practice it is important to follow the fixed instructions, i. e., to ensure a high compliance. In much the same way as an airline pilot or co-pilot must examine whether all instruments are functioning before each take-off, a comparable procedure should be developed as a pre-operative control for the observance of all -defined measures by the responsible surgeon and for the post-operative supervision by the patient. For the control of the observance of the defined pre-operative prevention measures, a check list with 12 items was developed, named the "infection prevention check-in". The check list is authorised by the responsible surgeon be-fore each operation. For the surveillance of the general hygiene in the post-operative period the "infection prevention check-out" with 14 items was developed. Thereby the patient is able to evaluate the staff's compliance with the hygienic measures at the time of dismissal. With the introduction of the check-lists a simple means is given to involve both the team of the surgeons and the ward staff, together with the patient, into the infection prophylaxis even more effectively. In order to assess the success of those measures, the influence on the rate of SSI is to be determined prospectively. Georg Thieme Verlag Stuttgart, New York.

Risk of Zika virus transmission in the Euro-Mediterranean area and the added value of building preparedness to arboviral threats from a One Health perspective.

Science.gov (United States)

Escadafal, Camille; Gaayeb, Lobna; Riccardo, Flavia; Pérez-Ramírez, Elisa; Picard, Marie; Dente, Maria Grazia; Fernández-Pinero, Jovita; Manuguerra, Jean-Claude; Jiménez-Clavero, Miguel-Ángel; Declich, Silvia; Victoir, Kathleen; Robert, Vincent

2016-12-03

In the alarming context of risk of Zika virus (ZIKV) transmission in the Euro-Mediterranean area, there is a need to examine whether capacities to detect, diagnose and notify ZIKV infections in the region are in place and whether ongoing capacity-building initiatives are filling existing gaps.The MediLabSecure network, created in 2014, comprises 55 laboratories of virology and medical entomology and 19 public health institutions in 19 countries in the Balkans, North-Africa, the Middle-East and the Black Sea regions. It aims to set up awareness, risk assessment, monitoring and control of emerging and re-emerging vector-borne viruses. We here examine the actions and strategies that MediLabSecure has been implementing and how they will contribute to the prevention and control of the ZIKV threat in the Euro-Mediterranean area.Capacity-building for arbovirus diagnostics is a major objective of the project and follows a methodological rather than disease-driven approach. This enables the implementation of laboratory trainings on techniques that are common to several arboviruses, including ZIKV, and putting into action appropriate diagnostic tools in the target region.Moreover, by its One Health approach and the interaction of its four sub-networks in human virology, animal virology, medical entomology and public health, MediLabSecure is fostering intersectoral collaboration, expertise and sharing of information. The resulting exchanges (methodological, communication and operational) across disciplines and across countries, dedicated research on intersectoral collaboration and increasing diagnostic capacities are providing new paths and tools to public health professionals to face emerging viral threats such as a ZIKV epidemic in the Euro-Mediterranean region.

Risk of Zika virus transmission in the Euro-Mediterranean area and the added value of building preparedness to arboviral threats from a One Health perspective

Directory of Open Access Journals (Sweden)

Camille Escadafal

2016-12-01

Full Text Available Abstract In the alarming context of risk of Zika virus (ZIKV transmission in the Euro-Mediterranean area, there is a need to examine whether capacities to detect, diagnose and notify ZIKV infections in the region are in place and whether ongoing capacity-building initiatives are filling existing gaps. The MediLabSecure network, created in 2014, comprises 55 laboratories of virology and medical entomology and 19 public health institutions in 19 countries in the Balkans, North-Africa, the Middle-East and the Black Sea regions. It aims to set up awareness, risk assessment, monitoring and control of emerging and re-emerging vector-borne viruses. We here examine the actions and strategies that MediLabSecure has been implementing and how they will contribute to the prevention and control of the ZIKV threat in the Euro-Mediterranean area. Capacity-building for arbovirus diagnostics is a major objective of the project and follows a methodological rather than disease-driven approach. This enables the implementation of laboratory trainings on techniques that are common to several arboviruses, including ZIKV, and putting into action appropriate diagnostic tools in the target region. Moreover, by its One Health approach and the interaction of its four sub-networks in human virology, animal virology, medical entomology and public health, MediLabSecure is fostering intersectoral collaboration, expertise and sharing of information. The resulting exchanges (methodological, communication and operational across disciplines and across countries, dedicated research on intersectoral collaboration and increasing diagnostic capacities are providing new paths and tools to public health professionals to face emerging viral threats such as a ZIKV epidemic in the Euro-Mediterranean region.

Influence of staff infection control training on infection-related quality measures in US nursing homes.

Science.gov (United States)

Kaur, Jasjit; Stone, Patricia W; Travers, Jasmine L; Cohen, Catherine C; Herzig, Carolyn T A

2017-09-01

Health care-associated infections are a leading cause of morbidity and mortality in US nursing home residents. Ongoing training of nursing home staff is vital to the implementation of infection prevention and control processes. Our aim was to describe associations between methods, frequency, and timing of staff infection prevention and control training and infection-related quality measures. In this national survey of nursing homes, timing of staff infection prevention and control training was associated with reduced indwelling urinary catheter use. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Cerebro-meningeal infections in HIV-infected patients: a study of ...

African Journals Online (AJOL)

Background: Cerebro-meningeal pathology is common in human immunodeficiency virus (HIV) infection and the aetiology is often difficult to ascertain with certainty. Objective: To describe the major suspected and identified causes of meningeal or encephalitic syndromes in HIV infection in Libreville, Gabon. Methods: A ...

Characterization of Cytomegalovirus Lung Infection in Non-HIV Infected Children

Directory of Open Access Journals (Sweden)

Sonia M. Restrepo-Gualteros

2014-05-01

Full Text Available Cytomegalovirus (CMV is a prevalent pathogen in the immunocompromised host and invasive pneumonia is a feared complication of the virus in this population. In this pediatric case series we characterized CMV lung infection in 15 non-HIV infected children (median age 3 years; IQR 0.2–4.9 years, using current molecular and imaging diagnostic modalities, in combination with respiratory signs and symptoms. The most prominent clinical and laboratory findings included cough (100%, hypoxemia (100%, diffuse adventitious breath sounds (100% and increased respiratory effort (93%. All patients had abnormal lung images characterized by ground glass opacity/consolidation in 80% of cases. CMV was detected in the lung either by CMV PCR in bronchoalveolar lavage (82% detection rate or histology/immunohistochemistry in lung biopsy (100% detection rate. CMV caused respiratory failure in 47% of children infected and the overall mortality rate was 13.3%. Conclusion: CMV pneumonia is a potential lethal disease in non-HIV infected children that requires a high-index of suspicion. Common clinical and radiological patterns such as hypoxemia, diffuse adventitious lung sounds and ground-glass pulmonary opacities may allow early identification of CMV lung infection in the pediatric population, which may lead to prompt initiation of antiviral therapy and better clinical outcomes.

Infections following epidural catheterization

DEFF Research Database (Denmark)

Holt, MS; Andersen, SS; Andersen, Ove

1995-01-01

of central nervous system infection of at least 0.7% at Odense University Hospital. This degree of infection is of the same magnitude as that reported for intravascular devices. We found that the patients with generalized symptoms of infection had been catheterized for a longer time, and were older than...

Acute Sleep Deprivation Enhances Post-Infection Sleep and Promotes Survival during Bacterial Infection in Drosophila

Science.gov (United States)

Kuo, Tzu-Hsing; Williams, Julie A.

2014-01-01

Study Objectives: Sleep is known to increase as an acute response to infection. However, the function of this behavioral response in host defense is not well understood. To address this problem, we evaluated the effect of acute sleep deprivation on post-infection sleep and immune function in Drosophila. Setting: Laboratory. Participants: Drosophila melanogaster. Methods and Results: Flies were subjected to sleep deprivation before (early DEP) or after (late DEP) bacterial infection. Relative to a non-deprived control, flies subjected to early DEP had enhanced sleep after infection as well as increased bacterial clearance and survival outcome. Flies subjected to late DEP experienced enhanced sleep following the deprivation period, and showed a modest improvement in survival outcome. Continuous DEP (early and late DEP) throughout infection also enhanced sleep later during infection and improved survival. However, improved survival in flies subjected to late or continuous DEP did not occur until after flies had experienced sleep. During infection, both early and late DEP enhanced NFκB transcriptional activity as measured by a luciferase reporter (κB-luc) in living flies. Early DEP also increased NFκB activity prior to infection. Flies that were deficient in expression of either the Relish or Dif NFκB transcription factors showed normal responses to early DEP. However, the effect of early DEP on post-infection sleep and survival was abolished in double mutants, which indicates that Relish and Dif have redundant roles in this process. Conclusions: Acute sleep deprivation elevated NFκB-dependent activity, increased post-infection sleep, and improved survival during bacterial infection. Citation: Kuo TH, Williams JA. Acute sleep deprivation enhances post-infection sleep and promotes survival during bacterial infection in Drosophila. SLEEP 2014;37(5):859-869. PMID:24790264

Polypeptide synthesis in alphavirus-infected aedes albopictus cells during the establishment of persistent infection

International Nuclear Information System (INIS)

Richardson, M.A.; Boulton, R.W.; Raghow, R.S.; Dalgarno, L.

1980-01-01

Polypeptide synthesis was examined in mosquito cells during the establishment of a persistent infection with two alphaviruses, Ross River virus (RRV) and Semliki Forest virus (SFV), and in vertebrate cells cytopathically-infected with the same viruses. In Aedes albopictus cells, RRV reached peak titres at 34-48 hours p.i. At 12 hours 85 per cent of cells assayed as infected by infective centre assay; by 48 hours when persistence was established, virus production was reduced and <5 per cent of cells assayed as infected. There was not shutdown of host polypeptide synthesis during infection. Viral polypeptide synthesis was maximal between 10 and 24 hours p.i. The major viral polypeptides labelled were nucleocapsid protein and envelope protein(s).The precursor polypeptide p95 which was prominent in infected BHK cells was not detected in mosquito cells. Similar results were obtained on SFV infection. During the establishment of persistence there was a coordinate decline in the synthesis of RRV polypeptides, reaching undetectable levels by 72 hours p.i. Subculturing persistently-infected cells led to a small increase in viral polypeptide synthesis and virus titre. In contrast, during RRV growth in BHK cells host protein synthesis was severely inhibited and by 9-11 hours p.i. virus-specific polypeptide synthesis represented more than 90 per cent of total protein synthetic activity. (author)

Blastocytosis hominis Infection

Science.gov (United States)

... increases in places with inadequate sanitation and poor personal hygiene. Risk factors Blastocystis is common, and anyone can ... you have blastocystis or another gastrointestinal infection, good personal hygiene can help keep you from spreading the infection ...

Infection with Hepatitis C Virus among HIV-Infected Pregnant Women in Thailand

Directory of Open Access Journals (Sweden)

Denise J. Jamieson

2008-01-01

Full Text Available Objective. The purpose of this study was to describe the epidemiology of coinfection with hepatitis C virus (HCV and HIV among a cohort of pregnant Thai women. Methods. Samples from 1771 pregnant women enrolled in three vertical transmission of HIV studies in Bangkok, Thailand, were tested for HCV. Results. Among HIV-infected pregnant women, HCV seroprevelance was 3.8% and the active HCV infection rate was 3.0%. Among HIV-uninfected pregnant women, 0.3% were HCV-infected. Intravenous drug use by the woman was the factor most strongly associated with HCV seropositivity. Among 48 infants tested for HCV who were born to HIV/HCV coinfected women, two infants were HCV infected for an HCV transmission rate of 4.2% (95% 0.51–14.25%. Conclusions. HCV seroprevalence and perinatal transmission rates were low among this Thai cohort of HIV-infected pregnant women.

Serodiagnosis of dengue infection using rapid immuno chromatography test in patients with probable dengue infection

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Kidwai, A.A.; Jamal, Q.; Mehrunnisa, S.; Farooqi, F.R.

2010-01-01

Objective: To determine the frequency of seropositive dengue infection using rapid immuno chromatographic assay in patients with probable dengue infection as per WHO criteria. Method: A cross-sectional observational study was conducted at Abbasi Shaheed Hospital, Karachi from July 2008 to January 2009. Patients presenting with acute febrile illness, rashes, bleeding tendencies, leucopenia and or thrombocytopenia were evaluated according to WHO criteria for probable dengue infection. Acute phase sera were collected after 5 days of the onset of fever as per WHO criteria. Serology was performed using rapid immuno chromatographic (ICT) assay with differential detection of IgM and IgG. A primary dengue infection was defined by a positive IgM band and a negative IgG band whereas secondary infection was defined by a positive IgG band with or without positive IgM band. Result: Among 599 patients who met the WHO criteria for dengue infection, 251(41.9%) were found to be ICT reactive among whom 42 (16.73%) had primary infection. Secondary infection was reported in 209 (83.26%). Acute phase sera of 348 (58.09%) were ICT non reactive. Four patients died because of dengue shock syndrome among which three had secondary infection. Conclusion: Early identification of secondary infection in acute phase sera using rapid ICT is valuable in terms of disease progression and mortality. However in highly suspected cases of dengue infection clinical management should not rely on negative serological results. (author)

The course of hepatitis E virus infection in pigs after contact-infection and intravenous inoculation

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de Jong Mart CM

2009-02-01

Full Text Available Abstract Background Worldwide, hepatitis E virus (HEV genotype 3 is observed in pigs and transmission to humans is implied. To be able to estimate public health risks from e.g. contact with pigs or consumption of pork products, the transmission routes and dynamics of infection should be identified. Hence, the course of HEV-infection in naturally infected pigs should be studied. Results To resemble natural transmission, 24 HEV-susceptible pigs were infected either by one-to-one exposure to intravenously inoculated pigs (C1-pigs; n = 10, by one-to-one exposure to contact-infected pigs (C2-pigs: n = 7; C3-pigs: n = 5 or due to an unknown non-intravenous infection route (one C2-pig and one C3-pig. The course of HEV-infection for contact-infected pigs was characterized by: faecal HEV RNA excretion that started at day 7 (95% confidence interval: 5–10 postexposure and lasted 23 (19–28 days; viremia that started after 13 (8–17 days of faecal HEV RNA excretion and lasted 11 (8–13 days; antibody development that was detected after 13 (10–16 days of faecal HEV RNA excretion. The time until onset of faecal HEV RNA excretion and onset of viremia was significantly shorter for iv-pigs compared to contact-infected pigs, whereas the duration of faecal HEV RNA excretion was significantly longer. At 28 days postinfection HEV RNA was detected less frequently in organs of contact-infected pigs compared to iv-pigs. For contact-infected pigs, HEV RNA was detected in 20 of 39 muscle samples that were proxies for pork at retail and in 4 of 7 urine samples. Conclusion The course of infection differed between infection routes, suggesting that contact-infection could be a better model for natural transmission than iv inoculation. Urine and meat were identified as possible HEV-sources for pig-to-pig and pig-to-human HEV transmission.

HPV Infection in Men

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Joel M. Palefsky

2007-01-01

Full Text Available While much is known about the natural history of cervical human papillomavirus (HPV infection and its consequences, including cervical intraepithelial neoplasia and cervical cancer, relatively little is known about the natural history of anogenital HPV infection and diseases in men. In part this reflects difficulties in penile sampling and visual assessment of penile lesions. Anal HPV infection and disease also remain poorly understood. Although HPV is transmitted sexually and infects the genitals of both sexes, the cervix remains biologically more vulnerable to malignant transformation than does the penis or anus in men. An understanding of male HPV infection is therefore important in terms of reducing transmission of HPV to women and improving women's health. However, it is also important due to the burden of disease in men, who may develop both penile and anal cancer, particularly among HIV-positive men who have sex with men. Improved sampling techniques of the male genitalia and cohort studies in progress should provide important information on the natural history of anogenital HPV infection and disease in men, including risk factors for HPV acquisition and transmission. The impact of HPV vaccination in women on male anogenital HPV infection will also need to be assessed.

Analysis of the T Cell Response to Zika Virus and Identification of a Novel CD8+ T Cell Epitope in Immunocompetent Mice.

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Ryan D Pardy

2017-02-01

Full Text Available Zika virus (ZIKV is an emerging arbovirus of the Flaviviridae family. Although ZIKV infection is typically mild and self-limiting in healthy adults, infection has been associated with neurological symptoms such as Guillain-Barré syndrome, and a causal link has been established between fetal microcephaly and ZIKV infection during pregnancy. These risks, and the magnitude of the ongoing ZIKV pandemic, have created an urgent need for the development of animal models to study the immune response to ZIKV infection. Previous animal models have primarily focused on pathogenesis in immunocompromised mice. In this study, we provide a model of ZIKV infection in wild-type immunocompetent C57BL/6 mice, and have provided an analysis of the immune response to infection. We evaluated the activation of several innate immune cell types, and studied the kinetics, phenotype, and functionality of T cell responses to ZIKV infection. Our results demonstrate that ZIKV infection is mild in wild-type immunocompetent C57BL/6 mice, resulting in minimal morbidity. Our data establish that at the peak of the adaptive response, antigen-experienced CD4+ T cells polarize to a Th1 phenotype, and antigen-experienced CD8+ T cells exhibit an activated effector phenotype, producing both effector cytokines and cytolytic molecules. Furthermore, we have identified a novel ZIKV CD8+ T cell epitope in the envelope protein that is recognized by the majority of responding cells. Our model provides an important reference point that will help dissect the impact of polymorphisms in the circulating ZIKV strains on the immune response and ZIKV pathogenesis. In addition, the identification of a ZIKV epitope will allow for the design of tetramers to study epitope-specific T cell responses, and will have important implications for the design and development of ZIKV vaccine strategies.