Precipitation, Climate Change, and Parasitism of Prairie Dogs by Fleas that Transmit Plague.

Science.gov (United States)

Eads, David A; Hoogland, John L

2017-08-01

Fleas (Insecta: Siphonaptera) are hematophagous ectoparasites that can reduce the fitness of vertebrate hosts. Laboratory populations of fleas decline under dry conditions, implying that populations of fleas will also decline when precipitation is scarce under natural conditions. If precipitation and hence vegetative production are reduced, however, then herbivorous hosts might suffer declines in body condition and have weakened defenses against fleas, so that fleas will increase in abundance. We tested these competing hypotheses using information from 23 yr of research on 3 species of colonial prairie dogs in the western United States: Gunnison's prairie dog (Cynomys gunnisoni, 1989-1994), Utah prairie dog (Cynomys parvidens, 1996-2005), and white-tailed prairie dog (Cynomys leucurus, 2006-2012). For all 3 species, flea-counts per individual varied inversely with the number of days in the prior growing season with >10 mm of precipitation, an index of the number of precipitation events that might have caused a substantial, prolonged increase in soil moisture and vegetative production. Flea-counts per Utah prairie dog also varied inversely with cumulative precipitation of the prior growing season. Furthermore, flea-counts per Gunnison's and white-tailed prairie dog varied inversely with cumulative precipitation of the just-completed January and February. These results complement research on black-tailed prairie dog (Cynomys ludovicianus) and might have important ramifications for plague, a bacterial disease transmitted by fleas that devastates populations of prairie dogs. In particular, our results might help to explain why, at some colonies, epizootics of plague, which can kill >95% of prairie dogs, are more likely to occur during or shortly after periods of reduced precipitation. Climate change is projected to increase the frequency of droughts in the grasslands of western North America. If so, then climate change might affect the occurrence of plague epizootics

Detection of Rickettsia felis, Rickettsia typhi, Bartonella Species and Yersinia pestis in Fleas (Siphonaptera) from Africa.

Science.gov (United States)

Leulmi, Hamza; Socolovschi, Cristina; Laudisoit, Anne; Houemenou, Gualbert; Davoust, Bernard; Bitam, Idir; Raoult, Didier; Parola, Philippe

2014-10-01

Little is known about the presence/absence and prevalence of Rickettsia spp, Bartonella spp. and Yersinia pestis in domestic and urban flea populations in tropical and subtropical African countries. Fleas collected in Benin, the United Republic of Tanzania and the Democratic Republic of the Congo were investigated for the presence and identity of Rickettsia spp., Bartonella spp. and Yersinia pestis using two qPCR systems or qPCR and standard PCR. In Xenopsylla cheopis fleas collected from Cotonou (Benin), Rickettsia typhi was detected in 1% (2/199), and an uncultured Bartonella sp. was detected in 34.7% (69/199). In the Lushoto district (United Republic of Tanzania), R. typhi DNA was detected in 10% (2/20) of Xenopsylla brasiliensis, and Rickettsia felis was detected in 65% (13/20) of Ctenocephalides felis strongylus, 71.4% (5/7) of Ctenocephalides canis and 25% (5/20) of Ctenophthalmus calceatus calceatus. In the Democratic Republic of the Congo, R. felis was detected in 56.5% (13/23) of Ct. f. felis from Kinshasa, in 26.3% (10/38) of Ct. f. felis and 9% (1/11) of Leptopsylla aethiopica aethiopica from Ituri district and in 19.2% (5/26) of Ct. f. strongylus and 4.7% (1/21) of Echidnophaga gallinacea. Bartonella sp. was also detected in 36.3% (4/11) of L. a. aethiopica. Finally, in Ituri, Y. pestis DNA was detected in 3.8% (1/26) of Ct. f. strongylus and 10% (3/30) of Pulex irritans from the villages of Wanyale and Zaa. Most flea-borne infections are neglected diseases which should be monitored systematically in domestic rural and urban human populations to assess their epidemiological and clinical relevance. Finally, the presence of Y. pestis DNA in fleas captured in households was unexpected and raises a series of questions regarding the role of free fleas in the transmission of plague in rural Africa, especially in remote areas where the flea density in houses is high.

Xenopsylla spp. (Siphonaptera: Pulicidae) in murid rodents from the Canary Islands: an update.

Science.gov (United States)

Sánchez, S; Gómez, M S

2012-11-01

The geographical and host distributions of Xenopsylla fleas parasitizing murid rodents on the Canary Islands have been reported. Three Xenopsylla species, X. cheopis, X. brasiliensis and X. guancha, have been detected on two rodents species, Mus musculus and Rattus rattus. X. guancha has been the most prevalent species detected, specifically on M. musculus, the most abundant rodent, but it has been detected only on three eastern islands, where the species is endemic. X. cheopis has been shown to be the most widely distributed species throughout the archipelago and the species most frequently found on R. rattus. X. brasiliensis has been shown to be the least prevalent Xenopsylla species, with the lowest geographical distribution on the Canary Islands and focused only on R. rattus. The detection of both X. cheopis and X. brasiliensis on the island of Lanzarote, and of X. guancha on the island of Fuerteventura and the islet of La Graciosa represents the first report of these species on those particular Canary Islands.

Xenopsylla spp. (Siphonaptera: Pulicidae in murid rodents from the Canary Islands: An update

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Sánchez S.

2012-11-01

Full Text Available The geographical and host distributions of Xenopsylla fleas parasitizing murid rodents on the Canary Islands have been reported. Three Xenopsylla species, X. cheopis, X. brasiliensis and X. guancha, have been detected on two rodents species, Mus musculus and Rattus rattus. X. guancha has been the most prevalent species detected, specifically on M. musculus, the most abundant rodent, but it has been detected only on three eastern islands, where the species is endemic. X. cheopis has been shown to be the most widely distributed species throughout the archipelago and the species most frequently found on R. rattus. X. brasiliensis has been shown to be the least prevalent Xenopsylla species, with the lowest geographical distribution on the Canary Islands and focused only on R. rattus. The detection of both X. cheopis and X. brasiliensis on the island of Lanzarote, and of X. guancha on the island of Fuerteventura and the islet of La Graciosa represents the first report of these species on those particular Canary Islands.

Using occupancy models to investigate the prevalence of ectoparasitic vectors on hosts: an example with fleas on prairie dogs

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Eads, David A.; Biggins, Dean E.; Doherty, Paul F.; Gage, Kenneth L.; Huyvaert, Kathryn P.; Long, Dustin H.; Antolin, Michael F.

2013-01-01

Ectoparasites are often difficult to detect in the field. We developed a method that can be used with occupancy models to estimate the prevalence of ectoparasites on hosts, and to investigate factors that influence rates of ectoparasite occupancy while accounting for imperfect detection. We describe the approach using a study of fleas (Siphonaptera) on black-tailed prairie dogs (Cynomys ludovicianus). During each primary occasion (monthly trapping events), we combed a prairie dog three consecutive times to detect fleas (15 s/combing). We used robust design occupancy modeling to evaluate hypotheses for factors that might correlate with the occurrence of fleas on prairie dogs, and factors that might influence the rate at which prairie dogs are colonized by fleas. Our combing method was highly effective; dislodged fleas fell into a tub of water and could not escape, and there was an estimated 99.3% probability of detecting a flea on an occupied host when using three combings. While overall detection was high, the probability of detection was always dogs, flea occupancy was heightened in old/natural colonies of prairie dogs, and on hosts that were in poor condition. Occupancy was initially low in plots with high densities of prairie dogs, but, as the study progressed, the rate of flea colonization increased in plots with high densities of prairie dogs in particular. Our methodology can be used to improve studies of ectoparasites, especially when the probability of detection is low. Moreover, the method can be modified to investigate the co-occurrence of ectoparasite species, and community level factors such as species richness and interspecific interactions.

Description of Medwayella independencia (Siphonaptera, Stivaliidae, a new species of flea from Mindanao Island, the Philippines and their phoretic mites, and miscellaneous flea records from the Malay Archipelago

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Michael Hastriter

2014-05-01

Full Text Available Medwayella independencia, a new species of flea, is described from the tupaiid host Urogale everetti (Thomas from Mindanao Island, Philippines. Several other species of fleas are also recorded from the Philippines including a single male of Lentistivalius philippinensis Hastriter & Bush, 2013 (previously known only from two males, the bat fleas Thaumapsylla breviceps orientalis Smit and Thaumapsylla longiforceps Traub, a single unidentified female species of Macrostylophora Ewing collected from the murid Bullimus bagobos Mearns, and a pair of Medwayella robinsoni ssp. from Sundasciurus hoogstraali (Sanborn from Busuanga Island, Philippines. Representatives of Medwayella Traub, 1972 and Macrostylophora have not previously been recorded from the Philippines. A key to the male sex of Medwayella is provided. Phoretic mites of the genus Psylloglyphus (family Winterschmidtiidae were present under the abdominal sclerites of several male and female specimens of M. independencia. This is the second report of a phoretic mite on a species of Medwayella Traub. The co-evolutionary implications between phoretic mites and fleas are discussed.

Techniques of DNA-studies on prehispanic ectoparasites (Pulex sp., Pulicidae, Siphonaptera from animal mummies of the Chiribaya Culture, Southern Peru

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K Dittmar

2003-01-01

Full Text Available During a paleoparasitological survey of several animal mummies (Cavia aperea f. porcellus and Canis familiaris from Chiribaya Baja, an archaeological site in Southern Peru, an unexpected find was made. In the well preserved fur, large numbers of mummified fleas (Pulex simulans/irritansthat parasitized the animals during life were encountered. Due to the relative recent event of the host mummification and the outstanding preservation of the fleas, an attempt for the retrieval of DNA was made. A DNA extraction and sequencing protocol for archaeological ectoparasitic remains has been established, taking additional studies for tissue and protein preservation into account. Tissue preservation was assessed with transmission electron microscopy and the protein preservation was tested through the racemisation ratios of aspartic acid. Regions of the 28S rDNA gene were successfully amplified and sequenced. Further research perspectives are outlined.

First detection of Candidatus Rickettsia barbariae in the flea Vermipsylla alakurt from north-western China.

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Zhao, Shan-Shan; Li, Hong-Yu; Yin, Xiao-Ping; Liu, Zhi-Qiang; Chen, Chuang-Fu; Wang, Yuan-Zhi

2016-06-07

Vermipsylla is a genus of the family Vermipsyllidae within the order Siphonaptera of fleas. Vermipsylla alakurt is mainly distributed in alpine pastoral areas of Kazakhstan, Mongolia, China and Nepal, and infests sheep, yaks and horses, causing irritation, poor condition, anaemia and even death. However, to date, no rickettsial agents have been reported in V. alakurt. A total of 133 fleas were collected directly from the tails of three sheep flocks (n = 335) in Minfeng County, Xinjiang Uygur Autonomous Region, north-western China. Of these, 55 fleas were identified by morphological examination and molecular analysis of four loci (the ribosomal 18S and 28S rDNA genes and the mitochondrial genes cytochrome  c oxidase subunit II and elongation factor 1-alpha). Eight Rickettsia-specific gene fragments originated from seven genes: the 17-kilodalton antigen gene (17-kDa), citrate synthase gene (gltA), 16S rRNA gene (rrs), outer membrane protein A gene (ompA), surface cell antigen 1 gene (sca1), PS120 protein gene (gene D), and outer membrane protein B gene (ompB, two fragments), were used to identify the species of Rickettsia in 53 fleas. The amplified products were sequenced and included in a phylogenetic analysis to verify the taxonomic identification of the rickettsial agents. Based on morphological and molecular evidence, the flea was identified as Vermipsylla alakurt. Nine samples were positive (16.98 %, 9/53) for Rickettsia spp. The phylogenetic tree revealed that the rickettsial agents found in V. alakurt cluster with Candidatus Rickettsia barbariae. Our study suggests that: (i) V. alakurt may serve as a carrier for Candidatus R. barbariae; and (ii) Candidatus R. barbariae, previously reported in Israel, is the eighth newly discovered validated Rickettsia species in China. This finding extends our knowledge of the distribution of Candidatus R. barbariae and the profile of carriers, which not only comprise ticks but also fleas.

Primeiro registro de Rhynchopsyllus pulex (Siphonaptera: Tungidae em Nyctinomops laticaudatus (Chiroptera: Molossidae no Brasil First record of Rhynchopsyllus pulex (Siphonaptera: Tungidae in Nyctinomops laticaudatus (Chiroptera: Molossidae in Brazil

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Sílvia Gonzalez Monteiro

2005-08-01

Full Text Available Descreve-se o parasitismo de Rhynchopsyllus pulex (Siphonaptera: Tungidae em Nyctinomops laticaudatus (Chiroptera no município de Santa Maria, Rio Grande do Sul, Brasil.The parasitism of Rhynchopsyllus pulex (Siphonaptera: Tungidae is described in Nyctinomops laticaudatus (Chiroptera in the county of Santa Maria, Rio Grande do Sul, Brazil.

Atividade residual in vitro do pelo de cobertura de cães tratados com dinotefuran sobre larvas e adultos de Ctenocephalides felis felis (Bouché, 1835 (Siphonaptera: pulicidae Residual activity in vitro of treated dog's hair coat with dinotefuran on larvae and adults of Ctenocephalides felis felis (Bouché, 1835 (Siphonaptera: Pulicidae

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Thaís R. Correia

2008-12-01

Full Text Available O objetivo deste trabalho foi avaliar a atividade in vitro do resíduo em pelo de cobertura de cães tratados com dinotefuran sobre larvas e adultos de Ctenocephalides felis felis. Foram utilizadas três cadelas da Raça Beagle: a nº 1 foi tratada com uma formulação spray de dinotefuran a 0,834%, a nº 2 com uma formulação "strip-on" de dinotefuran a 30% e a nº 3 foi mantida sem tratamento. Pequenas áreas foram tricotomizadas nos dias 2, 9, 16, 23, 30, 37 e 44 após o tratamento. Para avaliação adulticida e larvicida, foram utilizados pulgas de uma colônia mantida em laboratório. Seis repetições com cada uma contendo 10 exemplares de C. f. felis, acondicionados em tubos de ensaio, da etapa correspondente foram utilizados por dia de desafio. Em cada repetição foi adicionado 0,02 gramas de pelo de cada área tricotomizada e dieta na etapa de larvas. O material da etapa adulto foi avaliado num período de 24 horas, o da etapa larvas foi avaliado após 20 dias de cada desafio. O resíduo no pêlo de cães tratados com ambas as formulações de dinotefuran foi eficaz no controle de larvas por um período de 44 dias, e no controle de adultos as formulações spray e a "strip-on" foram eficazes por um período de 16 e 23 dias, respectivamente.The aim of this study was to evaluate the residual activity of treated dog's hair coat with dinotefuran on larvae and adults of Ctenocephalides felis felis. Three female Beagle dogs were used. One female dog was treated with 0.834% dinotefuran spray, the second was treated with 30% dinotefuran strip-on and the third was not treated. Some areas of dog's hair were clipped on days 2, 9, 16, 23, 30, 37 and 44 after treatment. For the evaluation of adulticidal and larvicidal activities, flea adults and larvae from the laboratory colony were used. Six repetitions were used with 10 samples of each flea stage per day, placed in assay tubes. In each repetition we added 0.02 g of treated or untreated dog

Occurrence of ectoparasitic arthropods associated with rodents in Hail region northern Saudi Arabia.

Science.gov (United States)

Asiry, Khalid A; Fetoh, Badr El-Sabah A

2014-09-01

Ectoparasitic arthropods are a diverse element of the Saudi fauna. Due to this, a survey of ectoparasites associated with rodents was conducted as a preliminary study in five districts of Hail region of northern Saudi Arabia for the first time. Ectoparasites extracted from 750 rodents were sampled and identified by recording their frequency of appearance. Results revealed that 1,287 ectoparasites infested 316 of the captured rodent hosts. These ectoparasites parasitized on four species of rodents including three species of rats Rattus rattus rattus, Rattus rattus frugivorus, and Rattus rattus alexandrinus and one species of mouse Acomys dimidiatus (Rodentia: Muridae). The ectoparasites belong to four different groups: ticks, fleas, lice, and mites. Ticks were the highest in the number, while fleas were the lowest among all the extracted ectoparasite groups. The collected ectoparasitic arthropods consisted of seven species. Ticks were of two species: Rhipicephalus turanicus and Rhipicephalus sanguineus (Acari: Ixodidae), fleas were of two species: Xenopsylla cheopis and Xenopsyllus conformis mycerini (Siphonaptera: Pulicidae), lice was a single species: Polyplax serrata (Anoplura: Hoplopleuridae), and mites were of two species: Laelaps nuttali and Laelaps echidninus (Mesostigmata: Laelapidae). The findings of the study showed that the intensity of infestation was varied between rodent host sexes, wherein females had the highest rate of parasitic infestation, and the parasitic index of appearance was very high for one group of parasites (i.e., ticks). The parasitic prevalence was 42.13 % on rodents, and mites were the most prevalent parasite species. Overall, this study was carried out to establish baseline data for ectoparasite-infested rodents in Hail region, Saudi Arabia, and may help for appropriate planning to control zoonotic diseases in this area.

New record of a phoretic flea associated with earwigs (Dermaptera, Arixeniidae) and a redescription of the bat flea Lagaropsylla signata (Siphonaptera, Ischnopsyllidae)

OpenAIRE

Hastriter,Michael; Miller,Kelly; Svenson,Gavin; Whiting,Michael F.; Whiting,Michael

2017-01-01

Abstract Lagaropsylla signata (Wahlgren, 1903), previously known only from the Island of Java, Indonesia is redescribed and reported for the first time in Deer Cave, Gunung Mulu National Park, Sarawak, Malaysia (west coast of Borneo). Many were found clinging to the earwig Arixenia esau Jordan, 1909. A similar account of a phoretic flea ( Lagaropsylla turba Smit, 1958) on the same species of cave-dwelling earwig has been reported in peninsular Malaysia in a well-documented association with th...

Fleas

Science.gov (United States)

... small insects that feed on the blood of humans, dogs, cats, and other warm-blooded animals. ... Fleas prefer to live on dogs and cats. They may also be found on ... not be bothered by fleas until their pet has been gone for a ...

Fleas and flea control

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Dautović Živomir

2002-01-01

Full Text Available Fleas as hemeatophagous arthropodes take part in the spreading of certain diseases such as bubonic plague, murine typhus, tick-borne typhus tularaemia, or can be transitory hosts for certain species of cestodes for dogs and cats. Depending on the type of host on which fleas persist and the habitat, measures that can be taken to control them can be only sanitary-hygiene, individual, or treatment of the habitat. Sanitary-hygiene measures mostly consist of regular cleaning. Individual protection implies the use of insecticides for re-impregnating clothing, spraying clothing and the use of repellents. Treatment of habitats comprises the use of insecticides of the group of organophosphates, metyl-carbamates, pyrethroids and organo-chlorine compounds, instruments for dusting and spraying. In addition to these compounds, preparations based on imidaclopride, fipronyl and inhibitors of insect growth (IGRs and development (IDIs are also used. Flea control in household pets is implemented using measures of individual protection and treatment of their habitats.

External parasites of raptors (Falconiformes and Strigiformes): identification in an ex situ population from Mexico.

Science.gov (United States)

de Oliveira, Jaqueline B; Santos, Tiziano; Vaughan, Christopher; Santiago, Heber

2011-09-01

Raptorial birds harbor a variety of ectoparasites and the mayority of them are host specific. The aim of this study was to identify the ectoparasites of captive birds of prey from Mexico, as well as to verify their impact in the health of infested birds. Raptorial birds were confiscated and kept in captivity at the Centro de Investigación y Conservación de Vida Silvestre (CIVS) in Los Reyes La Paz, Mexico State. Seventy-four birds of prey (66 Falconiformes and eigth Strigiformes) of 15 species were examined for the presence of ectoparasites. We examined both juvenile and adult birds from both sexes. The overall prevalence was 16.2%; 66.7% of raptors were infested with a single type of external parasite. Lice were the most prevalent ectoparasites (91.7%), followed by feather mites and fleas (8.3%). Degeeriella fulva (72.7%), Craspedorrhynchus sp. (45.4%) and Strigiphilus aitkeni (9.1%) (Ischnocera, Philopteridae) were recovered from wings, head and neck regions of red-tailed hawk (Buteo jamaicensis), Swainson's hawk (B. swainsoni), Harris's hawk (Parabuteo unicinctus) and Barn owl (Tyto alba). Low lice infestation level was observed. Nymphs and females of feather mites Kramerella sp. (Pterolichoidea, Kramerellidae) were recovered solely from Barn owl (T. alba); while one Caracara (Caracara cheriway) was infested by the sticktight flea Echidnophaga gallinacea (Siphonaptera, Pulicidae). No clinical signs were observed in any infested bird. Probably the periodic use of organophosphorates was responsible of the low prevalence and lice infestation levels. The diversity of external parasites illustrates the importance of detailed revision of incoming and long-term captive raptors as part of responsible captive management. Five new hosts and geographic records are presented.

Revision of fleas of the genus Plocopsylla belonging to the 'angusticeps-lewisi' complex in the Andean biogeographic region, with the description of a new species.

Science.gov (United States)

Sanchez, J; Beaucournu, J-C; Lareschi, M

2015-06-01

In Argentina, the Andean biogeographic region accommodates the most diverse population of fleas in the country. The Craneopsyllinae (Siphonaptera: Stephanocircidae) represent one of the most commonly found subfamilies in this region and show some endemism and high diversity. Plocopsylla is the most diverse genus of Craneopsyllinae; it includes 10 species mainly distributed in the Patagonian subregion, which parasitize sigmodontine rodents (Rodentia: Cricetidae). We describe and illustrate the morphology of the aedeagus in species of Plocopsylla that belong to the 'angusticeps-lewisi' complex. This character is of diagnostic value in differentiating among species. A new species of this complex, Plocopsylla (Plocopsylla) linardii sp. n., is described and identified by the shape and chaetotaxy of the distal arm of sternite IX, as well as by the shape of the median dorsal lobe of the aedeagus. New host associations for this complex and range extensions for most of its species are reported. Plocopsylla (P.) silewi is recorded for the first time in Argentina. The southern limits of the distributions of Plocopsylla (P.) lewisi and Plocopsylla (P.) wilesi are extended to Santa Cruz Province. The angusticeps-lewisi complex is found for the first time in San Juan Province. The information may be useful in epidemiological studies of flea-borne diseases. © 2015 The Royal Entomological Society.

External parasites of raptors (Falconiformes and Strigiformes: identification in an ex situ population from Mexico

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JaquelineB de Oliveira

2011-09-01

Full Text Available Raptorial birds harbor a variety of ectoparasites and the mayority of them are host specific. The aim of this study was to identify the ectoparasites of captive birds of prey from Mexico, as well as to verify their impact in the health of infested birds. Raptorial birds were confiscated and kept in captivity at the Centro de Investigación y Conservación de Vida Silvestre (CIVS in Los Reyes La Paz, Mexico State. Seventy-four birds of prey (66 Falconiformes and eigth Strigiformes of 15 species were examined for the presence of ectoparasites. We examined both juvenile and adult birds from both sexes. The overall prevalence was 16.2%; 66.7% of raptors were infested with a single type of external parasite. Lice were the most prevalent ectoparasites (91.7%, followed by feather mites and fleas (8.3%. Degeeriella fulva (72.7%, Craspedorrhynchus sp. (45.4% and Strigiphilus aitkeni (9.1% (Ischnocera, Philopteridae were recovered from wings, head and neck regions of red-tailed hawk (Buteo jamaicensis, Swainson’s hawk (B. swainsoni, Harris’s hawk (Parabuteo unicinctus and Barn owl (Tyto alba. Low lice infestation level was observed. Nymphs and females of feather mites Kramerella sp. (Pterolichoidea, Kramerellidae were recovered solely from Barn owl (T. alba; while one Caracara (Caracara cheriway was infested by the sticktight flea Echidnophaga gallinacea (Siphonaptera, Pulicidae. No clinical signs were observed in any infested bird. Probably the periodic use of organophosphorates was responsible of the low prevalence and lice infestation levels. The diversity of external parasites illustrates the importance of detailed revision of incoming and long-term captive raptors as part of responsible captive management. Five new hosts and geographic records are presented. Rev. Biol. Trop. 59 (3: 1257-1264. Epub 2011 September 01.

Fleas on wild birds in Costa Rica

Czech Academy of Sciences Publication Activity Database

Acosta, R.; Literák, I.; Sychra, O.; Čapek, Miroslav

2013-01-01

Roč. 115, č. 1 (2013), s. 1-8 ISSN 0013-8797 R&D Projects: GA AV ČR IAA601690901 Institutional support: RVO:68081766 Keywords : Ceratophyllus * Dasypsyllus * Plusaetis * Siphonaptera Subject RIV: EG - Zoology Impact factor: 0.479, year: 2013

Detection of Rickettsia Species in Fleas Collected from Cats in Regions Endemic and Nonendemic for Flea-Borne Rickettsioses in California.

Science.gov (United States)

Billeter, Sarah A; Diniz, Pedro Paulo Vissotto de Paiva; Jett, Lindsey A; Wournell, Andrea L; Kjemtrup, Anne M; Padgett, Kerry A; Yoshimizu, Melissa Hardstone; Metzger, Marco E; Barr, Margaret C

2016-03-01

Rickettsia typhi, transmitted by rat fleas, causes most human flea-borne rickettsioses worldwide. Another rickettsia, Rickettsia felis, found in cat fleas, Ctenocephalides felis, has also been implicated as a potential human pathogen. In the continental United States, human cases of flea-borne rickettsioses are reported primarily from the southern regions of Texas and California where the cat flea is considered the principal vector. In California, more than 90% of locally acquired human cases are reported from suburban communities within Los Angeles and Orange counties despite the almost ubiquitous presence of cat fleas and their hosts throughout the state. The objective of this study is to assess the presence and infection rate of Rickettsia species in cat fleas from selected endemic and nonendemic regions of California. Cat fleas were collected from cats in Los Angeles County (endemic region) and Sacramento and Contra Costa counties (nonendemic region). Sequencing of 17 amplicons confirmed the presence of R. felis in both the endemic and non-endemic regions with a calculated maximum likelihood estimation of 131 and 234 per 1000 fleas, respectively. R. typhi was not detected in any flea pools. Two R. felis-like genotypes were also detected in fleas from Los Angeles County; Genotype 1 was detected in 1 flea pool and Genotype 2 was found in 10 flea pools. Genotype 1 was also detected in a single flea pool from Sacramento County. Results from this study show that R. felis is widespread in cat flea populations in both flea-borne rickettsioses endemic and nonendemic regions of California, suggesting that a high prevalence of this bacterium in cat fleas does not predispose to increased risk of human infection. Further studies are needed to elucidate the role of R. felis and the two R. felis-like organisms as etiologic agents of human flea-borne rickettsioses in California.

Integrated morphological and molecular identification of cat fleas (Ctenocephalides felis) and dog fleas (Ctenocephalides canis) vectoring Rickettsia felis in central Europe

Czech Academy of Sciences Publication Activity Database

Lawrence, A.L.; Hii, S.-F.; Jirsová, D.; Panáková, L.; Ionică, A.M.; Gilchrist, K.; Modrý, David; Mihalca, A. D.; Webb, C.E.; Traub, R.J.; Šlapeta, J.

2015-01-01

Roč. 210, 3-4 (2015), s. 215-223 ISSN 0304-4017 Institutional support: RVO:60077344 Keywords : Arthropod * Siphonaptera * Zoonosis * Bartonella * Taxonomy * cox1 Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.242, year: 2015

Distributional data and taxonomic notes on the flea Strepsylla (Siphonaptera: Ctenophthalmidae: Neopsyllinae: Phalacropsyllini Datos de distribución y notas taxonómicas de las especies de Strepsylla (Siphonaptera: Ctenophthalmidae: Neopsyllinae: Phalacropsyllini

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Roxana Acosta

2011-12-01

Full Text Available Strepsylla Traub, 1950 is considered a New World flea genus, parasitizing, in most cases, species of Muridae, particularly peromyscines. Thirteen species of Strepsylla are addressed with respect to their taxonomic characters, host preferences and geographic distribution. A detailed list of material is included.Strepsylla Traub, 1950 es considerado un género de pulgas del nuevo mundo, que en la mayoría de los casos parasitan múridos, particularmente peromisinos. Se comentan algunos de los caracteres taxonómicos, preferencia de huéspedes, distribución geográfica y el material examinado de las 13 especies del género.

Plague and the Human Flea, Tanzania

DEFF Research Database (Denmark)

Laudisoit, Anne; Leirs, Herwig; Makundi, Rhodes H

2007-01-01

Domestic fleas were collected in 12 villages in the western Usambara Mountains in Tanzania. Of these, 7 are considered villages with high plague frequency, where human plague was recorded during at least 6 of the 17 plague seasons between 1986 and 2004. In the remaining 5 villages with low plague...... frequency, plague was either rare or unrecorded. Pulex irritans, known as the human flea, was the predominant flea species (72.4%) in houses. The density of P. irritans, but not of other domestic fleas, was significantly higher in villages with a higher plague frequency or incidence. Moreover, the P....... irritans index was strongly positively correlated with plague frequency and with the logarithmically transformed plague incidence. These observations suggest that in Lushoto District human fleas may play a role in plague epidemiology. These findings are of immediate public health relevance because...

Fleas and Flea-Associated Bartonella Species in Dogs and Cats from Peru.

Science.gov (United States)

Rizzo, M F; Billeter, S A; Osikowicz, L; Luna-Caipo, D V; Cáceres, A G; Kosoy, M

2015-11-01

In the present study, we investigated 238 fleas collected from cats and dogs in three regions of Peru (Ancash, Cajamarca, and Lima) for the presence of Bartonella DNA. Bartonella spp. were detected by amplification of the citrate synthase gene (16.4%) and the 16S-23S intergenic spacer region (20.6%). Bartonella rochalimae was the most common species detected followed by Bartonella clarridgeiae and Bartonella henselae. Our results demonstrate that dogs and cats in Peru are infested with fleas harboring zoonotic Bartonella spp. and these infected fleas could pose a disease risk for humans. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

Leptopsylla algira costai (Siphonaptera: Leptopsyllidae: New host and new geographical record

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Ali Yousefi

2016-11-01

Full Text Available Objective: To access the emerging ectoparasites associated with shrews in Hamedan Province of Iran. Methods: We have captured bicoloured white-toothed shrews [Crocidura leucodon (C. leucodon] using the live traps in April 2014. Ectoparasites collected by brushing the skins were removed and preserved in 70% ethanol containing 5% glycerin, and subsequently they were sent to the parasitology laboratory and processed. The fleas isolated from infested specimen were cleared in 10% aqueous potassium hydroxide, dehydrated in ethanol, cleared in xylene, mounted in Canada balsam and identified using reliable keys. Results: In general, eight fleas (one male, seven females were collected from C. leucodon in Hamedan Province, Western Iran. The fleas were identified as Leptopsylla algira costai Smit, 1955. Conclusions: Fleas are medically important because they transmit a wide variety of diseases to their hosts. In addition, this aricle reports Leptopsylla algira costai for the first time in new host (C. leucodon and new geographical region (Iran.

Non-equilibrium dog-flea model

Science.gov (United States)

Ackerson, Bruce J.

2017-11-01

We develop the open dog-flea model to serve as a check of proposed non-equilibrium theories of statistical mechanics. The model is developed in detail. Then it is applied to four recent models for non-equilibrium statistical mechanics. Comparison of the dog-flea solution with these different models allows checking claims and giving a concrete example of the theoretical models.

Rickettsia felis in fleas from Catalonia (Northeast Spain).

Science.gov (United States)

Nogueras, María-Mercedes; Pons, Immaculada; Ortuño, Anna; Lario, Sergio; Segura, Ferran

2011-05-01

Rickettsia felis produces a syndrome indistinguishable from murine typhus, which has been described in Spain. R. felis is transmitted to humans by fleas. Although no clinical case has been described so far, serologic evidence of infections in humans, cats, and dogs has been obtained in our area. However, no study has been conducted regarding its presence in vectors. Recognition of routes of transmission is of great importance to prevent infection in humans. Taking into account these results, R. felis seems to be present in animals that are in contact with humans. The aim of this study was to determine the presence of R. felis in the fleas of cats and dogs from Northeast Spain, to show the presence of peridomestic cycle in our area. Between May 2006 and July 2008, 78 fleas were collected. Sixty-three fleas were recovered from kennels. Most of them were collected from cages and a few of them on dogs and cats living in kennels. Fifteen fleas were collected from dogs and cats attended at a veterinary clinic. Fleas were rinsed with ethanol, dried, identified, and stored at 4°C. DNA was extracted from each flea individually. Rickettsial DNA was determined by quantitative real-time polymerase chain reaction. OmpB-specific primers and molecular beacon probes targeting specifically R. felis were used. All 78 fleas were identified as Ctenocephalides felis. R. felis was detected in 34 (43.6%) fleas. No nucleic acids were amplified from negative controls and expected results were obtained from positive controls. Eight positive samples were also confirmed by sequencing. R. felis was found in a high percentage of Ct. felis from cats and dogs. It seems that there is a peridomestic cycle in Northeast Spain, which would allow contact of R. felis with humans.

[Fleas on small mammals in the surrounding area of Erhai Lake].

Science.gov (United States)

Dong, Wen-Ge; Guo, Xian-Guo; Men, Xing-Yuan; Gong, Zheng-Da; Wu, Dian; Zhang, Zheng-Kun; Zhang, Li-Yun

2009-12-01

To investigate the distribution pattern, species diversity and community structure of fleas on small mammals in the surrounding area of Erhai Lake, and the relationship between fleas and their hosts. Different geographical areas surrounding the Erhai Lake in Yunnan were selected as investigated spots. Small mammals were captured with baited cages. The cage-traps were examined and re-baited each morning. All fleas on the hosts were collected and identified. The richness (S), evenness (J'), diversity index (H'), dominance index (C'), total ectoparasite infestation rate (Rpt), total ectoparasite infestation index (Ipt), and constituent ratio (Cr) were used to measure the community structure. Altogether, 3,303 small mammals and 3,243 fleas were collected. From the 21 species of small mammal hosts, 13 species of fleas were identified. In southern area of the Lake, the species richness (21 species of small mammals & 12 species of fleas) was highest among the three selected areas. Seventeen species of small mammals and 8 species of fleas were found in eastern area, and only 13 species of small mammals and 7 species of fleas found in the west. This implied the probable influences of ecological environments on the fleas and their corresponding hosts. The community structure of fleas on small mammals was complex. The species diversity, species composition, community structure and distribution pattern of fleas were simultaneously influenced by the hosts' body surface microenvironment and the macroenvironment (habitat). The fleas are commonly distributed in small mammals in the areas and their communities are related to host species and the habitats.

Monitoring laundry for fleas

International Nuclear Information System (INIS)

Cooper, T.L.; Goldin, E.M.; Warnock, R.V.

1987-01-01

The San Onofre Unit 3 nuclear plant experienced fuel cladding failures during its first fuel cycle. When primary systems were opened for maintenance and refueling, areas on site were contaminated with fleas - tiny, highly radioactive fuel fragments. While highly mobile, these fragments demonstrated an affinity to attach to some surfaces and clothing. This paper discusses the problems encountered in detecting fleas in the presence of residual activation and fission product contamination on laundered protective clothing. A novel approach to overcome those inherent problems is presented and a home-built laundry monitor utilizing off-the-shelf components is described

Human infestation by pigeon fleas (Ceratophyllus columbae) from feral pigeons.

Science.gov (United States)

Haag-Wackernagel, Daniel; Spiewak, Radosław

2004-01-01

The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus columbae) over a period of 2 months. The source of the fleas was a pair of breeding feral pigeons (Columba livia). The birds' nest was located in the attic immediately above the couple's apartment, and the fleas found their way along an unsealed heating pipe. The people encountered up to 40 bites per night. With invasions repeated almost every night, the man gradually developed an allergic urticarial reaction. The most traumatic experience for the couple, however, was to learn that they were invaded by fleas (initially, they had presumed they were bothered by mosquitoes). This information resulted in severe psychological distress with phobic reactions and insomnia. Despite the successful removal of the fleas and the pigeons that were source of the pest, parasitophobia of the man persisted over the following 4 months. This case is discussed from the broader aspect of health risks related to feral pigeons and animal fleas. Also summarised are previous observations on people invaded by pigeon fleas.

Molecular detection of Rickettsia typhi in cats and fleas.

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Maria Mercedes Nogueras

Full Text Available BACKGROUND: Rickettsiatyphi is the etiological agent of murine typhus (MT, a disease transmitted by two cycles: rat-flea-rat, and peridomestic cycle. Murine typhus is often misdiagnosed and underreported. A correct diagnosis is important because MT can cause severe illness and death. Our previous seroprevalence results pointed to presence of human R. typhi infection in our region; however, no clinical case has been reported. Although cats have been related to MT, no naturally infected cat has been described. The aim of the study is to confirm the existence of R. typhi in our location analyzing its presence in cats and fleas. METHODOLOGY/PRINCIPAL FINDINGS: 221 cats and 80 fleas were collected from Veterinary clinics, shelters, and the street (2001-2009. Variables surveyed were: date of collection, age, sex, municipality, living place, outdoor activities, demographic area, healthy status, contact with animals, and ectoparasite infestation. IgG against R. typhi were evaluated by indirect immunofluorescence assay. Molecular detection in cats and fleas was performed by real-time PCR. Cultures were performed in those cats with positive molecular detection. Statistical analysis was carried out using SPSS. A p < 0.05 was considered significant. Thirty-five (15.8% cats were seropositive. There were no significant associations among seropositivity and any variables. R. typhi was detected in 5 blood and 2 cultures. High titres and molecular detection were observed in stray cats and pets, as well as in spring and winter. All fleas were Ctenocephalides felis. R. typhi was detected in 44 fleas (55%, from shelters and pets. Co-infection with R. felis was observed. CONCLUSIONS: Although no clinical case has been described in this area, the presence of R. typhi in cats and fleas is demonstrated. Moreover, a considerable percentage of those animals lived in households. To our knowledge, this is the first time R. typhi is detected in naturally infected cats.

Rickettsia felis in cat fleas, Ctenocephalides felis parasitizing opossums, San Bernardino County, California.

Science.gov (United States)

Abramowicz, K F; Wekesa, J W; Nwadike, C N; Zambrano, M L; Karpathy, S E; Cecil, D; Burns, J; Hu, R; Eremeeva, M E

2012-12-01

Los Angeles and Orange Counties are known endemic areas for murine typhus in California; however, no recent reports of flea-borne rickettsioses are known from adjacent San Bernardino County. Sixty-five opossums (Didelphis virginiana) were trapped in the suburban residential and industrial zones of the southwestern part of San Bernardino County in 2007. Sixty out of 65 opossums were infested with fleas, primarily cat fleas, Ctenocephalides felis (Bouché, 1835). The flea minimum infection rate with Rickettsia felis was 13.3% in pooled samples and the prevalence was 23.7% in single fleas, with two gltA genotypes detected. In spite of historic records of murine typhus in this area, no evidence for circulation of R. typhi in fleas was found during the present study. Factors contributing to the absence of R. typhi in these cat fleas in contrast to its presence in cat fleas from Orange and Los Angeles Counties are unknown and need to be investigated further in San Bernardino County. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Seasonal and habitat dependence of fleas parasitic on small mammals in Tanzania

DEFF Research Database (Denmark)

Laudisoit, Anne; Leirs, Herwig; Makundi, Rhodes

2009-01-01

in both host and flea species composition varied seasonally. Despite the relatively rich mammal and flea fauna of the study region, the major contribution to variation in species composition between seasons and among habitats was due to a few species only. Flea assemblages on Lophuromys kilonzoi Verheyen...

Human infestation by pigeon fleas (Ceratophyllus columbae) from feral pigeons.

OpenAIRE

Haag-Wackernagel, D; Spiewak, R.W.

2004-01-01

The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus columbae) over a period of 2 months. The source of the fleas was a pair of breeding feral pigeons (Columba livia). The birds' nest was located in the attic immediately above the couple's apartment, and the fleas found their way along an unsealed heating pipe. The people encountered up to 40 bites per night. With invasions repeated almost every night, the man gradually developed an allergic urticari...

Detection of flea-borne Rickettsia species in the Western Himalayan region of India

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R Chahota

2015-01-01

Full Text Available Human infections by various rickettsial species are frequently reported globally. We investigated a flea-borne rickettsial outbreak infecting 300 people in Western Himalayan region of India. Arthropod vectors (ticks and fleas and animal and human blood samples from affected households were analysed by gltA and ompB genes based polymerase chain reaction (PCR. Rat flea (Ceratophyllus fasciatus samples were found harbouring a Rickettsia sp. Phylogenetic analysis based on gltA gene using PHYLIP revealed that the detected Rickettsia sp. has 100% identity with SE313 and RF2125 strains of Rickettsia sp. of flea origin from Egypt and Thai-Myanmar border, respectively and cf1 and 5 strains from fleas and lice from the USA. But, the nucleotide sequence of genetically variable gene ompB of R14 strain was found closely related to cf9 strain, reported from Ctenocephalides felis fleas. These results highlight the public health importance of such newly discovered or less recognised Rickettsia species/strains, harboured by arthropod vectors like fleas.

Five-month comparative efficacy evaluation of three ectoparasiticides against adult cat fleas (Ctenocephalides felis), flea egg hatch and emergence, and adult brown dog ticks (Rhipicephalus sanguineus sensu lato) on dogs housed outdoors.

Science.gov (United States)

Varloud, Marie; Hodgkins, Elizabeth

2015-03-01

This study was designed to compare the efficacy of three topical combinations on dogs in outdoor conditions against adult cat fleas (Ctenocephalides felis), flea egg hatch and emergence, and against adult brown dog ticks (Rhipicephalus sanguineus sensu lato). Treatment was performed on day 0 with a placebo; dinotefuran, pyriproxifen and permethrin (DPP); fipronil and (S)-methoprene (FM) or imidacloprid and permethrin (IP). Dogs (n = 32), housed outdoors for 7 months, were treated monthly for four consecutive months (on days 0, 30, 60 and 90) and infested with ~100 unfed adult fleas on days 14, 55, 74, 115 and 150 and with ~50 unfed adult ticks on days 28, 44, 88 and 104. Adult fleas were counted and removed 24 h after infestation. Immediately after flea removal, dogs were reinfested with ~100 new adult fleas 72 h prior to egg collection for up to 48 h. Flea eggs were incubated for 32 days, and newly emerged adults were counted. Ticks were counted and removed 48 h after each infestation. FM had >90 % efficacy against fleas at each time point and variable efficacy against ticks (38.0-99.6 %). Efficacy of IP was 60 days after the last treatment. Despite challenging weather conditions, DPP was highly effective, providing >90 % efficacy against adult ticks as well as adult and immature fleas at every time point of the study.

[The fleas of mammals from the Ucayali River basin (the Peruvian Amazonia)].

Science.gov (United States)

Darskaia, N F; Malygin, V M

1996-01-01

The material collected from 57 specimens of 9 mammalian species in two localities of the Peruvian Amazonia includes 212 specimens of fleas belonging to four species (Polygenis klagesi, Ropalopsyllus lugubris, Rh. australis and Rothschildopsylla noctilionis). This is the first record of fleas in the Ucayali River basin. The majority of flea specimens were collected form three morphologically similar but karyotypically and electrophoretically distinct species of spiny rats of the genus Proechimys. These fleas belong to the species P. klagesi. The subspecies P. k. samuelis was collected from 32-chromosome spiny rats nearby Pucallpa (8 degrees 22' S, 74 degrees 43' W), whereas in the locality nearby the village Jenaro Errera (4 degrees 52' S, 73 degrees 39' W) only the nominative subspecies P. k. klagesi were collected from all three species of spiny rats. Other species of fleas have relatively less abundance. Six fleas Rh. l. lugubris were found on one specimen of Cuniculus paca; a single Rh. australis--on one specimen of Myoprocta pratti; and a single R. noctilionis--on one specimen of Eptesicus brasiliensis.

FLEAS OF BLACK-FOOTED FERRETS (MUSTELA NIGRIPES) AND THEIR POTENTIAL ROLE IN THE MOVEMENT OF PLAGUE.

Science.gov (United States)

Mize, Erica L; Grassel, Shaun M; Britten, Hugh B

2017-07-01

Sylvatic plague is one of the major impediments to the recovery of the black-footed ferret ( Mustela nigripes ) because it decimates their primary prey species, prairie dogs ( Cynomys spp.), and directly causes mortality in ferrets. Fleas are the primary vector of Yersinia pestis , the causative agent of sylvatic plague. The goal of this research was to better understand the flea fauna of ferrets and the factors that might influence flea abundance on ferrets. Fleas from ferrets were tested for Y. pestis in a post hoc assessment to investigate the plausibility that some ferrets could act as incidental transporter hosts of fleas infected with Y. pestis . Fleas were collected from ferrets captured on the Lower Brule Indian Reservation in central South Dakota, US from 2009 to 2012. A total of 528 fleas collected from 67 individual ferrets were identified and tested for the presence of Y. pestis with a nested PCR assay. The predominant flea recovered from ferrets was Oropsylla hirsuta , a species that comprises 70-100% of the fleas recovered from prairie dogs and their burrows in the study area. Yersinia pestis was detected at low levels in fleas collected from ferrets with prevalence ranging from 0% to 2.9%; male ferrets harbored significantly more fleas than female ferrets. Six of 67 ferrets vaccinated against plague carried fleas that tested positive for Y. pestis , which suggests ferrets vaccinated against plague could inadvertently act as incidental transporter hosts of Y. pestis -positive fleas.

EKTOPARASIT (FLEAS PADA RESERVOIR DI DAERAH FOKUS PEST DI KABUPATEN BOYOLALI PROVINSI JAWA TENGAH

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Tri Ramadhani

2016-09-01

Full Text Available ABSTRACTRat is a rodent (rodensia which cannot be separated from parasitic organism attacks the ectoparasites(fleas. In the presence of fleas plague focus areas need to watch out, for no increase in cases of plague(outbreak. Pest is a zoonosis in rat that can be transmitted to humans through the bite of fleas Xenopsyllacheopsis containing Yersinia pestis. Boyolali District is one of the plague focus areas in Central Java. Thisstudy aims to identify the species of rats and fleas, trap succes, flea infestation in rats and flea index as anindicator of vulnerability to transmission of plague. The study is a descriptive survey with cross sectionaldesign. The population is all the rats and fleas in Boyolali district. Samples are rats and fleas that werecaught using live trap with coconut roasted and salted fish is placed inside and outside the home (each 2trap. Rat combed for fleas. The results showed the number of mouses caught were 245. There are 4 speciesrats and small mammals found in R. tanezumi, R. tiomanicus, R. exulans, N. fulvescens and S.murinus withsucces trap at 5.71%. Only 3 species and S.murinus of infected fleas. Species of flea is X. cheopis and S.cognatus. Specific flea index: Xenopsylla cheopis by 1.67; flea index cognatus Stavilus common flea indexof 0.88 and 2.55. Based on the warning system indicator about the bubonic plague spreading,which isspecific flea index of X.cheopis >1 and fleas index >2, Selo sub distric should be aware to the spreading ofbubonic plague in its area, so that it is important to carry out the controlling of rat and flea population.Keyword: ectoparasite, reservoir, fleas, plague. ABSTRAK Tikus adalah hewan mengerat (rodensiayang tidak lepas dari serangan organisme parasit yaitu ektoparasit (pinjal.Pada daerah fokus pestt keberadaan pinjal perlu diwaspadai,agar tidak terjadi peningkatan kasus pestt (KLB. Pest merupakan zoonosispada tikusyang dapat ditularkan kepada manusia melalui gigitan pinjal Xenopsylla

Dermal neutrophil, macrophage and dendritic cell responses to Yersinia pestis transmitted by fleas.

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Jeffrey G Shannon

2015-03-01

Full Text Available Yersinia pestis, the causative agent of plague, is typically transmitted by the bite of an infected flea. Many aspects of mammalian innate immune response early after Y. pestis infection remain poorly understood. A previous study by our lab showed that neutrophils are the most prominent cell type recruited to the injection site after intradermal needle inoculation of Y. pestis, suggesting that neutrophil interactions with Y. pestis may be important in bubonic plague pathogenesis. In the present study, we developed new tools allowing for intravital microscopy of Y. pestis in the dermis of an infected mouse after transmission by its natural route of infection, the bite of an infected flea. We found that uninfected flea bites typically induced minimal neutrophil recruitment. The magnitude of neutrophil response to flea-transmitted Y. pestis varied considerably and appeared to correspond to the number of bacteria deposited at the bite site. Macrophages migrated towards flea bite sites and interacted with small numbers of flea-transmitted bacteria. Consistent with a previous study, we observed minimal interaction between Y. pestis and dendritic cells; however, dendritic cells did consistently migrate towards flea bite sites containing Y. pestis. Interestingly, we often recovered viable Y. pestis from the draining lymph node (dLN 1 h after flea feeding, indicating that the migration of bacteria from the dermis to the dLN may be more rapid than previously reported. Overall, the innate cellular host responses to flea-transmitted Y. pestis differed from and were more variable than responses to needle-inoculated bacteria. This work highlights the importance of studying the interactions between fleas, Y. pestis and the mammalian host to gain a better understanding of the early events in plague pathogenesis.

Factors associated with flea infestation among the different rodent ...

African Journals Online (AJOL)

Flea infection with the bacterium, Yersinia pestis is acquired from reservoirs which include several rodents and other small mammals. In areas that are endemic of plague, reservoirs of Y. pestis and various flea vectors are responsible for perpetuating existence of the disease. The objective of this cross sectional study was to ...

A 2015 outbreak of flea-borne rickettsiosis in San Gabriel Valley, Los Angeles County, California.

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Kimberly Nelson

2018-04-01

Full Text Available Although flea-borne rickettsiosis is endemic in Los Angeles County, outbreaks are rare. In the spring of 2015 three human cases of flea-borne rickettsiosis among residents of a mobile home community (MHC prompted an investigation. Fleas were ubiquitous in common areas due to presence of flea-infested opossums and overabundant outdoor cats and dogs. The MHC was summarily abated in June 2015, and within five months, flea control and removal of animals significantly reduced the flea population. Two additional epidemiologically-linked human cases of flea-borne rickettsiosis detected at the MHC were suspected to have occurred before control efforts began. Molecular testing of 106 individual and 85 pooled cat fleas, blood and ear tissue samples from three opossums and thirteen feral cats using PCR amplification and DNA sequencing detected rickettsial DNA in 18.8% of the fleas. Seventeen percent of these cat fleas tested positive for R. felis-specific DNA compared to under two (<2 percent for Candidatus R. senegalensis-specific DNA. In addition, serological testing of 13 cats using a group-specific IgG-ELISA detected antibodies against typhus group rickettsiae and spotted fever group rickettsiae in six (46.2% and one (7.7% cat, respectively. These results indicate that cats and their fleas may have played an active role in the epidemiology of the typhus group and/or spotted fever group rickettsial disease(s in this outbreak.

Flea (Pulex simulans) infestation in captive giant anteaters (Myrmecophaga tridactyla).

Science.gov (United States)

Mutlow, Adrian G; Dryden, Michael W; Payne, Patricia A

2006-09-01

A pair of captive adult giant anteaters (Myrmecophaga tridactyla) presented heavily infested with a flea species (Pulex simulans) commonly found on Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor) in the central United States. In this case, the flea was demonstrated to have completed its entire life cycle with the anteaters as the host. A single treatment of topical imidacloprid, coupled with removal and replacement of infested bedding, was rapidly effective at controlling the infestation and no adverse effects of the drug were noted. Control of the anteater infestation also removed the flea infestation of aardvarks in the same building.

Transit through the flea vector induces a pretransmission innate immunity resistance phenotype in Yersinia pestis.

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Viveka Vadyvaloo

2010-02-01

Full Text Available Yersinia pestis, the agent of plague, is transmitted to mammals by infected fleas. Y. pestis exhibits a distinct life stage in the flea, where it grows in the form of a cohesive biofilm that promotes transmission. After transmission, the temperature shift to 37 degrees C induces many known virulence factors of Y. pestis that confer resistance to innate immunity. These factors are not produced in the low-temperature environment of the flea, however, suggesting that Y. pestis is vulnerable to the initial encounter with innate immune cells at the flea bite site. In this study, we used whole-genome microarrays to compare the Y. pestis in vivo transcriptome in infective fleas to in vitro transcriptomes in temperature-matched biofilm and planktonic cultures, and to the previously characterized in vivo gene expression profile in the rat bubo. In addition to genes involved in metabolic adaptation to the flea gut and biofilm formation, several genes with known or predicted roles in resistance to innate immunity and pathogenicity in the mammal were upregulated in the flea. Y. pestis from infected fleas were more resistant to phagocytosis by macrophages than in vitro-grown bacteria, in part attributable to a cluster of insecticidal-like toxin genes that were highly expressed only in the flea. Our results suggest that transit through the flea vector induces a phenotype that enhances survival and dissemination of Y. pestis after transmission to the mammalian host.

Human infestation by pigeon fleas (Ceratophyllus columbae) from feral pigeons.

NARCIS (Netherlands)

Haag-Wackernagel, D; Spiewak, R.W.

2004-01-01

The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus columbae) over a period of 2 months. The source of the fleas was a pair of breeding feral pigeons (Columba livia). The birds' nest was located in the attic immediately above the couple's apartment, and

Cat fleas (Ctenocephalides felis) carrying Rickettsia felis and Bartonella species in Hong Kong.

Science.gov (United States)

Šlapeta, Jan; Lawrence, Andrea; Reichel, Michael P

2018-04-01

Fleas are commonly recorded on stray as well as domestic dogs and cats in Hong Kong. Fleas can be a major cause of pruritus in dogs and cats and also vectors of potentially zoonotic bacteria in the genera Rickettsia and Bartonella. Morphological examination of 174 fleas from dogs and cats living in Hong Kong revealed only cat fleas (Ctenocephalides felis). Cytochrome c oxidase subunit 1 gene (cox1) genotyping of 20 randomly selected specimens, revealed three cox1 haplotypes (HK-h1 to HK-h3). The most common haplotype was HK-h1 with 17 specimens (17/20, 85%). HK-h1 was identical to cox1 sequences of fleas in Thailand and Fiji. HK-h1 and HK-h2 form a distinct cat flea cox1 clade previously recognized as the Clade 3. HK-h3 forms a new Clade 6. A multiplex Bartonella and Rickettsia real-time PCR of DNA from 20 C. felis found Bartonella and Rickettsia DNA in three (15%) and ten (50%) C. felis, respectively. DNA sequencing confirmed the presence of R. felis, B. clarridgeiae and Bartonella henselae. This is the first reported study of that kind in Hong Kong, and further work is required to expand the survey of companion animals in the geographical region. The sampling of fleas on domestic cats and dogs in Hong Kong revealed them to be exclusively infested by the cat flea and to be harbouring pathogens of zoonotic potential. Copyright © 2017 Elsevier B.V. All rights reserved.

[Fleas community in introduced Siberian chipmunks (Tamias sibiricus Laxmann) in Forest of Sénart, France].

Science.gov (United States)

Pisanu, B; Marmet, J; Beaucournu, J C; Chapuis, J L

2008-03-01

We examined the fleas community in an introduced population of Siberian chipmunks, Tamias sibiricus, between 2005 and 2007, in the Forest of Sénart (Essonne, France). We collected and identified 383 fleas on 463 chipmunks (total: 1,891 captures on 471 chipmunks). In 2005, 120 fleas were also collected on 65 bank voles, Clethrionomys glareolus, and on 25 wood mice, Apodemus sylvaticus, trapped within the same area. Ceratophyllus sciurorum sciurorum formed 73.6% of the chipmunks' flea community, with an annual prevalence (P) ranging between 8 and 13% and a mean intensity (I) ranging between 1.1 and 1.6 fleas per individual. Among the six other species infecting this Sciurid, Ctenophthalmus agyrtes impavidus constituted 17.2% (P: 1.6-2.2%; I: 1.1-2.6), and Megabothris turbidus 8.1% (P: 0.8-1.9%; I: 1.0-1.4) of the flea community, respectively. These last two species represented respectively 60.8% and 36.6% of the flea community on the bank vole and the wood mouse. Originated from Asia, chipmunks did not import any flea species to Sénart, probably because they were used as pets before their release in the wild. Abundance in C. s. sciurorum increased with adult chipmunk density and with juvenile density in summer. On adult chipmunks C. s. sciurorum tented to decrease with increasing abundance of red squirrels (Sciurus vulgaris]. Moreover, the two other flea species mainly infected young chipmunks during the fall, and their number was not related to chipmunk density. However, the distribution of species within the flea community became more balanced with increase juvenile chipmunk density. Overall, these results indicate that the close phyletic relationship between chipmunks and red squirrels contributed in the acquisition and the spread of fleas by chipmunks. Primary and secondary hosts densities, their habitat use, and more specifically burrowing activities and tree canopy use, also played a role in the spread of fleas on chipmunks.

A molecular survey of Rickettsia felis in fleas from cats and dogs in Sicily (Southern Italy.

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Elisabetta Giudice

Full Text Available Rickettsia felis, the agent of flea-borne spotted fever, has a cosmopolitan distribution. Its pathogenic role in humans has been demonstrated through molecular and serologic tests in several cases. The cat flea (Ctenocephalides felis is considered the main reservoir and the biological vector. The aim of this study was to assess the presence and occurrence of R. felis in fleas collected from dogs and cats in various sites of Palermo (Sicily. Between August and October 2012, 134 fleas were collected from 42 animals: 37 fleas from 13 dogs and 97 fleas from 29 cats. Two species of fleas were identified: 132 Ctenocephalides felis (98.51% collected on all animals and only two C. canis (1.49% on one dog. Out of 132 C. felis, 34 (25.76%, 12 from dogs (32.43% and 22 (22.68% from cats, were positive for R. felis DNA by a polymerase chain reaction (PCR, confirmed by sequencing. The only two C. canis fleas were negative. About half of examined animals (47.62%, 20/42 were infested with at least one infected flea; in particular 46.15% of dogs (6/13 and 48.28% of cats (14/29. It seems that in the Palermo district there is a peri-domestic cycle, with a relatively high prevalence of R. felis infection in the cat flea, an insect widely diffused in home environments and which can frequently bite humans. The results also suggest that R. felis should be considered in the human differential diagnosis of any spotted-like fever or febrile illness without a clear source of infection in Sicily, especially if the patient is known to have been exposed to flea bites.

Potential role for dog fleas in the cycle of Leishmania spp.

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Ferreira, Marilia Gabriele Prado Albuquerque; Fattori, Karina Reinaldo; Souza, Fausto; Lima, Valéria Marçal Felix

2009-10-28

Several species of Leishmania spp. cause diseases in humans that range from self-healing cutaneous lesions to fatal visceral leishmaniosis. It has been observed that besides being transmitted by sand flies, Leishmania spp. may also be transmitted by arthropods such as ticks and fleas. To investigate the possible role of dog fleas in the transmission of Leishmania spp., Ctenocefalides felis were removed from 22 dogs which were positive according to ELISA and rK-39 tests. A C. felis sample from each of the 22 dogs was used to infect a hamster. The 22 hamsters were euthanized 4 months after infection with the fleas and the blood was subjected to ELISA to detect antibody anti-Leishmania spp., and the spleen samples were submitted to PCR for detection of Leishmania spp. DNA. PCR and ELISA were both positive in 18.1% (4/22), with PCR alone being positive in 45% (10/22) and ELISA alone in only 9% (2/22). These results suggest the participation of dog fleas in the Leishmania spp. cycle. Confirmation that C. felis indeed transmit leishmaniosis to dogs requires new strategies against leishmaniosis to be enforced by public health authorities and which focus on better ways to keep dogs free of fleas.

Effects of temperature on the transmission of Yersinia Pestis by the flea, Xenopsylla Cheopis, in the late phase period.

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Schotthoefer, Anna M; Bearden, Scott W; Holmes, Jennifer L; Vetter, Sara M; Montenieri, John A; Williams, Shanna K; Graham, Christine B; Woods, Michael E; Eisen, Rebecca J; Gage, Kenneth L

2011-09-29

Traditionally, efficient flea-borne transmission of Yersinia pestis, the causative agent of plague, was thought to be dependent on a process referred to as blockage in which biofilm-mediated growth of the bacteria physically blocks the flea gut, leading to the regurgitation of contaminated blood into the host. This process was previously shown to be temperature-regulated, with blockage failing at temperatures approaching 30°C; however, the abilities of fleas to transmit infections at different temperatures had not been adequately assessed. We infected colony-reared fleas of Xenopsylla cheopis with a wild type strain of Y. pestis and maintained them at 10, 23, 27, or 30°C. Naïve mice were exposed to groups of infected fleas beginning on day 7 post-infection (p.i.), and every 3-4 days thereafter until day 14 p.i. for fleas held at 10°C, or 28 days p.i. for fleas held at 23-30°C. Transmission was confirmed using Y. pestis-specific antigen or antibody detection assays on mouse tissues. Although no statistically significant differences in per flea transmission efficiencies were detected between 23 and 30°C, efficiencies were highest for fleas maintained at 23°C and they began to decline at 27 and 30°C by day 21 p.i. These declines coincided with declining median bacterial loads in fleas at 27 and 30°C. Survival and feeding rates of fleas also varied by temperature to suggest fleas at 27 and 30°C would be less likely to sustain transmission than fleas maintained at 23°C. Fleas held at 10°C transmitted Y. pestis infections, although flea survival was significantly reduced compared to that of uninfected fleas at this temperature. Median bacterial loads were significantly higher at 10°C than at the other temperatures. Our results suggest that temperature does not significantly effect the per flea efficiency of Y. pestis transmission by X. cheopis, but that temperature is likely to influence the dynamics of Y. pestis flea-borne transmission, perhaps by affecting

Case report: pulicosis por Ctenocephalides felis felis en ovinos y caprinos en la sabana de Bogotá, Colombia

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Efraín Benavides Ortiz

2010-06-01

Full Text Available In Colombia the rearing of hair sheep and goats are expanding in various regions for being an alternative for meat and milk production at competitive prices due to their adaptability and easiness to digest rough fodder. Among the ectoparasites that affect small ruminants traditionally are recognized the lice and the sheep keds Melophagus ovinus (Díptera: Hippoboscidae, however fleas are not included. Here the occurrence of the common cat flea Ctenocephalides felis felis (Díptera: Siphonaptera affecting sheep and goats in a farm at the Sabana de Bogotá are described an so there was performed an epidemiological and parasitological evaluation. The barn maintained animals in rotational grazing at an approximated stocking rate of 25 head/ha, receiving additional supplements of hay and silage. The presence of the flea was confirmed in sheep and goats, young and adult, as well as in dogs. Diverse degrees of anemia were evidenced but the association between flea infestation and anemia, or the presence of other anemia producing agents could not be studied. In the farm synthetic parasiticides are not used, extracts of Ruda (Ruta graveolens are administered to mitigate parasitosis, without major efficacy. Sheep and goat breeders in the tropics should consider flea infestation as an agent causing adverse animal welfare situations in their farms. Control should start from the knowledge of the life cycle of the flea, trying to interrupt it.

A review of plague persistence with special emphasis on fleas

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Wimsatt, Jeffrey; Biggins, Dean E.

2009-01-01

Sylvatic plague is highly prevalent during infrequent epizootics that ravage the landscape of western North America. During these periods, plague dissemination is very efficient. Epizootics end when rodent and flea populations are decimated and vectored transmission declines. A second phase (enzootic plague) ensues when plague is difficult to detect from fleas, hosts or the environment, and presents less of a threat to public health.

Evidence of an aggregation pheromone in the flea beetle,Phyllotreta Cruciferae (Goeze) (Coleoptera: Chrysomelidae).

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Peng, C; Weiss, M J

1992-06-01

Laboratory olfactometer bioassays and field trapping experiments showed that the flea beetle,Phyllotreta cruciferae (Goeze), was highly attracted by oilseed rape(Brassica napus L.) when flea beetles were on the plant. This attraction was mediated by a flea beetle-produced aggregation pheromone based upon: (1) Oilseed rape damaged mechanically, or byP. cruciferae, or by diamondback moth,Plutella xylostella (L.), did not attractP. cruciferae. (2) Contact with the plants or feeding was required for the production of aggregation pheromone because oilseed rape alone was not attractive when separated from flea beetles by a screen. (3) Equal numbers of males and females were attracted.

The Biology and Ecology of Cat Fleas and Advancements in Their Pest Management: A Review

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Michael K. Rust

2017-10-01

Full Text Available The cat flea Ctenocephalides felis felis (Bouché is the most important ectoparasite of domestic cats and dogs worldwide. It has been two decades since the last comprehensive review concerning the biology and ecology of C. f. felis and its management. Since then there have been major advances in our understanding of the diseases associated with C. f. felis and their implications for humans and their pets. Two rickettsial diseases, flea-borne spotted fever and murine typhus, have been identified in domestic animal populations and cat fleas. Cat fleas are the primary vector of Bartonella henselae (cat scratch fever with the spread of the bacteria when flea feces are scratched in to bites or wounds. Flea allergic dermatitis (FAD common in dogs and cats has been successfully treated and tapeworm infestations prevented with a number of new products being used to control fleas. There has been a continuous development of new products with novel chemistries that have focused on increased convenience and the control of fleas and other arthropod ectoparasites. The possibility of feral animals serving as potential reservoirs for flea infestations has taken on additional importance because of the lack of effective environmental controls in recent years. Physiological insecticide resistance in C. f. felis continues to be of concern, especially because pyrethroid resistance now appears to be more widespread. In spite of their broad use since 1994, there is little evidence that resistance has developed to many of the on-animal or oral treatments such as fipronil, imidacloprid or lufenuron. Reports of the perceived lack of performance of some of the new on-animal therapies have been attributed to compliance issues and their misuse. Consequentially, there is a continuing need for consumer awareness of products registered for cats and dogs and their safety.

Feeding Behavior Modulates Biofilm-Mediated Transmission of Yersinia pestis by the Cat Flea, Ctenocephalides felis.

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David M Bland

2016-02-01

Full Text Available The cat flea, Ctenocephalides felis, is prevalent worldwide, will parasitize animal reservoirs of plague, and is associated with human habitations in known plague foci. Despite its pervasiveness, limited information is available about the cat flea's competence as a vector for Yersinia pestis. It is generally considered to be a poor vector, based on studies examining early-phase transmission during the first week after infection, but transmission potential by the biofilm-dependent proventricular-blocking mechanism has never been systematically evaluated. In this study, we assessed the vector competence of cat fleas by both mechanisms. Because the feeding behavior of cat fleas differs markedly from important rat flea vectors, we also examined the influence of feeding behavior on transmission dynamics.Groups of cat fleas were infected with Y. pestis and subsequently provided access to sterile blood meals twice-weekly, 5 times per week, or daily for 4 weeks and monitored for infection, the development of proventricular biofilm and blockage, mortality, and the ability to transmit. In cat fleas allowed prolonged, daily access to blood meals, mimicking their natural feeding behavior, Y. pestis did not efficiently colonize the digestive tract and could only be transmitted during the first week after infection. In contrast, cat fleas that were fed intermittently, mimicking the feeding behavior of the efficient vector Xenopsylla cheopis, could become blocked and regularly transmitted Y. pestis for 3-4 weeks by the biofilm-mediated mechanism, but early-phase transmission was not detected.The normal feeding behavior of C. felis, more than an intrinsic resistance to infection or blockage by Y. pestis, limits its vector competence. Rapid turnover of midgut contents results in bacterial clearance and disruption of biofilm accumulation in the proventriculus. Anatomical features of the cat flea foregut may also restrict transmission by both early-phase and

Feeding Behavior Modulates Biofilm-Mediated Transmission of Yersinia pestis by the Cat Flea, Ctenocephalides felis.

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Bland, David M; Hinnebusch, B Joseph

2016-02-01

The cat flea, Ctenocephalides felis, is prevalent worldwide, will parasitize animal reservoirs of plague, and is associated with human habitations in known plague foci. Despite its pervasiveness, limited information is available about the cat flea's competence as a vector for Yersinia pestis. It is generally considered to be a poor vector, based on studies examining early-phase transmission during the first week after infection, but transmission potential by the biofilm-dependent proventricular-blocking mechanism has never been systematically evaluated. In this study, we assessed the vector competence of cat fleas by both mechanisms. Because the feeding behavior of cat fleas differs markedly from important rat flea vectors, we also examined the influence of feeding behavior on transmission dynamics. Groups of cat fleas were infected with Y. pestis and subsequently provided access to sterile blood meals twice-weekly, 5 times per week, or daily for 4 weeks and monitored for infection, the development of proventricular biofilm and blockage, mortality, and the ability to transmit. In cat fleas allowed prolonged, daily access to blood meals, mimicking their natural feeding behavior, Y. pestis did not efficiently colonize the digestive tract and could only be transmitted during the first week after infection. In contrast, cat fleas that were fed intermittently, mimicking the feeding behavior of the efficient vector Xenopsylla cheopis, could become blocked and regularly transmitted Y. pestis for 3-4 weeks by the biofilm-mediated mechanism, but early-phase transmission was not detected. The normal feeding behavior of C. felis, more than an intrinsic resistance to infection or blockage by Y. pestis, limits its vector competence. Rapid turnover of midgut contents results in bacterial clearance and disruption of biofilm accumulation in the proventriculus. Anatomical features of the cat flea foregut may also restrict transmission by both early-phase and proventricular biofilm

The Biology and Ecology of Cat Fleas and Advancements in Their Pest Management: A Review

Science.gov (United States)

2017-01-01

The cat flea Ctenocephalides felis felis (Bouché) is the most important ectoparasite of domestic cats and dogs worldwide. It has been two decades since the last comprehensive review concerning the biology and ecology of C. f. felis and its management. Since then there have been major advances in our understanding of the diseases associated with C. f. felis and their implications for humans and their pets. Two rickettsial diseases, flea-borne spotted fever and murine typhus, have been identified in domestic animal populations and cat fleas. Cat fleas are the primary vector of Bartonella henselae (cat scratch fever) with the spread of the bacteria when flea feces are scratched in to bites or wounds. Flea allergic dermatitis (FAD) common in dogs and cats has been successfully treated and tapeworm infestations prevented with a number of new products being used to control fleas. There has been a continuous development of new products with novel chemistries that have focused on increased convenience and the control of fleas and other arthropod ectoparasites. The possibility of feral animals serving as potential reservoirs for flea infestations has taken on additional importance because of the lack of effective environmental controls in recent years. Physiological insecticide resistance in C. f. felis continues to be of concern, especially because pyrethroid resistance now appears to be more widespread. In spite of their broad use since 1994, there is little evidence that resistance has developed to many of the on-animal or oral treatments such as fipronil, imidacloprid or lufenuron. Reports of the perceived lack of performance of some of the new on-animal therapies have been attributed to compliance issues and their misuse. Consequentially, there is a continuing need for consumer awareness of products registered for cats and dogs and their safety. PMID:29077073

Spatiotemporal variations of the incidence of the fleas (Siphonaptera ...

African Journals Online (AJOL)

SARAH

2014-08-31

Aug 31, 2014 ... Therefore, awareness of the authorities on the zoonotic risk of small ... Human Health in Benin must sensitize the populations at high risk of the rodent transmitted diseases. ..... Preventive. Veterinary Medicine 60: 227-235.

Myxomatosis: some observations on breeding the European rabbit flea Spilopsyllus cuniculi (Dale) in an animal house

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Sobey, W. R.; Menzies, W.; Conolly, Dorothy

1974-01-01

Rabbit fleas for use in Myxomatosis investigations have been successfully bred on rabbits in an animal house. The timing of emergence appeared to be governed by a biological timing control interacting with different forms of disturbance. Yield was found to be related to litter size, the time the doe and her kittens were removed from the nest, the number of fleas put onto a doe before littering and the mean ambient temperature to which the doe was exposed in the week pre-partum. The survival rate of fleas in storage was affected by temperature, the degree of crowding, moisture content of the containers, whether fleas were fed or unfed and the source of fleas in terms of emergence times. PMID:4526409

Evidence of Yersinia pestis DNA from fleas in an endemic plague area of Zambia

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Hang'ombe Bernard M

2012-01-01

Full Text Available Abstract Background Yersinia pestis is a bacterium that causes plague which infects a variety of mammals throughout the world. The disease is usually transmitted among wild rodents through a flea vector. The sources and routes of transmission of plague are poorly researched in Africa, yet remains a concern in several sub-Saharan countries. In Zambia, the disease has been reported on annual basis with up to 20 cases per year, without investigating animal reservoirs or vectors that may be responsible in the maintenance and propagation of the bacterium. In this study, we undertook plague surveillance by using PCR amplification of the plasminogen activator gene in fleas. Findings Xenopsylla species of fleas were collected from 83 rodents trapped in a plague endemic area of Zambia. Of these rodents 5 had fleas positive (6.02% for Y. pestis plasminogen activator gene. All the Y. pestis positive rodents were gerbils. Conclusions We conclude that fleas may be responsible in the transmission of Y. pestis and that PCR may provide means of plague surveillance in the endemic areas of Zambia.

Real-time PCR of the mammalian hydroxymethylbilane synthase (HMBS gene for analysis of flea (Ctenocephalides felis feeding patterns on dogs

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Wang Chengming

2012-01-01

Full Text Available Abstract Background Precise data on quantitative kinetics of blood feeding of fleas, particularly immediately after contact with the host, are essential for understanding dynamics of flea-borne disease transmission and for evaluating flea control strategies. Standard methods used are inadequate for studies that simulate early events after real-life flea access to the host. Methods Here, we developed a novel quantitative polymerase chain reaction targeting mammalian DNA within fleas to quantify blood consumption with high sensitivity and specificity. We used primers and fluorescent probes that amplify the hydroxymethylbilane synthase (HMBS gene, an evolutionary divergent gene that is unlikely to be detected in insects by mammalian-specific primers and probes. To validate this assay, fleas were placed on dogs, allowed to distribute in the hair, and removed at specific time points with single-use combs. Fleas were then immediately homogenized by vigorous shaking with ceramic beads in guanidinium-based DNA preservation buffer for DNA extraction. Results The specificity of this assay was ascertained by amplification of canine, feline and equine blood with differential product melting temperatures (Tm, and lack of amplification of bovine and porcine blood and of adult fleas reared from larvae fed with bovine blood. Sensitivity of the assay was established by limiting dilution and detection of single copies of HMBS DNA equivalent to 0.043 nL blood. Application of the assay indicated that after 15 minutes on a dog, male and female fleas had ingested low, but similar amounts of approximately 1.1. nL blood. Saturation uptake of 118 and 100 nL blood per flea was found at 30 and 60 min on the dog, respectively. Conclusions The HMBS PCR method developed here offers the advantages of both exquisite sensitivity and specificity that make it superior to other approaches for quantification of blood ingested by fleas. The capability to detect minute quantities of

Feeding Behavior Modulates Biofilm-Mediated Transmission of Yersinia pestis by the Cat Flea, Ctenocephalides felis

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Bland, David M.; Hinnebusch, B. Joseph

2016-01-01

Background The cat flea, Ctenocephalides felis, is prevalent worldwide, will parasitize animal reservoirs of plague, and is associated with human habitations in known plague foci. Despite its pervasiveness, limited information is available about the cat flea’s competence as a vector for Yersinia pestis. It is generally considered to be a poor vector, based on studies examining early-phase transmission during the first week after infection, but transmission potential by the biofilm-dependent proventricular-blocking mechanism has never been systematically evaluated. In this study, we assessed the vector competence of cat fleas by both mechanisms. Because the feeding behavior of cat fleas differs markedly from important rat flea vectors, we also examined the influence of feeding behavior on transmission dynamics. Methodology/Principal Findings Groups of cat fleas were infected with Y. pestis and subsequently provided access to sterile blood meals twice-weekly, 5 times per week, or daily for 4 weeks and monitored for infection, the development of proventricular biofilm and blockage, mortality, and the ability to transmit. In cat fleas allowed prolonged, daily access to blood meals, mimicking their natural feeding behavior, Y. pestis did not efficiently colonize the digestive tract and could only be transmitted during the first week after infection. In contrast, cat fleas that were fed intermittently, mimicking the feeding behavior of the efficient vector Xenopsylla cheopis, could become blocked and regularly transmitted Y. pestis for 3–4 weeks by the biofilm-mediated mechanism, but early-phase transmission was not detected. Conclusions The normal feeding behavior of C. felis, more than an intrinsic resistance to infection or blockage by Y. pestis, limits its vector competence. Rapid turnover of midgut contents results in bacterial clearance and disruption of biofilm accumulation in the proventriculus. Anatomical features of the cat flea foregut may also restrict

Droughts may increase susceptibility of prairie dogs to fleas: Incongruity with hypothesized mechanisms of plague cycles in rodents

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Eads, David A.; Biggins, Dean E.; Long, Dustin H.; Gage, Kenneth L.; Antolin, Michael F.

2016-01-01

Plague is a reemerging, rodent-associated zoonosis caused by the flea-borne bacterium Yersinia pestis. As a vector-borne disease, rates of plague transmission may increase when fleas are abundant. Fleas are highly susceptible to desiccation under hot-dry conditions; we posited that their densities decline during droughts. We evaluated this hypothesis with black-tailed prairie dogs (Cynomys ludovicianus) in New Mexico, June–August 2010–2012. Precipitation was relatively plentiful during 2010 and 2012 but scarce during 2011, the driest spring–summer on record for the northeastern grasslands of New Mexico. Unexpectedly, fleas were 200% more abundant in 2011 than in 2010 and 2012. Prairie dogs were in 27% better condition during 2010 and 2012, and they devoted 287% more time to grooming in 2012 than in 2011. During 2012, prairie dogs provided with supplemental food and water were in 23% better condition and carried 40% fewer fleas. Collectively, these results suggest that during dry years, prairie dogs are limited by food and water, and they exhibit weakened defenses against fleas. Long-term data are needed to evaluate the generality of whether droughts increase flea densities and how changes in flea abundance during sequences of dry and wet years might affect plague cycles in mammalian hosts.

Retracing the evolutionary path that led to flea-borne transmission of Yersinia pestis.

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Sun, Yi-Cheng; Jarrett, Clayton O; Bosio, Christopher F; Hinnebusch, B Joseph

2014-05-14

Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced cyclic-di-GMP-mediated bacterial biofilm formation in the flea foregut, which greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation. Copyright © 2014 Elsevier Inc. All rights reserved.

Feeding Behavior Modulates Biofilm-Mediated Transmission of Yersinia pestis by the Cat Flea, Ctenocephalides felis

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Bland, David M.; Hinnebusch, B. Joseph

2016-01-01

Background The cat flea, Ctenocephalides felis, is prevalent worldwide, will parasitize animal reservoirs of plague, and is associated with human habitations in known plague foci. Despite its pervasiveness, limited information is available about the cat flea?s competence as a vector for Yersinia pestis. It is generally considered to be a poor vector, based on studies examining early-phase transmission during the first week after infection, but transmission potential by the biofilm-dependent p...

Market Hydraulics and Subjectivities in the "Wild": Circulations of the Flea Market

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Niklas Hansson

2015-03-01

Full Text Available Since consumer researchers started paying attention to flea markets they represent common consumer and market research objects. Arguably, in the "natural laboratory" of the flea market, researchers can observe and theorize market and consumer processes "in the wild", as forms of direct marketing and consumption. We build on existing flea market research through adopting a circulatory approach, inspired by actor-network theory (ANT. Rather than presenting a theory of (flea markets, ANT is useful for studying markets from the perspective of grounded market-making processes. Consumption is understood as the interplay of consumers, marketers, retailers, and a wide array of artifacts and market mediators like products, economic theories and ideas, packaging, market space (in the physical sense and furniture, etc. Our results point out that not only does such an approach enable analysis of features commonly studied within consumer research such as calculative action and social interaction, but also issues more rarely in focus in such research, such as cognitive patterns of consumer curiosity, emotions, senses, and affect. Furthermore, even though flea markets foremost are places of commerce and exchange of second hand goods, there is a large variety of other forms of flows or circulations going on "backstage" that enable the surface phenomena of second hand consumption to come into being. Many of these circulations, we argue, are material rather than immaterial Vendor and buyer subjectivities are thus understood as outcomes of circulatory dynamism that involves a range of material and immaterial flows.

Molecular Detection of Rickettsia felis in Humans, Cats, and Cat Fleas in Bangladesh, 2013-2014.

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Ahmed, Rajib; Paul, Shyamal Kumar; Hossain, Muhammad Akram; Ahmed, Salma; Mahmud, Muhammad Chand; Nasreen, Syeda Anjuman; Ferdouse, Faria; Sharmi, Rumana Hasan; Ahamed, Farid; Ghosh, Souvik; Urushibara, Noriko; Aung, Meiji Soe; Kobayashi, Nobumichi

2016-05-01

High prevalence of Rickettsia felis in patients with fever of unknown origin was revealed in the north-central Bangladesh from 2012 to 2013. Subsequently, in this study, prevalence of R. felis in cats and cat fleas (Ctenocephalides felis), together with febrile patients, was studied by PCR detection of 17 kDa antigen gene and DNA sequencing. R. felis was detected in 28% (28/100) and 21% (14/68) of cat blood and cat flea samples, respectively, whereas 42% (21/50) of patients were positive for R. felis. R. felis-positive cat fleas were detected at significantly higher rate on R. felis-positive cats. The results suggested a potential role of cats and cat fleas for transmission of R. felis to humans in Bangladesh.

Comparative Ability of Oropsylla montana and Xenopsylla cheopis Fleas to Transmit Yersinia pestis by Two Different Mechanisms.

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B Joseph Hinnebusch

2017-01-01

Full Text Available Transmission of Yersinia pestis by flea bite can occur by two mechanisms. After taking a blood meal from a bacteremic mammal, fleas have the potential to transmit the very next time they feed. This early-phase transmission resembles mechanical transmission in some respects, but the mechanism is unknown. Thereafter, transmission occurs after Yersinia pestis forms a biofilm in the proventricular valve in the flea foregut. The biofilm can impede and sometimes completely block the ingestion of blood, resulting in regurgitative transmission of bacteria into the bite site. In this study, we compared the relative efficiency of the two modes of transmission for Xenopsylla cheopis, a flea known to become completely blocked at a high rate, and Oropsylla montana, a flea that has been considered to rarely develop proventricular blockage.Fleas that took an infectious blood meal containing Y. pestis were maintained and monitored for four weeks for infection and proventricular blockage. The number of Y. pestis transmitted by groups of fleas by the two modes of transmission was also determined. O. montana readily developed complete proventricular blockage, and large numbers of Y. pestis were transmitted by that mechanism both by it and by X. cheopis, a flea known to block at a high rate. In contrast, few bacteria were transmitted in the early phase by either species.A model system incorporating standardized experimental conditions and viability controls was developed to more reliably compare the infection, proventricular blockage and transmission dynamics of different flea vectors, and was used to resolve a long-standing uncertainty concerning the vector competence of O. montana. Both X. cheopis and O. montana are fully capable of transmitting Y. pestis by the proventricular biofilm-dependent mechanism.

Occurrence of Dipylidium caninum in fleas from client-owned cats and dogs in Europe using a new PCR detection assay.

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Beugnet, Frédéric; Labuschagne, Michel; Fourie, Josephus; Jacques, Guillot; Farkas, Robert; Cozma, Vasile; Halos, Lénaïg; Hellmann, Klaus; Knaus, Martin; Rehbein, Steffen

2014-09-15

Ctenocephalides fleas are not only the most prevalent ectoparasites of dogs and cats but also the intermediate host of the cestode Dipylidium caninum. Due to the poor sensitivity of coproscopy to diagnose cat and dog infestation by Dipylidium, few epidemiological data are available on its prevalence among pet populations. A new PCR method was developed to specifically identify D. caninum rDNA inside single fleas. The PCR test was then applied to 5529 fleas of Ctenocephalides genus, 2701 Ctenocephalides felis fleas (1969 collected on 435 cats and 732 on 178 dogs) and 2828 Ctenocephalides canis fleas collected from 396 dogs. Precisely, 4.37% of cats were infested by a flea population infected with D. caninum. Out of the 1969 C. felis from cats, 2.23% were found to be infected with Dipylidium. From the 396 dogs infested with C. canis, 9.1%% were infested with the Dipylidium infected fleas, which is significantly higher than the observation made in cats (p=0.03). Moreover, 3.1% of the C. canis fleas were found to be infected with Dipylidium, which is not significantly different than in C. felis. Looking at the number of infected fleas in the positive samples (at least one PCR positive flea in a sample), the infestation rate in samples was varied from 3 to 100% with an average of 19.7% which is in favour of easy and regular Dipylidium reinfestations of both cats and dogs in households. For the first time, the spread of D. caninum between fleas and dogs and cats is confirmed throughout Europe. Copyright © 2014 Elsevier B.V. All rights reserved.

Dipylidium (Dog and Cat Flea Tapeworm) FAQs

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... the most common kind of tapeworm dogs and cats get? The most common tapeworm of dogs and cats in the United States is called Dipylidium caninum . ... infected with a tapeworm larvae. A dog or cat may swallow a flea while self-grooming. Once ...

Flea diversity as an element for persistence of plague bacteria in an East African plague focus.

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Rebecca J Eisen

Full Text Available Plague is a flea-borne rodent-associated zoonotic disease that is caused by Yersinia pestis and characterized by long quiescent periods punctuated by rapidly spreading epidemics and epizootics. How plague bacteria persist during inter-epizootic periods is poorly understood, yet is important for predicting when and where epizootics are likely to occur and for designing interventions aimed at local elimination of the pathogen. Existing hypotheses of how Y. pestis is maintained within plague foci typically center on host abundance or diversity, but little attention has been paid to the importance of flea diversity in enzootic maintenance. Our study compares host and flea abundance and diversity along an elevation gradient that spans from low elevation sites outside of a plague focus in the West Nile region of Uganda (~725-1160 m to higher elevation sites within the focus (~1380-1630 m. Based on a year of sampling, we showed that host abundance and diversity, as well as total flea abundance on hosts was similar between sites inside compared with outside the plague focus. By contrast, flea diversity was significantly higher inside the focus than outside. Our study highlights the importance of considering flea diversity in models of Y. pestis persistence.

Transmission efficiency of the plague pathogen (Y. pestis) by the flea, Xenopsylla skrjabini, to mice and great gerbils.

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Zhang, Yujiang; Dai, Xiang; Wang, Qiguo; Chen, Hongjian; Meng, Weiwei; Wu, Kemei; Luo, Tao; Wang, Xinhui; Rehemu, Azhati; Guo, Rong; Yu, Xiaotao; Yang, Ruifu; Cao, Hanli; Song, Yajun

2015-05-01

Plague, a zoonotic disease caused by Yersinia pestis, is characterized by its ability to persist in the plague natural foci. Junggar Basin plague focus was recently identified in China, with Rhombomys opimus (great gerbils) and Xenopsylla skrjabini as the main reservoir and vector for plague. No transmission efficiency data of X. skrjabini for Y. pestis is available till now. In this study, we estimated the median infectious dose (ID50) and the blockage rates of X. skrjabini with Y. pestis, by using artificial feeders. We then evaluated the flea transmission ability of Y. pestis to the mice and great gerbils via artificial bloodmeal feeding. Finally, we investigated the transmission of Y. pestis to mice with fleas fed by infected great gerbils. ID50 of Y. pestis to X. skrjabini was estimated as 2.04 × 10(5) CFU (95% CI, 1.45 × 10(5) - 3.18 × 10(5) CFU), around 40 times higher than that of X. cheopis. Although fleas fed by higher bacteremia bloodmeal had higher infection rates for Y. pestis, they lived significantly shorter than their counterparts. X. skrjabini could get fully blocked as early as day 3 post of infection (7.1%, 3/42 fleas), and the overall blockage rate of X. cheopis was estimated as 14.9% (82/550 fleas) during the 14 days of investigation. For the fleas infected by artificial feeders, they seemed to transmit plague more efficiently to great gerbils than mice. Our single flea transmission experiments also revealed that, the transmission capacity of naturally infected fleas (fed by infected great gerbils) was significantly higher than that of artificially infected ones (fed by artificial feeders). Our results indicated that ID50 of Y. pestis to X. skrjabini was higher than other fleas like X. cheopis, and its transmission efficiency to mice might be lower than other flea vectors in the artificial feeding modes. We also found different transmission potentials in the artificially infected fleas and the naturally infected ones. Further studies are

Preventive efficacy of NexGard Spectra® against Dipylidium caninum infection in dogs using a natural flea (Ctenocephalides felis infestation model

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Beugnet Frédéric

2017-01-01

Full Text Available The efficacy of a monthly oral endectocide product, NexGard Spectra® (Merial, a combination of afoxolaner and milbemycin oxime, was evaluated in a flea (Ctenocephalides felis challenge model for the prevention of Dipylidium caninum tapeworm infection in dogs. The efficacy of treatment with NexGard Spectra® was assessed in 10 dogs following weekly flea infestation with metacestode naturally infected fleas and compared with that in 10 untreated control dogs. The 100 fleas deposited weekly on each dog were not removed until Day 35, allowing enough time for their ingestion. The microscopical analysis of 30 fleas from the flea batches before each weekly challenge demonstrated that 10–33% of the fleas were infected by D. caninum cysticercoid larvae. The arithmetic mean flea count recorded was 47.7 for the 10 untreated dogs and 0 for the 10 treated dogs at Day 35. Based on the daily collection of expelled D. caninum proglottids by dogs during the 70 days of the study, 70% (7/10 of the control dogs and 0% (0/10 of the treated dogs were infected with D. caninum (p < 0.0031. Through its efficacy against fleas, NexGard Spectra® treatment provided indirect prevention of D. caninum infestation. No treatment-related adverse events were observed in dogs during this study.

Control of immature stages of the flea Ctenocephalides felis(Bouché in carpets exposed to cats treated with imidacloprid

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L.J. Fourie

2000-07-01

Full Text Available Fleas cause allergic dermatitis in cats and dogs and therefore warrant control. It has been demonstrated previously that there is marked inhibition of the development of the immature stages of the cat flea Ctenocephalides felis on fleece blankets exposed to cats treated with imidacloprid. This study reports on the efficacy of imidacloprid in suppressing adult flea emergence in carpet exposed to treated cats. Circular discs of carpet pre-seeded with flea eggs and larvae were exposed to 6 untreated control and 6 topically treated (imidacloprid 10 % m/v cats 1 to 2 days after treatment and subsequently fortnightly for 6 weeks. Exposure times on alternate days were either 1 or 6 hours. Adult flea yield from carpets was determined 35 days after exposure. Differences between flea yield on control carpets and those exposed for 1 hour were significant only for days +1 and +14. For the 6-hour exposure, differences were significant at all times except on Day +43. The ability of imidacloprid to suppress the yield of adult fleas on carpets (6-hour exposure steadily declined from 82 % (Day +2 to 12 %(Day +43. For the 1-hour exposure it varied inconsistently between 0 and 83 % over the 6-week study period.

Contribution of land use to rodent flea load distribution in the plague endemic area of Lushoto District, Tanzania.

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Hieronimo, Proches; Kihupi, Nganga I; Kimaro, Didas N; Gulinck, Hubert; Mulungu, Loth S; Msanya, Balthazar M; Leirs, Herwig; Deckers, Jozef A

2014-07-01

Fleas associated with different rodent species are considered as the major vectors of bubonic plague, which is still rampant in different parts of the world. The objective of this study was to investigate the contribution of land use to rodent flea load distribution at fine scale in the plague endemic area of north-eastern Tanzania. Data was collected in three case areas namely, Shume, Lukozi and Mwangoi, differing in plague incidence levels. Data collection was carried out during both wet and dry seasons of 2012. Analysis of Variance and Boosted Regression Tree (BRT) statistical methods were used to clarify the relationships between fleas and specific land use characteristics. There was a significant variation (P ≤ 0.05) of flea indices in different land use types. Fallow and natural forest had higher flea indices whereas plantation forest mono-crop and mixed annual crops had the lowest flea indices among the aggregated land use types. The influence of individual land use types on flea indices was variable with fallow having a positive effect and land tillage showing a negative effect. The results also demonstrated a seasonal effect, part of which can be attributed to different land use practices such as application of pesticides, or the presence of grass strips around fields. These findings suggest that land use factors have a major influence on rodent flea abundance which can be taken as a proxy for plague infection risk. The results further point to the need for a comprehensive package that includes land tillage and crop type considerations on one hand and the associated human activities on the other, in planning and implementation of plague control interventions.

Rickettsial Infections among Ctenocephalides felis and Host Animals during a Flea-Borne Rickettsioses Outbreak in Orange County, California

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Fogarty, Carrie; Krueger, Laura; Macaluso, Kevin R.; Odhiambo, Antony; Nguyen, Kiet; Farris, Christina M.; Luce-Fedrow, Alison; Bennett, Stephen; Jiang, Ju; Sun, Sokanary; Cummings, Robert F.; Richards, Allen L.

2016-01-01

Due to a resurgence of flea-borne rickettsioses in Orange County, California, we investigated the etiologies of rickettsial infections of Ctenocephalides felis, the predominant fleas species obtained from opossums (Didelphis virginiana) and domestic cats (Felis catus), collected from case exposure sites and other areas in Orange County. In addition, we assessed the prevalence of IgG antibodies against spotted fever group (SFGR) and typhus group (TGR) rickettsiae in opossum sera. Of the 597 flea specimens collected from opossums and cats, 37.2% tested positive for Rickettsia. PCR and sequencing of rickettsial genes obtained from C. felis flea DNA preparations revealed the presence of R. typhi (1.3%), R. felis (28.0%) and R. felis-like organisms (7.5%). Sera from opossums contained TGR-specific (40.84%), but not SFGR-specific antibodies. The detection of R. felis and R. typhi in the C. felis fleas in Orange County highlights the potential risk for human infection with either of these pathogens, and underscores the need for further investigations incorporating specimens from humans, animal hosts, and invertebrate vectors in endemic areas. Such studies will be essential for establishing a link in the ongoing flea-borne rickettsioses outbreaks. PMID:27537367

Phylogenetic Analysis of Entomoparasitic Nematodes, Potential Control Agents of Flea Populations in Natural Foci of Plague

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Koshel, E. I.; Aleshin, V. V.; Eroshenko, G. A.; Kutyrev, V. V.

2014-01-01

Entomoparasitic nematodes are natural control agents for many insect pests, including fleas that transmit Yersinia pestis, a causative agent of plague, in the natural foci of this extremely dangerous zoonosis. We examined the flea samples from the Volga-Ural natural focus of plague for their infestation with nematodes. Among the six flea species feeding on different rodent hosts (Citellus pygmaeus, Microtus socialis, and Allactaga major), the rate of infestation varied from 0 to 21%. The propagation rate of parasitic nematodes in the haemocoel of infected fleas was very high; in some cases, we observed up to 1,000 juveniles per flea specimen. Our study of morphology, life cycle, and rDNA sequences of these parasites revealed that they belong to three distinct species differing in the host specificity. On SSU and LSU rRNA phylogenies, these species representing three genera (Rubzovinema, Psyllotylenchus, and Spilotylenchus), constitute a monophyletic group close to Allantonema and Parasitylenchus, the type genera of the families Allantonematidae and Parasitylenchidae (Nematoda: Tylenchida). We discuss the SSU-ITS1-5.8S-LSU rDNA phylogeny of the Tylenchida with a special emphasis on the suborder Hexatylina. PMID:24804197

Preventive efficacy of NexGard Spectra® against Dipylidium caninum infection in dogs using a natural flea (Ctenocephalides felis) infestation model.

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Beugnet, Frédéric; Meyer, Leon; Fourie, Josephus; Larsen, Diane

2017-01-01

The efficacy of a monthly oral endectocide product, NexGard Spectra ® (Merial), a combination of afoxolaner and milbemycin oxime, was evaluated in a flea (Ctenocephalides felis) challenge model for the prevention of Dipylidium caninum tapeworm infection in dogs. The efficacy of treatment with NexGard Spectra ® was assessed in 10 dogs following weekly flea infestation with metacestode naturally infected fleas and compared with that in 10 untreated control dogs. The 100 fleas deposited weekly on each dog were not removed until Day 35, allowing enough time for their ingestion. The microscopical analysis of 30 fleas from the flea batches before each weekly challenge demonstrated that 10-33% of the fleas were infected by D. caninum cysticercoid larvae. The arithmetic mean flea count recorded was 47.7 for the 10 untreated dogs and 0 for the 10 treated dogs at Day 35. Based on the daily collection of expelled D. caninum proglottids by dogs during the 70 days of the study, 70% (7/10) of the control dogs and 0% (0/10) of the treated dogs were infected with D. caninum (p caninum infestation. No treatment-related adverse events were observed in dogs during this study. © F. Beugnet et al., published by EDP Sciences, 2017.

Preventive efficacy of NexGard Spectra® against Dipylidium caninum infection in dogs using a natural flea (Ctenocephalides felis) infestation model

OpenAIRE

Beugnet Frédéric; Meyer Leon; Fourie Josephus; Larsen Diane

2017-01-01

The efficacy of a monthly oral endectocide product, NexGard Spectra? (Merial), a combination of afoxolaner and milbemycin oxime, was evaluated in a flea (Ctenocephalides felis) challenge model for the prevention of Dipylidium caninum tapeworm infection in dogs. The efficacy of treatment with NexGard Spectra? was assessed in 10 dogs following weekly flea infestation with metacestode naturally infected fleas and compared with that in 10 untreated control dogs. The 100 fleas deposited weekly on ...

Prophylactic treatment of flea-infested cats with an imidacloprid/flumethrin collar to forestall infection with Dipylidium caninum.

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Fourie, Josephus J; Crafford, Dionne; Horak, Ivan G; Stanneck, Dorothee

2012-07-27

The objective of the study was to determine the sustained effectiveness of 10% imidacloprid (w/w) and 4.5% flumethrin (w/w) incorporated in a slow-release matrix collar in preventing Dipylidium caninum infection in cats following repeated laboratory-infestations with fleas infected with metacestodes. Efficacy against infection with D. caninum was evaluated by infesting 16 cats with the flea Ctenocephalides felis felis infected with metacestodes of the tapeworm. Medicated collars were fitted to 8 of the cats and infestation of each cat with 200 fleas from a suitably infected batch commenced 7 days later and continued at weekly intervals until Day 28. Efficacy against fleas was evaluated 24 h after each infestation. Infection of the cats with D. caninum was verified by daily examination of the cats' faeces and immediate surroundings for proglottids from Day 21 to Day 60. Calculation of the prophylactic effectiveness of the collars in preventing infection of the cats with D. caninum was based on the difference in the geometric mean number of scoleces recovered from the gastrointestinal tracts of collared compared to untreated cats at necropsy on Day 61. Efficacy of the collars against infestation of the cats with fleas was 99.9% on Day 7 and 100% at each subsequent weekly assessment. Infection of the fleas with metacestodes was ≥40% in 7 to 13 day old fleas, but progressively decreased thereafter. At necropsy all the control cats were infected with D. caninum and harboured between 19 and 346 scoleces with a geometric mean of 58.3. A single treated cat was infected and harboured 2 scoleces. Effective prevention of infection with D. caninum, based on a comparison of the geometric mean numbers of scoleces recovered from control and treated cats, was 99.7%. The insecticidal components of the medicated collars are capable of rapidly eliminating newly-acquired infestations of fleas that are infected with the metacestodes of D. caninum, thus preventing infection with the

Prophylactic treatment of flea-infested cats with an imidacloprid/flumethrin collar to forestall infection with Dipylidium caninum

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Fourie Josephus J

2012-07-01

Full Text Available Abstract Background The objective of the study was to determine the sustained effectiveness of 10% imidacloprid (w/w and 4.5% flumethrin (w/w incorporated in a slow-release matrix collar in preventing Dipylidium caninum infection in cats following repeated laboratory-infestations with fleas infected with metacestodes. Methods Efficacy against infection with D. caninum was evaluated by infesting 16 cats with the flea Ctenocephalides felis felis infected with metacestodes of the tapeworm. Medicated collars were fitted to 8 of the cats and infestation of each cat with 200 fleas from a suitably infected batch commenced 7 days later and continued at weekly intervals until Day 28. Efficacy against fleas was evaluated 24 h after each infestation. Infection of the cats with D. caninum was verified by daily examination of the cats’ faeces and immediate surroundings for proglottids from Day 21 to Day 60. Calculation of the prophylactic effectiveness of the collars in preventing infection of the cats with D. caninum was based on the difference in the geometric mean number of scoleces recovered from the gastrointestinal tracts of collared compared to untreated cats at necropsy on Day 61. Results Efficacy of the collars against infestation of the cats with fleas was 99.9% on Day 7 and 100% at each subsequent weekly assessment. Infection of the fleas with metacestodes was ≥40% in 7 to 13 day old fleas, but progressively decreased thereafter. At necropsy all the control cats were infected with D. caninum and harboured between 19 and 346 scoleces with a geometric mean of 58.3. A single treated cat was infected and harboured 2 scoleces. Effective prevention of infection with D. caninum, based on a comparison of the geometric mean numbers of scoleces recovered from control and treated cats, was 99.7%. Conclusion The insecticidal components of the medicated collars are capable of rapidly eliminating newly-acquired infestations of fleas that are infected

Role of the Yersinia pestis yersiniabactin iron acquisition system in the incidence of flea-borne plague.

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Florent Sebbane

2010-12-01

Full Text Available Plague is a flea-borne zoonosis caused by the bacterium Yersinia pestis. Y. pestis mutants lacking the yersiniabactin (Ybt siderophore-based iron transport system are avirulent when inoculated intradermally but fully virulent when inoculated intravenously in mice. Presumably, Ybt is required to provide sufficient iron at the peripheral injection site, suggesting that Ybt would be an essential virulence factor for flea-borne plague. Here, using a flea-to-mouse transmission model, we show that a Y. pestis strain lacking the Ybt system causes fatal plague at low incidence when transmitted by fleas. Bacteriology and histology analyses revealed that a Ybt-negative strain caused only primary septicemic plague and atypical bubonic plague instead of the typical bubonic form of disease. The results provide new evidence that primary septicemic plague is a distinct clinical entity and suggest that unusual forms of plague may be caused by atypical Y. pestis strains.

Prophylactic treatment of flea-infested dogs with an imidacloprid / flumethrin collar (Seresto®, Bayer) to preempt infection with Dipylidium caninum.

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Fourie, Josephus J; Crafford, Dionne; Horak, Ivan G; Stanneck, Dorothee

2013-08-01

The objective of the study was to determine the sustained effectiveness of 10 % imidacloprid and 4.5 % flumethrin, incorporated in a slow-release matrix collar, in preventing Dipylidium caninum infection in dogs after repeated laboratory infestations with fleas infected with metacestodes of this tapeworm. Efficacy against infection with D. caninum was evaluated by infesting 16 dogs with cat fleas (Ctenocephalides felis) on study days 7, 14, 21, 28, 35 and 42, from batches suitably infected with D. caninum metacestodes. Prior to each post-treatment infestation the D. caninum infection rate for the fleas was determined by microscopically examining 100 fleas for D. caninum metacestodes. The D. caninum prevalence in the fleas used for infestations ranged from 23 % to 52 %. Medicated collars were fitted to 8 of the dogs on study day 0. The weight of the IVP collars varied between 35.48 g and 38.48 g (average 37.16 g), whilst animal weight varied between 12.20 kg and 17.98 kg (treated group, n = 8, average 14.79 kg). Seven days later infestation of each of the 16 dogs with 250 fleas commenced. Infestations continued at weekly intervals until Day 42 with efficacy against fleas evaluated 24 hours after each infestation. From Days 21 to 74, infection of the dogs with D. caninum was verified (daily examination of faeces and cages for the presence of expelled proglottids). Calculation of prophylactic effectiveness of the collars in preventing infection with D. caninum was based on the difference in geometric mean numbers of scoleces between groups at necropsy on Day 75. Effective prevention of infection with D. caninum was found to be 96.6 %. Efficacy of the collars against fleas was ≥ 99.9 % for the duration of the assessment period. Newly acquired infestations of fleas are rapidly eliminated by the insecticidal components of the medicated collars over a period of several months. In the event of fleas being infected with metacestodes, with D. caninum can be prevented in

Assessing Cat Flea Microbiomes in Northern and Southern California by 16S rRNA Next-Generation Sequencing.

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Vasconcelos, Elton J R; Billeter, Sarah A; Jett, Lindsey A; Meinersmann, Richard J; Barr, Margaret C; Diniz, Pedro P V P; Oakley, Brian B

2018-06-12

Flea-borne diseases (FBDs) impact both human and animal health worldwide. Because adult fleas are obligately hematophagous and can harbor potential pathogens, fleas act as ectoparasites of vertebrates, as well as zoonotic disease vectors. Cat fleas (Ctenocephalides felis) are important vectors of two zoonotic bacterial genera listed as priority pathogens by the National Institute of Allergy and Infectious Diseases (NIAID-USA): Bartonella spp. and Rickettsia spp., causative agents of bartonelloses and rickettsioses, respectively. In this study, we introduce the first microbiome analysis of C. felis samples from California, determining the presence and abundance of relevant pathogenic genera by characterizing the cat flea microbiome through 16S rRNA next-generation sequencing (16S-NGS). Samples from both northern (NoCal) and southern (SoCal) California were assessed to expand current knowledge regarding FBDs in the state. We identified Rickettsia and Bartonella, as well as the endosymbiont Wolbachia, as the most abundant genera, followed by less abundant taxa. In comparison to our previous study screening Californian cat fleas for rickettsiae using PCR/digestion/sequencing of the ompB gene, the 16S-NGS approach applied herein showed a 95% level of agreement in detecting Rickettsia spp. There was no overall difference in microbiome diversity between NoCal and SoCal samples. Bacterial taxa identified by 16S-NGS in this study may help to improve epidemiological investigations, pathogen surveillance efforts, and clinical diagnostics of FBDs in California and elsewhere.

Prevalence of fleas and gastrointestinal parasites in free-roaming cats in central Mexico.

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Germinal J Cantó

Full Text Available The prevalence of fleas and gastrointestinal parasites in free-roaming and domestic cats in central Mexico was evaluated. Three hundred and fifty eight cats captured in the street or brought in by owners to the Animal Control Center Unit, a unit of State Government, from June 2010 to May 2011, were included in the study. All cats were examined for the presence of fleas and gastrointestinal worms. One-hundred and ninety (53% cats were infested with at least one flea species. Single infestations were observed in 106 (30% cats and mixed infestations in 84 (23% cats. Four species of fleas were recovered: Ctenocephalides felis in 53% of the cats, C. canis in 18%, Echidnophaga gallinacea in 7% and Pulex irritans in 1%. One-hundred and sixty three (45% cats were infected with one or more species of gastrointestinal parasites: 48 (13% with nematodes, 145 (40% with cestodes, and one animal presented Moniliformis moniliformis. Prevalences and mean intensity of infection were: Physaloptera praeputialis 7 and 18; T. cati 3 and 2; Ancylostoma tubaeforme 2.5 and 2; Toxascaris leonina 0.5 and 2; Dipylidium caninum 36 and 32; Taenia taeniformis 4 and 3 and Moniliformis moniliformis 0.3 and 106, respectively. There was significant association (P0.05. The correlation between the total number of ectoparasites and endoparasites was not significant (r = 0.089, P = 0.094.

Prevalence of Fleas and Gastrointestinal Parasites in Free-Roaming Cats in Central Mexico

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Cantó, Germinal J.; Guerrero, Roberto I.; Olvera-Ramírez, Andrea M.; Milián, Feliciano; Mosqueda, Juan; Aguilar-Tipacamú, Gabriela

2013-01-01

The prevalence of fleas and gastrointestinal parasites in free-roaming and domestic cats in central Mexico was evaluated. Three hundred and fifty eight cats captured in the street or brought in by owners to the Animal Control Center Unit, a unit of State Government, from June 2010 to May 2011, were included in the study. All cats were examined for the presence of fleas and gastrointestinal worms. One-hundred and ninety (53%) cats were infested with at least one flea species. Single infestations were observed in 106 (30%) cats and mixed infestations in 84 (23%) cats. Four species of fleas were recovered: Ctenocephalides felis in 53% of the cats, C. canis in 18%, Echidnophaga gallinacea in 7% and Pulex irritans in 1%. One-hundred and sixty three (45%) cats were infected with one or more species of gastrointestinal parasites: 48 (13%) with nematodes, 145 (40%) with cestodes, and one animal presented Moniliformis moniliformis. Prevalences and mean intensity of infection were: Physaloptera praeputialis 7 and 18; T. cati 3 and 2; Ancylostoma tubaeforme 2.5 and 2; Toxascaris leonina 0.5 and 2; Dipylidium caninum 36 and 32; Taenia taeniformis 4 and 3 and Moniliformis moniliformis 0.3 and 106, respectively. There was significant association (P0.05). The correlation between the total number of ectoparasites and endoparasites was not significant (r = 0.089, P = 0.094). PMID:23573282

Effects on the development of Dipylidium caninum and on the host reaction to this parasite in the adult flea (Ctenocephalides felis felis).

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Pugh, R E

1987-01-01

Temperature was found to be a major factor affecting the development of Dipylidium caninum and the presence of a host reaction of adult Ctenocephalides felis felis to D. caninum. Adult fleas reared at 30-32 degrees C contained fully developed metacestodes when they emerged from their cocoons. However at lower temperatures, D. caninum could not complete development until the flea hosts had spent some time on their mammalian hosts. It was the surface temperature of the mammals (31-36 degrees C) and not the fleas' blood meals which resulted in the metacestodes completing their development. This development of D. caninum was therefore independent of the flea development. At 20 degrees C, a larger and more prolonged host reaction was mounted than at higher temperatures. The larval flea diet had a small effect on the subsequent cestode development and the adult fleas' reaction to it.

Evaluation of sarolaner and spinosad oral treatments to eliminate fleas, reduce dermatologic lesions and minimize pruritus in naturally infested dogs in west Central Florida, USA.

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Dryden, Michael W; Canfield, Michael S; Niedfeldt, Emily; Kinnon, Amanda; Kalosy, Kimberly; Smith, Amber; Foley, Kaitlin M; Smith, Vicki; Bress, Todd S; Smith, Nicole; Endrizzi, Mike; Login, Joyce

2017-08-17

An in-home investigation of naturally flea infested dogs was conducted in West Central Florida, USA to evaluate and compare the effectiveness of two different oral flea adulticides to control flea infestations, minimize dermatologic lesions and reduce pruritus over an 8-week period. Twenty-nine dogs living in 19 homes and another 26 dogs residing in 16 different homes were orally administered either a sarolaner or spinosad chewable, respectively on day 0 and once between days 28-30. Products were administered by study personnel according to label directions. Flea populations on dogs were estimated using visual area counts and flea infestations in the indoor premises were assessed using intermittent-light flea traps on days 0, 7, 14, 21 and once between days 28-30, 40-45, and 56-60. Assessments of dermatologic lesions were conducted monthly during the study and severity of pruritus was evaluated throughout the study on the same schedule as flea counts were conducted. Concurrent treatments for existing skin disease were not allowed. The administration of sarolaner or spinosad reduced flea populations on dogs by 99.0% and 97.3%, respectively within 7 days. Flea infestations on the sarolaner- and spinosad-treated dogs were reduced by > 99% at every counting period from day 14 post-treatment through the end of the 8-week study. At the end of the study 96.4 and 92.0% of the dogs treated with sarolaner and spinosad, respectively were flea-free. Flea populations in the indoor premises were also markedly reduced the end of the study, with 100 and 99.8% reductions in flea trap counts in the sarolaner and spinosad treatment groups, respectively. FAD lesion scores, atopic dermatitis lesions scores (CADESI-4) and pruritus severity scores were also markedly improved with both formulations. An in-home clinical field study conducted during the summer of 2016 in subtropical Florida demonstrated that two-monthly administrations of either sarolaner or spinosad chewables almost

Coexistence of Bartonella henselae and B. clarridgeiae in populations of cats and their fleas in Guatemala.

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Bai, Ying; Rizzo, Maria Fernanda; Alvarez, Danilo; Moran, David; Peruski, Leonard F; Kosoy, Michael

2015-12-01

Cats and their fleas collected in Guatemala were investigated for the presence of Bartonella infections. Bartonella bacteria were cultured from 8.2% (13/159) of cats, and all cultures were identified as B. henselae. Molecular analysis allowed detection of Bartonella DNA in 33.8% (48/142) of cats and in 22.4% (34/152) of cat fleas using gltA, nuoG, and 16S-23S internal transcribed spacer targets. Two Bartonella species, B. henselae and B. clarridgeiae, were identified in cats and cat fleas by molecular analysis, with B. henselae being more common than B. clarridgeiae in the cats (68.1%; 32/47 vs 31.9%; 15/47). The nuoG was found to be less sensitive for detecting B. clarridgeiae compared with other molecular targets and could detect only two of the 15 B. clarridgeiae-infected cats. No significant differences were observed for prevalence between male and female cats and between different age groups. No evident association was observed between the presence of Bartonella species in cats and in their fleas. © 2015 The Society for Vector Ecology.

Evaluation of the speed of kill, effects on reproduction, and effectiveness in a simulated infested-home environment of sarolaner (Simparica™) against fleas on dogs.

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Six, Robert H; Becskei, Csilla; Carter, Lori; Gale, Boyd; Young, David R; Mahabir, Sean P; Chapin, Sara; Myers, Melanie R

2016-05-30

Four studies were conducted to evaluate the speed of kill, effect on egg production, and efficacy in a simulated infested-home environment of a novel isoxazoline, sarolaner (Simparica™, Zoetis), against fleas on dogs. Individually identified and housed, purpose-bred Beagles were used in each study and were allocated randomly to groups based on pretreatment parasite counts. In two speed of kill studies, groups of dogs infested with 100 fleas prior to treatment were treated orally with placebo or sarolaner tablets providing the minimum dose of 2mg/kg and then re-infested with fleas weekly for five weeks post-treatment. Comb counts were conducted to determine the numbers of viable fleas at one to three, four, eight and 12h after treatment and each subsequent infestation. In the egg production study, sarolaner- and placebo-treated dogs were similarly challenged with fleas and at 48h after each infestation the dogs were housed for 20h in cages allowing the collection and counting of all flea eggs produced during this period. Collected eggs were incubated to evaluate hatch and development to adults. The last study used dogs housed in a flea-infested simulated-home environment. Dogs were allocated to treatment with either placebo or sarolaner tablets providing a dose of 2mg/kg once a month for three treatments. Flea infestations were assessed by comb counts (fleas were replaced on the dogs) on Days 14, 30, 44, 60, 74 and 90. The speed of kill studies demonstrated that a single 2mg/kg oral dose of sarolaner started killing fleas within three to four hours after treatment or subsequent re-infestations for up to a month, and achieved ≥98% control of fleas by eight hours after treatment or re-infestation for 28 days. In the study to assess effects on flea reproduction, a single oral treatment of sarolaner resulted in the complete cessation of egg-laying for 35 days. This rapid kill of fleas and inhibition of reproduction were confirmed in a simulated-home environment

Fleas, hosts and habitat: What can we predict about the spread of vector-borne zoonotic diseases?

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Megan M. Friggens

2010-01-01

Vector-borne diseases of humans and wildlife are experiencing resurgence across the globe. I examine the dynamics of flea borne diseases through a comparative analysis of flea literature and analyses of field data collected from three sites in New Mexico: The Sevilleta National Wildlife Refuge, the Sandia Mountains and the Valles Caldera National Preserve (VCNP). My...

First report of a Rickettsia asembonensis related infecting fleas in Brazil.

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Silva, Arannadia Barbosa; Vizzoni, Vinicius Figueiredo; Costa, Andréa Pereira; Costa, Francisco Borges; Moraes-Filho, Jonas; Labruna, Marcelo Bahia; Gazêta, Gilberto Salles; de Maria Seabra Nogueira, Rita

2017-08-01

The present study was performed in a non-endemic area for spotted fever (SF) in Imperatriz microregion, state of Maranhão, Brazil. Blood samples and ectoparasites were collected from 300 dogs of the Imperatriz microregion. Canine serum samples were tested individually by indirect immunofluorescence assay (IFA), using five Rickettsia isolates from Brazil. Antibodies reactive to at least one of the five species of Rickettsia were detected in 1.6% of the dogs (5/300). These sera were considered reactive to Rickettsia rickettsii and Rickettsia amblyommatis or very closely related species. The ticks (Acari: Ixodidae), identified as Rhipicephalus sanguineus sensu lato (Latreille), and the fleas, identified as Ctenocephalides felis, were tested by polymerase chain reaction (PCR) for detection of rickettsial DNA. More than 78% (83/106) of the C. felis fleas were found to be infected with Rickettsia species using gltA as rickettsial PCR targets, whereas no evidence of Rickettsia spp. was found in R. sanguineus s. l. Genetic analysis based on genes gltA, htrA and ompB showed that the detected strain, is most closely related to Rickettsia asembonensis (formerly Candidatus Rickettsia asemboensis). The present study is the first report of a R. asembonensis related infecting C. felis fleas in Brazil. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of planting dates and insecticide strategies for managing crucifer flea beetles (Coleoptera: Chrysomelidae) in spring-planted canola.

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Knodel, Janet J; Olson, Denise L; Hanson, Bryan K; Henson, Robert A

2008-06-01

Integration of cultural practices, such as planting date with insecticide-based strategies, was investigated to determine best management strategy for flea beetles (Phyllotreta spp.) (Coleoptera: Chrysomelidae) in canola (Brassica napus L.). We studied the effect of two spring planting dates of B. napus and different insecticide-based management strategies on the feeding injury caused by fleabeetles in North Dakota during 2002-2003. Adult beetle peak emergence usually coincided with the emergence of the early planted canola, and this resulted in greater feeding injury in the early planted canola than later planted canola. Use of late-planted canola may have limited potential for cultural control of flea beetle, because late-planted canola is at risk for yield loss due to heat stress during flowering. Flea beetle injury ratings declined when 1) the high rate of insecticide seed treatment plus a foliar insecticide applied 21 d after planting was used, 2) the high rate of insecticide seed treatment only was used, or 3) two foliar insecticide sprays were applied. These insecticide strategies provided better protection than the low rates of insecticide seed treatments or a single foliar spray, especially in areas with moderate-to-high flea beetle populations. The foliar spray on top of the seed treatment controlled later-emerging flea beetles as the seed treatment residual was diminishing and the crop became vulnerable to feeding injury. The best insecticide strategy for management of flea beetle was the high rate of insecticide seed treatment plus a foliar insecticide applied at 21 d after planting, regardless of planting date.

Modelling the current distribution and predicted spread of the flea species Ctenocephalides felis infesting outdoor dogs in Spain.

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Gálvez, Rosa; Musella, Vicenzo; Descalzo, Miguel A; Montoya, Ana; Checa, Rocío; Marino, Valentina; Martín, Oihane; Cringoli, Giuseppe; Rinaldi, Laura; Miró, Guadalupe

2017-09-19

The cat flea, Ctenocephalides felis, is the most prevalent flea species detected on dogs and cats in Europe and other world regions. The status of flea infestation today is an evident public health concern because of their cosmopolitan distribution and the flea-borne diseases transmission. This study determines the spatial distribution of the cat flea C. felis infesting dogs in Spain. Using geospatial tools, models were constructed based on entomological data collected from dogs during the period 2013-2015. Bioclimatic zones, covering broad climate and vegetation ranges, were surveyed in relation to their size. The models builded were obtained by negative binomial regression of several environmental variables to show impacts on C. felis infestation prevalence: land cover, bioclimatic zone, mean summer and autumn temperature, mean summer rainfall, distance to urban settlement and normalized difference vegetation index. In the face of climate change, we also simulated the future distributions of C. felis for the global climate model (GCM) "GFDL-CM3" and for the representative concentration pathway RCP45, which predicts their spread in the country. Predictive models for current climate conditions indicated the widespread distribution of C. felis throughout Spain, mainly across the central northernmost zone of the mainland. Under predicted conditions of climate change, the risk of spread was slightly greater, especially in the north and central peninsula, than for the current situation. The data provided will be useful for local veterinarians to design effective strategies against flea infestation and the pathogens transmitted by these arthropods.

Comparative efficacy on dogs of a single topical treatment with fipronil/(S-methoprene or weekly physiological hygiene shampoos against Ctenocephalides felis in a simulated flea-infested environment

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Beugnet F.

2012-05-01

Full Text Available Flea infestations of pets continue to persist due to the lack of knowledge of flea biology and ecology. It is not unusual that pet owners believe regular hygiene, such as shampooing their dogs can replace regular insecticidal treatment. The objective of this study was to compare in a flea simulated environment, modelling exposure similar to that found in a home, that the use of regular physiological shampoo does not control fleas adequately when compared to a long acting topical formulation. Three groups of six dogs were formed: one untreated control group, one group treated monthly with the topical formulation of fipronil/(S-methoprene, and a third group treated weekly with a hygiene shampoo. All dogs were infested with adult unfed Ctenocephalides felis fleas (200 ± 5 on Days -28 and -21. Each animal’s sleeping box was fitted with a plastic cup mounted to the inside roof of the box. The sleeping bench of each animal was covered with a carpet to accommodate flea development. The dogs were maintained in their kennels throughout the study. In order to maintain the environmental flea challenge, C. felis pupae (100 ± 5 were placed in the plastic cup in each animal’s sleeping box on Days -14, -7, 0, 7, 14, 21, 28, 35 and 42. The dogs were combed and fleas counted weekly on Days -1, 3, 10, 17, 24, 31, 38, 45, and 51. The fleas were placed immediately back on the dogs. On Day 60, fleas were counted and removed. Flea infestations in the untreated control group at each count averaged between 46.2 and 74.2 fleas throughout the study. The average number of fleas infesting dogs was significantly different (p < 0.05 between the untreated and the two treatment groups and between the two treatment groups at all counts throughout the two months study (Days 3, 10, 17, 24, 31, 38, 45, 51 and 60. The efficacy was never below 99.1% in the fipronil/(S-methoprene group, and efficacy in the shampoo group was never above 79.2%. Weekly shampooing in treatment

Predicting small mammal and flea abundance using landform and soil properties in a plague endemic area in Lushoto District, Tanzania.

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Meliyo, Joel L; Kimaro, Didas N; Msanya, Balthazar M; Mulungu, Loth S; Hieronimo, Proches; Kihupi, Nganga I; Gulinck, Hubert; Deckers, Jozef A

2014-07-01

Small mammals particularly rodents, are considered the primary natural hosts of plague. Literature suggests that plague persistence in natural foci has a root cause in soils. The objective of this study was to investigate the relationship between on the one hand landforms and associated soil properties, and on the other hand small mammals and fleas in West Usambara Mountains in Tanzania, a plague endemic area. Standard field survey methods coupled with Geographical Information System (GIS) technique were used to examine landform and soils characteristics. Soil samples were analysed in the laboratory for physico-chemical properties. Small mammals were trapped on pre-established landform positions and identified to genus/species level. Fleas were removed from the trapped small mammals and counted. Exploration of landform and soil data was done using ArcGIS Toolbox functions and descriptive statistical analysis. The relationships between landforms, soils, small mammals and fleas were established by generalised linear regression model (GLM) operated in R statistics software. Results show that landforms and soils influence the abundance of small mammals and fleas and their spatial distribution. The abundance of small mammals and fleas increased with increase in elevation. Small mammal species richness also increases with elevation. A landform-soil model shows that available phosphorus, slope aspect and elevation were statistically significant predictors explaining richness and abundance of small mammals. Fleas' abundance and spatial distribution were influenced by hill-shade, available phosphorus and base saturation. The study suggests that landforms and soils have a strong influence on the richness and evenness of small mammals and their fleas' abundance hence could be used to explain plague dynamics in the area.

Efficacy of fluralaner flavored chews (Bravecto) administered to dogs against the adult cat flea, Ctenocephalides felis felis and egg production.

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Dryden, Michael W; Smith, Vicki; Bennett, Tashina; Math, Lisa; Kallman, James; Heaney, Kathleen; Sun, Fangshi

2015-07-11

Fluralaner is a potent insecticide and acaricide with rapid and persistent efficacy. This study measured the efficacy of fluralaner flavored chews (Bravecto®, Merck Animal Health) administered to dogs against adult Ctenocephalides felis felis and egg production. Twelve purpose-bred dogs were randomly allocated to two groups of six dogs each. Dogs in treatment group 1 were administered a single fluralaner flavored chew to achieve a minimum dose of at least 25 mg/kg while treatment group 2 served as untreated controls. On Days -2, 28, 56, 84, 91, 98, 105, 112, and 120 post-treatment, each dog was infested with approximately 200 unfed cat fleas, C. felis felis (KS1 strain). Forty-eight hours after treatment and 48 h after each infestation, eggs were collected over a 3-h period, counted and viability determined. Dogs were combed to remove any remaining fleas. Treatment of dogs with oral fluralaner provided a 100% reduction in flea counts 48 h after treatment and within 48 h of every post-treatment infestation through Day122. Egg production from fluralaner treated dogs was reduced by 99.9% (two eggs from one dog) within 48 h after treatment and not a single egg (100% efficacy) was thereafter collected from treated dogs. Adult flea counts and egg production from the fluralaner-treated dogs were significantly lower than for non-treated controls at all post-treatment evaluations (P dog 48 h after treatment did not produce any adult fleas. As no additional eggs were collected from treated dogs, no viability assessment was performed. A single oral dose of fluralaner flavored chews provided 100% efficacy against repeated flea infestations on dogs for 4 months. Fluralaner reduced egg production of activity reproducing female fleas by 99.9% and then killed every single female flea before any eggs could be produced following each subsequent re-infestation for the entire 122-day evaluation period.

Small todents fleas from the bubonic plague focus located in the Serra dos Órgãos Mountain Range, State of Rio de Janeiro, Brazil

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Raimundo Wilson de Carvalho

2001-07-01

Full Text Available Eleven species of fleas were collected from 601 small rodents, from November 1995 to October 1997, in areas of natural focus of bubonic plague, including the municipalities of Nova Friburgo, Sumidouro and Teresópolis, State of Rio de Janeiro, Brazil. Among 924 fleas collected, Polygenis (Polygenis rimatus (Rhopalopsyllidae was the predominant species regarding the frequency, representing 41.3% (N:382, followed by P. (Neopolygenis pradoi, representing 20% (N:185 and Craneopsylla minervaminerva (Stephanocircidae, representing 18.9% (N:175. The host Akodon cursor harbored 47.9% of these fleas. Other six host species were infested by 52.1% of the remaining fleas. Fleas were found on hosts and in places within the focus not previously reported by the literature.

Efficacy and safety of sarolaner (Simparica™) against fleas on dogs presented as veterinary patients in the United States.

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Cherni, Judith A; Mahabir, Sean P; Six, Robert H

2016-05-30

The efficacy and safety of a novel isoxazoline parasiticide, sarolaner (Simparica™), for the control of fleas on dogs was evaluated in a randomized, controlled clinical study conducted in 19 general veterinary practices throughout the United States. Four hundred and seventy nine (479) dogs from 293 households were enrolled. Each household was randomly assigned to treatment with either sarolaner oral tablets (Simparica™, Zoetis) at the proposed label dose or an approved comparator product at the label dose (spinosad, Comfortis(®), Elanco). Dogs were dosed by their owners at home on Day 0 and on approximately Days 30 and 60. Dogs were examined at the clinics for general health, flea and tick infestation, and clinical signs of flea allergy dermatitis (FAD) at the initial visit and Days 14, 30, 60 and 90. Blood was collected for clinical pathology at screening and Day 90. Sarolaner was well-accepted by dogs with the majority of flavored chewable tablets (91.5%) accepted free choice, by hand or in food. Geometric mean live flea counts were reduced by >99% at the first time measured (14 days) after initiation of treatment and continued to reduce through the study. Treatment success (proportion of dogs with ≥90% reduction in fleas) for the sarolaner-treated dogs was superior to that for spinosad-treated dogs at Days 14 and 30 and non-inferior on Days 60 and 90 (P≤0.025) The rapid reduction in flea infestations resulted in a similar rapid resolution of the clinical signs associated with FAD. Sarolaner chewable tablets were well tolerated with no treatment related adverse reactions. Most of the clinical signs reported were consistent with allergies and dermatitis or sporadic occurrences of conditions commonly observed in the general dog population. A wide variety of concomitant medications, including many commercially available heartworm preventatives and other anthelmintic drugs, were administered to study dogs and all were well tolerated. Sarolaner administered

Detection of Rickettsia in Rhipicephalus sanguineus Ticks and Ctenocephalides felis Fleas from Southeastern Tunisia by Reverse Line Blot Assay

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Khrouf, Fatma; M'Ghirbi, Youmna; Znazen, Abir; Ben Jemaa, Mounir; Hammami, Adnene

2014-01-01

Ticks (n = 663) and fleas (n = 470) collected from domestic animals from southeastern Tunisia were screened for Rickettsia infection using reverse line blot assay. Evidence of spotted fever group Rickettsia was obtained. We detected Rickettsia felis in fleas, Rickettsia massiliae Bar 29 and the Rickettsia conorii Israeli spotted fever strain in ticks, and Rickettsia conorii subsp. conorii and Rickettsia spp. in both arthropods. The sensitivity of the adopted technique allowed the identification of a new association between fleas and R. conorii subsp. conorii species. The presence of these vector-borne Rickettsia infections should be considered when diagnosing this disease in humans in Tunisia. PMID:24226919

Insect ectoparasites from wild passerine birds in the Czech Republic

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Sychra O.

2008-12-01

Full Text Available Wild passerine birds (Passeriformes from northeastern part of the Czech Republic were examined for ectoparasites. Three species of louse-flies of the genus Ornithomya (Diptera: Hippoboscidae, two species of fleas of the genera Ceratophyllus and Dasypsyllus (Siphonaptera: Ceratophyllidae, and 15 species of chewing lice belonging to the genera Myrsidea, Menacanthus (Phthiraptera: Menoponidae, Brueelia, Penenirmus, Philopterus (Phthiraptera: Philopteridae were found on 82 birds of 23 species. New chewing louse-host records are Hippolais icterina for Menacanthus currucae; Motacilla cinerea for Menacanthus pusillus; Turdus philomelos and Motacilla cinerea for Brueelia merulensis; and Sylvia atricapilla for Menacanthus eurysternus. Brueelia neoatricapillae is cited for the first time for the Czech Republic. Parasitological parameters such as prevalence, intensity and abundance are also discussed.

A survey of cats and dogs for fleas: with particular reference to their role as intermediate hosts of Dipylidium caninum.

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Guzman, R F

1984-05-01

Three species of fleas, viz. Ctenocephalides felis, Ctenocephalides canis, and Pulex irritans were found in an examination of 81 cats and 48 dogs in Wellington. C. felis was the most prevalent flea in cats, and C. canis predominated in dogs. It is speculated that C. felis, and its primary host the cat, may assume greater medical and veterinary significance than C. canis. In an examination of 1578 fleas for cysticercoids of the dog tapeworm, Dipylidium caninum, all were found negative. These results do not necessarily reflect the availability of cysticercoids in the environment, and the reasons for this are discussed.

Absence of zoonotic Bartonella species in questing ticks: First detection of Bartonella clarridgeiae and Rickettsia felis in cat fleas in the Netherlands

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Reimerink Johan R

2011-04-01

Full Text Available Abstract Background Awareness for flea- and tick-borne infections has grown in recent years and the range of microorganisms associated with these ectoparasites is rising. Bartonella henselae, the causative agent of Cat Scratch Disease, and other Bartonella species have been reported in fleas and ticks. The role of Ixodes ricinus ticks in the natural cycle of Bartonella spp. and the transmission of these bacteria to humans is unclear. Rickettsia spp. have also been reported from as well ticks as also from fleas. However, to date no flea-borne Rickettsia spp. were reported from the Netherlands. Here, the presence of Bartonellaceae and Rickettsiae in ectoparasites was investigated using molecular detection and identification on part of the gltA- and 16S rRNA-genes. Results The zoonotic Bartonella clarridgeiae and Rickettsia felis were detected for the first time in Dutch cat fleas. B. henselae was found in cat fleas and B. schoenbuchensis in ticks and keds feeding on deer. Two Bartonella species, previously identified in rodents, were found in wild mice and their fleas. However, none of these microorganisms were found in 1719 questing Ixodes ricinus ticks. Notably, the gltA gene amplified from DNA lysates of approximately 10% of the questing nymph and adult ticks was similar to that of an uncultured Bartonella-related species found in other hard tick species. The gltA gene of this Bartonella-related species was also detected in questing larvae for which a 16S rRNA gene PCR also tested positive for "Candidatus Midichloria mitochondrii". The gltA-gene of the Bartonella-related species found in I. ricinus may therefore be from this endosymbiont. Conclusions We conclude that the risk of acquiring Cat Scratch Disease or a related bartonellosis from questing ticks in the Netherlands is negligible. On the other hand fleas and deer keds are probable vectors for associated Bartonella species between animals and might also transmit Bartonella spp. to humans.

Grooming behaviors of black-tailed prairie dogs are influenced by flea parasitism, conspecifics, and proximity to refuge

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Eads, David A.; Biggins, Dean E.; Eads, Samantha L.

2017-01-01

Grooming is a common animal behavior that aids in ectoparasite defense. Ectoparasites can stimulate grooming, and natural selection can also favor endogenous mechanisms that evoke periodic bouts of “programmed” grooming to dislodge or kill ectoparasites before they bite or feed. Moreover, grooming can function as a displacement or communication behavior. We compared the grooming behaviors of adult female black-tailed prairie dogs (Cynomys ludovicianus) on colonies with or without flea control via pulicide dust. Roughly 91% of the prairie dogs sampled on the non-dusted colony carried at least one flea, whereas we did not find fleas on two dusted colonies. During focal observations, prairie dogs on the non-dusted colony groomed at higher frequencies and for longer durations than prairie dogs on the dusted colonies, lending support to the hypothesis that fleas stimulated grooming. However, the reduced amount of time spent grooming on the dusted colonies suggested that approximately 25% of grooming might be attributed to factors other than direct stimulation from ectoparasites. Non-dusted colony prairie dogs rarely autogroomed when near each other. Dusted colony prairie dogs autogroomed for shorter durations when far from a burrow opening (refuge), suggesting a trade-off between self-grooming and antipredator defense. Allogrooming was detected only on the non-dusted colony and was limited to adult females grooming young pups. Grooming appears to serve an antiparasitic function in C. ludovicianus. Antiparasitic grooming might aid in defense against fleas that transmit the plague bacterium Yersinia pestis. Plague was introduced to North America ca. 1900 and now has a strong influence on most prairie dog populations, suggesting a magnified effect of grooming on prairie dog fitness.

Identification, cloning, and characterization of a major cat flea salivary allergen (Cte f 1).

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McDermott, M J; Weber, E; Hunter, S; Stedman, K E; Best, E; Frank, G R; Wang, R; Escudero, J; Kuner, J; McCall, C

2000-05-01

An 18 kDa protein isolated from saliva of the cat flea, Ctenocephalides felis, elicits a positive intradermal skin test (IDST) in 100 and 80% of experimental and clinical flea allergic dogs, respectively. Using solid-phase enzyme-linked immuno assay (ELISA), this protein detected IgE in 100 and 80% of experimental and clinical flea allergic dogs, respectively. A cDNA (pFSI) encoding a full-length Cte f 1 protein was isolated from a C. felis salivary gland cDNA library, using a combination of PCR and hybridization screening. This cDNA is 658 bp in length, and contains an open reading frame of 528 bp. The open reading frame encodes a protein of 176 amino acids, consisting of an 18 amino acid signal sequence and a 158 amino acid mature protein. The calculated molecular weight and pI of the mature protein are 18106 Da and 9.3, respectively. The protein, named Cte f 1, is the first novel major allergen described for canine flea allergy. Recombinant Cte f 1 (rCte f 1) was expressed in Escherichia coli, Pichia pastoris and baculovirus infected Trichoplusia ni cells. Approximately, 90% of the rCte f 1 expressed in E. coli accumulated in insoluble inclusion bodies, which could be refolded to a soluble mixture of disulfide isomers with partial IgE binding activity. Small quantities of an apparently correctly refolded form of rCte f 1, which had IgE binding activity equal to the native antigen, was isolated from the soluble fraction of E. coli cells. However, P. pastoris and baculovirus infected insect cells expressed and secreted a fully processed, correctly refolded and fully active form of rCte f 1. Mass spectrometry analysis of the active forms of rCte f 1confirmed that eight intact disulfide bonds were present, matching the number observed in the native allergen. The relative ability of rCte f 1 to bind IgE in the serum of flea allergic animals, produced in these three expression systems, matched that of the native allergen. Competition ELISA demonstrated that

Prevalence of Yersinia pestis in rodents and fleas associated with black-tailed prairie dogs (Cynomys ludovicianus) at Thunder Basin National Grassland, Wyoming

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Thiagarajan, Bala; Bai, Ying; Gage, Kenneth L.; Cully, Jack F.

2008-01-01

Rodents (and their fleas) that are associated with prairie dogs are considered important for the maintenance and transmission of the bacterium (Yersinia pestis) that causes plague. Our goal was to identify rodent and flea species that were potentially involved in a plague epizootic in black-tailed prairie dogs at Thunder Basin National Grassland. We collected blood samples and ectoparasites from rodents trapped at off- and on-colony grids at Thunder Basin National Grassland between 2002 and 2004. Blood samples were tested for antibodies to Y. pestis F-1 antigen by a passive hemagglutination assay, and fleas were tested by a multiplex polymerase chain reaction, for the presence of the plague bacterium. Only one of 1,421 fleas, an Oropsylla hirsuta collected in 2002 from a deer mouse, Peromyscus maniculatus, tested positive for Y. pestis. Blood samples collected in summer 2004 from two northern grasshopper mice, Onychomys leucogaster, tested positive for Y. pestis antibodies. All three positive samples were collected from on-colony grids shortly after a plague epizootic occurred. This study confirms that plague is difficult to detect in rodents and fleas associated with prairie dog colonies, unless samples are collected immediately after a prairie dog die-off.

Parasite spread at the domestic animal - wildlife interface: anthropogenic habitat use, phylogeny and body mass drive risk of cat and dog flea (Ctenocephalides spp.) infestation in wild mammals.

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Clark, Nicholas J; Seddon, Jennifer M; Šlapeta, Jan; Wells, Konstans

2018-01-08

Spillover of parasites at the domestic animal - wildlife interface is a pervasive threat to animal health. Cat and dog fleas (Ctenocephalides felis and C. canis) are among the world's most invasive and economically important ectoparasites. Although both species are presumed to infest a diversity of host species across the globe, knowledge on their distributions in wildlife is poor. We built a global dataset of wild mammal host associations for cat and dog fleas, and used Bayesian hierarchical models to identify traits that predict wildlife infestation probability. We complemented this by calculating functional-phylogenetic host specificity to assess whether fleas are restricted to hosts with similar evolutionary histories, diet or habitat niches. Over 130 wildlife species have been found to harbour cat fleas, representing nearly 20% of all mammal species sampled for fleas. Phylogenetic models indicate cat fleas are capable of infesting a broad diversity of wild mammal species through ecological fitting. Those that use anthropogenic habitats are at highest risk. Dog fleas, by contrast, have been recorded in 31 mammal species that are primarily restricted to certain phylogenetic clades, including canids, felids and murids. Both flea species are commonly reported infesting mammals that are feral (free-roaming cats and dogs) or introduced (red foxes, black rats and brown rats), suggesting the breakdown of barriers between wildlife and invasive reservoir species will increase spillover at the domestic animal - wildlife interface. Our empirical evidence shows that cat fleas are incredibly host-generalist, likely exhibiting a host range that is among the broadest of all ectoparasites. Reducing wild species' contact rates with domestic animals across natural and anthropogenic habitats, together with mitigating impacts of invasive reservoir hosts, will be crucial for reducing invasive flea infestations in wild mammals.

Yersinia pestis insecticidal-like toxin complex (Tc family proteins: characterization of expression, subcellular localization, and potential role in infection of the flea vector

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Spinner Justin L

2012-12-01

Full Text Available Abstract Background Toxin complex (Tc family proteins were first identified as insecticidal toxins in Photorhabdus luminescens and have since been found in a wide range of bacteria. The genome of Yersinia pestis, the causative agent of bubonic plague, contains a locus that encodes the Tc protein homologues YitA, YitB, YitC, and YipA and YipB. Previous microarray data indicate that the Tc genes are highly upregulated by Y. pestis while in the flea vector; however, their role in the infection of fleas and pathogenesis in the mammalian host is unclear. Results We show that the Tc proteins YitA and YipA are highly produced by Y. pestis while in the flea but not during growth in brain heart infusion (BHI broth at the same temperature. Over-production of the LysR-type regulator YitR from an exogenous plasmid increased YitA and YipA synthesis in broth culture. The increase in production of YitA and YipA correlated with the yitR copy number and was temperature-dependent. Although highly synthesized in fleas, deletion of the Tc proteins did not alter survival of Y. pestis in the flea or prevent blockage of the proventriculus. Furthermore, YipA was found to undergo post-translational processing and YipA and YitA are localized to the outer membrane of Y. pestis. YitA was also detected by immunofluorescence microscopy on the surface of Y. pestis. Both YitA and YipA are produced maximally at low temperature but persist for several hours after transfer to 37°C. Conclusions Y. pestis Tc proteins are highly expressed in the flea but are not essential for Y. pestis to stably infect or produce a transmissible infection in the flea. However, YitA and YipA localize to the outer membrane and YitA is exposed on the surface, indicating that at least YitA is present on the surface when Y. pestis is transmitted into the mammalian host from the flea.

Development of a loop-mediated isothermal amplification (LAMP) assay for rapid screening of ticks and fleas for spotted fever group rickettsia.

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Noden, Bruce H; Martin, Jaclyn; Carrillo, Yisel; Talley, Justin L; Ochoa-Corona, Francisco M

2018-01-01

The importance of tick and flea-borne rickettsia infections is increasingly recognized worldwide. While increased focus has shifted in recent years to the development of point-of-care diagnostics for various vector-borne diseases in humans and animals, little research effort has been devoted to their integration into vector surveillance and control programs, particularly in resource-challenged countries. One technology which may be helpful for large scale vector surveillance initiatives is loop-mediated isothermal amplification (LAMP). The aim of this study was to develop a LAMP assay to detect spotted fever group (SFG) rickettsia DNA from field-collected ticks and fleas and compare with published end-point PCR results. A Spotted Fever Group rickettsia-specific loop-mediated isothermal amplification (SFGR-LAMP) assay was developed using primers based on a region of the R. rickettsii 17kDa protein gene. The sensitivity, specificity, and reproducibility of the assay were evaluated. The assay was then compared with the results of end-point PCR assays for pooled tick and flea samples obtained from field-based surveillance studies. The sensitivity of the SFGR-LAMP assay was 0.00001 ng/μl (25μl volume) which was 10 times more sensitive than the 17kDa protein gene end-point PCR used as the reference method. The assay only recognized gDNA from SFG and transitional group (TRG) rickettsia species tested but did not detect gDNA from typhus group (TG) rickettsia species or closely or distantly related bacterial species. The SFGR-LAMP assay detected the same positives from a set of pooled tick and flea samples detected by end-point PCR in addition to two pooled flea samples not detected by end-point PCR. To our knowledge, this is the first study to develop a functional LAMP assay to initially screen for SFG and TRG rickettsia pathogens in field-collected ticks and fleas. With a high sensitivity and specificity, the results indicate the potential use as a field

Two Pathogens and One Disease: Detection and Identification of Flea-Borne Rickettsiae in Areas Endemic for Murine Typhus in California

Science.gov (United States)

EREMEEVA, MARINA E.; KARPATHY, SANDOR E.; KRUEGER, LAURA; HAYES, ERICA K.; WILLIAMS, ASHLEY M.; ZALDIVAR, YAMITZEL; BENNETT, STEPHEN; CUMMINGS, ROBERT; TILZER, ART; VELTEN, ROBERT K.; KERR, NELSON; DASCH, GREGORY A.; HU, RENJIE

2018-01-01

Results of an environmental assessment conducted in a newly emergent focus of murine typhus in southern California are described. Opossums, Didelphis virginiana Kerr, infested with cat fleas, Ctenocephalides felis Buché, in the suburban area were abundant. Animal and flea specimens were tested for the DNA of two flea-borne rickettsiae, Rickettsia typhi and Rickettsia felis. R. felis was commonly detected in fleas collected throughout this area while R. typhi was found at a much lower prevalence in the vicinity of just 7 of 14 case-patient homes identified. DNA of R. felis, but not R. typhi, was detected in renal, hepatic, and pulmonary tissues of opossums. In contrast, there were no hematologic polymerase chain reaction findings of R. felis or R. typhi in opossums, rats, and cats within the endemic area studied. Our data suggest a significant probability of human exposure to R. felis in the area studied; however, disease caused by this agent is not recognized by the medical community and may be misdiagnosed as murine typhus using nondiscriminatory serologic methods. PMID:23270180

A LysR-Type Transcriptional Regulator, RovM, Senses Nutritional Cues Suggesting that It Is Involved in Metabolic Adaptation of Yersinia pestis to the Flea Gut.

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Viveka Vadyvaloo

Full Text Available Yersinia pestis has evolved as a clonal variant of Yersinia pseudotuberculosis to cause flea-borne biofilm-mediated transmission of the bubonic plague. The LysR-type transcriptional regulator, RovM, is highly induced only during Y. pestis infection of the flea host. RovM homologs in other pathogens regulate biofilm formation, nutrient sensing, and virulence; including in Y. pseudotuberculosis, where RovM represses the major virulence factor, RovA. Here the role that RovM plays during flea infection was investigated using a Y. pestis KIM6+ strain deleted of rovM, ΔrovM. The ΔrovM mutant strain was not affected in characteristic biofilm gut blockage, growth, or survival during single infection of fleas. Nonetheless, during a co-infection of fleas, the ΔrovM mutant exhibited a significant competitive fitness defect relative to the wild type strain. This competitive fitness defect was restored as a fitness advantage relative to the wild type in a ΔrovM mutant complemented in trans to over-express rovM. Consistent with this, Y. pestis strains, producing elevated transcriptional levels of rovM, displayed higher growth rates, and differential ability to form biofilm in response to specific nutrients in comparison to the wild type. In addition, we demonstrated that rovA was not repressed by RovM in fleas, but that elevated transcriptional levels of rovM in vitro correlated with repression of rovA under specific nutritional conditions. Collectively, these findings suggest that RovM likely senses specific nutrient cues in the flea gut environment, and accordingly directs metabolic adaptation to enhance flea gut colonization by Y. pestis.

Absence of zoonotic Bartonella species in questing ticks: First detection of Bartonella clarridgeiae and Rickettsia felis in cat fleas in the Netherlands

NARCIS (Netherlands)

Tijsse-Klasen, E.; Fonville, M.; Gassner, F.; Nijhof, A.M.; Hovius, E.K.E.; Jongejan, F.; Takken, W.; Reimerink, J.R.; Overgaauw, P.A.M.; Sprong, H.

2011-01-01

Background: Awareness for flea-and tick-borne infections has grown in recent years and the range of microorganisms associated with these ectoparasites is rising. Bartonella henselae, the causative agent of Cat Scratch Disease, and other Bartonella species have been reported in fleas and ticks. The

Absence of zoonotic Bartonella species in questing ticks: First detection of Bartonella clarridgeiae and Rickettsia felis in cat fleas in the Netherlands

NARCIS (Netherlands)

Tijsse-Klasen, E.; Fonville, M.; Gassner, F.; Nijhof, A.M.; Hovius, E.K.; Jongejan, F.; Takken, F.; Reimerink, J.R.; Overgaauw, P.A.M.; Sprong, H.

2011-01-01

BACKGROUND: Awareness for flea- and tick-borne infections has grown in recent years and the range of microorganisms associated with these ectoparasites is rising. Bartonella henselae, the causative agent of Cat Scratch Disease, and other Bartonella species have been reported in fleas and ticks. The

Preventive efficacy of Frontline® Combo and Certifect® against Dipylidium caninum infestation of cats and dogs using a natural flea (Ctenocephalides felis infestation model

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Beugnet Frederic

2013-01-01

Full Text Available Two studies were performed to evaluate the effectiveness of two monthly topical anti-flea products for the prevention of Dipylidium caninum infestations in cats and dogs. A single treatment with Frontline® Combo spot-on for cats (fipronil-(S-methoprene and two successive monthly treatments of Certifect® for dogs (fipronil-amitraz-(S-methoprene were assessed for the prevention of D. caninum infestations following weekly challenges of treated cats or dogs with metacestode naturally-infected fleas. The rate of infestations using the model in cats versus dogs explains the choice of a 1-month trial in cats and a 2-month trial in dogs. The experimental flea-infection model resulted in a range of 22–53% of the fleas being infected by Dipylidium cysticercoids. The arithmetic mean flea counts recorded for the untreated cats ranged from 51.2 to 68. The geometric mean flea counts recorded for the Frontline Combo treated cats differed significantly (p < 0.05 from those of the untreated control cats on all assessment days. The arithmetic mean flea counts recorded for the untreated dogs ranged from 166.6 to 238.6. The geometric mean flea counts recorded for the Certifect treated dogs differed significantly (p < 0.001 from those of the untreated group on all assessment days. Frontline Combo treatment on cats provided ≥99.8% persistent anti-flea efficacy throughout the 30-day treatment period. In the dog study, the two Certifect treatments provided ≥97% persistent efficacy throughout the 60-day study. Based on the collection of expelled D. caninum proglottids by cats, 100% (6/6 of the control cats and 0% (0/6 of Frontline Combo treated cats were infested with D. caninum. Frontline Combo spot-on for cats was therefore 100% effective in preventing infection with D. caninum. In dogs, 7 out of the 8 control group dogs (87.5% produced proglottids following infestation of infected fleas, whereas 0 out of 8 dogs (0% in the treated group were infected. The

Laboratory and field tests of Carbaryl 5% against fleas in Lushoto ...

African Journals Online (AJOL)

Background and Objective: Lushoto district in north-eastern Tanzania has been an active focus of plague disease since 1980 and many pesticides were used to control rodents and fleas from 1980 to 2003 when outbreaks occurred yearly. For over seven years ago commercial Carbaryl 5% powder has been used for ...

Knock-down and speed of kill of a combination of fipronil and permethrin for the prevention of Ctenocephalides felis flea infestation in dogs.

Science.gov (United States)

Halos, Lénaïg; Fourie, Josephus J; Fankhauser, Becky; Beugnet, Frederic

2016-02-02

A topical combination of fipronil + permethrin (Frontline Tri-Act/Frontect, Merial) has recently been developed to control fleas, ticks, mosquitoes, sandflies and stable flies on dogs. Two studies were conducted to assess its speed of kill and knock-down effect on Ctenocephalides felis fleas. The combination was compared to either fipronil alone or to a combination of permethrin, dinotefuran, and pyriproxyfen, In each study, 18 dogs were randomly allocated to one of three groups: (Group 1: untreated dog; Group 2: treated once on D0 with the combination of fipronil and permethrin; Group 3: treated once on D0 either with fipronil alone (study 1) or with a combination of permethrin, dinetofuran and pyriproxyfen (study 2)). Each dog was infested with 100 unfed adult C. felis fleas on Days 2 (study 2), 7, 14, 21 and 28. Fleas were collected from dogs at 1 h and 12 h post- infestations (PI) (study 1) or at 2 h and 6 h PI (study 2) to assess efficacy and from collection pans underneath cages 1 h (study 1) or 5 min (study 2) PI to assess knock-down effect. All treated dogs had significantly (p ≤ 0.01) lower flea counts than untreated dogs at every time point in both studies. For a whole month, a significant knock-down effect against infesting fleas is obtained in five minutes PI with the combination of permethrin and fipronil. Complete efficacy (>95%) was achieved in 1 h (study 1) or 2 h (study 2) PI for 14 days and by 6 h PI for all challenges conducted throughout the month. Efficacy remains >85% at 2 h PI for the whole month. A significantly higher efficacy of the fipronil + permethrin combination compared to other treatments was demonstrated at the earliest time points for the month (1 h knock-down effect and insecticidal efficacy compared to fipronil alone; 5 min knock-down effect compared to the combination of permethrin + dinetofuran + pyriproxyfen). The rapid flea knock-down effect and speed of kill demonstrated by the spot on combination of

Dipylidium caninum infection in dogs infested with fleas.

Science.gov (United States)

Wani, Z A; Allaie, I M; Shah, B M; Raies, A; Athar, H; Junaid, S

2015-03-01

The present study pertains to the Dipylidium caninum infection in dogs infested with fleas. Twenty dogs were presented to the Divison of Surgery, SKUAST-K for different surgical procedures. Majority of the dogs had a history of pruritus, loss of weight as well as rubbing their perineal region against the wall. On external examination dogs were found infested with Ctenocephalides canis. When dogs were anesthetized, motile segments were seen coming out of their anus, which were then identified as mature segments of D. caninum.

Efficacy of fipronil, amitraz and (S)-methoprene combination spot-on for dogs against adult dog fleas (Ctenocephalides canis, Curtis, 1826).

Science.gov (United States)

Bouhsira, Emilie; Yoon, Stephen S; Roques, Martine; Manavella, Coralie; Vermot, Solange; Cramer, Luiz G; Ollagnier, Catherine; Franc, Michel

2011-07-15

A novel spot-on formulation combining fipronil, amitraz and (S)-methoprene (CERTIFECT™, Merial Limited, GA, USA) was evaluated in adult Beagle dogs in a study to determine its adulticidal efficacy against the dog flea (Ctenocephalides canis, Curtis, 1826). Sixteen dogs were randomly allocated to treatment groups: 8 dogs served as untreated controls, and 8 dogs were treated once. Treatment consisted of applying a new combination formulation to deliver at least 6.7mg fipronil/kg body weight (bw), 8.0mg amitraz/kg bw, and 6.0mg (S)-methoprene/kg bw. The combination was designed to enhance the efficacy against ticks of the original fipronil/(S)-methoprene combination. Each dog was infested with 100 adult unfed dog fleas within 24h prior to treatment and then at weekly intervals for 8 weeks after treatment. At 24h after treatment or after each subsequent infestation, each dog was combed thoroughly to remove live fleas to be counted. A single treatment with CERTIFECT provided excellent knock-down of fleas within 24h after treatment and controlled re-infestations for up to 7 weeks (efficacy ≥96.5%, p<0.05). Copyright © 2011 Elsevier B.V. All rights reserved.

Flea abundance, diversity, and plague in Gunnison's prairie dogs (Cynomys gunnisoni) and their burrows in montane grasslands in northern New Mexico

Science.gov (United States)

Megan M. Friggens; Robert R. Parmenter; Michael Boyden; Paulette L. Ford; Kenneth Gage; Paul Keim

2010-01-01

Plague, a flea-transmitted infectious disease caused by the bacterium Yersinia pestis, is a primary threat to the persistence of prairie dog populations (Cynomys spp.). We conducted a 3-yr survey (2004-2006) of fleas from Gunnison's prairie dogs (Cynomys gunnisoni) and their burrows in montane grasslands in Valles Caldera National Preserve in New Mexico. Our...

Tick-, Flea-, and Louse-Borne Diseases of Public Health and Veterinary Significance in Nigeria

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Oluwaseun Oguntomole

2018-01-01

Full Text Available Mosquito-borne diseases are common high-impact diseases in tropical and subtropical areas. However, other non-mosquito vector-borne pathogens (VBPs may share their geographic distribution, seasonality, and clinical manifestations, thereby contributing their share to the morbidity and mortality caused by febrile illnesses in these regions. The purpose of this work was to collect and review existing information and identify knowledge gaps about tick, flea-, and louse-borne diseases of veterinary and public health significance in Nigeria. Full-length articles about VBPs were reviewed and relevant information about the vectors, their hosts, geographic distribution, seasonality, and association(s with human or veterinary diseases was extracted. Specific laboratory tools used for detection and identification of VBPs in Nigeria were also identified. A total of 62 original publications were examined. Substantial information about the prevalence and impacts of ticks and fleas on pet and service dogs (18 articles, and livestock animals (23 articles were available; however, information about their association with and potential for causing human illnesses was largely absent despite the zoonotic nature of many of these peri-domestic veterinary diseases. Recent publications that employed molecular methods of detection demonstrated the occurrence of several classic (Ehrlichia canis, Rickettsia africae, Bartonella sp. and emerging human pathogens (R. aeschlimannii, Neoehrlichia mikurensis in ticks and fleas. However, information about other pathogens often found in association with ticks (R. conorii and fleas (R. typhi, R. felis across the African continent was lacking. Records of louse-borne epidemic typhus in Nigeria date to 1947; however, its current status is not known. This review provides an essential baseline summary of the current knowledge in Nigeria of non-mosquito VBPs, and should stimulate improvements in the surveillance of the veterinary and

Preventive efficacy of Frontline® Combo and Certifect® against Dipylidium caninum infestation of cats and dogs using a natural flea (Ctenocephalides felis) infestation model.

Science.gov (United States)

Beugnet, Frederic; Delport, Peet; Luus, Hermann; Crafford, Dione; Fourie, Josephus

2013-01-01

Two studies were performed to evaluate the effectiveness of two monthly topical anti-flea products for the prevention of Dipylidium caninum infestations in cats and dogs. A single treatment with Frontline(®) Combo spot-on for cats (fipronil-(S)-methoprene) and two successive monthly treatments of Certifect(®) for dogs (fipronil-amitraz-(S)-methoprene) were assessed for the prevention of D. caninum infestations following weekly challenges of treated cats or dogs with metacestode naturally-infected fleas. The rate of infestations using the model in cats versus dogs explains the choice of a 1-month trial in cats and a 2-month trial in dogs. The experimental flea-infection model resulted in a range of 22-53% of the fleas being infected by Dipylidium cysticercoids. The arithmetic mean flea counts recorded for the untreated cats ranged from 51.2 to 68. The geometric mean flea counts recorded for the Frontline Combo treated cats differed significantly (p caninum proglottids by cats, 100% (6/6) of the control cats and 0% (0/6) of Frontline Combo treated cats were infested with D. caninum. Frontline Combo spot-on for cats was therefore 100% effective in preventing infection with D. caninum. In dogs, 7 out of the 8 control group dogs (87.5%) produced proglottids following infestation of infected fleas, whereas 0 out of 8 dogs (0%) in the treated group were infected. The infection rates of the two groups were significantly different. The percent effectiveness for the Certifect treatment group for the prevention of D. caninum infection was 100% during this 2-month trial. No treatment-related adverse events were observed in either cats or dogs during these studies. © F. Beugnet et al., Published by EDP Sciences 2013.

SEASON OF DELTAMETHRIN APPLICATION AFFECTS FLEA AND PLAGUE CONTROL IN WHITE-TAILED PRAIRIE DOG (CYNOMYS LEUCURUS) COLONIES, COLORADO, USA.

Science.gov (United States)

Tripp, Daniel W; Streich, Sean P; Sack, Danielle A; Martin, Daniel J; Griffin, Karen A; Miller, Michael W

2016-07-01

In 2008 and 2009, we evaluated the duration of prophylactic deltamethrin treatments in white-tailed prairie dog ( Cynomys leucurus ) colonies and compared effects of autumn or spring dust application in suppressing flea numbers and plague. Plague occurred before and during our experiment. Overall, flea abundance tended to increase from May or June to September, but it was affected by deltamethrin treatment and plague dynamics. Success in trapping prairie dogs (animals caught/trap days) declined between June and September at all study sites. However, by September trap success on dusted sites (19%; 95% confidence interval [CI] 16-22%) was about 15-fold greater than on undusted control sites (1%; CI 0.3-4%; P≤0.0001). Applying deltamethrin dust as early as 12 mo prior seemed to afford some protection to prairie dogs. Our data showed that dusting even a portion of a prairie dog colony can prolong its persistence despite epizootic plague. Autumn dusting may offer advantages over spring in suppressing overwinter or early-spring flea activity, but timing should be adjusted to precede the annual decline in aboveground activity for hibernating prairie dog species. Large colony complexes or collections of occupied but fragmented habitat may benefit from dusting some sites in spring and others in autumn to maximize flea suppression in a portion of the complex or habitat year-round.

Efficacy of imidacloprid + moxidectin and selamectin topical solutions against the KS1 Ctenocephalides felis flea strain infesting cats

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Dryden Michael W

2011-09-01

Full Text Available Abstract Background Two studies were conducted to evaluate and compare the efficacy of imidacloprid + moxidectin and selamectin topical solutions against the KS1 flea strain infesting cats. In both studies the treatment groups were comprised of non-treated controls, 6% w/v selamectin (Revolution®; Pfizer Animal Health topical solution and 10% w/v imidacloprid + 1% w/v moxidectin (Advantage Multi® for Cats, Bayer Animal Health topical solution. All cats were infested with 100 fleas on Days -2, 7, 14, 21, and 28. The difference in the studies was that in study #1 efficacy evaluations were conducted at 24 and 48 hours post-treatment or post-infestation, and in study #2 evaluations were conducted at 12 and 24 hours. Results In study #1 imidacloprid + moxidectin and the selamectin formulation provided 99.8% and 99.0% efficacy at 24 hours post-treatment. On day 28, the 24 hour efficacy of the selamectin formulation dropped to 87.1%, whereas the imidacloprid + moxidectin formulation provided 98.9% efficacy. At the 48 hour assessments following the 28 day infestations, efficacy of the imidacloprid + moxidectin and selamectin formulations was 96.8% and 98.3% respectively. In study # 2 the efficacy of the imidacloprid + moxidectin and selamectin formulations 12 hours after treatment was 100% and 69.4%, respectively. On day 28, efficacy of the imidacloprid + moxidectin and selamectin formulations 12 hours after infestation was 90.2% and 57.3%, respectively. In study #2 both formulations provided high levels of efficacy at the 24 hour post-infestation assessments, with selamectin and imidacloprid + moxidectin providing 95.3% and 97.5% efficacy, following infestations on day 28. Conclusions At the 24 and 48 hour residual efficacy assessments, the imidacloprid + moxidectin and selamectin formulations were similarly highly efficacious. However, the imidacloprid + moxidectin formulation provided a significantly higher rate of flea kill against the KS1 flea

Silencing urease: A key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route

Science.gov (United States)

Chouikha, Iman; Hinnebusch, B. Joseph

2014-01-01

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30–40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential. PMID:25453069

Silencing urease: a key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route.

Science.gov (United States)

Chouikha, Iman; Hinnebusch, B Joseph

2014-12-30

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30-40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential.

Toxicity and transfer of polyvinylpyrrolidone-coated silver nanowires in an aquatic food chain consisting of algae, water fleas, and zebrafish

Energy Technology Data Exchange (ETDEWEB)

Chae, Yooeun; An, Youn-Joo, E-mail: anyjoo@konkuk.ac.kr

2016-04-15

Highlights: • Trophic transfer of silver nanowires (AgNWs) was studied in an aquatic food chain. • The transfer of AgNWs from algae to fish via water fleas was observed. • Toxicity of long AgNWs on aquatic organisms is higher than that of short ones. • AgNWs damage the gut of water fleas and may cause undernourishment. • Quantity of lipid droplets increased with increasing exposure concentration. - Abstract: Nanomaterials of various shapes and dimensions are widely used in the medical, chemical, and electronic industries. Multiple studies have reported the ecotoxicological effects of nanaoparticles when released in aquatic and terrestrial ecosystems; however, information on the toxicity of silver nanowires (AgNWs) to freshwater organisms and their transfer through the food webs is limited. In the present study, we aimed to evaluate the toxicity of 10- and 20-μm-long AgNWs to the alga Chlamydomonas reinhardtii, the water flea Daphnia magna, and the zebrafish and study their movement through this three-species food chain using a variety of qualitative and quantitative methods as well as optical techniques. We found that AgNWs directly inhibited the growth of algae and destroyed the digestive organs of water fleas. The results showed that longer AgNWs (20 μm) were more toxic than shorter ones (10 μm) to both algae and water fleas, but shorter AgNWs were accumulated more than longer ones in the body of the fish. Overall, this study suggests that AgNWs are transferred through food chains, and that they affect organisms at higher trophic levels, potentially including humans. Therefore, further studies that take into account environmental factors, food web complexity, and differences between nanomaterials are required to gain better understanding of the impact of nanomaterials on natural communities and human health.

Toxicity and transfer of polyvinylpyrrolidone-coated silver nanowires in an aquatic food chain consisting of algae, water fleas, and zebrafish

International Nuclear Information System (INIS)

Chae, Yooeun; An, Youn-Joo

2016-01-01

Highlights: • Trophic transfer of silver nanowires (AgNWs) was studied in an aquatic food chain. • The transfer of AgNWs from algae to fish via water fleas was observed. • Toxicity of long AgNWs on aquatic organisms is higher than that of short ones. • AgNWs damage the gut of water fleas and may cause undernourishment. • Quantity of lipid droplets increased with increasing exposure concentration. - Abstract: Nanomaterials of various shapes and dimensions are widely used in the medical, chemical, and electronic industries. Multiple studies have reported the ecotoxicological effects of nanaoparticles when released in aquatic and terrestrial ecosystems; however, information on the toxicity of silver nanowires (AgNWs) to freshwater organisms and their transfer through the food webs is limited. In the present study, we aimed to evaluate the toxicity of 10- and 20-μm-long AgNWs to the alga Chlamydomonas reinhardtii, the water flea Daphnia magna, and the zebrafish and study their movement through this three-species food chain using a variety of qualitative and quantitative methods as well as optical techniques. We found that AgNWs directly inhibited the growth of algae and destroyed the digestive organs of water fleas. The results showed that longer AgNWs (20 μm) were more toxic than shorter ones (10 μm) to both algae and water fleas, but shorter AgNWs were accumulated more than longer ones in the body of the fish. Overall, this study suggests that AgNWs are transferred through food chains, and that they affect organisms at higher trophic levels, potentially including humans. Therefore, further studies that take into account environmental factors, food web complexity, and differences between nanomaterials are required to gain better understanding of the impact of nanomaterials on natural communities and human health.

Flea Bite Dermatitis in a Herd of Dairy Calves in Vom Nigeria ...

African Journals Online (AJOL)

They have piercing and sucking mouth parts which are specially designed for injecting into a host and sucking blood. They feed on the blood of cats, dogs and other animals, including humans (Lyon, 1997; Kramer and Mencke, 2001). Flea infestation in cattle and other ruminants is rare; it has been more commonly reported ...

Contribution of land use to rodent flea load distribution in the plague ...

African Journals Online (AJOL)

These findings suggest that land use factors have a major influence on rodent flea abundance which can be taken as a proxy for plague infection risk. The results further point to the need for a comprehensive package that includes land tillage and crop type considerations on one hand and the associated human activities on ...

Flea (Ctenocephalides felis) control efficacy of topical indoxacarb on dogs subsequently bathed with a chlorhexidine–ketoconazole shampoo

Science.gov (United States)

Liebenberg, JE; Heaney, K; Guerino, F

2015-01-01

Objective An evaluation of the effect of chlorhexidine/ketoconazole shampoo baths on the flea control efficacy of indoxacarb applied topically to dogs. Methods and Results We randomly allocated 18 healthy mixed‐breed dogs to 3 groups: shampoo only; indoxacarb treated and medicated shampoo; and indoxacarb treated but not shampooed. Indoxacarb was administered on day 0 and dogs were shampooed on days 9 and 23. Dogs were infested with 100 adult Ctenocephalides felis initially 2 days before treatment and then weekly from days 7 to 28. Fleas were removed and counted 48 h post‐infestation. Conclusion Medicated shampoo use did not significantly reduce indoxacarb efficacy against C. felis. PMID:26220323

Assessing plague risk and presence through surveys of small mammal flea communities

Science.gov (United States)

M. M. Friggens; P. L. Ford; R. R. Parmenter; M. Boyden; K. Gage

2011-01-01

Plague, caused by the bacterium Yersinia pestis, remains a threat to human and wildlife populations in the Western United States (Gage and Kosoy 2005). Several rodent species have been implicated as important maintenance hosts in the U.S., including Peromyscus maniculatus and Dipodomys spp. Fleas are a critical component of plague foci (Gage and Kosoy 2005)....

Evaluation and comparison of a flumethrin-imidacloprid collar and repeated monthly treatments of fipronil/(s)-methoprene to control flea, Ctenocephalides f. felis, infestations on cats for eight months.

Science.gov (United States)

Dryden, Michael W; Smith, Vicki; Davis, Wendell L; Settje, Terry; Hostetler, Joe

2016-05-17

This controlled laboratory study was designed to evaluate the efficacy of the 10 % imidacloprid/4.5 % flumethrin collar (Seresto®, Bayer Animal Health) against fleas (Ctenocephalides f. felis) on cats, when compared to fipronil (9.8 %w/w)/(s)-methoprene (11.8 % w/w) topical spot-on formulation (Frontline® Plus for Cats and Kittens, Merial). Thirty cats were randomized into three groups of ten animals based on pre-treatment flea counts: Group 1: imidacloprid/flumethrin collar; Group 2: fipronil/(s)-methoprene topical spot-on and Group 3: non-treated controls. The imidacloprid/flumethrin collars were applied one time on Day 0, while the fipronil/(s)-methoprene spot-on was administered every 30 days from Day 0 through Day 210. Cats were infested with 100 fleas on study days 0, 7, 14, 29, 59, 89, 119, 149, 179, 209 and 239. All flea counts were conducted by combing to remove fleas on post-treatment days 2, 8, 15, 30, 60, 90, 120, 150, 180, 210 and 240. The efficacy of the imidacloprid/flumethrin collar ranged from 98.2 to 100 % for eight months. The efficacy of fipronil/(s)-methoprene spot-on ranged from 68.2 to 99.9 %. Efficacy was imidacloprid/flumethrin collar group when compared to the fipronil/(s)-methoprene group on Days 90, 150 and 210 (P imidacloprid/flumethrin collar (Seresto®, Bayer Animal Health) maintained excellent ( > 98.2 %) efficacy against fleas on cats for the entire 8 month study. Monthly applications of fipronil/(s)-methoprene (Frontline® Plus for Cats and Kittens, Merial) generally had high, but variable (68.2 to 99.9 %) efficacy over the course of the eight month study. Based on the very high residual efficacy achieved by the imidacloprid/flumethrin collar in this study, veterinarians should expect that this collar will control and eliminate existing flea infestations on cats and in their in-home premises as long as every flea infested host is treated.

Evaluation of the effectiveness of a novel oral formulation of sarolaner (Simparica™) for the treatment and control of fleas on dogs.

Science.gov (United States)

Six, Robert H; Geurden, Thomas; Packianathan, Raj; Colgan, Sally; Everett, William R; Grace, Sarah; Hodge, Andrew; Mahabir, Sean P; Myers, Melanie R; Slootmans, Nathalie; Davis, Kylie

2016-05-30

The efficacy of a single oral dose of a novel isoxazoline, sarolaner (Simparica™, Zoetis), for the treatment and control of flea infestations on dogs was confirmed in five laboratory studies. The studies were conducted using adult purpose-bred Beagles and/or mixed breed dogs. All animals were individually identified and housed, and were allocated randomly to treatment with either placebo or sarolaner (eight to 10 per group) based on pretreatment parasite counts. Three studies used cat flea (Ctenocephalides felis felis) strains recently isolated from the field from the US, EU, or Australia; in the fourth study a laboratory strain (KS1) with documented tolerance to a number of insecticides such as fipronil, imidacloprid, and permethrin was used. In the fifth study, dogs were infested with dog fleas, Ctenocephalides canis. Dogs were treated orally on Day 0 with a placebo or a sarolaner tablet providing a minimum dose of 2mg/kg. Dogs were infested with approximately 100 unfed, adult fleas prior to treatment and at weekly intervals post-treatment. Comb counts were conducted to determine the numbers of viable fleas at 24h after treatment and after each subsequent infestation. Efficacy against C. felis and C. canis was 99.8-100% from treatment through Day 35. In all five studies, elimination of existing infestations was achieved within 24h after dosing, with only a single live C. felis found on one dog on Day 1. Similarly, control of flea challenges was achieved within 24h after infestation throughout the 35day study periods, with only single live C. felis found on two dogs on Day 28 in one study, and on a single dog on Day 35 in another study. There were no adverse reactions to treatment with sarolaner. These studies confirmed that a single oral dose of sarolaner at 2mg/kg provided highly effective treatment of existing C. felis infestations and persistent control of C. felis on dogs for 35days after treatment. Efficacy equivalent to that seen with C. felis was

Differential control of Yersinia pestis biofilm formation in vitro and in the flea vector by two c-di-GMP diguanylate cyclases.

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Yi-Cheng Sun

2011-04-01

Full Text Available Yersinia pestis forms a biofilm in the foregut of its flea vector that promotes transmission by flea bite. As in many bacteria, biofilm formation in Y. pestis is controlled by intracellular levels of the bacterial second messenger c-di-GMP. Two Y. pestis diguanylate cyclase (DGC enzymes, encoded by hmsT and y3730, and one phosphodiesterase (PDE, encoded by hmsP, have been shown to control biofilm production in vitro via their opposing c-di-GMP synthesis and degradation activities, respectively. In this study, we provide further evidence that hmsT, hmsP, and y3730 are the only three genes involved in c-di-GMP metabolism in Y. pestis and evaluated the two DGCs for their comparative roles in biofilm formation in vitro and in the flea vector. As with HmsT, the DGC activity of Y3730 depended on a catalytic GGDEF domain, but the relative contribution of the two enzymes to the biofilm phenotype was influenced strongly by the environmental niche. Deletion of y3730 had a very minor effect on in vitro biofilm formation, but resulted in greatly reduced biofilm formation in the flea. In contrast, the predominant effect of hmsT was on in vitro biofilm formation. DGC activity was also required for the Hms-independent autoaggregation phenotype of Y. pestis, but was not required for virulence in a mouse model of bubonic plague. Our results confirm that only one PDE (HmsP and two DGCs (HmsT and Y3730 control c-di-GMP levels in Y. pestis, indicate that hmsT and y3730 are regulated post-transcriptionally to differentially control biofilm formation in vitro and in the flea vector, and identify a second c-di-GMP-regulated phenotype in Y. pestis.

Myxomatosis: passive immunity in the offspring of immune rabbits (Oryctolagus cuniculus) infested with fleas (Spilopsyllus cuniculi Dale) and exposed to myxoma virus.

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Sobey, W R; Conolly, D

1975-02-01

Kittens with maternal antibodies to myxoma virus, the offspring of rabbits which had recovered from myxomatosis, were exposed to fleas contaminated with myxoma virus and/or contact with infected rabbits from birth. All kittens died or became infected before 8 weeks of age. When compared with adult animals similarly infected the kittens showed no advantage in terms of survival time or recovery rate attributable to maternal antibodies. Flea transmission of virus was found more effective than contact transmissions.

Survival of cabbage stem flea beetle larvae, Psylliodes chrysocephala, exposed to low temperatures

DEFF Research Database (Denmark)

Mathiasen, Helle; Bligaard, J.; Esbjerg, Peter

2015-01-01

The cabbage stem flea beetle, Psylliodes chrysocephala (L.) (Coleoptera: Chrysomelidae), is a major pest of winter oilseed rape. The larvae live throughout winter in leaf petioles and stems. Winter temperatures might play an important role in survival during winter and hence population dynamics, ...

Flea (Ctenocephalides felis) control efficacy of topical indoxacarb on dogs subsequently bathed with a chlorhexidine-ketoconazole shampoo.

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Armstrong, R D; Liebenberg, J E; Heaney, K; Guerino, F

2015-08-01

An evaluation of the effect of chlorhexidine/ketoconazole shampoo baths on the flea control efficacy of indoxacarb applied topically to dogs. We randomly allocated 18 healthy mixed-breed dogs to 3 groups: shampoo only; indoxacarb treated and medicated shampoo; and indoxacarb treated but not shampooed. Indoxacarb was administered on day 0 and dogs were shampooed on days 9 and 23. Dogs were infested with 100 adult Ctenocephalides felis initially 2 days before treatment and then weekly from days 7 to 28. Fleas were removed and counted 48 h post-infestation. Medicated shampoo use did not significantly reduce indoxacarb efficacy against C. felis. © 2015 MSD Animal Health. Australian Veterinary Journal published by Wiley Publishing Asia Pty Ltd on behalf of Australian Veterinary Association.

[Cockroaches and co. The role of health pests as allergen source].

Science.gov (United States)

Raulf, M; Sander, I; Gonnissen, D; Zahradnik, E; Brüning, T

2014-05-01

In most of the cases health pests are carriers of pathogens or parasites which have a negative impact on human health or affect the health of other mammals. What is lesser known is that they can also act as allergens. Most of the health pests in this sense belong to the arthropods, such as cockroaches (Blattaria), mosquitos (Culiciformia), lice (Pediculus humanus corporis), fleas (Siphonaptera) and ticks (Argasidae). In the group of vertebrates rats (Rattus norvegicus and Rattus rattus), house mice (Mus musculus) and pigeons (Columba livia domestica) are also classified as health pests. Also storage pests which are not carriers of pathogens can induce secondary infestation with hygiene pests or molds and have an underestimated impact on human health. In this article selected examples of health pests and also storage pests as an allergen source are described, taking into account the sensitization prevalence and identified single allergens.

Effects of parasitism on host reproductive investment in a rodent-flea system: host litter size matters.

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Warburton, Elizabeth M; Khokhlova, Irina S; Dlugosz, Elizabeth M; Der Mescht, Luther Van; Krasnov, Boris R

2017-02-01

Parents may alter offspring phenotype depending on the type of environment they encounter. Parasitism is a common stressor; therefore, maternal reproductive investment could change in response to parasitic infection. However, few experiments have investigated the relationship between parasitism and maternal investment, whereas earlier field studies provided contradictory evidence. We investigated number, sex ratio, and growth of offspring in two rodent species, solitary altricial Meriones crassus and social precocial Acomys cahirinus, exposed to parasitism by fleas Xenopsylla ramesis and Parapulex chephrenis. No effect of treatment on litter size or sex ratio of a litter was found in either rodent species. Flea parasitism was found to affect pre-weaning body mass gain in M. crassus, but not in A. cahirinus pups. Furthermore, it appeared that female M. crassus invested resources into their offspring differently in dependence of litter size. In small litters (1-3 offspring), pups from infested females gained more body mass before weaning than pups from uninfested mothers. However, this trend was reversed in females with large litters indicating that parasitized females have a finite amount of resources with which to provision their young. Thus, M. crassus mothers parasitized by fleas seemed to receive some sort of external cues (e.g., stress caused by infestation) that prompted them to alter offspring provisioning, depending on species-specific possibilities and constraints. Therefore, parasites could be a mediator of environmentally induced maternal effects and offspring provisioning may have adaptive value against parasitism.

Effect of temperature and relative humidity on the development times and survival of Synopsyllus fonquerniei and Xenopsylla cheopis, the flea vectors of plague in Madagascar.

Science.gov (United States)

Kreppel, Katharina S; Telfer, Sandra; Rajerison, Minoarisoa; Morse, Andy; Baylis, Matthew

2016-02-11

Plague, a zoonosis caused by Yersinia pestis, is found in Asia, the Americas but mainly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. In the highlands of Madagascar, plague is transmitted predominantly by two flea species which coexist on the island, but differ in their distribution. The endemic flea, Synopsyllus fonquerniei, dominates flea communities on rats caught outdoors, while the cosmopolitan flea, Xenopsylla cheopis, is found mostly on rats caught in houses. Additionally S. fonquerniei seems restricted to areas above 800 m. Climatic constraints on the development of the two main vectors of plague could explain the differences in their distribution and the seasonal changes in their abundance. Here we present the first study on effects of temperature and relative humidity on the immature stages of both vector species. We examined the two species' temperature and humidity requirements under experimental conditions at five different temperatures and two relative humidities. By employing multivariate and survival analysis we established the impact of temperature and relative humidity on development times and survival for both species. Using degree-day analysis we then predicted the average developmental threshold for larvae to reach pupation and for pupae to complete development under each treatment. This analysis was undertaken separately for the two relative humidities and for the two species. Development times and time to death differed significantly, with the endemic S. fonquerniei taking on average 1.79 times longer to complete development and having a shorter time to death than X. cheopis under adverse conditions with high temperature and low humidity. Temperature had a significant effect on the development times of flea larvae and pupae. While humidity did not affect the development times of either species, it did influence the time of death of S. fonquerniei. Using degree-day analysis we estimated an

The chiggerflea Hectopsylla pulex (Siphonaptera: Tungidae as an ectoparasite of free-tailed bats (Chiroptera: Molossidae

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Júlia Lins Luz

2009-07-01

Full Text Available In the present study, we investigated the prevalence and intensity of Hectopsylla pulex infection in Molossus rufus and Molossus molossus, the parasite's choice of attachment site, and whether this host-parasite system varies with host size. Twenty-four bats were captured by hand from the roof of a house in Southeastern Brazil. M. rufus exhibited a prevalence of 71.4% and the mean intensity averaged 5 ectoparasites per bat. M. molossus exhibited a prevalence of 90%, and the average mean intensity was 2.11 ectoparasites. The attachment sites were: ear, tragus, shoulder blade and tibia, anus, wing, axilla, mouth and dactylopatagium. A positive correlation was observed between the bats' weight and the number of fleas.

Tungiasis in Italy: An imported case of Tunga penetrans and review of the literature.

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Palicelli, Andrea; Boldorini, Renzo; Campisi, Paola; Disanto, Maria Giulia; Gatti, Lucio; Portigliotti, Luca; Tosoni, Antonella; Rivasi, Francesco

2016-05-01

Tungiasis is an animal and human parasitic disease caused by fleas of the genus Tunga (Siphonaptera, Tungidae), endemic in equatorial and subtropical regions and rarely described in European countries, where clinicians and general pathologists could be not aware of this parasitic disease. To our knowledge, only 75 cases of human tungiasis (not all described in detail) were previously reported in Italy. We described a new case in a 34-year-old Italian flight attendant who developed a granuloma-like, ulcerated nodule in the subungual region of his left 5th toe, partially detaching the nail, about 20-30 days after his return from Brazil. We performed a detailed review of the literature of the Italian cases, suggesting the use of histochemical stains (especially Trichrome stain) in order to underline parasitic details. Tourism in endemic regions and globalization may result in new cases in developed countries and previously unaffected regions, therefore pathologists should consider this parasitic disease. Copyright © 2016 Elsevier GmbH. All rights reserved.

[Present Status of Displaying Pharmaceutical Products for Sale on Flea Market Applications for Smartphones and the Responses to Illicit Selling by Service Providers].

Science.gov (United States)

Kishimoto, Keiko; Takeuchi, Tomoe; Fukushima, Noriko

2017-12-01

 In Japan, a pharmacy or drug store license is required for selling pharmaceutical products. However, civilians without a pharmacy or drug store license are displaying pharmaceutical products for sale on a flea market application, which is illegal dealing. This study discussed the modality for implementing countermeasures for the illicit selling of pharmaceutical products. We extracted pharmaceutical products displayed for sale on three flea market applications (Mercari, Rakuma, Fril) on one day. One hundred and eighty-one pharmaceutical products were displayed (49 on Mercari, 86 on Rakuma, and 46 on Fril). There were 6.1% (11/181) domestically prescribed drugs, 69.1% (125/181) domestic OTC drugs, 23.8% (43/181) foreign-made prescribed drugs, and 1.1% (2/181) foreign-made OTC drugs. The seller could display the product for sale without confirming whether it is prohibited. We alerted the service providers of this illicit selling at flea markets at three different instances. The pharmaceutical product displays were deleted by the service providers at a rate of 55.1% (27/49) for Mercari and 51.2% (44/86) for Rakuma. The average number of drugs that were displayed for sale by each seller was 1.4 and the average number of total products that were displayed for sale by each seller was 100. The seller could have unintentionally displayed the pharmaceutical products for sale, without the knowledge that it is illegal. The service providers of flea market applications should create mechanisms to alert the sellers that displaying pharmaceutical products for sale is an illicit act and regulate these violations.

Stevesaltica, a new genus of moss and leaf-litter inhabiting flea beetles from Bolivia (Coleoptera: Chrysomelidae: Galerucinae: Alticini)

Science.gov (United States)

A new genus (Stevesaltica) with two new species (S. normi and S. perdita) from Bolivia is described and illustrated. It is similar to Exoceras Jacoby. An identification key for all flea beetle genera known to occur in mosses in the Western Hemisphere is provided....

High prevalence of Rickettsia typhi and Bartonella species in rats and fleas, Kisangani, Democratic Republic of the Congo

NARCIS (Netherlands)

Laudisoit, A.; Falay, D.; Amundala, N.; de Bellock, J.G.; van Houtte, N.; Breno, M.; Verheven, E.; Wilschut, Liesbeth; Parola, P.; Raoult, D.; C., Socolovschi

2014-01-01

The prevalence and identity of Rickettsia and Bartonella in urban rat and flea populations were evaluated in Kisangani, Democratic Republic of the Congo (DRC) by molecular tools. An overall prevalence of 17% Bartonella species and 13% Rickettsia typhi, the agent of murine typhus, was found in the

Integrated control of ticks and fleas on dogs with particular reference to the prevention of vector-borne diseases

NARCIS (Netherlands)

Fourie, J.J.

2015-01-01

Because dogs are such loved companion animals, their health and wellbeing is of great importance to their human companions. Moreover, controlling ticks and fleas on dogs is also important in respect of the zoonotic risk that some of these parasites pose to their human companions. Numerous products

Effect of temperature on reproduction and embryonic development of the cabbage stem flea beetle, Psylliodes chrysocephala L., (Coleoptera: Chrysomelidae)

DEFF Research Database (Denmark)

Mathiasen, Helle; Sørensen, Helle; Bligaard, J.

2015-01-01

The cabbage stem flea beetle, Psylliodes chrysocephala (L.) (Coleoptera: Chrysomelidae), is a major pest of winter oilseed rape. Despite the importance of this pest, detailed information on reproduction to predict risk of crop damage is lacking. This study investigates the effect of temperature...

Efficacy of orally administered powdered aloe juice (Aloe ferox against ticks on cattle and ticks and fleas on dogs

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J.J. Fourie

2005-06-01

Full Text Available The efficacy of orally administered powdered aloe juice (Aloe ferox was evaluated against ticks on cattle and against ticks and fleas on dogs. Twelve calves were each infested over a 25-day period with approximately 4000 larvae of Rhipicephalus (Boophilus decoloratus and allocated to 3 groups of 4 calves each. Three days after the last larval infestation and daily for 22 days thereafter, the calves in 1 group were fed 5 mg / kg body weight and those in another 25 mg / kg body weight of powdered aloe juice incorporated in game maintenance pellets, while the animals in the 3rd group received only pellets. Detached female ticks were collected daily and counted and the weights and the fertility of groups of 50 engorged female ticks collected from the animals were ascertained. The powdered aloe juice in the game maintenance pellets had no effect on the tick burdens of the calves or on the fertility of the ticks. Six dogs, in each of 2 groups, were treated daily for 15 consecutive days, commencing on Day -5 before the 1st tick infestation, with either 0.39 g or 0.74 g of powdered aloe juice, administered orally in gelatin capsules, while a 3rd group of 6 dogs served as untreated controls. All the dogs were challenged with Haemaphysalis leachi on Days 0 and +7, and with Ctenocephalides felis on Days+1and +8, and efficacy assessments were made 1 day after flea and 2 days after tick challenge, respectively. Treatment was not effective against ticks or fleas on the dogs.

ECTOFAUNA PARASITÁRIA DE CÃES URBANOS DOMICILIADOS ATENDIDOS EM CLÍNICAS VETERINÁRIAS PARTICULARES NA CIDADE DE LAVRAS, MG

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Antonio Marcos Guimarães

2011-03-01

Full Text Available The objective of this study was to determine the frequency of ectoparasites in urban domiciled dogs treated at nine private veterinary clinics in the city of Lavras, Minas Gerais, Brazil. Visible and palpable ectoparasites specimens were collected manually from 67 dogs during the period of September 2004 to May 2005, kept in flasks with ethanol 70º GL and identified under a stereomicroscope. In the case of mites that cause mange, performed the analysis of the results obtained from 155 skin scrapings of the same number of dogs with clinical suspicion of parasitic dermatosis was performed, and sent to diagnostic at the Laboratory of Parasitic Diseases of Federal University of Lavras (UFLA, during the period of September 2002 to July 2007. A total of 540 ectoparasites were recorded, and four species were identified: Rhipicephalus sanguineus (60%, Ctenocephalides canis and C. felis (both 36%, and Dermatobia hominis larvae (4%. In scraped skin, positive results were verified in 12.9% (20/155, of which 80.0% with Demodex canis (16/20 and 20.0% with Sarcoptes scabiei var. canis (4/20. After ectoparasites identification a database with the dogs´medical records was made and analyzed by SPSS 12.0. It can be concluded that the predominant species of ectoparasites in dogs treated at private veterinary clinics in the city of Lavras, MG, were Ctenocephalides canis and C. felis (Siphonaptera: Pulicidae and R. sanguineus (Acari: Ixodidae and Demodex canis (Acari: Demodecidae that had a significant predominance (p<0.05 on scraped skin of young animals with suspicion of canine demodicosis.

Invertebrates of The H.J. Andrews Experimental Forest, Western Cascades, Oregon: I. An annotated checklist of fleas.

Science.gov (United States)

Robert E. Lewis; Chris Maser

1981-01-01

During a trapping survey of small mammals (approximately 3,000 individuals), species of fleas (1,632 specimens) were collected in the H.J. Andrews Experimental Forest, Western Cascades, Oregon. Host mammals were represented by 15 species—6 insectivores and 9 rodents captured from June through September. The collections extend our knowledge of the fauna of Oregon.

External parasites of raptors (Falconiformes and Strigiformes: identification in an ex situ population from Mexico

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JaquelineB de Oliveira

2011-09-01

Full Text Available Raptorial birds harbor a variety of ectoparasites and the mayority of them are host specific. The aim of this study was to identify the ectoparasites of captive birds of prey from Mexico, as well as to verify their impact in the health of infested birds. Raptorial birds were confiscated and kept in captivity at the Centro de Investigación y Conservación de Vida Silvestre (CIVS in Los Reyes La Paz, Mexico State. Seventy-four birds of prey (66 Falconiformes and eigth Strigiformes of 15 species were examined for the presence of ectoparasites. We examined both juvenile and adult birds from both sexes. The overall prevalence was 16.2%; 66.7% of raptors were infested with a single type of external parasite. Lice were the most prevalent ectoparasites (91.7%, followed by feather mites and fleas (8.3%. Degeeriella fulva (72.7%, Craspedorrhynchus sp. (45.4% and Strigiphilus aitkeni (9.1% (Ischnocera, Philopteridae were recovered from wings, head and neck regions of red-tailed hawk (Buteo jamaicensis, Swainson’s hawk (B. swainsoni, Harris’s hawk (Parabuteo unicinctus and Barn owl (Tyto alba. Low lice infestation level was observed. Nymphs and females of feather mites Kramerella sp. (Pterolichoidea, Kramerellidae were recovered solely from Barn owl (T. alba; while one Caracara (Caracara cheriway was infested by the sticktight flea Echidnophaga gallinacea (Siphonaptera, Pulicidae. No clinical signs were observed in any infested bird. Probably the periodic use of organophosphorates was responsible of the low prevalence and lice infestation levels. The diversity of external parasites illustrates the importance of detailed revision of incoming and long-term captive raptors as part of responsible captive management. Five new hosts and geographic records are presented. Rev. Biol. Trop. 59 (3: 1257-1264. Epub 2011 September 01.Las aves rapaces albergan una gran variedad de ectoparásitos y la mayoría de ellos son específicos de acogida. El objetivo de este

Primer registro de Dasypsyllus (Avesopsylla lasius lasius (Siphonaptera: Ceratophyllidae en nidos de golondrina chilena, Tachycineta meyeni (Passeriformes: Hirundinidae, en Ushuaia (Tierra del Fuego, Argentina First record of Dasypsyllus (Avesopsylla lasius lasius (Siphonaptera: Ceratophyllidae in Chilean swallow nests Tachycineta meyeni (Passeriformes: Hirundinidae in Ushuaia (Tierra del Fuego, Argentina

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Rosana Aramburú

2009-12-01

Full Text Available La golondrina chilena, Tachycineta meyeni (Cabanis, nidifica en el centro de Chile y suroeste de Argentina. En invierno migra a Bolivia, Paraguay y al sureste de Brasil. Estas golondrinas ocuparon una serie de cajas-nido en Ushuaia, Tierra del Fuego. Luego de la temporada de cría, tratamos los nidos con acetato de etilo y los revisamos en búsqueda de artrópodos hematófagos. Encontramos pulgas adultas, que fueron fijadas, aclaradas, deshidratadas, diafanizadas y montadas en un derivado de clavo de olor para su observación al microsocopio óptico. Identificamos machos y hembras de Dasypsyllus (Avesopsylla lasius lasius (Rothschild. En Argentina, esta pulga es conocida solamente en Sierra de la Ventana (Buenos Aires, donde se la halló parasitando la golondrina barranquera, Notiochelidon cyanoleuca patagonica (Vieillot. La información disponible debería complementarse con prospecciones en localidades intermedias. Otras aves relacionadas con ambas golondrinas por la ocupación de nidos, como el rayadito (Aphrastura spinicauda (Gmelin, ratona común (Troglodytes aedon Vieillot, caminera común (Geositta cunicularia (Vieillot, hornero (Furnarius rufus (Gmelin, podrían contribuir a la dispersión de la pulga entre las dos localidades registradas.Chilean swallows Tachycineta meyeni (Cabanis nest in the central area in Chile and Southwest in Argentina. In winter, they migrate to Bolivia, Paraguay and Southeast of Brazil. A nest box population of Chilean swallows was established in Ushuaia, Tierra del Fuego. After the breeding season, we collected all nests, treated them with ethyl acetate, and inspected all the nest material for hematophagous arthropods. We found adult fleas, which were fixed, cleared, diaphanized, dehydrated, and mounted in a clove derivative for observation under a microscope. We identified males and females of Dasypsyllus (Avesopsylla lasius lasius (Rothschild. In Argentina, this flea is only known for Sierra de la Ventana

AFLP markers for the R-gene in the flea beetle, Phyllotreta nemorum, conferring resistance to defenses in Barbarea vulgaris

NARCIS (Netherlands)

Breuker, C.J.; Victoir, K.; Jong, de P.W.; Meijden, van der E.; Brakefield, P.M.; Vrieling, K.

2005-01-01

A so-called R-gene renders the yellow-striped flea beetle Phyllotreta nemorum L. (Coleoptera: Chrysomelidae: Alticinae) resistant to the defenses of the yellow rocket Barbarea vulgaris R.Br. (Brassicacea) and enables it to use it as a host plant in Denmark. In this study, genetic markers for an

New contributions to the knowledge of Chinese flea beetle fauna (I); Gansuapteris new genus and Primulavorus new genus (Coleoptera; Chrysomelidae; Galerucinae)

Science.gov (United States)

Two new genera and species of flea beetles (Gansuapteris gen. nov., Primulavorus gen. nov., Gansuapteris fulvus sp. nov. and Primulavorus maculata sp. nov.) from South-west China are described and illustrated. The morphological differences of new genera and their allies are discussed....

Characterization of Spotted Fever Group Rickettsiae in Flea and Tick Specimens From Northern Peru

Science.gov (United States)

2004-11-01

boliviensis 3 (18.7) 1 (6.2) Ixodes pararicinus 2 (12.5) 0 Flea speciesb Adoratopsilla intermedia 2 (3.4) 0 Ctenocephalides felis 33 (55.9) 2 (3.4...analysis of a genus-common rickettsial antigen gene. J. Bacteriol. 171:5199–5201. 3. Azad, A. F., S. Radulovic, J. A. Higgins , B. H. Noden, and J. M...Y. Acad. Sci. 990:57–61. 21. Hackstadt, T. 1996. The biology of rickettsiae. Infect. Agents Dis. 5:127–143. 22. Higgins , J. A., S. Radulovic, M. E

Adverse reactions from essential oil-containing natural flea products exempted from Environmental Protection Agency regulations in dogs and cats.

Science.gov (United States)

Genovese, Allison G; McLean, Mary Kay; Khan, Safdar A

2012-08-01

To describe adverse effects in dogs and cats exposed to Environmental Protection Agency exempted plant-derived flea preventatives containing mixtures of essential oils. Retrospective study from 2006 to 2008. Records of dog and cat cases were reviewed from the American Society for the Prevention of Cruelty to Animals, Animal Poison Control Center database. Thirty-nine cats and 9 dogs with history of exposure to natural flea preventatives. The following information was retrieved from each incident: number of animals, species involved, frequency, types, onset time, duration of clinical signs, exposure appropriateness, final outcome, and treatment information. Ninety-two percent of animals (n = 44) showed presence of one or more adverse effects. The frequency of adverse effects in dogs (n = 8; 89%) and cats (n = 36; 92%) was similar. Onset time of adverse effects in 39 of 44 animals occurred within 24 hours. The duration of signs in 24 animals ranged from 30 minutes to 149 hours. The products were used as per label in 77% animals (n = 37). Of 28 animals with known outcome, 50% (n = 14) recovered with bathing alone while others received intravenous fluids, muscle relaxants, and anticonvulsive medications. Death (1 cat; n = 1/28; 4%) or euthanasia (1 cat and 1 dog; n = 2/28; 7%) was reported in 3 animals. Dogs and cats can experience significant adverse effects when exposed to plant-derived flea preventatives even when used according to label directions. The number of reports of exposure in cats was higher than dogs, but the frequency of reported adverse effects was similar between the 2 species. Agitation and hypersalivation were common in cats, whereas lethargy and vomiting were common in dogs. © Veterinary Emergency and Critical Care Society 2012.

Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCATÁN AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

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Gaspar PENICHE-LARA

2015-04-01

Full Text Available Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study’s results contributed to a better knowledge of Rickettsia epidemiology in Yucatán.

Rickettsia typhi in rodents and R. felis in fleas in Yucatán as a possible causal agent of undefined febrile cases.

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Peniche-Lara, Gaspar; Dzul-Rosado, Karla; Pérez-Osorio, Carlos; Zavala-Castro, Jorge

2015-01-01

Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study's results contributed to a better knowledge of Rickettsia epidemiology in Yucatán.

Myxomatosis: changes in the epidemiology of myxomatosis coincident with the establishment of the European rabbit flea Spilopsyllus cuniculi (Dale) in the Mallee region of Victoria.

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Shepherd, R C; Edmonds, J W

1978-12-01

Outbreaks of myxomatosis during the winter or spring have coincided with the establishment of the European rabbit flea in the Mallee region. The severity of these outbreaks has varied from causing complete suppression of the normal spring increase in rabbit numbers to being completely ineffective in a year in which late spring rains allowed rabbit breeding to extend into the early summer.In 1973 and 1974 effective spring myxomatosis caused heavy mortality in kittens before they emerged from the warrens. The age of the population increased as the result of few young rabbits coming into the population and of the lessened stress on old rabbits in a low summer-autumn population. This effect was reversed in the late-breeding year, 1976, when flea numbers were apparently too low to maintain a spring outbreak and rabbit numbers increased rapidly.

Viral haemorrhagic septicaemia virus (VHSV) remains viable for several days but at low levels in the water flea Moina macrocopa

DEFF Research Database (Denmark)

Ito, Takafumi; Olesen, Niels Jørgen

2017-01-01

in the water flea Moina macrocopa. VHSV was re-isolated from replicate groups of M. macrocopa that had been immersed with 108.0, 107.0, and 105.0 TCID50 ml-1 of VHSV (DK-3592B, Genotype Ia). Furthermore, 40 M. macrocopa that had been immersed with 108.0 TCID50 ml-1 of VHSV for 72 h had VHSV titers of 102...

Evaluation of the long-term efficacy and safety of an imidacloprid 10%/flumethrin 4.5% polymer matrix collar (Seresto® in dogs and cats naturally infested with fleas and/or ticks in multicentre clinical field studies in Europe

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Stanneck Dorothee

2012-03-01

Full Text Available Abstract Background The objective of these two GCP multicentre European clinical field studies was to evaluate the long-term efficacy and safety of a new imidacloprid/flumethrin collar (Seresto®, Bayer AnimalHealth, Investigational Veterinary Product(IVP in dogs and cats naturally infested with fleas and/or ticks in comparison to a dimpylat collar ("Ungezieferband fuer Hunde/fuer Katzen", Beaphar, Control Product (CP. Methods 232 (IVP and 81 (CP cats and 271(IVP and 129 (CP dogs were treated with either product according to label claims and formed the safety population. Flea and tick counts were conducted in monthly intervals for up to 8 months in the efficacy subpopulation consisting of 118 (IVP + 47 (CP cats and 197 (IVP + 94 (CP dogs. Efficacy was calculated as reduction of infestation rate within the same treatment group and statistically compared between the two treatment groups. Results Preventive efficacy against fleas in cats/dogs varied in the IVP group between 97.4%/94.1% and 100%/100% (overall mean: 98.3%/96.7% throughout the 8 month period and in the CP group between 57.1%/28.2% and 96.1%/67.8% (overall mean: 79.3%/57.9%. Preventive efficacy against ticks in cats/dogs varied in the IVP group between 94.0%/91.2% and 100%/100% (overall mean: 98.4%/94.7% throughout the 8 month period and in the CP group between 90.7%/79.9% and 100%/88.0% (overall mean: 96.9%/85.6%. The IVP group was statistically non-inferior to the CP group, and on various assessment days, statistical superiority was proven for flea and tick count reduction in dogs and cats. Both treatments proved to be safe in dogs and cats with mainly minor local observations at the application site. There was moreover, no incidence of any mechanical problem with the collar in dogs and cats during the entire study period. Conclusions The imidacloprid/flumethrin collar proved to reduce tick counts by at least 90% and flea counts by at least 95% for a period of at least 7-8 months in

Evaluation of the long-term efficacy and safety of an imidacloprid 10%/flumethrin 4.5% polymer matrix collar (Seresto®) in dogs and cats naturally infested with fleas and/or ticks in multicentre clinical field studies in Europe

Science.gov (United States)

2012-01-01

Background The objective of these two GCP multicentre European clinical field studies was to evaluate the long-term efficacy and safety of a new imidacloprid/flumethrin collar (Seresto®, Bayer AnimalHealth, Investigational Veterinary Product(IVP)) in dogs and cats naturally infested with fleas and/or ticks in comparison to a dimpylat collar ("Ungezieferband fuer Hunde/fuer Katzen", Beaphar, Control Product (CP)). Methods 232 (IVP) and 81 (CP) cats and 271(IVP) and 129 (CP) dogs were treated with either product according to label claims and formed the safety population. Flea and tick counts were conducted in monthly intervals for up to 8 months in the efficacy subpopulation consisting of 118 (IVP) + 47 (CP) cats and 197 (IVP) + 94 (CP) dogs. Efficacy was calculated as reduction of infestation rate within the same treatment group and statistically compared between the two treatment groups. Results Preventive efficacy against fleas in cats/dogs varied in the IVP group between 97.4%/94.1% and 100%/100% (overall mean: 98.3%/96.7%) throughout the 8 month period and in the CP group between 57.1%/28.2% and 96.1%/67.8% (overall mean: 79.3%/57.9%). Preventive efficacy against ticks in cats/dogs varied in the IVP group between 94.0%/91.2% and 100%/100% (overall mean: 98.4%/94.7%) throughout the 8 month period and in the CP group between 90.7%/79.9% and 100%/88.0% (overall mean: 96.9%/85.6%). The IVP group was statistically non-inferior to the CP group, and on various assessment days, statistical superiority was proven for flea and tick count reduction in dogs and cats. Both treatments proved to be safe in dogs and cats with mainly minor local observations at the application site. There was moreover, no incidence of any mechanical problem with the collar in dogs and cats during the entire study period. Conclusions The imidacloprid/flumethrin collar proved to reduce tick counts by at least 90% and flea counts by at least 95% for a period of at least 7-8 months in cats and dogs

New contributions to the knowledge of Chinese flea beetle fauna (III): Revision of Meishania Chen & Wang with description of five new species (Coleoptera: Chrysomelidae: Galerucinae)

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The flea beetle genus Meishania Chen & Wang is revised and five new species - M. cangshanensis sp. nov., M. flavipennis sp. nov., M. fulvotigera sp. nov., and M. sichuanica sp. nov. from China and M. bhutanensis sp. nov. from Bhutan - are described. All species of Meishania are illustrated and a key...

Influence de la température sur le développement de la puce africaine du chat Ctenocephalides felis strongylus (Jordan, 1925 (Siphonaptera : Pulicidae

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Yao K.P.

2010-06-01

Full Text Available Ctenocephalides felis (Bouché, 1835 communément appelée “puce du chat” présente deux sous-espèces reconnues : Ctenocephalides felis strongylus (Jordan, 1925 inféodée au continent africain et Ctenocephalides felis felis (Bouché, 1835 présente dans les zones à climat tempéré (Afrique du Nord, Europe et Amérique (Ménier et Beaucournu, 1999. En Afrique subsaharienne, la principale puce retrouvée chez les animaux de compagnie et chez certains animaux d’élevage (ovins, caprins et bovins appartient à la sous-espèce C. f. strongylus. Quelques paramètres bio-écologiques de C. f. strongylus ont été étudiés dans différentes conditions d’élevage. Les résultats ont été comparés à ceux de C. f. felis actuellement disponibles. À 75% ± 5 d’humidité relative, le cycle de développement de C. f. strongylus dure 20-21 jours à 27 °C et de 16 à 17 jours à 29 °C. Ainsi, la sousespèce africaine de la puce du chat (C. f. strongylus se développe moins vite que C. f. felis à températures identiques. Cette différence pourrait s’expliquer par l’influence du climat de leurs aires de distribution respectives sur leur cycle de développement. À 75% ± 5 d’humidité relative, les adultes de C. f. strongylus ne peuvent survivre plus de 14 jours dans l’environnement à des températures comprises entre 27 et 29 °C, lorsqu’elles n’ont jamais pris de repas sanguin. Dans ces mêmes conditions, la durée de survie n’excède pas 16 jours à 19 °C. Mais lorsque C. f. strongylus a pris un premier repas de sang, elle a une durée de vie beaucoup plus courte lorsqu’elle est hors de son hôte. En effet, aucun individu n’est retrouvé vivant trois jours passé hors de la fourrure de son hôte à 29 °C, cinq jours à 27 °C et huit jours à 19 °C. Il en est de même pour C. f. felis. Ces données sur la bio-écologie de C. f. strongylus permettent de comprendre l’influence de la température sur son cycle de développement et d’envisager des stratégies de lutte plus efficientes.

Isolation and characterization of a novel Rickettsia species (Rickettsia asembonensis sp. nov.) obtained from cat fleas (Ctenocephalides felis).

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Maina, Alice N; Luce-Fedrow, Alison; Omulo, Sylvia; Hang, Jun; Chan, Teik-Chye; Ade, Fredrick; Jima, Dereje D; Ogola, Eric; Ge, Hong; Breiman, Robert F; Njenga, Moses K; Richards, Allen L

2016-11-01

A novel rickettsial agent, 'Candidatus Rickettsia asembonensis' strain NMRCiiT, was isolated from cat fleas, Ctenocephalides felis, from Kenya. Genotypic characterization of the new isolate based on sequence analysis of five rickettsial genes, rrs, gltA, ompA, ompB and sca4, indicated that this isolate clustered with Rickettsia felis URRWXCal2. The degree of nucleotide similarity demonstrated that isolate NMRCiiT belongs within the genus Rickettsia and fulfils the criteria for classification as a representative of a novel species. The name Rickettsia asembonensis sp. nov. is proposed, with NMRCiiT (=DSM 100172T=CDC CRIRC RAS001T=ATCC VR-1827T) as the type strain.

Occurrence of the off-host life stages of Tunga penetrans (Siphonaptera) in various environments in Brazil.

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Linardi, P M; Calheiros, C M L; Campelo-Junior, E B; Duarte, E M; Heukelbach, J; Feldmeier, H

2010-06-01

To explore the local transmission dynamics of Tunga penetrans in brazil, 134 soil samples from various environments were collected in three different endemic regions of the country and checked for the presence of the flea's larvae, pupae and adults. the samples, which came from an urban slum in the north-east, a village of xavante indians in the central-west and a community of yanomami indians living in traditional longhouses (malocas) in the north, were categorized as indoor, outdoor or indoor-outdoor (the latter representing samples collected in the malocas). The proportion of samples found positive for T. penetrans was lowest in the slum (9.3%) and highest in the Yanomami village (32.0%; P=0.01). Soil samples collected below bedsteads or hammocks or from the indoor resting places of dogs were significantly more likely to be positive than the indoor samples collected at other sites (65.0% v. 35.0%; P=0.02). There was no evidence indicating that the presence of T. penetrans in a soil sample was markedly affected by soil temperature, air temperature or air humidity. As no life stages of T. penetrans were found in any outdoor sample, it seems likely that, in resource-poor settings in Brazil, most transmission of T. penetrans occurs indoors. Control measures against the off-host life stages of T. penetrans should therefore be targeted at particular indoor micro-environments.

Characterization of Hop-and-Sink Locomotion of Water Fleas

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Skipper, A. N.; Murphy, D. W.; Webster, D. R.

2017-11-01

The freshwater crustacean Daphnia magna is a widely studied zooplankton in relation to food webs, predator-prey interactions, and other biological/ecological considerations; however, their locomotion is poorly quantified and understood. These water fleas utilize a hop-and-sink mechanism that consists of making quick, impulsive jumps by beating their antennae to propel themselves forward (roughly 1 body length). The animals then sink for a period, during which they stretch out their antennae to increase drag and thereby reduce their sinking velocity. Time-resolved three-dimensional flow fields surrounding the animals were quantified with a unique infrared tomographic particle image velocimetry (tomo-PIV) system. Three-dimensional kinematics data were also extracted from the image sequences. In the current work, we compared body kinematics and flow disturbance among organisms of size in the range of 1.3 to 2.8 mm. The stroke cycle averaged 150 +/- 20 ms, with each stroke cycle split nearly evenly between power and recovery strokes. The kinematics data collapsed onto a self-similar curve when properly nondimensionalized, and a general trend was shown to exist between the nondimensionalized peak body speed and body length. The fluid flow induced by each antennae consisted of a viscous vortex ring that demonstrated a slow decay in the wake. The viscous dissipation showed no clear dependence on body size, whereas the volume of fluid exceeding 5 mm/s (the speed near the sinking speed of the animal) decayed more slowly with increasing body size.

Extract of the seeds of the plant Vitex agnus castus proven to be highly efficacious as a repellent against ticks, fleas, mosquitoes and biting flies.

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Mehlhorn, Heinz; Schmahl, Günter; Schmidt, Jürgen

2005-03-01

About 70 plant extracts were tested for their ability to repel the attacks of blood-sucking arthropods. It was found that a CO2 extract of the seeds of the Mediterranean plant Vitex agnus castus (monk's pepper) can be used as a spray to keep away especially Ixodes ricinus and Rhipicephalus sanguineus ticks from animals and humans for at least 6 h. In addition mosquitoes, biting flies and fleas are also repelled for about 6 h.

Seasonal fluctuations of small mammal and flea communities in a Ugandan plague focus: evidence to implicate Arvicanthis niloticus and Crocidura spp. as key hosts in Yersinia pestis transmission.

Science.gov (United States)

Moore, Sean M; Monaghan, Andrew; Borchert, Jeff N; Mpanga, Joseph T; Atiku, Linda A; Boegler, Karen A; Montenieri, John; MacMillan, Katherine; Gage, Kenneth L; Eisen, Rebecca J

2015-01-08

The distribution of human plague risk is strongly associated with rainfall in the tropical plague foci of East Africa, but little is known about how the plague bacterium is maintained during periods between outbreaks or whether environmental drivers trigger these outbreaks. We collected small mammals and fleas over a two year period in the West Nile region of Uganda to examine how the ecological community varies seasonally in a region with areas of both high and low risk of human plague cases. Seasonal changes in the small mammal and flea communities were examined along an elevation gradient to determine whether small mammal and flea populations exhibit differences in their response to seasonal fluctuations in precipitation, temperature, and crop harvests in areas within (above 1300 m) and outside (below 1300 m) of a model-defined plague focus. The abundance of two potential enzootic host species (Arvicanthis niloticus and Crocidura spp.) increased during the plague season within the plague focus, but did not show the same increase at lower elevations outside this focus. In contrast, the abundance of the domestic rat population (Rattus rattus) did not show significant seasonal fluctuations regardless of locality. Arvicanthis niloticus abundance was negatively associated with monthly precipitation at a six month lag and positively associated with current monthly temperatures, and Crocidura spp. abundance was positively associated with precipitation at a three month lag and negatively associated with current monthly temperatures. The abundance of A. niloticus and Crocidura spp. were both positively correlated with the harvest of millet and maize. The association between the abundance of several small mammal species and rainfall is consistent with previous models of the timing of human plague cases in relation to precipitation in the West Nile region. The seasonal increase in the abundance of key potential host species within the plague focus, but not outside of

Propulsion of the Water Flea, Daphnia magna: Experiments, Scaling, and Modelling

Science.gov (United States)

Skipper, A. N.; Murphy, D.; Webster, D. R.; Yen, J.

2016-02-01

The freshwater crustacean Daphnia magna is a widely studied zooplankton in relation to food webs, predator-prey interactions, and other biological/ecological considerations; however, their locomotion is poorly quantified and understood. These water fleas utilize a hop-and-sink mechanism that consists of making quick, impulsive jumps by beating their antennae to propel themselves forward ( 1 body length). The animals then sink for a period, during which they stretch out their antennae to increase drag and thereby reduce their sinking velocity. Time-resolved three-dimensional flow fields surrounding the animals were quantified with a unique infrared tomographic particle image velocity (tomo-PIV) system. Three-dimensional kinematics data were also extracted from the image sequences. In the current work, we compared body kinematics and flow disturbance among organisms of size in the range of 1.3 to 2.8 mm. The stroke cycle averaged 150 ms in duration, ranging from 100 to 180 ms; this period is generally evenly split between the power and recovery strokes. The range of peak hop velocity was 27.2 to 32.5 mm/s, and peak acceleration was in the range of 0.68 to 1.8 m/s2. The results showed a distinct relationship between peak hop speed (Vmax 14 BL/s) and body size; these data collapsed onto a single time-record curve during the power stroke when properly non-dimensionalized. The fluid flow induced by each antennae consisted of a viscous vortex ring that demonstrated a slow decay in the wake. The strength, size, and decay of the induced viscous vortex rings were compared as a function of organism size. Finally, the viscous vortex rings were analyzed in the context of a double Stokeslet model that consisted of two impulsively applied point forces separated by the animal width.

Deltamethrin flea-control preserves genetic variability of black-tailed prairie dogs during a plague outbreak

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Jones, P.H.; Biggins, D.E.; Eads, D.A.; Eads, S.L.; Britten, H.B.

2012-01-01

Genetic variability and structure of nine black-tailed prairie dog (BTPD, Cynomys ludovicianus) colonies were estimated with 15 unlinked microsatellite markers. A plague epizootic occurred between the first and second years of sampling and our study colonies were nearly extirpated with the exception of three colonies in which prairie dog burrows were previously dusted with an insecticide, deltamethrin, used to control fleas (vectors of the causative agent of plague, Yersinia pestis). This situation provided context to compare genetic variability and structure among dusted and non-dusted colonies pre-epizootic, and among the three dusted colonies pre- and post-epizootic. We found no statistical difference in population genetic structures between dusted and non-dusted colonies pre-epizootic. On dusted colonies, gene flow and recent migration rates increased from the first (pre-epizootic) year to the second (post-epizootic) year which suggested dusted colonies were acting as refugia for prairie dogs from surrounding colonies impacted by plague. Indeed, in the dusted colonies, estimated densities of adult prairie dogs (including dispersers), but not juveniles (non-dispersers), increased from the first year to the second year. In addition to preserving BTPDs and many species that depend on them, protecting colonies with deltamethrin or a plague vaccine could be an effective method to preserve genetic variability of prairie dogs. ?? 2011 Springer Science+Business Media B.V.

Flea beetles (Coleoptera: Chrysomelidae: Alticinae collected by malaise trap method in Gölcük Natural Park (Isparta, Turkey, with a new record for Turkish fauna

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Aslan Gül E.

2012-01-01

Full Text Available This study is based on Alticinae (Coleoptera: Chrysomelidae material collected by Malaise trapping which is different from other standardized collecting methods. A total of 19 flea beetle species belonging to 6 genera were collected from Gölcük Natural Park, Isparta (Turkey during 2009. The species are listed in a table together with distributional data in Turkey. Among them, Longitarsus curtus (Allard, 1860 is recorded for the first time in Turkey. L. monticola Kutschera, 1863 and L. curtus are recently separated synonyms and thus all data referring to the distribution of both species are currently important. Hence, the zoogeographical distribution of the new record is reviewed with some remarks; habitus and genitalia are illustrated.

[The biology of Dipylidium caninum. Part 2].

Science.gov (United States)

Hinaidy, H K

1991-07-01

From 198 cats and 182 dogs in Austria 9,134 fleas were collected. Ctenocephalides felis is the main flea of our cats (98.5%) and dogs (77.5%). Demonstration of cysticercoids of Dipylidium caninum through bleaching of fleas failed. Dissection of fleas gave, however, positive results. Each 44th flea from cats and 61st flea from dogs harbours cysticercoids. Infection intensity rates were 2.3% for C. felis (cats), 1.2% for C. felis (dogs), and 3.1% for C. canis (dogs). Male fleas are more extensively, but less intensively infected than female fleas. Cysticercoids form fleas of feline origin are more infective to cats than those from fleas found on dogs. The longest patency in cats lasted 3 years.

Gene expression profiling of three different stressors in the water flea Daphnia magna.

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Jansen, Mieke; Vergauwen, Lucia; Vandenbrouck, Tine; Knapen, Dries; Dom, Nathalie; Spanier, Katina I; Cielen, Anke; De Meester, Luc

2013-07-01

Microarrays are an ideal tool to screen for differences in gene expression of thousands of genes simultaneously. However, often commercial arrays are not available. In this study, we performed microarray analyses to evaluate patterns of gene transcription following exposure to two natural and one anthropogenic stressor. cDNA microarrays compiled of three life stage specific and three stressor-specific EST libraries, yielding 1734 different EST sequences, were used. We exposed juveniles of the water flea Daphnia magna for 48, 96 and 144 h to three stressors known to exert strong selection in natural populations of this species i.e. a sublethal concentration of the pesticide carbaryl, infective spores of the endoparasite Pasteuria ramosa, and fish predation risk mimicked by exposure to fish kairomones. A total of 148 gene fragments were differentially expressed compared to the control. Based on a PCA, the exposure treatments were separated into two main groups based on the extent of the transcriptional response: a low and a high (144 h of fish or carbaryl exposure and 96 h of parasite exposure) stress group. Firstly, we observed a general stress-related transcriptional expression profile independent of the treatment characterized by repression of transcripts involved in transcription, translation, signal transduction and energy metabolism. Secondly, we observed treatment-specific responses including signs of migration to deeper water layers in response to fish predation, structural challenge of the cuticle in response to carbaryl exposure, and disturbance of the ATP production in parasite exposure. A third important conclusion is that transcription expression patterns exhibit stress-specific changes over time. Parasite exposure shows the most differentially expressed gene fragments after 96 h. The peak of differentially expressed transcripts came only after 144 h of fish exposure, while carbaryl exposure induced a more stable number of differently expressed gene

Operational Mosquito and Vector-Borne Diseases Surveillance at Incirlik Air Base, Turkey

Science.gov (United States)

2017-05-23

of Biological Diversity , Columbus, OH, or the - cies and tested for arboviruses. Pools ranged from 1-25 mosquitoes depending on submission numbers...Rickettsia felis (Rickett- - phonaptera: Pulicidae) in the Philippines . J Ento- mol Sci. 2012;47:95-96. Mosquito surveillance data from Incirlik Air Base...Taylor SJ, Durden LA, Foley EH, Reeves WK. The bat tick Carios azteci (Acari: Argasidae) from Be- lize, with an endosymbiotic Coxiellaceae. Speleo

Detection of Bartonellaspp. and Rickettsiaspp. in fleas, ticks and lice collected in rural areas of Peru

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Abraham G. Cáceres

2013-12-01

Full Text Available Bartonellosis and rickettsiosis are commonly reported in Peru. In order to detect Bartonella sp. and Rickettsiasp. in fleas, ticks and lice, specimens from five distinct locations in Peru (Marizagua, Cajaruro, Jamalca, Lonya Grande and El Milagro were collected and screened for the presence of these bacteria using PCR and later confirmation by DNA sequencing. The specimens collected were distributed in 102 pools (76 Ctenocephalides felis, 2 Ctenocephalides canis, 16 Pulex irritans, 5 Pediculus humanus, 2 Rhiphicephalus sanguineus, and 1 Boophilus spp., where Bartonellawas detected in 17 pools (6 of C. felis, 9 of P. irritans, 1 of C. canis, and 1 P. humanus. Also, Rickettsiawas detected in 76 pools (62 C. felis, 10 P. irritans, 2 P. humanus, and 2 C. canis. Bartonella clarridgeiaewas detected in C. felis, C. canisand P. irritanspools at 5.3%, 50% and 12.5%, respectively.Bartonella rochalimaewas detected in one C. felisand two P. irritanspools at 1.3% and 12.5%, respectively. Furthermore, B. henselaewas detected in one C. felispool and one P. humanuspool corresponding to 1.3% and 20%, respectively; and Bartonella spp.was also found in 5 pools of P. irritansat 31.3%. Additionally, R. feliswas detected in C. felis, C. canisand P. irritanspools at 76.3%, 100% and 37.5%, respectively; and Rickettsia spp. was detected in C. felis, P. irritansand P. humanuspools at 5.3%, 25% and 40%, respectively. These results demonstrate the circulation of these bacteria in Peru.

Identification of Hepatozoon erhardovae Krampitz, 1964 from bank voles (Myodes glareolus) and fleas in Southern Hungary.

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Rigó, Krisztina; Majoros, Gábor; Szekeres, Sándor; Molnár, Imola; Jablonszky, Mónika; Majláthová, Viktória; Majláth, Igor; Földvári, Gábor

2016-06-01

In order to investigate the prevalence and life cycle of apicomplexan parasites, small mammals were live-trapped with modified Sherman traps in Southern Hungary between 2010 and 2012. Altogether, 528 rodents (Apodemus flavicollis Melchior, 1834, Apodemus agrarius Pallas, 1771, Myodes glareolus Schreber, 1780, Microtus agrestis Linnaeus, 1761, Mus musculus Linnaeus, 1758 and Micromys minutus Pallas, 1771) were collected and four shrews (Sorex spp.) were by-catched. Captured animals belonging to non-protected species were euthanized, and spleen samples were preserved for histological and molecular analyses. During the examination of spleen smears, Hepatozoon parasites were observed in eight out of 48 bank voles (M. glareolus). DNA was isolated from altogether 221 spleen samples, and 18S rDNA was amplified using two different PCR protocols. The eight bank vole samples were positive with PCR, but none of the other M. glareolus spleen samples or any of the tissue samples from other species were found to be infected. Sequenced amplicons were very similar to Hepatozoon spp. detected in M. glareolus in Spain and Poland. Ectoparasites were collected from the small mammal carcasses and from the vegetation. Hepatozoon DNA was not found in the 181 ticks removed from the small mammals or in the 162 ticks collected with flagging, but was detected in all three flea species (4/43 Megabothris turbidus Rothschild, 1909, 3/10 Ctenophthalmus assimilis Taschenberg, 1880 and 7/78 Ctenophthalmus agyrtes Heller, 1896). Based on gamont morphology, vertebrate and arthropod host species and DNA sequences, the parasites in our study can be identified as Hepatozoon erhardovae.

Plague cycles in two rodent species from China: Dry years might provide context for epizootics in wet years

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Eads, David A.; Biggins, Dean E.; Xu, Lei; Liu, Qiyong

2016-01-01

Plague, a rodent-associated, flea-borne zoonosis, is one of the most notorious diseases in history. Rates of plague transmission can increase when fleas are abundant. Fleas commonly desiccate and die when reared under dry conditions in laboratories, suggesting fleas will be suppressed during droughts in the wild, thus reducing the rate at which plague spreads among hosts. In contrast, fleas might increase in abundance when precipitation is plentiful, producing epizootic outbreaks during wet years. We tested these hypotheses using a 27-yr data set from two rodents in Inner Mongolia, China: Mongolian gerbils (Meriones unguiculatus) and Daurian ground squirrels (Spermophilus dauricus). For both species of rodents, fleas were most abundant during years preceded by dry growing seasons. For gerbils, the prevalence of plague increased during wet years preceded by dry growing seasons. If precipitation is scarce during the primary growing season, succulent plants decline in abundance and, consequently, herbivorous rodents can suffer declines in body condition. Fleas produce more offspring and better survive when parasitizing food-limited hosts, because starving animals tend to exhibit inefficient behavioral and immunological defenses against fleas. Further, rodent burrows might buffer fleas from xeric conditions aboveground during dry years. After a dry year, fleas might be abundant due to the preceding drought, and if precipitation and succulent plants become more plentiful, rodents could increase in density, thereby creating connectivity that facilitates the spread of plague. Moreover, in wet years, mild temperatures might increase the efficiency at which fleas transmit the plague bacterium, while also helping fleas to survive as they quest among hosts. In this way, dry years could provide context for epizootics of plague in wet years.

LA TITUDE-LONGITUDE GRID MAPS OF AFRICA (CCTA ...

African Journals Online (AJOL)

of mapping see de Meillon, B., Davis, D. H. S., and Hardy, F., Plague in Southern Mrica. I. The Siphonaptera. Government Printer, Pretoria, 1961, or consult CCTAjCSA Publication. No. 29, referred to above. * Climatological Atlas of Africa, compiled and edited in the African Climatology Unit, University of the. Witwatersrand ...

Burrowing Owls, Pulex irritans, and Plague.

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Belthoff, James R; Bernhardt, Scott A; Ball, Christopher L; Gregg, Michael; Johnson, David H; Ketterling, Rachel; Price, Emily; Tinker, Juliette K

2015-09-01

Western Burrowing Owls (Athene cunicularia hypugaea) are small, ground-dwelling owls of western North America that frequent prairie dog (Cynomys spp.) towns and other grasslands. Because they rely on rodent prey and occupy burrows once or concurrently inhabited by fossorial mammals, the owls often harbor fleas. We examined the potential role of fleas found on burrowing owls in plague dynamics by evaluating prevalence of Yersinia pestis in fleas collected from burrowing owls and in owl blood. During 2012-2013, fleas and blood were collected from burrowing owls in portions of five states with endemic plague-Idaho, Oregon, Washington, Colorado, and South Dakota. Fleas were enumerated, taxonomically identified, pooled by nest, and assayed for Y. pestis using culturing and molecular (PCR) approaches. Owl blood underwent serological analysis for plague antibodies and nested PCR for detection of Y. pestis. Of more than 4750 fleas collected from owls, Pulex irritans, a known plague vector in portions of its range, comprised more than 99.4%. However, diagnostic tests for Y. pestis of flea pools (culturing and PCR) and owl blood (PCR and serology) were negative. Thus, even though fleas were prevalent on burrowing owls and the potential for a relationship with burrowing owls as a phoretic host of infected fleas exists, we found no evidence of Y. pestis in sampled fleas or in owls that harbored them. We suggest that studies similar to those reported here during plague epizootics will be especially useful for confirming these results.

Comparative ecotoxicity of potential biofuels to water flea (Daphnia magna), zebrafish (Danio rerio) and Chinese hamster (Cricetulus griseus) V79 cells.

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Heger, Sebastian; Du, Miaomiao; Bauer, Kevin; Schäffer, Andreas; Hollert, Henner

2018-08-01

The ecotoxicity of two biofuel candidates (1‑octanol and 2‑butanone) was investigated by an integrative test strategy using three bioassays: the acute immobilisation test with water flea (D. magna), the fish embryo acute toxicity test with zebrafish (Danio rerio) and the in vitro micronucleus assay with Chinese hamster (Cricetulus griseus) V79 cells. The median effective concentration (EC 50 ) values were 14.9±0.66mgL -1 for 1‑octanol, and 2152.1±44.6mgL -1 for 2‑butanone in the D. magna test. Both 1‑octanol and 2‑butanone caused teratogenic and lethal effects on zebrafish embryos, while exposure to 1‑octanol significantly induced these effects at concentrations ≥2.0mgL -1 . These results indicate that 1‑octanol exert much higher ecotoxicity than 2‑butanone to D. magna and zebrafish embryos. Moreover, both 1‑octanol and 2‑butanone did not cause significant genotoxic effects, while their metabolites significantly induced micronuclei in V79 cells. The present study proposed an integrative test approach to evaluate the potential ecotoxicity of biofuels using simple, quick and inexpensive bioassays. Copyright © 2018 Elsevier B.V. All rights reserved.

Ixodes ricinus ticks are reservoir hosts for Rickettsia helvetica and potentially carry flea-borne Rickettsia species

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Gaasenbeek Cor

2009-09-01

Full Text Available Abstract Background Hard ticks have been identified as important vectors of rickettsiae causing the spotted fever syndrome. Tick-borne rickettsiae are considered to be emerging, but only limited data are available about their presence in Western Europe, their natural life cycle and their reservoir hosts. Ixodes ricinus, the most prevalent tick species, were collected and tested from different vegetation types and from potential reservoir hosts. In one biotope area, the annual and seasonal variability of rickettsiae infections of the different tick stages were determined for 9 years. Results The DNA of the human pathogen R. conorii as well as R. helvetica, R. sp. IRS and R. bellii-like were found. Unexpectedly, the DNA of the highly pathogenic R. typhi and R. prowazekii and 4 other uncharacterized Rickettsia spp. related to the typhus group were also detected in I. ricinus. The presence of R. helvetica in fleas isolated from small rodents supported our hypothesis that cross-infection can occur under natural conditions, since R. typhi/prowazekii and R. helvetica as well as their vectors share rodents as reservoir hosts. In one biotope, the infection rate with R. helvetica was ~66% for 9 years, and was comparable between larvae, nymphs, and adults. Larvae caught by flagging generally have not yet taken a blood meal from a vertebrate host. The simplest explanation for the comparable prevalence of R. helvetica between the defined tick stages is, that R. helvetica is vertically transmitted through the next generation with high efficiency. The DNA of R. helvetica was also present in whole blood from mice, deer and wild boar. Conclusion Besides R. helvetica, unexpected rickettsiae are found in I. ricinus ticks. We propose that I. ricinus is a major reservoir host for R. helvetica, and that vertebrate hosts play important roles in the further geographical dispersion of rickettsiae.

Ectoparasitos de roedores da região urbana de Belo Horizonte, MG: III. Indices pulicidianos, anoplurianos e acarianos em Rattus Norvegicus norvegicus Ectoparasites in rodents of the urban region of Belo Horizonte, MG: III. Fleas, anoplura and acari indices in Rattus norvegicus norvegicus

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Pedro Marcos Linardi

1985-09-01

Full Text Available Indices pulicidianos, anoplurianos e acarianos, globais e específicos foram determinados para os ectoparasitos de Rattus norvegicus norvegicus capturados em zona urbana de Belo Horizonte, Minas Gerais, Brasil, no período de junho de 1980 a setembro de 1982. Tendo-se em vista os valores limites ou críticos atribuídos aos índices pulicidianos, sobretudo ao índice "cheopis" e propostos por diversos autores como medida complementar de vigilância epidemiológica para peste bubônica, a comunidade de Belo Horizonte poderia ter estado exposta a esta infecção, uma vez que os índices globais anuais de 0,3 a 2,4 e a pulga prevalente foi Xenopsylla cheopis (99,2%, com os maiores índices coincidindo com o final da estação seca-fria. Em duas ocasiões, a comunidade poderia ter permanecido altamente exposta à infecção, já que os índices-limites tolerados foram suplantados: 8,8 (outubro 1980 e 6,2 (setembro 1982. Sugere-se que medidas profiláticas como anti-ratização e desinsetização sejam eficazmente aplicadas ao final da estação seca-fria, ou anteriormente à chegada das chuvas, sendo sucedidas pela desratização. Informações sobre índices anoplurianos e acarianos são importantes para que se possa, no exclusivas de roedoresThe total and specific indices of fleas, lice and mites were determined for ectoparasites on Rattus norvegicus norvegicus capture in urban areas of Belo Horizonte, Minas state, Brazil, from June 1980 to September 1982. In view of the limiting or critical values attributed to flea indices above all the [quot ]cheopis[quot ] index, proposed by several authors as a complementary measure for bubonic plague surveillance, the community of Belo Horizonte would have been exposed to this infection. The annual total indices ranged from 0.3 to 2.4 and the prevalent flea was Xenopsylla cheopis (99.2%, with the highest indices coinciding with the late dry-cool season. On two occasions, in this period, the community would

Infestasi pinjal dan infeksi Dipylidium caninum Linnaeus pada kucing liar di lingkungan kampus Institut Pertanian Bogor, Kecamatan Dramaga

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Aulia Syifak Bashofi

2016-02-01

Full Text Available This study was conducted to investigate flea infestation and Dipylidium caninum (Linnaeus 1758 infection on stray cat on Bogor Agricultural University Dramaga. Thirty stray cats were collected from various places around on Bogor Agricultural University Dramaga. The stray cats that showed clinical signs of pruritus and alopecia were collected purposively. The whole body was powdered by gamexan powder, after that the fleas were collected by manual and examined microscopically. The totals of 30 fecal stray cat samples collected and examined toward D. caninum used Mcmaster methode, flotation methode, and saw the existence of proglottid. The result of identification showed that there was found one species of flea, namely Ctenocephalides felis (Bouche 1835, while on faeces was not found D. caninum. Twenty one stray cats were infected by the flea with density average of fleas per cat was 3.8 ± 1.9 individual.

Comparative Global Gene Expression Profiles of Wild-Type Yersinia pestis CO92 and Its Braun Lipoprotein Mutant at Flea and Human Body Temperatures

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Cristi L. Galindo

2010-01-01

Full Text Available Braun/murein lipoprotein (Lpp is involved in inflammatory responses and septic shock. We previously characterized a Δlpp mutant of Yersinia pestis CO92 and found that this mutant was defective in surviving in macrophages and was attenuated in a mouse inhalation model of plague when compared to the highly virulent wild-type (WT bacterium. We performed global transcriptional profiling of WT Y. pestis and its Δlpp mutant using microarrays. The organisms were cultured at 26 and 37 degrees Celsius to simulate the flea vector and mammalian host environments, respectively. Our data revealed vastly different effects of lpp mutation on the transcriptomes of Y. pestis grown at 37 versus 26C. While the absence of Lpp resulted mainly in the downregulation of metabolic genes at 26C, the Y. pestis Δlpp mutant cultured at 37C exhibited profound alterations in stress response and virulence genes, compared to WT bacteria. We investigated one of the stress-related genes (htrA downregulated in the Δlpp mutant relative to WT Y. pestis. Indeed, complementation of the Δlpp mutant with the htrA gene restored intracellular survival of the Y. pestis Δlpp mutant. Our results support a role for Lpp in Y. pestis adaptation to the host environment, possibly via transcriptional activation of htrA.

Enzootic plague reduces black-footed ferret (Mustela nigripes) survival in Montana

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Matchett, Marc R.; Biggins, Dean E.; Carlson, Valerie; Powell, Bradford; Rocke, Tonie E.

2010-01-01

Black-footed ferrets (Mustela nigripes) require extensive prairie dog colonies (Cynomys spp.) to provide habitat and prey. Epizootic plague kills both prairie dogs and ferrets and is a major factor limiting recovery of the highly endangered ferret. In addition to epizootics, we hypothesized that enzootic plague, that is, presence of disease-causing Yersinia pestis without any noticeable prairie dog die off, may also affect ferret survival. We reduced risk of plague on portions of two ferret reintroduction areas by conducting flea control for 3 years. Beginning in 2004, about half of the ferrets residing on dusted and nondusted colonies were vaccinated against plague with an experimental vaccine (F1-V fusion protein). We evaluated 6-month reencounter rates (percentage of animals observed at the end of an interval that were known alive at the beginning of the interval), an index to survival, for ferrets in four treatment groups involving all combinations of vaccination and flea control. For captive-reared ferrets (115 individuals observed across 156 time intervals), reencounter rates were higher for vaccinates (0.44) than for nonvaccinates (0.23, p = 0.044) on colonies without flea control, but vaccination had no detectable effect on colonies with flea control (vaccinates = 0.41, nonvaccinates = 0.42, p = 0.754). Flea control resulted in higher reencounter rates for nonvaccinates (p = 0.026), but not for vaccinates (p = 0.508). The enhancement of survival due to vaccination or flea control supports the hypothesis that enzootic plague reduces ferret survival, even when there was no noticeable decline in prairie dog abundance. The collective effects of vaccination and flea control compel a conclusion that fleas are required for maintenance, and probably transmission, of plague at enzootic levels. Other studies have demonstrated similar effects of flea control on several species of prairie dogs and, when combined with this study, suggest

Resistance to Innate Immunity Contributes to Colonization of the Insect Gut by Yersinia pestis.

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Shaun C Earl

Full Text Available Yersinia pestis, the causative agent of bubonic and pneumonic plague, is typically a zoonotic vector-borne disease of wild rodents. Bacterial biofilm formation in the proventriculus of the flea contributes to chronic infection of fleas and facilitates efficient disease transmission. However prior to biofilm formation, ingested bacteria must survive within the flea midgut, and yet little is known about vector-pathogen interactions that are required for flea gut colonization. Here we establish a Drosophila melanogaster model system to gain insight into Y. pestis colonization of the insect vector. We show that Y. pestis establishes a stable infection in the anterior midgut of fly larvae, and we used this model system to study the roles of genes involved in biofilm production and/or resistance to gut immunity stressors. We find that PhoP and GmhA both contribute to colonization and resistance to antimicrobial peptides in flies, and furthermore, the data suggest biofilm formation may afford protection against antimicrobial peptides. Production of reactive oxygen species in the fly gut, as in fleas, also serves to limit bacterial infection, and OxyR mediates Y. pestis survival in both insect models. Overall, our data establish the fruit fly as an informative model to elucidate the relationship between Y. pestis and its flea vector.

Detections of Yersinia pestis East of the Known Distribution of Active Plague in the United States.

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Mize, Erica L; Britten, Hugh B

2016-02-01

We examined fleas collected from black-tailed prairie dog (Cynomys ludovicianus) burrows from 2009 through 2011 in five national park units east of the known distribution of active plague across the northern Great Plains for the presence of Yersinia pestis. Across all national park units, Oropsylla tuberculata and Oropsylla hirsuta were the most common fleas collected from prairie dog burrows, 42.4% and 56.9%, respectively, of the 3964 fleas collected from burrow swabbing. Using a nested PCR assay, we detected 200 Y. pestis-positive fleas from 3117 assays. In total, 6.4% of assayed fleas were Y. pestis positive and 13.9% of prairie dog burrows swabbed contained Y. pestis-positive fleas. Evidence of the presence of Y. pestis was observed at all national park units except Devils Tower National Monument in Wyoming. We detected the presence of Y. pestis without large die-offs, i.e., enzootic sylvatic plague, east of the known distribution of active plague and near the eastern edge of the present distribution of black-tailed prairie dogs. This study, in combination with previous work suggests that sylvatic plague likely occurs across the range of black-tailed prairie dogs and should now be treated as endemic across this range.

Bartonella infection in shelter cats and dogs and their ectoparasites.

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Tsai, Yi-Lun; Lin, Chao-Chen; Chomel, Bruno B; Chuang, Shih-Te; Tsai, Kun-Hsien; Wu, Wen-Jer; Huang, Chin-Gi; Yu, Jiann-Chung; Sung, Min-Hua; Kass, Philip H; Chang, Chao-Chin

2011-08-01

Mainly through vector transmission, domestic cats and dogs are infected by several Bartonella spp. and represent a large reservoir for human infections. This study investigated the relationship of prevalences of Bartonella infection in shelter dogs and cats and various ectoparasite species infesting them (fleas, ticks, and lice). Moreover, relationships between Bartonella infection and animal gender and age and presence of ectoparasites were analyzed. Blood samples were collected from 120 dogs and 103 cats. There were 386 ticks and 36 fleas harvested on these dogs, and 141 fleas, 4 ticks, and 2 lice harvested on these cats. Isolation/detection of Bartonella sp. was performed by culture, polymerase chain reaction (PCR), and partial sequencing. Bartonella was isolated from 21 (20.4%) cats and detected by PCR from 20 (19.4%) cats, 2 (1.7%) dogs, 55 (39%) fleas collected from cats, 28 (10%) ticks DNA samples, and 1 (2.8%) flea collected from dogs. When combining culture and PCR data, 27 cats and 55 fleas collected on cats were positive for Bartonella henselae or Bartonella clarridgeiae, but none were coinfected. Approximately half of the B. henselae isolates from 21 cats were B. henselae type I. Moreover, B. henselae, Bartonella phoceensis, Bartonella queenslandensis, Bartonella rattimassiliensis, Bartonella elizabethae DNA was detected in ticks collected from dogs and one flea was B. clarridgeiae PCR positive. This is the first report of such a wide variety of Bartonella spp. detected in Rhipicephalus sanguineus. Further studies are required to understand the relative importance of these ectoparasites to transmit Bartonella spp. in dogs and cats.

Identification of Risk Factors Associated with Transmission of Plague Disease in Eastern Zambia.

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Nyirenda, Stanley S; Hang'ombe, Bernard M; Machang'u, Robert; Mwanza, Jackson; Kilonzo, Bukheti S

2017-09-01

Plague is a fatal, primarily rodent-flea-borne zoonotic disease caused by Yersinia pestis . The identification of risk factors of plague was investigated through questionnaire interview and conducting focus group discussion (FGD) in Sinda and Nyimba districts of eastern Zambia. A total of 104 questionnaires were administered to individual respondents and 20 groups consisting of 181 discussants, which comprised FGD team in this study. The study revealed that trapping, transportation, and preparation of rodents for food exposed the community to rodent and their fleas suggesting that plague may have occurred primarily by either flea bites or contact with infected wild rodents. The study also revealed that most people in communities consumed rodents as part of their regular diet; therefore, contact with small wild mammals was a common practice. The mode of transportation of freshly trapped rodents, in particular, carcasses risked human to flea bites. Questionnaire respondents (75%) and FGD discussants (55%) indicated that trappers preferred to carry rodent carcasses in small bags, whereas 55.8% and 20% respectively, reported hunters carrying carcasses in their pockets. Carrying of carcass skewers on trappers' shoulders was reported by 38.4% and 20% of individual respondents and FGD, respectively. All these activities were exposing humans to rodents and their fleas, the natural reservoirs and vectors of plague, respectively. This study also showed that there is a statistically significant (χ 2 = 4.6878, P < 0.05), between digging of rodents from their burrows and the presence of fleas on the hunter's bodies or clothes, which exposes humans to potentially flea bites in an enzootic cycle.

Human Dipylidiasis: A Case Report of Dipylidium caninum Infection from Karimnagar

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KV Ramana

2011-07-01

Full Text Available Dipylidium caninum also refered to as the double-pored tapeworm is a cyclophyllidean cestode that commonly infects dogs and cats. Mammals act as definite hosts with intermediate hosts being dog and cat flea, the Ctenocephalides canis and Ctenocephalides catis respectively. The dog lice, Trichodectes canis and human flea (Pulex irritans also transmit Dipylidium caninum infection. Infants and young children are at high risk of acquiring infection. Majority of the infections are due to close association with pet dog and cats. Humans are accidental hosts who acquire infection by ingestion of infected dog and cat fleas. We report a rare case of Dipylidium caninum infection in a 9 year old girl who could have acquired infection by consuming food contaminated with infected fleas.

Differential Rickettsial Transcription in Bloodfeeding and Non-Bloodfeeding Arthropod Hosts.

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Victoria I Verhoeve

Full Text Available Crucial factors influencing the epidemiology of Rickettsia felis rickettsiosis include pathogenesis and transmission. Detection of R. felis DNA in a number of arthropod species has been reported, with characterized isolates, R. felis strain LSU and strain LSU-Lb, generated from the cat flea, Ctenocephalides felis, and the non-hematophagous booklouse, Liposcelis bostrychophila, respectively. While it is realized that strain influence on host biology varies, the rickettsial response to these distinct host environments remained undefined. To identify a panel of potential rickettsial transmission determinants in the cat flea, the transcriptional profile for these two strains of R. felis were compared in their arthropod hosts using RNAseq. Rickettsial genes with increased transcription in the flea as compared to the booklouse were identified. Genes previously associated with bacterial virulence including LPS biosynthesis, Type IV secretion system, ABC transporters, and a toxin-antitoxin system were selected for further study. Transcription of putative virulence-associated genes was determined in a flea infection bioassay for both strains of R. felis. A host-dependent transcriptional profile during bloodfeeding, specifically, an increased expression of selected transcripts in newly infected cat fleas and flea feces was detected when compared to arthropod cell culture and incubation in vertebrate blood. Together, these studies have identified novel, host-dependent rickettsial factors that likely contribute to successful horizontal transmission by bloodfeeding arthropods.

Geographical and Temporal Dynamics of Chaetocnema Pulicaria and Their Role in Stewart's Disease of Corn in Iowa

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Esker, Paul David [Iowa State Univ., Ames, IA (United States)

2001-01-01

This thesis investigated the biology and importance of the corn flea beetle vector and its role in the Stewart's disease of corn pathosystem. This was accomplished by determining the number of corn flea beetle generations that occur in Iowa and by quantifying the proportions of those populations found to be infested with the causal agent of Stewart's disease, pantoea stewartii. In addition, a preliminary study was conducted to determine how soil temperature was influenced by air temperature and how this may be applied to forecasting for Stewart's disease of corn. Research using yellow sticky cards and sweep netting demonstrated that there are overwintering, first, and second field generations of the corn flea beetle in Iowa. It was also observed that there was a period during June of both 1999 and 2000 when corn flea beetles were not found, which is important new management information. This research has also demonstrated that the incidence of P. stewartii-infested corn flea beetles can be monitored by ELISA testing and that the incidence fluctuates greatly throughout the corn growing season. The initial level of inoculum (P. stewartii-infested corn flea beetles in the adult overwintering generation) does not remain static during the spring as was previously hypothesized. This signals that additional research is needed concerning the mechanisms of fluctuation in the proportion of beetles infested with P. stewartii.

Genomic Diversification in Strains of Rickettsia felis Isolated from Different Arthropods

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Gillespie, Joseph J.; Driscoll, Timothy P.; Verhoeve, Victoria I.; Utsuki, Tadanobu; Husseneder, Claudia; Chouljenko, Vladimir N.; Azad, Abdu F.; Macaluso, Kevin R.

2015-01-01

Rickettsia felis (Alphaproteobacteria: Rickettsiales) is the causative agent of an emerging flea-borne rickettsiosis with worldwide occurrence. Originally described from the cat flea, Ctenocephalides felis, recent reports have identified R. felis from other flea species, as well as other insects and ticks. This diverse host range for R. felis may indicate an underlying genetic variability associated with host-specific strains. Accordingly, to determine a potential genetic basis for host specialization, we sequenced the genome of R. felis str. LSU-Lb, which is an obligate mutualist of the parthenogenic booklouse Liposcelis bostrychophila (Insecta: Psocoptera). We also sequenced the genome of R. felis str. LSU, the second genome sequence for cat flea-associated strains (cf. R. felis str. URRWXCal2), which are presumably facultative parasites of fleas. Phylogenomics analysis revealed R. felis str. LSU-Lb diverged from the flea-associated strains. Unexpectedly, R. felis str. LSU was found to be divergent from R. felis str. URRWXCal2, despite sharing similar hosts. Although all three R. felis genomes contain the pRF plasmid, R. felis str. LSU-Lb carries an additional unique plasmid, pLbaR (plasmid of L. bostrychophila associated Rickettsia), nearly half of which encodes a unique 23-gene integrative conjugative element. Remarkably, pLbaR also encodes a repeats-in-toxin-like type I secretion system and associated toxin, heretofore unknown from other Rickettsiales genomes, which likely originated from lateral gene transfer with another obligate intracellular parasite of arthropods, Cardinium (Bacteroidetes). Collectively, our study reveals unexpected genomic diversity across three R. felis strains and identifies several diversifying factors that differentiate facultative parasites of fleas from obligate mutualists of booklice. PMID:25477419

The Role of the United States Military in the Development of Vector Control Products, Including Insect Repellents, Insecticides, and Bed Nets

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2009-06-01

Kondig, R. Fernandez, and F. Carbajal. 2004. Field detection of eastern equine encephalitis virus in the Amazon Basin region of Peru using reverse...Yes (fleas) 26. Q fever Yes (argasid ticks) 27. Plague Yes ( rodent fleas) 28. Venezuelan equine encephalitis Yes (Culex and Psorophora mosquitoes) 29

Temporal and spatial distribution characteristics in the natural plague foci of Chinese Mongolian gerbils based on spatial autocorrelation.

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Du, Hai-Wen; Wang, Yong; Zhuang, Da-Fang; Jiang, Xiao-San

2017-08-07

The nest flea index of Meriones unguiculatus is a critical indicator for the prevention and control of plague, which can be used not only to detect the spatial and temporal distributions of Meriones unguiculatus, but also to reveal its cluster rule. This research detected the temporal and spatial distribution characteristics of the plague natural foci of Mongolian gerbils by body flea index from 2005 to 2014, in order to predict plague outbreaks. Global spatial autocorrelation was used to describe the entire spatial distribution pattern of the body flea index in the natural plague foci of typical Chinese Mongolian gerbils. Cluster and outlier analysis and hot spot analysis were also used to detect the intensity of clusters based on geographic information system methods. The quantity of M. unguiculatus nest fleas in the sentinel surveillance sites from 2005 to 2014 and host density data of the study area from 2005 to 2010 used in this study were provided by Chinese Center for Disease Control and Prevention. The epidemic focus regions of the Mongolian gerbils remain the same as the hot spot regions relating to the body flea index. High clustering areas possess a similar pattern as the distribution pattern of the body flea index indicating that the transmission risk of plague is relatively high. In terms of time series, the area of the epidemic focus gradually increased from 2005 to 2007, declined rapidly in 2008 and 2009, and then decreased slowly and began trending towards stability from 2009 to 2014. For the spatial change, the epidemic focus regions began moving northward from the southwest epidemic focus of the Mongolian gerbils from 2005 to 2007, and then moved from north to south in 2007 and 2008. The body flea index of Chinese gerbil foci reveals significant spatial and temporal aggregation characteristics through the employing of spatial autocorrelation. The diversity of temporary and spatial distribution is mainly affected by seasonal variation, the human

Status of Job Motivation and Job Performance of Field Level Extension Agents in Ogun State: Implications for Agricultural Development

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Fabusoro, E.; Awotunde, J. A.; Sodiya, C. I.; Alarima, C. I.

2008-01-01

The field level extension agents (FLEAs) are the lifeline of the agricultural extension system in Nigeria. Their motivation and job performance are therefore important to achieving faster agricultural development in Nigeria. The study identified the factors motivating the FLEAs working with Ogun State Agricultural development programme (OGADEP)…

Efficacy of materials used by resource limited farmers in ethno ...

African Journals Online (AJOL)

zino

2013-04-03

Apr 3, 2013 ... and efficacy of selected materials used in the control fleas in free-range chickens. The materials tested .... Mature fleas, Ctenocephalides felis of mixed sex were obtained from Clinvet ... were bought from one farmer in the Amatola basin. In addition, ..... Ababa University of School of graduate studies.

77 FR 40039 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

Science.gov (United States)

2012-07-06

... Flea & Gardona (cis- Tick Spray with isomer). Deodorant for Dogs III. 002596-00123 Hartz 2 in 1 Fast Gardona (cis- Acting Flea & Tick isomer). Spray for Cats With Rabon. 002724-00651 Farnam Natural Bug... the food or feed crops associated with the domestic use of carbofuran products, and there have been...

Is the U.S. Navy Prepared to Counter Biological Warfare Threats?

Science.gov (United States)

2001-12-01

Unit 731 set up flea “nurseries” for the production of 135 million plague-infested fleas every four months. As a delivery system, porcelain bombs...operations is important, naval doctrine and TTPs should allow NSF to conduct CM alone in an emergency.141 The Chinese have an ancient saying, “kill

Rickettsioses in Europe.

Science.gov (United States)

Portillo, Aránzazu; Santibáñez, Sonia; García-Álvarez, Lara; Palomar, Ana M; Oteo, José A

2015-01-01

Bacteria of the genera Rickettsia and Orientia (family rickettsiaceae, order rickettsiales) cause rickettsioses worldwide, and are transmitted by lice, fleas, ticks and mites. In Europe, only Rickettsia spp. cause rickettsioses. With improvement of hygiene, the risk of louse-borne rickettsiosis (epidemic typhus) is low in Europe. Nevertheless, recrudescent form of Rickettsia prowazekii infection persists. There could be an epidemic typhus outbreak if a body lice epidemic occurs under unfavorable sanitary conditions. In Europe, endemic typhus or Rickettsia typhi infection, transmitted by rats and fleas, causes febrile illness. At the beginning of this century, flea-borne spotted fever cases caused by Rickettsia felis were diagnosed. Flea-borne rickettsiosis should be suspected after flea bites if fever, with or without rash, is developed. Tick-borne rickettsioses are the main source of rickettsia infections in Europe. Apart from Rickettsia conorii, the Mediterranean Spotted Fever (MSF) agent, other Rickettsia spp. cause MSF-like: Rickettsia helvetica, Rickettsia monacensis, Rickettsia massiliae or Rickettsia aeschlimannii. In the 1990s, two 'new' rickettsioses were diagnosed: Lymphangitis Associated Rickettsiosis (LAR) caused by Rickettsia sibirica mongolitimonae, and Tick-Borne Lymphadenopathy/Dermacentor-Borne-Necrosis-Erythema-Lymphadenopathy/Scalp Eschar Neck Lymphadenopathy (TIBOLA/DEBONEL/SENLAT), caused by Rickettsia slovaca, Candidatus Rickettsia rioja and Rickettsia raoultii. Lastly, European reports about mite-borne rickettsiosis are scarce. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

ectoparasites of the bush cep.a.pi, in the transvaal (rodentia: sciuridae)

African Journals Online (AJOL)

plague in Mrica and in some places it is probably the main vector. An additional record of the flea,. Xenopsylla sp., was also recorded from Naboom- spruit (July). The cat flea, CtenocepluJlidesfelis, is widespread over Mrica on Canidae, Felidae, Viver- ridae, Hyaenidae and Leporidae as well as on domestic animals and ...

Vector control improves survival of three species of prairie dogs (Cynomys) in areas considered enzootic for plague

Science.gov (United States)

Biggins, Dean E.; Godbey, Jerry L.; Gage, Kenneth L.; Carter, Leon G.; Montenieri, John A.

2010-01-01

Plague causes periodic epizootics that decimate populations of prairie dogs (PDs) (Cynomys), but the means by which the causative bacterium (Yersinia pestis) persists between epizootics are poorly understood. Plague epizootics in PDs might arise as the result of introductions of Y. pestis from sources outside PD colonies. However, it remains possible that plague persists in PDs during interepizootic periods and is transmitted at low rates among highly susceptible individuals within and between their colonies. If this is true, application of vector control to reduce flea numbers might reduce mortality among PDs. To test whether vector control enhances PD survival in the absence of obvious plague epizootics, we reduced the numbers of fleas (vectors for Y. pestis) 96–98% (1 month posttreatment) on 15 areas involving three species of PDs (Cynomys leucurus, Cynomys parvidens in Utah, and Cynomys ludovicianus in Montana) during 2000–2004 using deltamethrin dust delivered into burrows as a pulicide. Even during years without epizootic plague, PD survival rates at dusted sites were 31–45% higher for adults and 2–34% higher for juveniles compared to survival rates at nondusted sites. Y. pestis was cultured from 49 of the 851 flea pools tested (6882 total fleas) and antibodies against Y. pestis were identified in serum samples from 40 of 2631 PDs. Although other explanations are possible, including transmission of other potentially fatal pathogens by fleas, ticks, or other ectoparasites, our results suggest that plague might be maintained indefinitely in PD populations in the absence of free epizootics and widespread mortality among these animals. If PDs and their fleas support enzootic cycles of plague transmission, there would be important implications for the conservation of these animals and other species.

Infectious disease prevalence in a feral cat population on Prince Edward Island, Canada

Science.gov (United States)

Stojanovic, Vladimir; Foley, Peter

2011-01-01

Ninety-six feral cats from Prince Edward Island were used to determine the prevalence of selected infectious agents. The prevalence rates were 5.2% for feline immunodeficiency virus, 3.1% for feline leukemia virus, 3.1% for Mycoplasma haemofelis, 8.4% for Candidatus Mycoplasma haemominutum, 2.1% for Bartonella spp. and 29.8% for exposure to Toxoplasma gondii. Oocysts of T. gondii were detected in 1.3% of the fecal samples that were collected. Gender and retroviral status of the cats were significantly correlated with hemoplasma infections. Use of a flea comb showed that 9.6% of the cats had fleas; however, flea infestation was not associated with any of the infectious agents. PMID:22379197

77 FR 31844 - Notice of Intent to Suspend Certain Pesticide Registrations

Science.gov (United States)

2012-05-30

... range of stakeholders including environmental, human health, farm worker and agricultural advocates; the...-1 Bio-Groom Flea & Tick 5/21/12 1,2,3 a, b, c BioDerm Lab. Shampoo for Dogs & Cats. Brazos... Pyrethrins 15297-14 Bio-Groom Flea & Tick 5/21/12 1,2,3 a, b, c BioDerm Lab. Pyrethrin Dip Conc. For Dogs...

76 FR 12563 - Oral Dosage Form New Animal Drugs; Spinosad and Milbemycin Oxime

Science.gov (United States)

2011-03-08

... spinosad and milbemycin oxime in dogs for the treatment and prevention of flea infestations and for the... and milbemycin oxime) Chewable Tablets in dogs for the treatment and prevention of flea infestations... Friday. Under section 512(c)(2)(F)(ii) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 360b(c)(2...

Paltry past-precipitation: Predisposing prairie dogs to plague?

Science.gov (United States)

Eads, David; Biggins, Dean E.

2017-01-01

The plague bacterium Yersinia pestis was introduced to California in 1900 and spread rapidly as a sylvatic disease of mammalian hosts and flea vectors, invading the Great Plains in the United States by the 1930s to 1940s. In grassland ecosystems, plague causes periodic, devastating epizootics in colonies of black-tailed prairie dogs (Cynomys ludovicianus), sciurid rodents that create and maintain subterranean burrows. In doing so, plague inhibits prairie dogs from functioning as keystone species of grassland communities. The rate at which fleas transmit Y. pestis is thought to increase when fleas are abundant. Flea densities can increase during droughts when vegetative production is reduced and herbivorous prairie dogs are malnourished and have weakened defenses against fleas. Epizootics of plague have erupted frequently in prairie dogs during years in which precipitation was plentiful, and the accompanying cool temperatures might have facilitated the rate at which fleas transmitted Y. pestis. Together these observations evoke the hypothesis that transitions from dry-to-wet years provide conditions for plague epizootics in prairie dogs. Using generalized linear models, we analyzed a 24-year dataset on the occurrence of plague epizootics in 42 colonies of prairie dogs from Colorado, USA, 1982–2005. Of the 33 epizootics observed, 52% erupted during years with increased precipitation in summer. For the years with increased summer precipitation, if precipitation in the prior growing season declined from the maximum of 502 mm to the minimum of 200 mm, the prevalence of plague epizootics was predicted to increase 3-fold. Thus, reduced precipitation may have predisposed prairie dogs to plague epizootics when moisture returned. Biologists sometimes assume dry conditions are detrimental for plague. However, 48% of epizootics occurred during years in which precipitation was scarce in summer. In some cases, an increased abundance of fleas during dry years might

Serological and PCR investigation of Yersinia pestis in potential reservoir hosts from a plague outbreak focus in Zambia.

Science.gov (United States)

Nyirenda, S S; Hang'ombe, B M; Mulenga, E; Kilonzo, B S

2017-07-28

Plague is a bacterial zoonotic disease, caused by Yersinia pestis. Rodents are the natural hosts with fleas as the vehicle of disease transmission. Domestic and wild dogs and cats have also been identified as possible disease hosts. In Zambia, plague outbreaks have been reported in the Southern and Eastern regions in the last 20 years. Based on these observations, Y. pestis could possibly be endemically present in the area. To substantiate such possibility, sera samples were collected from rodents, shrews, dogs and cats for detection of antibodies against Fraction 1 gene (Fra1) of Y. pestis while organs from rodents and shrews, and fleas from both dogs and rodents were collected to investigate plasminogen activator gene (pla gene) of Y. pestis using ELISA and PCR respectively. A total of 369 blood samples were collected from domestic carnivores, shrews and domestic and peri-domestic rodents while 199 organs were collected from the rodents and shrews. Blood samples were tested for antibodies against Fra1 antigen using ELISA and 3% (5/165) (95% CI 0.99-6.93%) dogs were positive while all cats were negative. Of 199 sera from rodents and shrews, 12.6% (95% CI 8.30-17.98%) were positive for antibodies against Fra1 using anti-rat IgG secondary antibody while using anti-mouse IgG secondary antibody, 17.6% (95% CI 12.57-23.60%) were positive. PCR was run on the organs and 2.5% (95% CI 0.82-5.77%) were positive for plasminogen activator gene of Y. pestis and the amplicons were sequenced and showed 99% identity with Y. pestis reference sequences. All 82 fleas collected from animals subjected to PCR, were negative for pla gene. The specific rat-flea and dog-flea indices were 0.19 and 0.27 respectively, which were lower than the level required to enhance chances of the disease outbreak. We concluded that plague was still endemic in the area and the disease may infect human beings if contact is enhanced between reservoir hosts and flea vectors. The lower specific rodent-flea

Pesquisa da infecção natural por Yersinia pestis, em pulicídeos provenientes de focos pestosos do nordeste do Brasil

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Darci Pascoal Brasil

1989-12-01

Full Text Available Foram avaliados três processos de acondicionamento e transporte de pulgas, objetivando análise bacteriológica para isolamento da Yersinia pestis. As três abordagens testadas foram: pulgas vivas em tubos de ensaio com tiras dobradas de papel de filtro; pulgas em solução salina; macerados de pulgas em meio de Cary-Blair. Os dois últimos métodos foram quase iguais e superiores ao primeiro. Foram analisadas pelas três técnicas, um total de 29.512 "pools" de pulicideos provenientes de focos de peste do Nordeste do Brasil no período de 1966 a 1982. Deste total, 236 (0,80% dos "pools" foram positivos por cultura e/ou inoculação em animais sensíveis.Three different containment transport processes of fleas were evaluated as an approach to the bacteriologic isolation of Yersinia pestis. The three methods employed were: live fleas in glass tubes containing pieces of wrapped filter paper; dead fleas in saline solution; and maceratedfleas in Cary-Blair culture medium. The two latter methods were almost equal and superior to the first method. A total of 29512 flea pools, from plague foci in Northeast Brazil collected during 1966 to 1982 were evaluated by the three methods. Among these samples, 236 (0.80% flea pools were positive with regard to bacteriological cultivation and/or infection of susceptible animals.

Phylogenetic heritability of geographic range size in haematophagous ectoparasites: time of divergence and variation among continents.

Science.gov (United States)

Krasnov, Boris R; Shenbrot, Georgy I; van der Mescht, Luther; Warburton, Elizabeth M; Khokhlova, Irina S

2018-04-12

To understand existence, patterns and mechanisms behind phylogenetic heritability in the geographic range size (GRS) of parasites, we measured phylogenetic signal (PS) in the sizes of both regional (within a region) and continental (within a continent) geographic ranges of fleas in five regions. We asked whether (a) GRS is phylogenetically heritable and (b) the manifestation of PS varies between regions. We also asked whether geographic variation in PS reflects the effects of the environment's spatiotemporal stability (e.g. glaciation disrupting geographic ranges) or is associated with time since divergence (accumulation differences among species over time). Support for the former hypothesis would be indicated by stronger PS in southern than in northern regions, whereas support for the latter hypothesis would be shown by stronger PS in regions with a large proportion of species belonging to the derived lineages than in regions with a large proportion of species belonging to the basal lineages. We detected significant PS in both regional and continental GRSs of fleas from Canada and in continental GRS of fleas from Mongolia. No PS was found in the GRS of fleas from Australia and Southern Africa. Venezuelan fleas demonstrated significant PS in regional GRS only. Local Indicators of Phylogenetic Association detected significant local positive autocorrelations of GRS in some clades even in regions in which PS has not been detected across the entire phylogeny. This was mainly characteristic of younger taxa.

[Advance to the research of the climate factor effect on the distribution of plague].

Science.gov (United States)

Zhang, A P; Wei, R J; Xiong, H M; Wang, Z Y

2016-05-01

Plague is an anthropozoonotic disease caused by the Yersinia pestis ,which developed by many factors including local climate factors. In recent years, more and more studies on the effects of climate on plague were conducted. According to the researches, climate factors (mainly the rainfall and temperature) affected the development and distribution of plague by influencing the abundance of plague host animals and fleas index. The climate also affected the epidemic dynamics and the scope of plague. There were significant differences existing in the influence of climate on the palgue developed in the north and south China. In the two different plague epidemic systems, the solitary Daurian ground squirrel-flea-plague and the social Mongolian gerbil-flea-plague, the obvious population differences existed among the responses of the host animal to the climate changes. Although the internal relationship between the rainfall, the flea index, the density of rodents and the plague supported the nutritional cascade hypothesis, it can not prove that there is a clear causality between the occurrence of plague and rainfall. So the influence of climate factors on plague distribution can only be used for early forecasting and warning of the plague.

Observations on the endemicity of plague in Karatu and Ngorongoro, northern Tanzania.

Science.gov (United States)

Kilonzo, B S; Mbise, T J; Mwalimu, D C; Kindamba, L

2006-01-01

Commensal and field rodents and wild small carnivores were live-trapped in five villages of Karatu district and one settlement in the Ngorongoro Conservation Area in Ngorongoro district in Tanzania. Blood samples were taken and serologically tested for plague, using the Blocking ELISA technique. Some domestic dogs and cats in the Karatu villages were aseptically bled and similarly tested for plague. Fleas were collected from the examined animals and from randomly selected residential houses. A total of 241 rodents, 1 Crocidura spp, 43 dogs, 12 cats and 4 slender mongooses were involved in the survey. Of the rodents, 14.5% were infested with fleas, which comprised of Xenopsylla brasiliensis (45.8%) and Dinopsyllus lypusus (54.2%), with an overall population density of 0.2 fleas/animal. Thirty one (72.1%) of the dogs were infested with fleas, all of which were Ctenocephalides spp. Thirty five (63.3%) houses were infested with fleas whose population was composed of Ctenocephalides spp, Pulex irritans, Tunga penetrans and Echinophaga gallinacea. Infected rodents were found in all the villages while the infected dog was found at Rhotia-Kati. Nineteen (11%) of the rodents and one (2%) dog harboured specific plague antibodies. It was broadly concluded that sylvatic plague was endemic in Karatu district and Ngorongoro Conservation Area and that outbreaks of the disease can occur in the area any time if and when relevant conditions become favourable. Prompt application of appropriate preventive and control measures and survey for substantiating the status in the Lake Manyara National Park, which is adjacent to some of the infected villages, are recommended.

Human bubonic plague transmitted by a domestic cat scratch.

Science.gov (United States)

Weniger, B G; Warren, A J; Forseth, V; Shipps, G W; Creelman, T; Gorton, J; Barnes, A M

1984-02-17

Bubonic plague was transmitted to a 10-year-old girl in Oregon by a scratch wound inflicted by a domestic cat. The cat probably was infected by contact with infected wild rodents or their fleas. Yersinia pestis was identified in Diamanus montanus fleas collected from an abandoned burrow near the patient's home. Domestic cats may infect humans with Y pestis by inoculation from a scratch.

Deux nouveaux Ctenophthalmus (Insecta : Siphonaptera : Ctenophthalmidae de Tanzanie

Directory of Open Access Journals (Sweden)

Laudisoit A.

2007-06-01

Full Text Available Lors d’une étude épidémiologique du foyer pesteux de Lushoto, quelques puces rares ou nouvelles ont été collectées. Nous décrivons ici l’une d’entre elles, Ctenophthalmus (Ethioctenophthalmus teucqae n. sp. L’examen de spécimens de comparaison déposés au National History Museum (Londres, nous permet d’en créer une sous-espèce, C. (E. teucqae shumeensis n. ssp.

Why Sex?

DEFF Research Database (Denmark)

Nielsen, Rasmus

2006-01-01

It is assumed that most organisms have sex because the resulting genetic recombination allows Darwinian selection to work better. It is now shown that in water fleas, recombination does lead to fewer deleterious mutations.......It is assumed that most organisms have sex because the resulting genetic recombination allows Darwinian selection to work better. It is now shown that in water fleas, recombination does lead to fewer deleterious mutations....

Human Dipylidiasis: A Case Report of Dipylidium caninum Infection from Karimnagar

OpenAIRE

KV Ramana; Sanjeev D Rao; Ratna Rao; SK Mohanty; CG Wilson

2011-01-01

Dipylidium caninum also refered to as the double-pored tapeworm is a cyclophyllidean cestode that commonly infects dogs and cats. Mammals act as definite hosts with intermediate hosts being dog and cat flea, the Ctenocephalides canis and Ctenocephalides catis respectively. The dog lice, Trichodectes canis and human flea (Pulex irritans) also transmit Dipylidium caninum infection. Infants and young children are at high risk of acquiring infection. Majority of the infections are due to close as...

Infestasi Pinjal dan Infeksi Dipylidium Caninum Linnaeus pada Kucing Liar di Lingkungan Kampus Institut Pertanian Bogor, Kecamatan Dramaga

OpenAIRE

Bashofi, Aulia Syifak; Soviana, Susi; Ridwan, Yusuf

2015-01-01

This study was conducted to investigate flea infestation and Dipylidium caninum (Linnaeus 1758) infection on stray cat on Bogor Agricultural University Dramaga. Thirty stray cats were collected from various places around on Bogor Agricultural University Dramaga. The stray cats that showed clinical signs of pruritus and alopecia were collected purposively. The whole body was powdered by gamexan powder, after that the fleas were collected by manual and examined microscopically. The totals of 30...

3D Restoration Microscopy Improves Quantification of Enzyme-Labeled Fluorescence-Based Single-Cell Phosphatase Activity in Plankton

OpenAIRE

Diaz-de-Quijano, Daniel; Palacios, Pilar; Hornák, Karel; Felip, Marisol

2014-01-01

The ELF or fluorescence-labeled enzyme activity (FLEA) technique is a culture-independent single-cell tool for assessing plankton enzyme activity in close-to-in situ conditions. We demonstrate that single-cell FLEA quantifications based on two-dimensional (2D) image analysis were biased by up to one order of magnitude relative to deconvolved 3D. This was basically attributed to out-of-focus light, and partially to object size. Nevertheless, if sufficient cells were measured (25-40 cells), bia...

[Epidemics and risk factors of plague in Junggar Basin, Xinjiang Uygur Autonomous Region, 2007-2016].

Science.gov (United States)

Zhang, Y J; Wang, C; Luo, T; Guo, R; Meng, W W

2017-10-10

Objective: To explore the epidemic situation of animal plague in Junggar Basin natural plague foci. Methods: Data on epidemics of plague and on population involved, as well as results on antibodies and pathogens, were analyzed. Samples on animals and vectors were collected from 18 counties in Junggar Basin plague natural foci between 2007 and 2016. Results: The density of Rhombomys (R.) opimus was temporally fluctuant, from 2.1/hm(2) to 22.6/hm(2) respectively. However, the spatial distribution appeared asymmetrical, with the highest seen in Kelamayi and Wumuqi-midong counties, as 14.2/hm(2) and 13.0/hm(2) respectively. Rates of capture on nocturnal rodents were from 4.2 % to 10.1 % , with the highest rate as 10.1 % in 2014. Meriones meridianus appeared the dominant species in the nocturnal community of rodents, which accounted for 81.9 % . Regarding the spatial and temporal distributions, rates of R. opimus with fleas appeared fluctuant, with an average rate as 90.7 % and the average total flea index was 10.44. In flea community of R. opimus , Xenopsylla (X.) skrjabini was found the dominant species, popular in distribution and accounted for 47.8 % . The average rate of nocturnal rodents with flea was 20.2 % , with total flea index as 1.20 and the dominant fleas were X. conformis conformis and Nosopsyllus laeviceps . A total of 13 species with 9 087 serum samples from rodents were detected as having Y. pestis antibody by IHA, with 617 positive samples. Of them, the positive rate of having R. opimus appeared the highest (9.4 % ), followed by D. sagitta (1.1 % ). Spatially, two clustered areas were found, with one in the eastern Junggar Basin from Changji to Mulei county, with the antibody positive rates of R. opimus as 14.3 % . The other one was in the central area of Junggar Basin, including Kelamayi, Shawan and Wusu counties, with the antibody positive rate as 13.6 % . The prevalence of plague on R. opimus was fluctuant, with the lowest seen in 2008, with the

Gastrointestinal Helminths and Ectoparasites in the Stray Cats (Felidae: Felis catus) of Ahar Municipality, Northwestern Iran

Science.gov (United States)

YAKHCHALI, Mohammad; HAJIPOUR, Nasser; MALEKZADEH-VIAYEH, Reza; ESMAEILNEJAD, Bijan; NEMATI-HARAVANI, Taher; FATHOLLAHZADEH, Mohammad; JAFARI, Rasool

2017-01-01

Background: The stray cats are considered as the sources of emerging humans and domestic livestock pathogens and the zoonoses of public health importance. The present study was aimed to elucidate intestinal helminth infections and infestation with ectoparasites of the stray cats of Ahar City, northwestern Iran. Methods: Totally, 51 stray cats were randomly trapped from different parts of the city between Mar and Nov 2013. The cats were assessed for ectoparasites by hair brushing, skin scraping, acetate tape preparation and othic swabs. They were euthanized and inspected for helminths infection. Results: Overall prevalence of helminths and flea were 44/51 (86.3%) and 31/51 (60.78%), respectively. The infection rates were significantly different among different age groups (PDipylidium caninum (29.41%), T. hydatigena (19.6%)) were identified. The predominant infectious helminths in all the infected cats were T. cati (86.3% with egg per gram of feces 27.75±9). Of the 270 collected fleas, two species of Ctenocephalides felis (80%) and C. canis (20%) were notably frequent in the cats aged 2-3-year-old. The average number of fleas per each infected cat was recorded as 5.29, with no incidence of cross-infection. Conclusion: The results indicated the high rate of helminths infections and flea infestation in the urban stray cats of which Toxocara cati and Ctenocephalides felis may play important roles as zoonotic agents in the region. PMID:28761492

Small-Scale Die-Offs in Woodrats Support Long-Term Maintenance of Plague in the U.S. Southwest.

Science.gov (United States)

Kosoy, Michael; Reynolds, Pamela; Bai, Ying; Sheff, Kelly; Enscore, Russell E; Montenieri, John; Ettestad, Paul; Gage, Kenneth

2017-09-01

Our longitudinal study of plague dynamics was conducted in north-central New Mexico to identify which species in the community were infected with plague, to determine the spatial and temporal patterns of the dynamics of plague epizootics, and to describe the dynamics of Yersinia pestis infection within individual hosts. A total of 3156 fleas collected from 535 small mammals of 8 species were tested for Y. pestis DNA. Nine fleas collected from six southern plains woodrats (Neotoma micropus) and from one rock squirrel (Otospermophilus variegatus) were positive for the pla gene of Y. pestis. None of 127 fleas collected from 17 woodrat nests was positive. Hemagglutinating antibodies to the Y. pestis-specific F1 antigen were detected in 11 rodents of 6 species. All parts of the investigated area were subjected to local disappearance of woodrats. Despite the active die-offs, some woodrats always were present within the relatively limited endemic territory and apparently were never exposed to plague. Our observations suggest that small-scale die-offs in woodrats can support maintenance of plague in the active U.S. Southwestern focus.

Tungiasis in the United States: a travel souvenir.

Science.gov (United States)

Hager, Jon; Jacobs, Aleda; Orengo, Ida F; Rosen, Ted

2008-12-15

Tungiasis is a cutaneous infestation caused by the burrowing flea, Tunga penetrans. This infection typically results in the development of one or more wart-like fibrous papulonodules. The causative flea is endogenous to Central and South America, sub-Sarahan Africa and portions of India; consequently, tungiasis is rarely reported in North America. However, because of increasing air travel to and from endemic areas due to business and pleasure, it is imperative that this entity remain in the differential diagnosis when evaluating clinically suggestive lesions in a patient who also has a history of recent travel. We report a case of tungiasis in a 24-year-old Caucasian woman who presented with 7-week history of a non-healing, eroded nodule on the medial aspect of her left great toe. Significant history included travel to Tanzania during three months immediately prior to presentation. Following the presumptive clinical diagnosis of tungiasis, surgical removal of the flea and its contents was performed and the base of the lesion was curetted, without complication. The specimen was sent for histopathologic correlation which confirmed the diagnosis.

Canine and feline vector-borne diseases in Italy: current situation and perspectives

Directory of Open Access Journals (Sweden)

Dantas-Torres Filipe

2010-01-01

Full Text Available Abstract In Italy, dogs and cats are at risk of becoming infected by different vector-borne pathogens, including protozoa, bacteria, and helminths. Ticks, fleas, phlebotomine sand flies, and mosquitoes are recognized vectors of pathogens affecting cats and dogs, some of which (e.g., Anaplasma phagocytophilum, Borrelia burgdorferi, Dipylidium caninum, Leishmania infantum, Dirofilaria immitis, and Dirofilaria repens are of zoonotic concern. Recent studies have highlighted the potential of fleas as vectors of pathogens of zoonotic relevance (e.g., Rickettsia felis in this country. While some arthropod vectors (e.g., ticks and fleas are present in certain Italian regions throughout the year, others (e.g., phlebotomine sand flies are most active during the summer season. Accordingly, control strategies, such as those relying on the systematic use of acaricides and insecticides, should be planned on the basis of the ecology of both vectors and pathogens in different geographical areas in order to improve their effectiveness in reducing the risk of infection by vector-borne pathogens. This article reviews the current situation and perspectives of canine and feline vector-borne diseases in Italy.

Plague: Infections of Companion Animals and Opportunities for Intervention

Directory of Open Access Journals (Sweden)

Petra C.F. Oyston

2011-06-01

Full Text Available Plague is a zoonotic disease, normally circulating in rodent populations, transmitted to humans most commonly through the bite of an infected flea vector. Secondary infection of the lungs results in generation of infectious aerosols, which pose a significant hazard to close contacts. In enzootic areas, plague infections have been reported in owners and veterinarians who come into contact with infected pets. Dogs are relatively resistant, but can import infected fleas into the home. Cats are acutely susceptible, and can present a direct hazard to health. Reducing roaming and hunting behaviours, combined with flea control measures go some way to reducing the risk to humans. Various vaccine formulations have been developed which may be suitable to protect companion animals from contracting plague, and thus preventing onward transmission to man. Since transmission has resulted in a number of fatal cases of plague, the vaccination of domestic animals such as cats would seem a low cost strategy for reducing the risk of infection by this serious disease in enzootic regions.

Molecular Evidence of Different Rickettsia Species in Villeta, Colombia.

Science.gov (United States)

Faccini-Martínez, Álvaro A; Ramírez-Hernández, Alejandro; Forero-Becerra, Elkin; Cortés-Vecino, Jesús A; Escandón, Patricia; Rodas, Juan D; Palomar, Ana M; Portillo, Aránzazu; Oteo, José A; Hidalgo, Marylin

2016-02-01

The aim of this work was to detect and identify Rickettsia species in ticks collected in rural areas of Villeta, Colombia. Tick specimens were collected from domestic animals and walls of houses in five rural villages of Villeta town and from humans in Naranjal village (same town). Moreover, a flea collected from the same area was also processed. DNA was extracted and tested by conventional, semi-nested, and nested PCR reactions targeting rickettsial genes. In the ticks collected from humans from Naranjal village, a nymph of Amblyomma cajennense sensu lato was amplified using primers for ompA and sequenced (100% identity with "Candidatus Rickettsia amblyommii"). Last, three amplicons from the Ctenocephalides felis flea, corresponding to gltA, ompB, and 16S rRNA genes, showed high identity with R. felis (98.5%, 97.3%, and 99.2%, respectively) and "Candidatus Rickettsia asemboensis" (99.7% and 100%, respectively). To our knowledge, these results correspond to the first molecular detection in Colombia of "Candidatus Rickettsia amblyommii" and "Ca. Rickettsia asemboensis" in fleas.

Shell-vial culture and real-time PCR applied to Rickettsia typhi and Rickettsia felis detection.

Science.gov (United States)

Segura, Ferran; Pons, Immaculada; Pla, Júlia; Nogueras, María-Mercedes

2015-11-01

Murine typhus is a zoonosis transmitted by fleas, whose etiological agent is Rickettsia typhi. Rickettsia felis infection can produces similar symptoms. Both are intracellular microorganisms. Therefore, their diagnosis is difficult and their infections can be misdiagnosed. Early diagnosis prevents severity and inappropriate treatment regimens. Serology can't be applied during the early stages of infection because it requires seroconversion. Shell-vial (SV) culture assay is a powerful tool to detect Rickettsia. The aim of the study was to optimize SV using a real-time PCR as monitoring method. Moreover, the study analyzes which antibiotics are useful to isolate these microorganisms from fleas avoiding contamination by other bacteria. For the first purpose, SVs were inoculated with each microorganism. They were incubated at different temperatures and monitored by real-time PCR and classical methods (Gimenez staining and indirect immunofluorescence assay). R. typhi grew at all temperatures. R. felis grew at 28 and 32 °C. Real-time PCR was more sensitive than classical methods and it detected microorganisms much earlier. Besides, the assay sensitivity was improved by increasing the number of SV. For the second purpose, microorganisms and fleas were incubated and monitored in different concentrations of antibiotics. Gentamicin, sufamethoxazole, trimethoprim were useful for R. typhi isolation. Gentamicin, streptomycin, penicillin, and amphotericin B were useful for R. felis isolation. Finally, the optimized conditions were used to isolate R. felis from fleas collected at a veterinary clinic. R. felis was isolated at 28 and 32 °C. However, successful establishment of cultures were not possible probably due to sub-optimal conditions of samples.

Gastrointestinal Helminths and Ectoparasites in the Stray Cats (Felidae: Felis catus of Ahar Municipality, Northwestern Iran

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Mohammad YAKHCHALI

2017-06-01

Full Text Available Background: The stray cats are considered as the sources of emerging humans and domestic livestock pathogens and the zoonoses of public health importance. The present study was aimed to elucidate intestinal helminth infections and infestation with ectoparasites of the stray cats of Ahar City, northwestern Iran.Methods: Totally, 51 stray cats were randomly trapped from different parts of the city between Mar and Nov 2013. The cats were assessed for ectoparasites by hair brushing, skin scraping, acetate tape preparation and othic swabs. They were euthanized and inspected for helminths infection.Results: Overall prevalence of helminths and flea were 44/51 (86.3% and 31/51 (60.78%, respectively. The infection rates were significantly different among different age groups (P<0.05. Of the 282 isolated helminths, three species of nematodes (Toxocara cati (86.3%, T. leonina (11.77%, Ancylostoma tubaeforme (5.9% and four species of cestodes (Taenia taeniaeformis (64.7%, Mesocestoides lineatus (49.02%, Dipylidium caninum (29.41%, T. hydatigena (19.6% were identified. The predominant infectious helminths in all the infected cats were T. cati (86.3% with egg per gram of feces 27.75±9. Of the 270 collected fleas, two species of Ctenocephalides felis (80% and C. canis (20% were notably frequent in the cats aged 2-3-year-old. The average number of fleas per each infected cat was recorded as 5.29, with no incidence of cross-infection.Conclusion: The results indicated the high rate of helminths infections and flea infestation in the urban stray cats of which Toxocara cati and Ctenocephalides felis may play important roles as zoonotic agents in the region.

Beta-diversity of ectoparasites at two spatial scales: nested hierarchy, geography and habitat type.

Science.gov (United States)

Warburton, Elizabeth M; van der Mescht, Luther; Stanko, Michal; Vinarski, Maxim V; Korallo-Vinarskaya, Natalia P; Khokhlova, Irina S; Krasnov, Boris R

2017-06-01

Beta-diversity of biological communities can be decomposed into (a) dissimilarity of communities among units of finer scale within units of broader scale and (b) dissimilarity of communities among units of broader scale. We investigated compositional, phylogenetic/taxonomic and functional beta-diversity of compound communities of fleas and gamasid mites parasitic on small Palearctic mammals in a nested hierarchy at two spatial scales: (a) continental scale (across the Palearctic) and (b) regional scale (across sites within Slovakia). At each scale, we analyzed beta-diversity among smaller units within larger units and among larger units with partitioning based on either geography or ecology. We asked (a) whether compositional, phylogenetic/taxonomic and functional dissimilarities of flea and mite assemblages are scale dependent; (b) how geographical (partitioning of sites according to geographic position) or ecological (partitioning of sites according to habitat type) characteristics affect phylogenetic/taxonomic and functional components of dissimilarity of ectoparasite assemblages and (c) whether assemblages of fleas and gamasid mites differ in their degree of dissimilarity, all else being equal. We found that compositional, phylogenetic/taxonomic, or functional beta-diversity was greater on a continental rather than a regional scale. Compositional and phylogenetic/taxonomic components of beta-diversity were greater among larger units than among smaller units within larger units, whereas functional beta-diversity did not exhibit any consistent trend regarding site partitioning. Geographic partitioning resulted in higher values of beta-diversity of ectoparasites than ecological partitioning. Compositional and phylogenetic components of beta-diversity were higher in fleas than mites but the opposite was true for functional beta-diversity in some, but not all, traits.

[Yersinia pestis and plague - an update].

Science.gov (United States)

Stock, Ingo

2014-12-01

The plague of man is a severe, systemic bacterial infectious disease. Without antibacterial therapy, the disease is associated with a high case fatality rate, ranging from 40% (bubonic plague) to nearly 100% (septicemic and pneumonic plague). The disease is caused by Yersinia pestis, a non-motile, gram-negative, facultative anaerobic bacterium belonging to the family of Enterobacteriaceae. In nature, Y. pestis has been found in several rodent species and some other small animals such as shrews. Within its reservoir host, Y. pestis circulates via flea bites. Transmission of Y. pestis to humans occurs by the bite of rat fleas, other flea vectors or by non vectorial routes, e. g., handling infected animals or consumption of contaminated food. Human-to-human transmission of the pathogen occurs primarily through aerosol droplets. Compared to the days when plague was a pandemic scourge, the disease is now relatively rare and limited to some rural areas of Africa. During the last ten years, however, plague outbreaks have been registered repea- tedly in some African regions. For treatment of plague, streptomycin is still considered the drug of choice. Chloramphenicol, doxycycline, gentamicin and ciprofloxacin are also promising drugs. Recombinant vaccines against plague are in clinical development.

Molecular, serological and epidemiological observations after a suspected outbreak of plague in Nyimba, eastern Zambia.

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Nyirenda, Stanley S; Hang'ombe, Bernard M; Kilonzo, Bukheti S; Kabeta, Mathews N; Cornellius, Mundia; Sinkala, Yona

2017-01-01

Plague is a re-emerging zoonotic disease caused by the bacterium Yersinia pestis. The disease has caused periodic global devastation since the first outbreak in the 6th century. Two months after a suspected plague outbreak in Nyimba district, samples were collected from 94 livestock (goats and pigs), 25 rodents, 6 shrews and 33 fleas. Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) techniques were used to investigate the presence of Y. pestis, which showed that 16.0% (4/25) of rodents, 16.7% (1/6) of shrews (Crocidura spp) and 6.0% (5/83) of goats were positive for IgG antibodies against Fraction 1 antigen of Y. pestis. Plasminogen activator (Pla) gene (DNA) of Y. pestis was detected in five pools containing 36.4% (12/33) fleas collected from pigs (n = 4), goats (n = 5) and rodents (n = 3). The detection of Pla gene in fleas and IgG antibodies against Fraction1 antigen in rodents, shrews and goats suggest that Y. pestis had been present in the study area in the recent past. © The Author(s) 2016.

Tunga penetrans and further parasites in the giant anteater (Myrmecophaga tridactyla) from Minas Gerais, Brazil.

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Frank, Raphael; Melaun, Christian; Martins, Maria Marlene; Santos, André Luiz Quagliatto; Heukelbach, Jörg; Klimpel, Sven

2012-11-01

The Brazilian savannah-like area, the Cerrado region, covers large areas of the country and provides a habitat for a multitude of different animal species. The giant anteater (Myrmecophaga tridactyla) is geographically widespread and one of the typical inhabitants of the Cerrado. They are listed as vulnerable by the International Union for Conservation of Nature and Natural Resources. A population loss of at least 30 % over the past 10 years has been estimated based on local extinctions, habitat loss and deaths caused by fires, roadkills and hunting. Little is known about ecological and in particular parasitic conditions of this highly specialised insectivore species. During September and November 2010 we examined three roadkilled giant anteater for the presence of metazoan ecto- and endoparasites. Besides the cestode species Oochoristica tetragonocephala and the tick species Amblyomma nodosum, we found for the first time the flea Tunga penetrans. Beside morphological flea species identification, we compared a fragment of the 16S rRNA gene of eggs, a molecular method utilised for the first time in this combination. The identification of T. penetrans in M. tridactyla represents a new host record and expands the host and distribution range of the zoonotic flea species.

Prevalence of ectoparasites in dogs of Shimoga, Karnataka.

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Krishna Murthy, C M; Ananda, K J; Adeppa, J

2017-03-01

A study was carried out to ascertain the status of ecto-parasites infesting dogs of Shimoga region. A total of 120 dogs with the history of skin problems presented to the local hospitals and local pet clinics of Shimoga region were screened for different ecto-parasites. The ticks, fleas and lice were collected, processed and identified. The skin scrapings were also collected from the affected dogs and processed for identification of mites. Out of 120 dogs examined, 59 (49.1 %) had harboured ecto-parasites. Among 59 infested pet dogs, 22 (37.28 %) positive for Fleas, 18 (30.5 %) for ticks, 09 (15.2 %) for Lice, 07 (11.8 %) for Sarcoptic mange and 03 (5.0 %) were for Demodectic mange conditions. The two species of fleas were identified as Ctenocephalides canis 13 (59 %) and Ctenocephalides felis 9 (41 %). The ticks and lice species were identified as Riphicephalus sanguineus and Trichodectus canis respectively. The mite species infecting dogs were identified as Sarcoptes scabeii and Demodex canis based on the morphological character. The Prevalence of ectoparasites was more in stray and adults dogs compared to pet dogs and puppies respectively.

Human activity spaces and plague risks in three contrasting landscapes in Lushoto District, Tanzania.

Science.gov (United States)

Hieronimo, Proches; Gulinck, Hubert; Kimaro, Didas N; Mulungu, Loth S; Kihupi, Nganga I; Msanya, Balthazar M; Leirs, Herwig; Deckers, Jozef A

2014-07-01

Since 1980 plague has been a human threat in the Western Usambara Mountains in Tanzania. However, the spatial-temporal pattern of plague occurrence remains poorly understood. The main objective of this study was to gain understanding of human activity patterns in relation to spatial distribution of fleas in Lushoto District. Data were collected in three landscapes differing in plague incidence. Field survey coupled with Geographic Information System (GIS) and physical sample collections were used to collect data in wet (April to June 2012) and dry (August to October 2012) seasons. Data analysis was done using GIS, one-way ANOVA and nonparametric statistical tools. The degree of spatial co-occurrence of potential disease vectors (fleas) and humans in Lushoto focus differs significantly (p ≤ 0.05) among the selected landscapes, and in both seasons. This trend gives a coarse indication of the possible association of the plague outbreaks and the human frequencies of contacting environments with fleas. The study suggests that plague surveillance and control programmes at landscape scale should consider the existence of plague vector contagion risk gradient from high to low incidence landscapes due to human presence and intensity of activities.

78 FR 11879 - Product Cancellation Order for Certain Pesticide Registrations

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2013-02-20

... Phenothrin/ Jet Stream. Tetramethrin 028293-00293 Unicorn 30 Day Flea Permethrin & Tick Treatment. 028293-00357 Unicorn 45% Permethrin Permethrin Fly & Tick Insecticide. 028293-00358 Unicorn 45% Permethrin...

Rickettsia infection in five areas of the state of São Paulo, Brazil

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Maurício C Horta

2007-11-01

Full Text Available This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi, and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting fleas, whereas Rickettsia bellii was the only agent infecting ticks, but no animal or human blood was shown to contain rickettsial DNA. Testing animal and human sera by indirect immunofluorescence assay against four rickettsia antigens (R. rickettsii, R. parkeri, R. felis, and R. bellii, some opossum, dog, horse, and human sera reacted to R. rickettsii with titers at least four-fold higher than to the other three rickettsial antigens. These sera were considered to have a predominant antibody response to R. rickettsii. Using the same criteria, opossum, dog, and horse sera showed predominant antibody response to R. parkeri or a very closely related genotype. Our serological results suggest that both R. rickettsii and R. parkeri infected animals and/or humans in the studied areas.

Evaluation of Yersinia pestis transmission pathways for sylvatic plague in prairie dog populations in the western U.S.

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Richgels, Katherine L. D.; Russell, Robin E.; Bron, Gebbiena; Rocke, Tonie E.

2016-01-01

Sylvatic plague, caused by the bacterium Yersinia pestis, is periodically responsible for large die-offs in rodent populations that can spillover and cause human mortalities. In the western US, prairie dog populations experience nearly 100% mortality during plague outbreaks, suggesting that multiple transmission pathways combine to amplify plague dynamics. Several alternate pathways in addition to flea vectors have been proposed, such as transmission via direct contact with bodily fluids or inhalation of infectious droplets, consumption of carcasses, and environmental sources of plague bacteria, such as contaminated soil. However, evidence supporting the ability of these proposed alternate pathways to trigger large-scale epizootics remains elusive. Here we present a short review of potential plague transmission pathways and use an ordinary differential equation model to assess the contribution of each pathway to resulting plague dynamics in black-tailed prairie dogs (Cynomys ludovicianus) and their fleas (Oropsylla hirsuta). Using our model, we found little evidence to suggest that soil contamination was capable of producing plague epizootics in prairie dogs. However, in the absence of flea transmission, direct transmission, i.e., contact with bodily fluids or inhalation of infectious droplets, could produce enzootic dynamics, and transmission via contact with or consumption of carcasses could produce epizootics. This suggests that these pathways warrant further investigation.

In vitro efficacy of essential oils and extracts of Schinus molle L. against Ctenocephalides felis felis.

Science.gov (United States)

Batista, Lilian C De S O; Cid, Yara P; De Almeida, Ana Paula; Prudêncio, Edlene R; Riger, Cristiano J; De Souza, Marco A A; Coumendouros, Katherine; Chaves, Douglas S A

2016-04-01

Extracts and essential oils from plants are important natural sources of pesticides. These compounds are considered an alternative to control ectoparasites of veterinary importance. Schinus molle, an endemic species of Brazil, produces a high level of essential oil and several other compounds. The aim of this work was to determinate the chemical composition of extracts and essential oils of S. molle and further to evaluate the activity against eggs and adults of Ctenocephalides felis felis, a predominant flea that infests dogs and cats in Brazil. In an in vitro assay, the non-polar (n-hexane) extract showed 100% efficacy (800 µg cm(-2); LD50 = 524·80 µg cm(-2)) at 24 and 48 h. Its major compound was lupenone (50·25%). Essential oils from fruits and leaves were evaluated, and had 100% efficacy against adult fleas at 800 µg cm(-2) (LD50 = 353·95 µg cm(-2)) and at 50 µg cm(-2) (LD50 = 12·02 µg cm(-2)), respectively. On the other hand, the essential oil from fruits and leaves was not active against flea eggs. This is the first study that reports the insecticidal effects of essential oils and extracts obtained from Schinus molle against Ctenocephalides felis felis.

Desenvolvimento dos fungos Metarhizium anisopliae (Metschnikoff, 1879 Sorokin, 1883 E Beauveria bassiana (Balsamo Vuillemin, 1912 sobre Ctenocephalides felis felis (Bouché, 1835 Development of the fungi Metarhizium anisopliae (Metschnikoff, 1879 Sorokin, 1883 and Beauveria bassiana (Balsamo Vuillemin, 1912 on the Ctenophephalides felis felis (Bouché, 1835

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Denise R. De Melo

2007-09-01

Full Text Available A pulga Ctenocephalides felis felis é um parasita causador dermatites alérgicas e também pode transmitir diversos agentes etiológicos aos animais domésticos e aos homens. O objetivo deste trabalho foi verificar o desenvolvimento do fungo sobre a cutícula da pulga, através da microscopia eletrônica de varredura. Os isolados fúngicos testados foram o Metarhizium anisopliae 959 e Beauveria bassiana 986, ambos na concentração 10(8 conídios/ml. Após a exposição dos isolados fúngicos no período de duas, 15, 26 e 96 horas , o material foi processado para a microscopia eletrônica de varredura. Com a obtenção das micrografias, pode-se observar que com 2 horas após exposição aos fungos, os conídios estavam aderidos por toda a cutícula, situando-se preferencialmente nas membranas intersegmentais do abdome. Com 15 horas observou-se a formação do tubo de germinação e a cabeça do apressório e após 26 horas foi possível observar as ramificações e o engrossamento das hifas sobre a cutícula das pulgas. Os resultados indicam que os fungos testados foram capazes de se desenvolver sobre a cutícula de C. f. felis.The flea Ctenocephalides felis felis is a parasite that causes allergic dermatitis and also may transmit etiologic agents to domestic animals and humans. This study investigated by scanning electron microscopy the development of entomopathogenic fungi on flea cuticle. Fleas were exposed to conidia (10(8 ml-1 of Metarhizium anisopliae (isolate 959 or Beauveria bassiana (isolate 986. Following standard protocols for electron microscopy, the specimens were prepared 2, 15, 26 and 96 h after infection. The micrography revealed that 2 h after fungus exposure, conidia attachments encompassed the entire flea cuticle, especially on abdominal intersegmental membranes. The emergence of germ tubes and appressoria formation occurred at 15 h, thickening and branching of hyphae on the flea cuticle was noted at 26 h. Therefore, both of

76 FR 11460 - Product Cancellation Order for Certain Pesticide Registrations

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2011-03-02

... with Preemergent Weed Control. 044446-00053 Kill A Bug II Insect Spray.. Phenothrin 044446-00066 Aero Roach & Ant Insecticide Phenothrin 045188-00002 Harrison Flea and Tick Piperonyl butoxide Shampoo for...

Genetic and sexual separation between insect resistant and susceptible Barbarea vulgaris plants in Denmark

DEFF Research Database (Denmark)

Toneatto, Fiorello; Nielsen, Jens Kvist; Ørgaard, Marian

2010-01-01

of these interactions, we tested how genetically divergent resistant and susceptible plants are, using microsatellite markers. To test whether they are reproductively fully compatible, resistant and susceptible plants were grown intermixed in an outdoor experiment, and the paternity of open-pollinated offspring......Co-evolution between herbivores and plants is believed to be one of the processes creating Earth’s biodiversity. However, it is difficult to disentangle to what extent diversification is really driven by herbivores or by other historical-geographical processes like allopatric isolation....... In the cruciferous plant Barbarea vulgaris, some Danish individuals are resistant to herbivory by flea beetles (Phyllotreta nemorum), whereas others are not. The flea beetles are, in parallel, either resistant or susceptible to the plants defenses. To understand the historical-evolutionary framework...

75 FR 4072 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

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2010-01-26

... 000004-00315 Bonide Liquid Rotenone Pyrethrins Pyrethrins Spray Rotenone 000004-00337 Insect Fog... Piperonyl Butoxide MGK-264 013799-00017 Four Paws Flea and PBO Tick Soap Pyrethrins MGK 264 [[Page 4075...

75 FR 48669 - Product Cancellation Order for Certain Pesticide Registrations

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2010-08-11

... Registration No. Product Name Chemical Name 000004-00315 Bonide Liquid Pyrethrins Rotenone Rotenone Pyrethrins... Paws Flea and Piperonyl butoxide Tick Soap Pyrethrins MGK 264 013799-00022 Four Paws Mite and Piperonyl...

Epizoic fauna of Plecotus mexicanus (Chiroptera: Vespertilionidae) in Tlaxcala, Mexico.

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Morales-Malacara, J B; López, R

1990-07-01

Four hundred nineteen arthropod ectoparasites were taken from Plecotus mexicanus (Vespertilionidae) collected in the state of Tlaxcala, Mexico: the insects Trichobius corynorhini Cockerell (Diptera: Streblidae) and Myodopsylla collinsi Kohls (Siphonaptera: Ischnopsyllidae) and the mites Macronyssus longisetosus (Furman) and M. unidens Radovsky (Macronyssidae), Spinturnix sp. (Spinturnicidae), Pteracarus elegans Dusbádek & Wilson and Acanthophthirius (Myotimyobia) sp. (Myobiidae), and Whartonia glenni Brennan (Trombiculidae). P. mexicanus is reported in the state of Tlaxcala for the first time. This is the first survey of ectoparasites of this bat, and all parasite associations with P. mexicanus are new host records as well as new range records for Tlaxcala. This is the first report from Mexico; it records a major southern extension of the ranges of M. longisetosus, M. unidens, and P. elegans. The genus Acanthophthirius is also reported in Mexico for the first time.

Identification of risk factors for plague in the West Nile Region of Uganda.

Science.gov (United States)

Eisen, Rebecca J; MacMillan, Katherine; Atiku, Linda A; Mpanga, Joseph T; Zielinski-Gutierrez, Emily; Graham, Christine B; Boegler, Karen A; Enscore, Russell E; Gage, Kenneth L

2014-06-01

Plague is an often fatal, primarily flea-borne rodent-associated zoonosis caused by Yersinia pestis. We sought to identify risk factors for plague by comparing villages with and without a history of human plague cases within a model-defined plague focus in the West Nile Region of Uganda. Although rat (Rattus rattus) abundance was similar inside huts within case and control villages, contact rates between rats and humans (as measured by reported rat bites) and host-seeking flea loads were higher in case villages. In addition, compared with persons in control villages, persons in case villages more often reported sleeping on reed or straw mats, storing food in huts where persons sleep, owning dogs and allowing them into huts where persons sleep, storing garbage inside or near huts, and cooking in huts where persons sleep. Compared with persons in case villages, persons in control villages more commonly reported replacing thatch roofing, and growing coffee, tomatoes, onions, and melons in agricultural plots adjacent to their homesteads. Rodent and flea control practices, knowledge of plague, distance to clinics, and most care-seeking practices were similar between persons in case villages and persons in control villages. Our findings reinforce existing plague prevention recommendations and point to potentially advantageous local interventions. © The American Society of Tropical Medicine and Hygiene.

Direct evidence of Rickettsia typhi infection in Rhipicephalus sanguineus ticks and their canine hosts

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Karla Dzul-Rosado

2017-06-01

Full Text Available Murine typhus is a rickettsiosis caused by Rickettsia typhi, whose transmission is carried out by rat fleas in urban settlements as classically known, but it also has been related to cat fleas in a sub-urban alternative cycle that has been suggested by recent reports. These studies remarks that in addition to rats, other animals like cats, opossums and dogs could be implied in the transmission of Rickettsia typhi as infected fleas obtained from serologically positive animals have been detected in samples from endemic areas. In Mexico, the higher number of murine typhus cases have been detected in the Yucatan peninsula, which includes a great southeastern region of Mexico that shows ecologic characteristics similar to the sub-urban alternative cycle recently described in Texas and California at the United States. To find out which are the particular ecologic characteristics of murine typhus transmission in this region, we analyzed blood and Rhipicephalus sanguineus ticks obtained from domestic dogs by molecular approaches, demonstrating that both samples were infected by Rickettsia typhi. Following this, we obtained isolates that were analyzed by genetic sequencing to corroborate this infection in 100% of the analyzed samples. This evidence suggests for the first time that ticks and dogs could be actively participating in the transmission of murine typhus, in a role that requires further studies for its precise description.

Age at weaning, immunocompetence and ectoparasite performance in a precocial desert rodent

Czech Academy of Sciences Publication Activity Database

Dlugosz, E. M.; Goüy de Bellocq, Joëlle; Khokhlova, I. S.; Degen, A. A.; Pinshow, B.; Krasnov, B. R.

2014-01-01

Roč. 217, č. 17 (2014), s. 3078-3084 ISSN 0022-0949 Institutional support: RVO:68081766 Keywords : Fleas * PHA response * Weaning * Spiny mouse Subject RIV: EG - Zoology Impact factor: 2.897, year: 2014

Insect bites and stings

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... widow spider bite; Brown recluse bite; Flea bite; Honey bee or hornet sting; Lice bites; Mite bite; ... Saunders; 2016:chap 359. Otten EJ. Venomous animal injuries. In: Walls RM, Hockberger RS, Gausche-Hill M, ...

Drug: D07613 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available D07613 Drug Carbaryl (BAN); Carbaril; Flea and tick powder [veterinary] (TN) ... C12H...11NO2 D07613.gif ... Same as: C07491 ... carbamate insecticide cholinesterase inhibitor veterinary medicine ...

The synergistic action of imidacloprid and flumethrin and their release kinetics from collars applied for ectoparasite control in dogs and cats

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Stanneck Dorothee

2012-04-01

Full Text Available Abstract Background The control of tick and flea burdens in dogs and cats has become essential to the control of important and emerging vector borne diseases, some of which are zoonoses. Flea worry and flea bite hypersensitivity are additionally a significant disease entity in dogs and cats. Owner compliance in maintaining the pressure of control measures has been shown to be poor. For these reasons efforts are continuously being made to develop ectoparasiticides and application methods that are safe, effective and easy to apply for pet owners. A new polymer matrix collar has recently been developed which is registered for 8 months use in cats and dogs. The basic properties of this collar have been investigated in several in vitro and in vivo studies. Methods The effects of imidacloprid, flumethrin and the combination were evaluated in vitro by means of whole cell voltage clamp measurement experiments conducted on isolated neuron cells from Spodoptera frugiperda. The in vitro efficacy of the two compounds and the combination against three species of ticks and their life stages and fleas were evaluated in a dry surface glass vial assay. The kinetics of the compounds over time in the collar were evaluated by the change in mass of the collar and measurement of the surface concentrations and concentrations of the actives in the collar matrix by HPLC. Hair clipped from collar treated dogs and cats, collected at various time points, was used to assess the acaricidal efficacy of the actives ex vivo. Results An in vitro isolated insect nerve model demonstrated the synergistic neurotoxic effects of the pyrethroid flumethrin and the neonicotinoid imidacloprid. An in vitro glass vial efficacy and mortality study against various life stages of the ticks Ixodes ricinus, Rhipicephalus sanguineus and Dermacentor reticulatus and against the flea (Ctenocephalides felis demonstrated that the combination of these products was highly effective against these

The synergistic action of imidacloprid and flumethrin and their release kinetics from collars applied for ectoparasite control in dogs and cats

Science.gov (United States)

2012-01-01

Background The control of tick and flea burdens in dogs and cats has become essential to the control of important and emerging vector borne diseases, some of which are zoonoses. Flea worry and flea bite hypersensitivity are additionally a significant disease entity in dogs and cats. Owner compliance in maintaining the pressure of control measures has been shown to be poor. For these reasons efforts are continuously being made to develop ectoparasiticides and application methods that are safe, effective and easy to apply for pet owners. A new polymer matrix collar has recently been developed which is registered for 8 months use in cats and dogs. The basic properties of this collar have been investigated in several in vitro and in vivo studies. Methods The effects of imidacloprid, flumethrin and the combination were evaluated in vitro by means of whole cell voltage clamp measurement experiments conducted on isolated neuron cells from Spodoptera frugiperda. The in vitro efficacy of the two compounds and the combination against three species of ticks and their life stages and fleas were evaluated in a dry surface glass vial assay. The kinetics of the compounds over time in the collar were evaluated by the change in mass of the collar and measurement of the surface concentrations and concentrations of the actives in the collar matrix by HPLC. Hair clipped from collar treated dogs and cats, collected at various time points, was used to assess the acaricidal efficacy of the actives ex vivo. Results An in vitro isolated insect nerve model demonstrated the synergistic neurotoxic effects of the pyrethroid flumethrin and the neonicotinoid imidacloprid. An in vitro glass vial efficacy and mortality study against various life stages of the ticks Ixodes ricinus, Rhipicephalus sanguineus and Dermacentor reticulatus and against the flea (Ctenocephalides felis) demonstrated that the combination of these products was highly effective against these parasites. The release kinetics of

Investigation of and Response to 2 Plague Cases, Yosemite National Park, California, USA, 2015.

Science.gov (United States)

Danforth, Mary; Novak, Mark; Petersen, Jeannine; Mead, Paul; Kingry, Luke; Weinburke, Matthew; Buttke, Danielle; Hacker, Gregory; Tucker, James; Niemela, Michael; Jackson, Bryan; Padgett, Kerry; Liebman, Kelly; Vugia, Duc; Kramer, Vicki

2016-12-01

In August 2015, plague was diagnosed for 2 persons who had visited Yosemite National Park in California, USA. One case was septicemic and the other bubonic. Subsequent environmental investigation identified probable locations of exposure for each patient and evidence of epizootic plague in other areas of the park. Transmission of Yersinia pestis was detected by testing rodent serum, fleas, and rodent carcasses. The environmental investigation and whole-genome multilocus sequence typing of Y. pestis isolates from the patients and environmental samples indicated that the patients had been exposed in different locations and that at least 2 distinct strains of Y. pestis were circulating among vector-host populations in the area. Public education efforts and insecticide applications in select areas to control rodent fleas probably reduced the risk for plague transmission to park visitors and staff.

Integrating Gigabit ethernet cameras into EPICS at Diamond light source

International Nuclear Information System (INIS)

Cobb, T.

2012-01-01

At Diamond Light Source a range of cameras are used to provide images for diagnostic purposes in both the accelerator and photo beamlines. The accelerator and existing beamlines use Point Grey Flea and Flea2 Firewire cameras. We have selected Gigabit Ethernet cameras supporting GigE Vision for our new photon beamlines. GigE Vision is an interface standard for high speed Ethernet cameras which encourages inter-operability between manufacturers. This paper describes the challenges encountered while integrating GigE Vision cameras from a range of vendors into EPICS. GigE Vision cameras appear to be more reliable than the Firewire cameras, and the simple cabling makes much easier to move the cameras to different positions. Upcoming power over Ethernet versions of the cameras will reduce the number of cables still further

Infection in ecosystems: Data, Models and Effects

NARCIS (Netherlands)

Selakovic, S.

2016-01-01

Infectious agents are ubiquitous in nature. They can be broadly distinguished into microparasites (viruses, bacteria, fungi, protozoa), macroparasites (nematodes, trematodes and cestodes), ectoparasites (fleas and ticks), parasitic castrators and parasitoids. Although these types of infectious

Insect Bites and Stings

Science.gov (United States)

Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, ...

[Dipylidium caninum infection in an infant].

Science.gov (United States)

Tsumura, Naoki; Koga, Hiroyasu; Hidaka, Hidenobu; Mukai, Fumiko; Ikenaga, Masaaki; Otsu, Yasushi; Masunaga, Kenji; Nagai, Kensuke; Yoneda, Yutaka; Fukuma, Toshihide; Ishimoto, Koji

2007-07-01

Dipylidium caninum, the dog tapeworm, is a common intestinal cestode of domestic dogs and cats, but few cases have been reported of human infection by this parasite in Japan. We repot a case of D. caninum infection in a 17 month-old girl, who sometimes had symptoms of abdominal pain, diarrhea, and dysphoria at night. Her mother noted the appearance of small white worms in her stool, and she was seen by a local pediatrician. Despite antiparasitic therapy wiht pyrantel pamoate, the problem persisted and was eventually referred for further workup to Kurume University Hospital. The diagnosis was made by microscopic examination of the excreted proglottids, which contained characteristic egg capsules. She was successfully treated with a singledose of praziquantel and four adult parasites were recovered. The longest intact worm was 32cm. Her family had household pets (a dog and a cat). The pets were seen by the local veterinary and both were evidenced D. caninum. Humans, primarily children, become infected when they accidentally ingest fleas. Parents usually find proglottids as multiple white objects, often described as cucumber, melon, or pumpkin seeds, in stool, diapers, or on the perineum. Most general practitioners and pediatricians may treat children with enterobiasis (pinworm) infection, and in case the treatment fails, other parasite infection should be considered such as this worm. A history of dog or cat pets, fleas, and flea bites may be important clues to diagnosis. Pets found to be infected should also be treated.

Characterization of Tunga penetrans antigens in selected epidemic areas in Murang'a county in Kenya.

Directory of Open Access Journals (Sweden)

Jamleck N Mwangi

2015-03-01

Full Text Available Tunga penetrans are fleas that cause tungiasis, a condition characterized by high transmission rate due to poor housing conditions, social neglect and inadequate health care in economically disadvantaged communities in developing countries. This study therefore aimed at characterizing jiggers antigens to identify immunodominant ones to help understand immunological behavior of the parasite that would otherwise be important in future control of the parasite. Samples were gravid fleas and blood samples from infested individuals in Kahuro and Murang'a East district in Murang'a County. Freeze and thaw was used to extract soluble proteins from the fleas. Ouchterlony Double immunodiffusion was used to assess antigen-antibody reactions between extracted soluble protein and the serum from immunized rats, Rattus norvegicus prior to analysis of human sera. These results were comparable to results of immunoelectrphoresis. Jigger protein isolates were analyzed in Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis technique (SDS-PAGE, against Pharmacia standard protein markers. Further analysis of jigger antigens against pooled human sera from infested victims in Western blot revealed three immunodominant antigens. Using simple regression analysis molecular weights of the three immunodominant antigens were estimated as 51.795, 23.395 and 15.38 kDa respectively. These results are important since they would help understand immunological behavior of the parasites. This would help to create basis for designing and improving approaches against jiggers such as development of immune prophylaxis to complement social science approaches that is mainly concerned with maintenance of high standards of hygiene.

PREDICTORS OF TRYPANOSOMA LEWISI IN RATTUS NORVEGICUS FROM DURBAN, SOUTH AFRICA.

Science.gov (United States)

Archer, Colleen Edith; Schoeman, M Corrie; Appleton, Christopher Charles; Mukaratirwa, Samson; Hope, Karen J; Matthews, Glenda Beverly

2018-03-16

This study investigated associations between Trypanosoma lewisi; Xenopsylla cheopis, a common cyclical vector of T. lewisi; Polyplax spinulosa, a reported mechanical vector; and Laelaps ecidnina and L. lamborni, two rodent mites of Rattus norvegicus in Durban. Three hundred and seventy nine R. norvegicus were live-trapped at 48 sites in 4 locality types of Durban during a one year period. Rats were euthanized, cardiac blood was taken to check for hemoparasites and ectoparasites were removed for identification. Parasite species richness was higher in pups (2.11) and juveniles (1.02) than adults (0.87). Most rats in the study harbored 1 or 2 of the 5 parasites examined. Rats with trypanosomes and fleas were more prevalent in the city center and harbor, and juveniles were most affected. Rats with lice were more prevalent in informal settlements and urban/peri-urban areas and pups had the highest infestations. There was a significant positive association between rats with fleas and trypanosomes and a negative association between rats with lice and trypanosomes. Location and rat age were significant predictors of T. lewisi, X. cheopis and P. spinulosa. Mites showed no strong associations with trypanosomes. Ectoparasite associations are possibly habitat and life-cycle related. We conclude that Durban's city center, which offers rats harborage, an unsanitary environment and availability of food, is a high transmission area for fleas and trypanosomes, and consequently, a potential public health risk.

Investigation of hypereosinophilia and potential treatments.

Science.gov (United States)

Lilliehöök, Inger; Tvedten, Harold

2003-11-01

Hypereosinophilia is excessive eosinophilia and has been defined in dogs and cats as eosinophils greater than 5 x 10(9)/L (> 5000/microL). Canine breeds with a predisposition to higher eosinophil counts or certain eosinophilic diseases include the Rottweiler, German Shepard, Siberian Husky, Alaskan Malamute, and Cavalier King Charles Spaniel. Two of the more common causes of canine hypereosinophilia are pulmonary infiltrates with eosinophils (PIE) and gastrointestinal disease. The highest eosinophil counts are expected in dogs with pneumonia or PIE. The most common cause of eosinophilia in cats is flea allergy. The greatest eosinophilia occurs in cats with flea allergy, feline asthma, and eosinophilic granuloma. Innovative recent treatments for human patients with asthma have been successful in reducing eosinophil numbers but have had a confusing and disappointing lack of reducing symptoms. The role of eosinophils in many eosinophilic diseases remains a mystery.

Rickettsial pathogens and arthropod vectors of medical and veterinary significance on Kwajalein Atoll and Wake Island

Directory of Open Access Journals (Sweden)

Durden, L.

2012-05-01

Full Text Available Modern surveys of ectoparasites and potential vector-borne pathogens in the Republic of the Marshall Islands and Wake Island are poorly documented. We report on field surveys of ectoparasites from 2010 with collections from dogs, cats, and rats. Five ectoparasites were identified: the cat flea Ctenocephalides felis, a sucking louse Hoplopleura pacifica, the mites Laelaps nuttalli and Radfordia ensifera, and the brown dog tickRhipicephalus sanguineus. Ectoparasites were screened for rickettsial pathogens. DNA from Anaplasma platys, a Coxiella symbiont of Rhipicephalus sanguineus, anda Rickettsia sp. were identified by PCR and DNA sequencing from ticks and fleas on Kwajalein Atoll. An unidentified spotted fever group Rickettsia was detected in a pool of Laelaps nuttalli and Hoplopleura pacifica from Wake Island. The records of Hoplopleura pacifica, Laelaps nuttalli, and Radfordia ensifera and the pathogens are new for Kwajalein Atoll and Wake Island.

Investigation of and Response to 2 Plague Cases, Yosemite National Park, California, USA, 2015

Science.gov (United States)

Danforth, Mary; Novak, Mark; Petersen, Jeannine; Mead, Paul; Kingry, Luke; Weinburke, Matthew; Buttke, Danielle; Hacker, Gregory; Tucker, James; Niemela, Michael; Jackson, Bryan; Padgett, Kerry; Liebman, Kelly; Vugia, Duc

2016-01-01

In August 2015, plague was diagnosed for 2 persons who had visited Yosemite National Park in California, USA. One case was septicemic and the other bubonic. Subsequent environmental investigation identified probable locations of exposure for each patient and evidence of epizootic plague in other areas of the park. Transmission of Yersinia pestis was detected by testing rodent serum, fleas, and rodent carcasses. The environmental investigation and whole-genome multilocus sequence typing of Y. pestis isolates from the patients and environmental samples indicated that the patients had been exposed in different locations and that at least 2 distinct strains of Y. pestis were circulating among vector–host populations in the area. Public education efforts and insecticide applications in select areas to control rodent fleas probably reduced the risk for plague transmission to park visitors and staff. PMID:27870634

The 2nd international veterinary poultry congress of Iran

African Journals Online (AJOL)

ehsan

2012-07-24

Jul 24, 2012 ... infected with the fleas (C. colombae) and lice (M. gallinae) as seen by the clinical manifestation of allergic urticarial ... Pigeons live side by side with human and other ... that all pigeons were infested with P. canariensis a blood.

Bio-insecticides and mating disruption in cranberries

Science.gov (United States)

Surveys of native entomopathogenic nematodes in Wisconsin have produced a new bio-insecticide involving two particular nematode species (Oscheius onirici and Heterorhabditis georgiana). In field studies, these nematodes have shown high virulence against flea beetles; in the laboratory, these nematod...

SPESIES TIKUS, CECURUT DAN PINJAL YANG DITEMUKAN DI PASAR KOTA BANJARNEGARA, KABUPATEN BANJARNEGARA TAHUN 2013

Directory of Open Access Journals (Sweden)

Dina Supriyati

2014-01-01

Full Text Available ABSTRACTRats harm to human life, both in terms of economics and health. Rats transmitted disease, ectoparasites andendoparasites. Many potential sites where rat found in high enough quantities, one of those sites is a traditionalmarket. The purpose of this study was to know the presence of rats and fleas in the market town Banjarnegara,Banjarnegara District. This research is a descriptive study using survey methods. Research design using crosssectionalapproach. Rats data obtained by trapping rats using a live trap. Population was rats living in marketsBanjarnegara, Banjarnegara. The sample was rats that were caught using bait traps roasted coconut andcucumber. The collected data were analyzed descriptively. Result showed that 33 rats had been caught during thestudy. The most abundant species was Rattus tanezumi (84.85%, while the least is Rattus norvegicus (3.03%. Asmuch 20 (60.61% were male higger than female rat as much as 13 rats (39.39%. Rats in the market stalls(77,42% greater than the outside market stall (22,58%. The trap succes were 8.25% with the successful captureof the highest rats on day 2 (4.5%. While the success of trapping rats (trap success based on the location of thearrest shows that in the market stalls (6.5% greater than the outside market stall (1.75%. Number of fleas thatinfest species caught as many as 67 tails. Species of fleas that infest rats identified as Xenopsylla cheopis. Commonflea index as much 2,03 upper than standard. Control of rats and fleas (Xenopsylla cheopis was needed.Key words: trap success, rats, fleasABSTRAKTikus merugikan bagi kehidupan manusia, baik dari sisi ekonomi maupun kesehatan. Tikus membawa kumanpenyakit, ektoparasit dan endoparasit. Pasar tradisional merupakan tempat potensial ditemukan tikus dalamjumlah cukup tinggi. Tujuan penelitian untuk mengetahui keberadaan tikus, cecurut dan ektoparasit pinjal diPasar Kota Banjarnegara, Kabupaten Banjarnegara. Penelitian deskriptif dengan metode survei

Seasonal dynamics of three insect pests in the cabbage field in central Slovenia.

Science.gov (United States)

Trdan, Stanislav; Vidrih, Matej; Bobnar, Aleksander

2008-01-01

From the beginning of April until the beginning of November 2006, a seasonal dynamics of three harmful insect species--Swede midge (Contarinia nasturtii [Kieffer], Diptera, Cecidomyiidae), flea beetles (Phyllotreta spp., Coleoptera, Chrysomelidae), and diamondback moth (Plutella xylostella [L.], Lepidoptera, Plutellidae)--was investigated at the Laboratory Field of the Biotechnical Faculty in Ljubljana (Slovenia). The males were monitored with pheromone traps; the males of Swede midge were trapped with the traps of Swiss producer (Agroscope FAW, Wädenswill), while the adult flea beetles (trap type KLP+) and diamondback moths (trap type RAG) were trapped with the Hungarian traps (Plant Protection Institute, Hungarian Academy of Sciences). The pheromone capsules were changed in 4-week intervals, while the males were counted on about every 7th day. The first massive occurrence of diamondback moth (1.6 males/trap/day) was established in the second 10 days period of April, and the pest remained active until the 2nd 10 days period of September. The adults were the most numerous in the period between the end of May until the middle of June, but even then their number did not exceed three males caught per day. In the first 10 days period of May, the first adult flea beetles were recorded in the pheromone traps, while their notable number (0.8 males/trap/day) was stated in the third 10 days period of May. Absolutely the highest number of the beetles was recorded in the second (19 adults/trap/day) and in the third (25 adults/trap/day) 10 days of July, and the pest occurred until the beginning of October. The first massive occurrence of Swede midge (0.4 males/trap/day) was established in the second 10 days period of May, while the highest number of males (8/trap/day) were caught in the second 10 days period of July. In the third 10 days period of October, the last adults were found in the traps. Based on the results of monitoring of three cabbage insect pests we ascertained

Research projects lead by the USDA Cranberry Entomology Laboratory (CEL)

Science.gov (United States)

1. Newly discovered native nematode species represent bio-insecticides (grad student project) a. Problems being addressed: Issues over flea beetle control; unresolved questions over pesticide use during bloom. b. Discoveries: at least two native nematodes species new to science have been discovered ...

77 FR 42654 - Trifloxystrobin; Pesticide Tolerance

Science.gov (United States)

2012-07-20

... document ``Trifloxystrobin. Human Health Risk Assessment for a Section 3 Petition Proposing Increased... for trifloxystrobin in drinking water. These simulation models take into account data on the physical... garden pest control, indoor pest control, termiticides, and flea and tick control on pets...

Filmcoating the seed of cabbage (Brassica oleracea L. convar. Capitata L.) and cauliflower (Brassica oleracea L. var. Botrytis L.) with imidacloprid and spinosad to control insect pests

NARCIS (Netherlands)

Ester, A.; Putter, de H.; Bilsen, van J.G.P.M.

2003-01-01

Four field experiments were carried out between 1999 and 2001, to assess the protection against cabbage root fly larvae (Delia radicum), flea beetle (Phyllotreta nemorum and P. undulata), cabbage aphid (Brevicoryne brassicae) and caterpillars achieved in white cabbage and cauliflower crops by

75 FR 44954 - Product Cancellation Order for Certain Pesticide Registrations

Science.gov (United States)

2010-07-30

... Propachlor Flake Technical 028293-00125 Unicorn Permethrin Permethrin RTU Spray 028293-00147 Unicorn 14-day Pyrethrins Flea & Tick Spray Permethrin 028293-00148 Unicorn Permethrin Permethrin Pet Dip II 028293-00154 Unicorn Pertran Bioallethrin Aerosol Permethrin 028293-00155 Unicorn Crawling & Permethrin Flying Insect...

Letterman Army Institute of Research Annual Research Progress Report, FY 1981.

Science.gov (United States)

1981-10-01

five species of mosquitoes. These compounds were tested against sand flies ( Lutzomyia longipalpis), fleas (Xenopsylla cheopis ) and bugs (Rhodnius...BUESCHER, M.D., L.C. RUTLEDGE, R.A. WIRTZ, K.B. GLACKIN, and M.A. MOUSSA. Laboratory tests of repellents against Lutzomyia longipalpis (Diptera

A study of ectoparasites in wild rodents of the Jaz Murian area in the southeast of Iran

Directory of Open Access Journals (Sweden)

Asghar Khajeh

2017-07-01

Full Text Available Objective: To detect wild rodents ectoparasites in the southeast of Iran. Methods: In this survey, the wild rodents were trapped from 2014 to 2015. The captured rodents were checked for any ectoparasites. Results: In this study, 681 ectoparasites belonged to 6 species of flea, 2 species of lice, 1 species of mite and 2 species of hard tick were collected. The flea species were including, Xenopsylla gerbilli, Xenopsylla cheopis, Xenopsylla buxtoni, Xenopsylla conformis, Nosopsyllus medus and Amphipysylla spp., the lice species were including Hoplopleura spp. and Polyplax spp., the mite species was Ornithonyssus bacoti and tick species were Rhipicephalus spp. and Hyalomma spp. Conclusions: Among all ectoparasites, Hoplopleura spp. and Amphipysylla spp. had the high and low frequency infestation in rodents, respectively. Also among captured rodents, the highest ectoparasites infestation was found in Tatera indica and no ectoparasites in Apodemus witherbyi, Cricetelus migratorius, and Microtus mystacinus kermanesis.

Understanding the Persistence of Plague Foci in Madagascar

Science.gov (United States)

Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

2013-01-01

Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar. PMID:24244760

[Clinical symptomps, diagnosis and therapy of feline allergic dermatitis].

Science.gov (United States)

Favrot, C; Rostaher, A; Fischer, N

2014-07-01

Allergies are often suspected in cats and they are mainly hypersensitivity reactions against insect bites, food- or environmental allergens. Cats, with non flea induced atopic dermatitis, normally present with one oft he following reaction patterns: miliary dermatitis, eosinophilic dermatitis, selfinduced alopecia or head and neck excoriations. None of these reaction patterns is nevertheless pathognomonic for allergic dermatitis, therefore the diagnosis is based on the one hand on the exclusion of similar diseases on the other hand on the successful response on a certain therapy. Recently a study on the clinical presentation of cats with non flea induced atopic dermatitis was published. In this study certain criteria for diagnosing atopy in cats were proposed. For therapy of allergic cats cyclosporin, glucocorticoids, antihistamines, hypoallergenic diets and allergen specific immunotherapy are used. This article should provide a recent overview on the clinical symptoms, diagnosis and therapy of feline allergic dermatitis.

Wild and domestic animals likely involved in rickettsial endemic zones of Northwestern Colombia.

Science.gov (United States)

Londoño, Andrés F; Acevedo-Gutiérrez, Leidy Y; Marín, Diana; Contreras, Verónica; Díaz, Francisco J; Valbuena, Gustavo; Labruna, Marcelo B; Hidalgo, Marylin; Arboleda, Margarita; Mattar, Salim; Solari, Sergio; Rodas, Juan D

2017-10-01

Between 2006 and 2008, three outbreaks of human rickettsiosis occurred in Northwestern Colombia (municipalities of Necoclí, Los Córdobas and Turbo), with case fatality rates between 27% and 54%. The aim of this study was to determine previous exposure of wild and domestic animals to spotted fever group (SFG) rickettsiae through serological tests, to detect rickettsial evidence in their ectoparasites, and to analyze their possible role in the epidemiology of rickettsial diseases in this zone of the country. A cross-sectional association study was performed from 2010 to 2011. Blood and ectoparasite samples were collected from domestic animals and small mammals. A statistically significant association (panimals and the study zones was observed. A total of 2937 ticks, 672 fleas and 74 lice were collected and tested in pools by PCR. The minimum infection rate (MIR) of the positive pools was 5% in ticks, 4% in fleas, and 0% in lice. Phylogenetic analyses showed circulation of three 4.Rickettsia species: R. felis in fleas, and R. bellii and Rickettsia sp. strain Atlantic rainforest, both in Amblyomma ovale ticks. In conclusion, this study demonstrated the occurrence of SFG rickettsiae in domestic, synanthropic and wild animals, and suggests the use of equines and canines as good sentinels of infection, in the study zone. We speculate that a transmission cycle exist involving rodents in the areas where these outbreaks have occurred. Tomes' spiny rats (Proechimys semispinosus) and common opossums (Didelphis marsupialis) could be good candidates as amplifier hosts for SFG rickettsiae in enzootic/endemic zones. Copyright © 2017 Elsevier GmbH. All rights reserved.

Hedgehogs (Erinaceus europaeus as a Source of Ectoparasites in Urban-suburban Areas of Northwest of Iran

Directory of Open Access Journals (Sweden)

Nasser Hajipour

2015-10-01

Full Text Available Background: Hedgehogs are small, nocturnal mammals which become popular in the world and have important role in transmission of zoonotic agents. Thus, the present study aimed to survey ectoparasite infestation from April 2010 to December 2011 in urban and suburban parts of Urmia and Tabriz Cities, Northwest of Iran.Methods: A total number of 84 hedgehogs (40 females and 44 males were examined. They have been carefully inspected for ectoparasites and collected arthropods were stored in 70% ethanol solution. The identification of arthropods was carried out using morphological diagnostic keys.Results: The occurrence of ticks on hedgehogs was 23 (67.7% with Rhipicephalus turanicus in Urmia and 11 (22% as well as 1(2% with Rh. turanicus and Hyalomma anatolicum anatolicum in Tabriz, respectively. One flea species, Archaeopsylla erinacei, was found with prevalence of 19 (55.9% and 27 (54% in Urmia and Tabriz Cities, respectively. Prevalence of infestation with Rh. turanicus and A. erinacei were not different (P> 0.05 between sexes of hedgehogs in two study areas. Highest prevalence of tick and flea infestation was in June in Urmia, whereas it was observed in August in Tabriz. Both tick and flea parasitizing hedgehogs showed seasonal difference in prevalence (P< 0.05 in Urmia, but it was not detected in Tabriz (P> 0.05.Conclusion: The result showed the high occurrence of ectoparasites in hedgehog population and according to the zoonotic potential of these animals as vector of some agents further studies are needed to investigate in different parts of Iran.

Ecto- and endoparasites in remaining population of wild rabbit Oryctolagus cuniculus (L., 1758 in east Bohemia

Directory of Open Access Journals (Sweden)

Vladimír Bádr

2005-01-01

Full Text Available An investigation of ecto- and endoparasites of wild rabbit Oryctolagus cuniculus (L., 1758 was made during February and March 2004. Together five species of ectoparasites and seven species of endopara- sites was found in five specimens of host. Ectoparasites: acarids Leporacarus gibbus (Pagenstecher, 1862, Psoroptes cuniculi (Delafond, 1859, and Cheyletiella parasitivorax (Mégnin, 1878, flea Spilopsyllus cuniculi (Dale, 1878, and louse Haemodipsus ventricosus (Denny, 1842. Except of petechial haemorrhagies inside both earlobes of one rabbit neither hyperkeratosis nor scale with any degrees of hairlessness were detected. Higher incidence of flea Spilopsyllus cuniculi could be important for spreading of myxomatosis. In one rabbit abnormal damage of incisivi was found, which caused the highest documented incidence of acarids Cheyletiella parasitivorax (485 ex., fleas Spilopsyllus cuniculi (65 ex., and especially enormous amount of louse Haemodipsus ventricosus (1840 ex. This finding establish close relation between prevalence and counts of ectoparasites with health of host, because popu- lation of ectoparasites from different taxonomic groups are principally affected by effective hostęs cleanup. Handicapped hosts are not able to make clarify as effective as the healthy ones. Endoparasites: tapeworm Taenia pisiformis (Bloch, 1780 – larvae, nematods Passalurus ambiguus (Rudolphi, 1819 Rudolphi, 1845; Graphidium strigosum (Dujardin, 1845 Railliet and Henry, 1909, Trichostrongylus retortaeformis (Zeder, 1800 Loos, 1905 and protozoa Eimeria piriformis Kotlan & Pospesch, 1934; E. media Kessel, 1929, and E. perforans (Leuckart, 1879 Sluiter & Swellengrebel, 1912. All endoparasites were found in very low or middle intensity, which does not seem to be main cause of decreasing number of wild rabbits in monitored areas.

Preliminary validation of real-time PCR assays for the identification of Yersinia pestis (Authors' personal document)

NARCIS (Netherlands)

Tomaso, H.; Jacobs, D.; Eickhoff, M.; Scholz, H.C.; Dahouk, S.al; Kattar, M.M.; Reischl, U.; Plicka, H.; Strand Olsen, J.; Nikkari, S.; Matero, P.; Beuret, C.; Ciammaruconi, A.; Lista, F.; Gala, J.-L.; Broll, H.; Appel, B.; Sellek Cano, R.E.; Ybarra de Villavicencio, M.d.C.; Broekhuijsen, M.P.; Indra, A.; Petersen, R.; Neubauer, H.

2008-01-01

Background: Yersinia pestis (Y. pestis) is a zoonotic bacterium mainly circulating among rodents and their fleas. Transmission to humans can cause bubonic, pneumonic or septicemic plague with a high case-fatality rate. Therefore, rapid and reliable diagnostic tools are crucial. The objective of this

77 FR 66715 - Fluridone; Pesticide Tolerances for Emergency Exemptions

Science.gov (United States)

2012-11-07

...--Summary of Toxicological Doses and Endpoints for Fluridone for Use in Human Health Risk Assessment Point... account data on the physical, chemical, and fate/transport characteristics of fluridone. Further... pest control, termiticides, swimming in treated water, and flea and tick control on pets). Fluridone is...

77 FR 65827 - Trifloxystrobin; Pesticide Tolerances

Science.gov (United States)

2012-10-31

... document ``Trifloxystrobin. Human Health Risk Assessment for a Section 3 Petition Proposing Increased... trifloxystrobin in drinking water. These simulation models take into account data on the physical, chemical, and..., and flea and tick control on pets). Trifloxystrobin is currently registered for the following uses...

75 FR 8256 - Nicosulfuron; Pesticide Tolerances for Emergency Exemptions

Science.gov (United States)

2010-02-24

....gov in the July 14, 2009 document ``Nicosulfuron: Human Health Risk Assessment for Proposed Section 18... account data on the physical, chemical, and fate/transport characteristics of nicosulfuron. Further... garden pest control, indoor pest control, termiticides, and flea and tick control on pets). Nicosulfuron...

Evaluation of systemic insecticides mixed in rodenticide baits for plague vector control

DEFF Research Database (Denmark)

Larsen, Kim Søholt; Lodal, Jens

1997-01-01

Rodenticide baits containing systemic insecticides were evaluated in the laboratory for their palatability to the house rat Rattus rattus and for their toxicity against the oriental rat flea Xenopsylla cheopis - both animals are important Vectors of plague in Africa. The test bait and a non...

Effects of an anionic surfactant (FFD-6) on the energy and information flow between a primary producer (Scenedesmus obliquus) and a consumer (Daphnia magna)

NARCIS (Netherlands)

Lürling, M.; de Lange, H.J.; Peeters, E.T.H.M.

2011-01-01

The effects of a commercially available anionic surfactant solution (FFD-6) on growth and morphology of a common green alga (Scenedesmus obliquus) and on survival and clearance rates of the water flea Daphnia magna were studied. The surfactant-solution elicited a morphological response (formation of

75 FR 44247 - Product Cancellation Order for Certain Pesticide Registrations

Science.gov (United States)

2010-07-28

...-Rest AQ Pyrethrins, Piperonyl butoxide 067517-00045 Hard Hitter Permethrin Aerosol 067517-00049 Dog and... Permethrin 067517-00056 Flea And Insect Pyrethrins, Carpet Dust Piperonyl butoxide 067517-00057 Cat And Dog Pyrethrins, Pyrethrin Powder Piperonyl butoxide 067517-00061 Permethrin 10% Permethrin W.B. Multi- Purpose...

77 FR 72343 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

Science.gov (United States)

2012-12-05

.../ Esfenvalerate. 010807-00451 Bee, Wasp & Hornet Phenothrin/ Jet Stream. Tetramethrin. 028293-00293 Unicorn 30 Day Flea & Permethrin. Tick Treatment. 028293-00357 Unicorn 45% Permethrin. Permethrin Fly & Tick Insecticide. 028293-00358 Unicorn 45% Permethrin. Permethrin Flee & Tick Insecticide. 038167-00029 Mach 2 1.5G...

Genetic and geographic structure of an insect resistant and a susceptible type of Barbarea vulgaris in western Europe

DEFF Research Database (Denmark)

Hauser, Thure Pavlo; Toneatto, Fiorello; Nielsen, Jens Kvist

2012-01-01

allopatric isolation. The cruciferous plant Barbarea vulgaris ssp. arcuata occurs in Denmark in two types: one (G) is resistant to most genotypes of the flea beetle Phyllotreta nemorum, the other (P) is susceptible. The two types additionally differ in hairiness and glucosinolates, they are genetically...

Allergien durch Stiche und Bisse von Insekten und Spinnentieren

DEFF Research Database (Denmark)

Blank, S; Schiener, M; Ollert, M.

2016-01-01

Allergic reactions due to stings of Hymenoptera species, such as honeybees or yellow jackets, are well known as severe allergies with potentially fatal outcome. Much less common is that also bites of blood-sucking insects (mosquitos, horseflies, flies, bugs, lice and fleas) and arachnids (ticks...

Evaluation of cimi-shield knock-out bed bug eliminator against house fly (Musca domestica) adults.

Science.gov (United States)

Cimi-Shield Knock-Out (CSKO) Bed Bug Eliminator is a green treatment labeled for use against bed bugs, carpet beetles, ants, roaches, fleas, ticks, silverfish, millipedes and centipedes. The active ingredient is soybean oil. If CSKO is formulated according to label instructions and sprayed directly ...

Temporal and host-related variation in frequencies of genes that enable Phyllotreta nemorum to utilize a novel host plant, Barbarea vulgaris

NARCIS (Netherlands)

Nielsen, J.K.; Jong, de P.W.

2005-01-01

The flea beetle, Phyllotreta nemorum L. (Coleoptera: Chrysomelidae), is an intermediate specialist feeding on a small number of plants within the family Brassicaceae. The most commonly used host plant is Sinapis arvensis L., whereas the species is found more rarely on Cardaria draba (L.) Desv.,

The Importance of Systematics

Indian Academy of Sciences (India)

1999-02-18

Feb 18, 1999 ... Similarly, the work of Nathan Charles Rothschild, a taxonomic authority on flea species, was responsible for the discovery ... The use of genetic data for taxonomic purposes also brings systematics closer to realizing Darwin's desire that classification should reflect evolutionary relationships. Systematics is.

Environmental statistical modelling of mosquito vectors at different geographical scales

NARCIS (Netherlands)

Cianci, D.

2015-01-01

Vector-borne diseases are infections transmitted by the bite of infected arthropod vectors, such as mosquitoes, ticks, fleas, midges and flies. Vector-borne diseases pose an increasingly wider threat to global public health, both in terms of people affected and their geographical spread. Mosquitoes

Protect Yourself from Plague

Science.gov (United States)

... rodents. Plague can also infect humans and their pets. How do people get plague? • • Bites of infected fleas • • Touching or ... be treated successfully with antibiotics, but an infected person must be treated ... your pets 1. Eliminate nesting places for rodents around homes, ...

77 FR 26467 - Fluoxastrobin; Pesticide Tolerances

Science.gov (United States)

2012-05-04

... subgroups of consumers, including infants and children. The most recent human health risk assessment for... in drinking water. These simulation models take into account data on the physical, chemical, and fate... flea and tick control on pets). Fluoxastrobin is currently registered for the following uses that could...

Outbreaks of Rickettsia felis in Kenya and Senegal, 2010

Centers for Disease Control (CDC) Podcasts

This podcast describes the outbreak of Rickettsia felis in Kenya between August 2006 and June 2008, and in rural Senegal from November 2008 through July 2009. CDC infectious disease pathologist Dr. Chris Paddock discusses what researchers learned about this flea-borne disease and how to prevent infection.

76 FR 18895 - Hexythiazox; Pesticide Tolerances

Science.gov (United States)

2011-04-06

... lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets... children in the case of threshold effects to account for prenatal and postnatal toxicity and the... support the choice of a different factor. 2. Prenatal and postnatal sensitivity. The prenatal and...

77 FR 12727 - Trifloxystrobin; Pesticide Tolerances

Science.gov (United States)

2012-03-02

...-occupational, non-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets). Trifloxystrobin is currently registered for the following uses... of threshold effects to account for prenatal and postnatal toxicity and the completeness of the...

Opportunity to use native nematodes for pest control

Science.gov (United States)

We have surveyed wild cranberry bogs in WI and found three isolates of native nematodes. We have been testing these nematodes as potential biological control agents in for cranberry insect pests including sparganothis fruitworm and flea beetle. The nematodes seem to be effective at finding and killi...

Analysis of temperature-dependent changes in the metabolism of Yersinia pestis.

Science.gov (United States)

Navid, Ali; Almaas, Eivind

2008-03-01

The gram-negative bacterium Yersinia pestis is the aetiological agent of bubonic plague, a zoonotic infection that occurs through the bite of a flea. It has long been known that Y. pestis has different metabolic needs upon transition from the flea gut environment (26 C) to that of a mammalian host (37 C). To study this and other outstanding questions about metabolic function of Y. pestis, we used the available genomic, biochemical and physiological data to develop a constraint-based flux balance model of metabolism in the avirulent 91001 strain (biovar Mediaevalis) of this organism. Utilizing two sets of whole-genome DNA microarray expression data, we examined the system level changes that occur when Y. pestis acclimatizes to temperature shifts. Our results point to fundamental changes in its oxidative metabolism of sugars and use of amino acids, in particular that of arginine. This behavior is indicative of an inefficient metabolism that could be caused by adaptation to life in a nutrient rich environment.

A Human Case of Zoonotic Dog Tapeworm, Dipylidium caninum (Eucestoda: Dilepidiidae), in China.

Science.gov (United States)

Jiang, Peng; Zhang, Xi; Liu, Ruo Dan; Wang, Zhong Quan; Cui, Jing

2017-02-01

We described a human case of zoonotic dog tapeworm, Dipylidium caninum (Eucestoda: Dilepidiidae), rarely occurring in China. The mother of a 17 month-old boy noted the appearance of small white and active worms over a month period in her son's feces, but the boy was asymptomatic except mild diarrhea. We observed 3 tapeworm proglottids resembling cucumber seeds in his stool sample. Microscopically, each proglottid had 2 genital pores, 1 on each lateral edge, and numerous egg capsules in the uterus. The patient was successfully treated with a single oral dose of praziquantel. Adult worms were recovered in the diarrheic stool after praziquantel treatment and purgation. His family had household pet dogs for several years, and he might have acquired the infection by ingestion of infected fleas of his pet dogs. A history of dog or cat pets and flea bites may be important clues to diagnosis of D. caninum infection. The infected pets should also be treated.

Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

Science.gov (United States)

Miarinjara, Adélaïde; Boyer, Sébastien

2016-02-01

Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

Bacterial communities of disease vectors sampled across time, space, and species.

Science.gov (United States)

Jones, Ryan T; Knight, Rob; Martin, Andrew P

2010-02-01

A common strategy of pathogenic bacteria is to form close associations with parasitic insects that feed on animals and to use these insects as vectors for their own transmission. Pathogens interact closely with other coexisting bacteria within the insect, and interactions between co-occurring bacteria may influence the vector competency of the parasite. Interactions between particular lineages can be explored through measures of alpha-diversity. Furthermore, general patterns of bacterial community assembly can be explored through measures of beta-diversity. Here, we use pyrosequencing (n=115,924 16S rRNA gene sequences) to describe the bacterial communities of 230 prairie dog fleas sampled across space and time. We use these communinty characterizations to assess interactions between dominant community members and to explore general patterns of bacterial community assembly in fleas. An analysis of co-occurrence patterns suggests non-neutral negative interactions between dominant community members (Pspace (phylotype-based: R=0.418, Pspace and time.

Rapid and specific identification of Yersinia pestis by using a nested polymerase chain reaction procedure.

OpenAIRE

Campbell, J; Lowe, J; Walz, S; Ezzell, J

1993-01-01

We developed a 4-h nested polymerase chain reaction assay that detected a region of the plasminogen activator gene of Yersinia pestis in 100% of 43 Y. pestis strains isolated from humans, rats, and fleas yet was unreactive with the closely related species Yersinia enterocolitica and Yersinia pseudotuberculosis.

A comprehensive study on the role of the Yersinia pestis virulence markers in an animal model of pneumonic plague

NARCIS (Netherlands)

Kaman, W.E.; Hawkey, S.; van der Kleij, D.; Broekhuijsen, M.P.; Silman, N.J.; Bikker, F.J.

2011-01-01

Yersinia pestis, the Gram-negative bacterial agent of plague, is a zoonotic pathogen that primarily infects wild rodents and is transmitted by fleas. Y. pestis is one of the most invasive and virulent bacterial pathogens and has caused devastating pandemics, including the Black Death of 14th century

Ectoparasite diversity in the eastern rock sengis ( Elephantulus ...

African Journals Online (AJOL)

Ectoparasite diversity in the eastern rock sengis ( Elephantulus myurus ): the effect of seasonality and host sex. ... The ectoparasite assemblage comprised 11 groups of tick species, a single mite family, one louse and two flea species, with ticks and mites being the most numerous ectoparasites recovered. The prevalence ...

on in vitro callus initiation using leaf of artemisia annua

African Journals Online (AJOL)

insecticidal, anticancerous, antiseptic and febrifuge properties. It's oil has been found to repel fleas, mosquitoes and killed house flies(Morton 1981).In antiquity, plants of the genus Artemisia were also used to control the pangs of childbirth, regulate women's menstrual disorders, and as an abortifacient. In 1969, the Chinese.

Human activity spaces and plague risks in three contrasting ...

African Journals Online (AJOL)

Since 1980 plague has been a human threat in the Western Usambara Mountains in Tanzania. However, the spatial-temporal pattern of plague occurrence remains poorly understood. The main objective of this study was to gain understanding of human activity patterns in relation to spatial distribution of fleas in Lushoto ...

Applicator Training Manual for: Industrial, Institutional, Structural and Health-Related Pest Control.

Science.gov (United States)

Christensen, Christian M.; Scheibner, R. A.

This manual gives descriptions and diagrams for identification of the following types of pests: four species of cockroach; ants; bees and wasps; parasitic pests of man such as bedbugs, fleas, and ticks; occasional invaders such as flies and millipedes; silverfish and firebrats; beetles; termites; moths; fungi; and vertebrates including rodents,…

Swimming behaviour of Daphnia clones: differentiation through predator infochemicals

NARCIS (Netherlands)

Weber, A.; Van Noordwijk, A.J.

2002-01-01

We studied variation in small-scale swimming behavior (SSB) in four clones of Daphnia galeata (water flea) in response to predator infochemicals. The aim of this study was 3-fold. First, we tested for differences in SSB in Daphnia; second, we examined the potential of differences in SSB to explain

75 FR 22252 - Cyromazine; Pesticide Tolerances

Science.gov (United States)

2010-04-28

...-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets). Cyromazine is not registered for any specific use patterns that would result in... prenatal and postnatal toxicity and the completeness of the database on toxicity and exposure unless EPA...

The effect of pH on the uptake and toxicity of the bivalent weak base chloroquine tested on Salix viminalis and Daphnia magna

DEFF Research Database (Denmark)

Rendal, Cecilie; Kusk, Kresten Ole; Trapp, Stefan

2011-01-01

, and therefore a higher toxicity can be expected. The current study examines the pHdependent toxicity and bioaccumulation of the bivalent weak base chloroquine (pKa: 10.47 and 6.33, log KOW 4.67) tested on Salix viminalis (basket willow) and Daphnia magna (water flea). The transpiration rates of hydroponically...

75 FR 13125 - Pet Spot-On Analysis and Mitigation Plan Available for Public Comment; Notice of Availability

Science.gov (United States)

2010-03-18

... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0229; FRL-8816-8] Pet Spot-On Analysis and... registered pet spot-on products to control fleas and ticks and a mitigation plan. The analysis consists of a Technical Review Document and Data Evaluation Records for pet spot-on products. The Agency is requesting...

Direct evidence of Rickettsia typhi infection in Rhipicephalus ...

African Journals Online (AJOL)

These studies remarks that in addition to rats, other animals like cats, opossums and dogs could be implied in the transmission of Rickettsia typhi as infected fleas obtained from serologically positive animals have been detected in samples from endemic areas. In Mexico, the higher number of murine typhus cases have ...

Development Programs and the Maoist Insurgency in Andhra Pradesh and Chhattisgarh: A Comparative Analysis

Science.gov (United States)

2012-12-01

Praveen Swami, “India’s Counter-insurgency Conundrum,” Hindu, July 23, 2010, http://www.hindu.com/2010/07/23/stories/2010072354911200.htm. 27 Varun Vira... Praveen . “India’s Counter-Insurgency Conundrum.” Hindu, July 23, 2010. Taber, Robert. War of the Flea: The Classic Study of Guerilla Warfare. Dulles

21 CFR 520.531 - Cythioate tablets.

Science.gov (United States)

2010-04-01

... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... of body weight every third day or twice a week. (2) Indications for use. Dogs, for control of fleas. (3) Limitations. For oral use in dogs only. Do not use in greyhounds or in animals that are pregnant...

Resistances to an insect herbivore and a phytopathogen in Barbarea vulgaris

DEFF Research Database (Denmark)

Christensen, Stina

pubescence; one has glabrous leaves and is therefore called G-type while the other has pubescent leaves and is called the P-type. The G-type is resistant to most genotypes of the flea beetle Phyllotreta nemorum as well as some other Brassicales specialists, and this resistance is conferred by saponins. The P...

Fast and Simple Detection of Yersinia pestis Applicable to Field Investigation of Plague Foci

Science.gov (United States)

Simon, Stéphanie; Demeure, Christian; Lamourette, Patricia; Filali, Sofia; Plaisance, Marc; Créminon, Christophe; Volland, Hervé; Carniel, Elisabeth

2013-01-01

Yersinia pestis, the plague bacillus, has a rodent-flea-rodent life cycle but can also persist in the environment for various periods of time. There is now a convenient and effective test (F1-dipstick) for the rapid identification of Y. pestis from human patient or rodent samples, but this test cannot be applied to environmental or flea materials because the F1 capsule is mostly produced at 37°C. The plasminogen activator (PLA), a key virulence factor encoded by a Y. pestis-specific plasmid, is synthesized both at 20°C and 37°C, making it a good candidate antigen for environmental detection of Y. pestis by immunological methods. A recombinant PLA protein from Y. pestis synthesized by an Escherichia coli strain was used to produce monoclonal antibodies (mAbs). PLA-specific mAbs devoid of cross-reactions with other homologous proteins were further cloned. A pair of mAbs was selected based on its specificity, sensitivity, comprehensiveness, and ability to react with Y. pestis strains grown at different temperatures. These antibodies were used to develop a highly sensitive one-step PLA-enzyme immunoassay (PLA-EIA) and an immunostrip (PLA-dipstick), usable as a rapid test under field conditions. These two PLA-immunometric tests could be valuable, in addition to the F1-disptick, to confirm human plague diagnosis in non-endemic areas (WHO standard case definition). They have the supplementary advantage of allowing a rapid and easy detection of Y. pestis in environmental and flea samples, and would therefore be of great value for surveillance and epidemiological investigations of plague foci. Finally, they will be able to detect natural or genetically engineered F1-negative Y. pestis strains in human patients and environmental samples. PMID:23383008

Parasitology and urban livestock farming in Nigeria : prevalence of ova in faecal and soil samples and animal ectoparasites in Makurdi

Directory of Open Access Journals (Sweden)

E.A. Omudu

2007-05-01

Full Text Available Domestic environmental pollution resulting from urban livestock farming was investigated in Makurdi using parasitological techniques. The test tube flotation technique was used for the parasitological analysis of animal faecal matter and soil samples collected from residential premises. Ectoparasitic fauna of dogs, goats, sheep and cattle cohabiting with humans within the same residential compound were also collected and identified. The hand-picking and body brushing methods were employed to search for ticks, fleas, lice and mites. Of the 150 soil samples examined, 55 (36.7 % were positive for 1 or more eggs of helminth parasites. There was no significant difference in the distribution of eggs in the soil samples from the 3 areas sampled (c2=0.046, df=2, P>0.05. Ascaris species were the dominant parasite eggs found. Of the 180 faecal samples examined, 107 (59.4 % were positive for 1 or more eggs of helminth parasites. Chi-square analysis showed no significant difference in the level of infection of different animal faeces sampled (c2=5.74, df=4, P>0.05. Ascaris species were again the dominating helminth parasite eggs found. There was also no significant difference in the prevalence of helminth eggs in the animal faecal samples from the 3 areas sampled (c2=5.99, df=4, P>0.05. A total of 1908 ectoparasites was recovered (ticks: 32.80 %; lice: 22.43 %; fleas: 22.06% and mite: 22.69 %. There was no significant difference in infestation animals between sexes (c2=0.10, df=4, P>0.05. The predominant genus encountered for ticks were Amblyomma, while Linognathus (43.90%, Ctenocephalides (97.38% and Sarcoptes (58.89 % were most predominant for lice, fleas and mites respectively. The public health implications of the findings, especially as these relate to the increasing incidence and prevalence of zoonotic infections, are discussed.

An integrated pest management program as a pests control strategy ...

African Journals Online (AJOL)

Phukubje, Justice

and document analysis tools. The findings of the survey revealed a significant ..... equipment, materials and know- how, cockroach control can be a ... and birds. • They go through the four life cycle stages of egg, larva, pupa, and imago (adult). • Always do a thorough inspection of collection; fleas can hide under mats with fur.

54 1.Jerry George Mwakanyamale, 2Richard K.A Towett,3Fariji ...

African Journals Online (AJOL)

defecate as well as lay eggs to the environment 1. The female flea remains in the skin for up to five .... simple remedies. 2. Medical personnel in Korogwe should be empowered with knowledge and budget for controlling the disease. 3. More research is needed to establish the prevalence of the problem in Tanzania as a.

76 FR 74696 - Implementation of the Methamphetamine Production Prevention Act of 2008

Science.gov (United States)

2011-12-01

..., research, and industrial purposes and to deter the diversion of controlled substances to illegal purposes...-person sales to a customer, whether by a regulated seller (e.g., grocery store, general merchandise store, drug store) (21 U.S.C. 802(46), (49)) or a mobile retail vendor (e.g., kiosk, flea market), (21 U.S.C...

High exposure to Tunga penetrans (Linnaeus, 1758 correlates with intensity of infestation

Directory of Open Access Journals (Sweden)

Hermann Feldmeier

2006-02-01

Full Text Available Tungiasis is a parasitic skin disease widespread in resource-poor urban and rural communities in Brazil. Inhabitants of an urban slum in Northeast Brazil were examined for the presence of tungiasis lesions and followed-up twice a week for a period of three weeks. Each time the number, stages, and topographic localization of lesions were recorded on a documentation sheet. The infestation rate (number of newly embedded sand fleas per individual and day remained stable during the observation period. The infestation rate was significantly related to the intensity of infestation (total number of lesions present (rho = 0.70, p < 0.0001 and the proportion of viable lesions (rho = 0.28, p < 0.0001. The results indicate that in an endemic area the infestation intensity and the proportion of viable lesions can be used as a proxy to assess the exposure of individuals at risk for tungiasis. Persistently high infestation rates during the transmission season favour the use of prevention measures against invading sand fleas (such as a repellent rather than a drug to kill already embedded parasites.

[ON THE ORIGIN OF HYPERVIRULENCE OF THE CAUSATIVE AGENT OF PLAGUE].

Science.gov (United States)

Anisimov, N V; Kislichkina, A A; Platonov, M E; Evseeva, V V; Kadnikova, L A; Lipatnikova, N A; Bogun, A G; Dentovskaya, S V; Anisimov, A P

2016-01-01

The attempt to combine Yersinia pseudotuberculosis and Yersinia pestis into one species has been unsupported by microbiologists due to the specific features of the epidemiology and clinical presentations of their induced diseases and to basic differences in their virulence. Pseudotuberculosis is predominantly a relatively mild human intestinal infection transmitted through contaminated food and plague is an acute generalized disease with high mortality, which is most frequently transmitted by the bites of infected fleas. Y. pestis hypervirulence, the ability of single bacteria to ensure the development of predagonal bacteriemia in rodents, which is sufficient to contaminate the fleas, is one of the main events during pathogen adaptation to a new ecological niche. By analyzing the data of molecular typing of the representative kits of naturally occurring Y. pestis isolates, the authois consider the issues of formation of intraspecies groups with universal hypervirulence, as well as biovars that are highly virulent only to their major host. A strategy for searching for selective virulence factors, the potential molecular targets for vaccination and etiotropic treatment of plague, is discussed.

[ON SOME DEBATABLE PROBLEMS OF THE NATURAL NIDALITY OF PLAGUE].

Science.gov (United States)

Verzhutsky, D B; Balakhonov, S V

2016-01-01

The communication substantiates the opinion that the theory of natural nidality of plague; which is based on the fundamental recognition that fleas play a leading role in the transmission and accumulation of the plague pathogen, cannot be disproved or substantially changed on the alternative weakly reasoned assumptions and hypotheses. All its "bottlenecks" are quite understandable when considering the long-term volumetric materials that have been gathered directly in nature and generalized in multiple publications. Plague is an obligate transmissive infection; its, agent is a highly specialized parasite that is completely associated in its vital activity with the only group of the blood-sucking insects--fleas and that is transmitted through periodic colonization of warm-blooded animals for a short time. All other types of plague microbe persistence in nature are either occasional or minor and do not play any significant role in pathogen persistence in the natural foci of this disease. There are no strong grounds for seriously considering the attempts to revise the main points of the theory of natural nidality of plague, which are widely held in current academic publications.

Fipronil and its degradates in indoor and outdoor dust

Science.gov (United States)

Mahler, B.J.; Van Metre, P.C.; Wilson, J.T.; Musgrove, M.; Zaugg, S.D.; Burkhardt, M.R.

2009-01-01

Fipronil is a potent insecticide used for control of termites, fleas, roaches, ants, and other pests. We measured fipronil, fipronil sulfide, and desulfinyl fipronil concentrations in indoor and outdoor dust from 24 residences in Austin, Texas. At least one of these three fipronil compounds was detected in every sample. Fipronil accounted for most of the total fipronil (T-fipronil; fipronil+desulfinyl fipronil+fipronil sulfide), followed by desulfinyl fipronil and fipronil sulfide. Nineteen of 24 samples of indoor dust had T-fipronil concentrations less than 270 ??g/kg; the remaining five had concentrations from 1320 to 14,200 ??g/kg. All three of the residences with a dog on which a flea-control product containing fipronil was used were among the five residences with elevated fipronil concentrations. In outdoor dust, all concentrations of T-fipronil were less than 70??g/kg with one exception (430??g/kg). For every residence, the concentration of T-fipronil in indoor dust exceeded that in outdoor dust, and the median concentration of T-fipronil was 15 times higher indoors than outdoors.

Use it or lose it: reproductive implications of ecological specialization in a haematophagous ectoparasite.

Science.gov (United States)

Arbiv, A; Khokhlova, I S; Ovadia, O; Novoplansky, A; Krasnov, B R

2012-06-01

Using experimentally induced disruptive selection, we tested two hypotheses regarding the evolution of specialization in parasites. The 'trade-off' hypothesis suggests that adaptation to a specific host may come at the expense of a reduced performance when exploiting another host. The alternative 'relaxed selection' hypothesis suggests that the ability to exploit a given host would deteriorate when becoming obsolete. Three replicate populations of a flea Xenopsylla ramesis were maintained on each of two rodent hosts, Meriones crassus and Dipodillus dasyurus, for nine generations. Fleas maintained on a specific host species for a few generations substantially decreased their reproductive performance when transferred to an alternative host species, whereas they generally did not increase their performance on their maintenance host. The results support the 'relaxed selection' hypothesis of the evolution of ecological specialization in haematophagous ectoparasites, while suggesting that trade-offs are unlikely drivers of specialization. Further work is needed to study the extent by which the observed specializations are based on epigenetic or genetic modifications. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Bacillary angiomatosis: A rare finding in the setting of antiretroviral ...

African Journals Online (AJOL)

eases in humans.[1] The two most commonly associated with HIV are B. quintana and. B. henselae.[1,2,5] Transmission of Bartonella to humans occurs via a cat scratch that is contaminated with Bartonella-infected fleas.[1,2,5,6] The prevalence of Bartonella in. HIV-positive persons is reported to be very. CASE REPORT.

Rickettsia asembonensis Characterization by Multilocus Sequence Typing of Complete Genes, Peru.

Science.gov (United States)

Loyola, Steev; Flores-Mendoza, Carmen; Torre, Armando; Kocher, Claudine; Melendrez, Melanie; Luce-Fedrow, Alison; Maina, Alice N; Richards, Allen L; Leguia, Mariana

2018-05-01

While studying rickettsial infections in Peru, we detected Rickettsia asembonensis in fleas from domestic animals. We characterized 5 complete genomic regions (17kDa, gltA, ompA, ompB, and sca4) and conducted multilocus sequence typing and phylogenetic analyses. The molecular isolate from Peru is distinct from the original R. asembonensis strain from Kenya.

First record of a Neozygites species (Zygomycetes:Entomophthorales) infecting springtails (Insecta:Collembola)

DEFF Research Database (Denmark)

Steenberg, T.; Eilenberg, J.; Bresciani, J.

1996-01-01

A fungal pathogen from the Entomophthorales (Zygomycetes) was discovered in populations of the lucerne flea Sminthurus viridis (Collembola) collected from grassland and leguminous crops in Denmark during July to October. The morphology of the fungus was studied in springtails, collected live, whi...... Conidiobolus coronatus. Verticillium lecanii and Beauveria bassiana (Deuteromycotina:Hyphomycetes) were also isolated from S. viridis....

Does myxomatosis still regulate numbers of rabbits (Oryctolagus cuniculus Linnaeus, 1758) in the United Kingdom?

Science.gov (United States)

Trout, R C; Ross, J; Fox, A P

1993-03-01

Myxomatosis now kills a much smaller proportion of rabbit populations than in the past, while remaining an important regulatory factor, as shown experimentally. On two separate occasions, experimental reduction of the prevalence of the disease (by reducing infestations of the main vector, the rabbit flea) led to significant increases in numbers of rabbits surviving the winter.

University of Louisville Holds Fast to Plans for Big-Time Sports

Science.gov (United States)

Sander, Libby

2009-01-01

For five decades, the University of Louisville men's basketball team has played its home games at the state's fairgrounds, in a modest arena originally built for horse shows. And for just as many seasons, the team's toughest competition for scheduling has come from the livestock--and the flea markets and tractor pulls that also vie for the space.…

Primera cita de Sternopsylla distincta speciosa (Siphonaptera: Ischnopsyllidae para la provincia de Jujuy, Argentina

Directory of Open Access Journals (Sweden)

Analía G. AUTINO

2005-01-01

Full Text Available Se cita por primera vez para Jujuy la presencia de pulgas ectoparásitas de murciélagos, habiéndose registrado a Sternopsylla distincta speciosa Johnson sobre Tadarida brasiliensis (Geoffroy (Chiroptera: Vespertilionidae. Además se presentan comentarios sobre caracteres de morfología externa y estructuras genitales de las subespecies Sternopsylla distincta speciosa Johnson y Sternopsylla distincta distincta (Rothschild.

Possible living flea beetle fossil in Bolivia: A new genus of flea beetles with modified hind legs (Coleoptera: Chrysomelidae: Galerucinae: Alticini)

Science.gov (United States)

A new genus (Chanealtica) with three new species (C. cuevas, C. ellimon, and C. maxi) from Bolivia is described and illustrated. It is compared with Aphthonoides Jacoby 1885, Argopistes Motschulsky 1860, Metroserrapha Bechyne 1958, Psylliodes Berthold 1827 and Psyllototus Nadein 2010. Remarkably, ba...

[The plague in Finland in 1710].

Science.gov (United States)

Engström, N G

1994-01-01

In the autumn of 1710 Helsinki was struck by the so-called oriental plague during four months. The infection was transferred by black rats which harboured fleas. The flea-bites caused boils. It was believed that the plague was air-borne, and the air was very humid that autumn. Big fires were lit in order to reduce the humidity, the purpose being to make it easier for the infected to breathe. Attempts were also made to dissect the boils. The carriers of the contamination came as refugees from Estland over the Gulf of Finland. The infection had spread from Turkey to Poland and Balticum after the defeat of the Finnish-Swedish army in the summer of 1709 at Poltava in Ucraine. Helsingfors (Helsinki) was struck extremely hard. About two-thirds of the inhabitants died of the pestilence. Some escaped by fleeing to the countryside. The plague spread through the country as far north as to Uleåborg (Oulu) and Cajana (Kajaani). Marketplaces became important centres of infection. With the advent of the frost in December the plague dwindled. At that time Helsinki was practically a dead town.

Sarcoptic mange and other ectoparasitic infections in a red fox (Vulpes vulpes population from central Italy

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S. Perrucci

2016-06-01

Full Text Available Fifty red foxes (Vulpes vulpes from the district of Pisa (central Italy were examined for ectoparasites. Sarcoptic mange was diagnosed on the presence of clearly visible skin lesions with confirmatory demonstration of Sarcoptes scabiei at parasitological and histopathological analysis. Ticks and fleas were collected directly from the carcases during post mortem examination, fixed and identified by morphological examination. For the detection of ear Malassezia and mite infections, cytological and parasitological examinations of ear wax samples were performed. All data were statistically analysed using a χ2 test with the Yates correction. An overall prevalence of 84% for ectoparasitic infections was found in examined subjects. In regard to isolated ectoparasites, 38%, 8%, 82%, 6% and 8% of foxes resulted positive for S. scabiei, Otodectes cynotis, Malassezia spp., fleas (Archaeopsylla erinacei, Pulex irritans, Ctenocephalides canis and ticks (Ixodes ricinus and Rhipicephalus sanguineus, respectively. Malassezia ear infection was significantly more prevalent in animals older than 1 year (P < 0.01. Prevalence (38%, severity of lesions and poor body conditions observed in most Sarcoptes-infected animals indicate that sarcoptic mange should be considered the most important ectoparasitic infection of red foxes in the examined area.

Regulation of Biofilm Formation by Hfq is Influenced by Presence of Plasmid pCD1 in Yersinia Pestis Biovar Microtus

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Huiying Yang

2017-10-01

Full Text Available Yersinia pestis synthesizes the attached biofilms in the flea gut to promotethe flea-borne transmission of this deadly pathogen. Bellows et al. reported that the posttranscriptional regulator Hfq inhibites biofilm formation in apCD1− derivative of Y. pestis CO92, however, we found that Hfq stimulates biofilm production in a microtus strain of Y. pestis with the typical plasmids, including pCD1. When we cured pCD1 from this strain, the biofilm phenotype was in accordance with that reported by Bellows et al., indicating that the unknown pCD1-associated factors modulating the regulatory pathways of Y. pestis biofilm formation. Further gene regulation experiments using relevant pCD1+ Y. pestis strains disclose that Hfq positively regulates the expression of hmsHFRS and hmsT encoding a diguanylate cyclase while negatively regulates the expression of hmsP encoding the sole phosphodiesterase. However, Hfq has no regulatory effect on the expression of hmsCDE at the mRNA and protein levels. Our results suggest that we should be cautious to make conclusion from results based on the pCD1-cured Y. pestis.

Murine Typhus: An Important Consideration for the Nonspecific Febrile Illness

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Gurjot Basra

2012-01-01

Full Text Available Murine typhus is a widely distributed flea-borne infection caused by Rickettsia typhi. Symptoms of murine typhus are nonspecific and mimic a variety of other infectious diseases. We herein report a case of murine typhus in an area where the broad use of DDT in the mid-20th century has now made it a rare disease. The patient described presented with headache, fever, and a faint macular rash. Initial laboratory studies revealed a slight transaminase elevation. Further questioning revealed exposure to opossums, prompting the consideration of murine typhus as a diagnosis. Although typhus group antibodies were not present during the patient’s acute illness, empiric therapy with doxycycline was initiated, and the patient defervesced. One month after convalescence, the patient returned to clinic with serum that contained typhus group antibodies with an IgG titer of 1 : 1024. Murine typhus is an important consideration during the workup of a patient with a nonspecific febrile illness. Exposure to reservoir hosts and the flea vector place humans at risk for this disease. Clinician recognition of this entity is required for diagnosis and effective therapy.

Rickettsial Disease in the Peruvian Amazon Basin.

Science.gov (United States)

Kocher, Claudine; Morrison, Amy C; Leguia, Mariana; Loyola, Steev; Castillo, Roger M; Galvez, Hugo A; Astete, Helvio; Flores-Mendoza, Carmen; Ampuero, Julia S; Bausch, Daniel G; Halsey, Eric S; Cespedes, Manuel; Zevallos, Karine; Jiang, Ju; Richards, Allen L

2016-07-01

Using a large, passive, clinic-based surveillance program in Iquitos, Peru, we characterized the prevalence of rickettsial infections among undifferentiated febrile cases and obtained evidence of pathogen transmission in potential domestic reservoir contacts and their ectoparasites. Blood specimens from humans and animals were assayed for spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) by ELISA and/or PCR; ectoparasites were screened by PCR. Logistic regression was used to determine associations between patient history, demographic characteristics of participants and symptoms, clinical findings and outcome of rickettsial infection. Of the 2,054 enrolled participants, almost 2% showed evidence of seroconversion or a 4-fold rise in antibody titers specific for rickettsiae between acute and convalescent blood samples. Of 190 fleas (Ctenocephalides felis) and 60 ticks (Rhipicephalus sanguineus) tested, 185 (97.4%) and 3 (5%), respectively, were positive for Rickettsia spp. Candidatus Rickettsia asemboensis was identified in 100% and 33% of the fleas and ticks tested, respectively. Collectively, our serologic data indicates that human pathogenic SFGR are present in the Peruvian Amazon and pose a significant risk of infection to individuals exposed to wild, domestic and peri-domestic animals and their ectoparasites.

Research in Biological and Medical Sciences, Including Biochemistry, Communicable Disease and Immunology Internal Medicine, Nuclear Medicine, Physiology, Psychiatry, Surgery, and Veterinary Medicine

Science.gov (United States)

1976-07-01

the virus overwintered in hibernating Culex plpiens. Mosquitoes were collected from underground bunkers at a number of abandoned Army forts located...determinants and antibiotic sensitivities. Straius examined (43) from South Vietnam, Java , and the USA produced Fraction 1 antigen, VW antigens...Organization (WHO) staff in Java from various rodents and fleas were also studied. The nine strains of Y. pestis obtained during 1974 from Vietnamese

Medical Technology Base Master Plan

Science.gov (United States)

1990-03-01

trflpical areas relatcd Equin Encephalitis (’(FE) was developed, to 70 plague epidemics to weatlier as a functmo of flea physi. A malarnma...havo increased the likelihood of bum injuries. Bum treatment requires 8 huge investment of professional resources In terms of physicians, nurses , and...Support ai General Hospitais and Convalescent Centers 46 Inadequate Veterinary Support of Military Worlking Dogs ,MWD) Figurti VI-2. AMEOID Capab~ility

Human Infection with Rickettsia felis, Kenya

Science.gov (United States)

2010-07-01

Human Infection with Rickettsia felis, Kenya Allen L. Richards, Ju Jiang, Sylvia Omulo, Ryan Dare, Khalif Abdirah~a~, P:bdile Ali, Shanaaz K...infection with obligate intracellular rickettsiae , which are transmitted to humans by arthropod vectors (e.g., lice, fleas, ticks, and mites... Rickettsiae are associated with arthropods for a least a part of their life cycle and are passed to other arthropods by transovarial transmission or

Incidence and Management Costs of Freshwater Aquatic Nuisance Species at Projects Operated by the U.S. Army Corps of Engineers

Science.gov (United States)

2010-07-01

the occurrence of ANS impacts (Yes or No) from freshwater algae, large aquatic plants, fish, zebra mussels, Asiatic clams, water fleas, crayfish...2005. Freshwater aquatic nuisance species impacts and management costs and benefits at federal water resources projects. ERDC/TN ANSRP-06-3...ER D C/ EL T R- 10 -1 3 Aquatic Nuisance Species Research Program Incidence and Management Costs of Freshwater Aquatic Nuisance Species

Hazard identification and risk characterization of bisphenols A, F and AF to aquatic organisms.

Science.gov (United States)

Tišler, Tatjana; Krel, Alja; Gerželj, Urška; Erjavec, Boštjan; Dolenc, Marija Sollner; Pintar, Albin

2016-05-01

Production of bisphenol A (BPA) analogues such as bisphenol F (BPF) and bisphenol AF (BPAF) has recently increased, due to clear evidence of adverse effects of BPA on humans and wildlife. Bisphenols (BPs) have already been released into aquatic environment without previous available information about potential adverse effects of BPs and their potential risk to aquatic ecosystems. In this study, lethal and sublethal effects of BPF and BPAF to bacteria, algae, crustacea and fish embryos were investigated and the results were compared to the adverse effects obtained for BPA. We found that BPAF was the most toxic compound to Daphnia magna, Danio rerio and Desmodesmus subspicatus; the lowest 72 h EC50 (median effective concentration) and 21 d NOEC (no observed effect concentration) values were determined at 2.2 mg/L regarding zebrafish hatching success and 0.23 mg/L of BPAF obtained for growth and reproduction of water fleas, respectively. In most cases, BPA was more toxic to D. magna, D. rerio and D. subspicatus in comparison to BPF, but pigmentation of zebrafish embryos after 48 h of exposure and reproduction of water fleas after 21-day D. magna reproductive test exposure to BPF were much more impaired. Risk quotients (measured environmental concentration/21 d NOEC) showed that BPA, BPF and BPAF are recently not chronically hazardous to the survival, reproduction and growth of water fleas in surface waters. On the other hand, we importantly show that currently present BPAF concentrations in surface waters could cause a potential ecological risk to aquatic organisms. In the near future, higher concentrations of BPF and BPAF in surface waters are anticipated and for this reason further testing using test systems with various aquatic species and endpoints are needed to provide additional information about toxic impacts of BPF and BPAF on aquatic biota. Copyright © 2016 Elsevier Ltd. All rights reserved.

An Experimental Insight into Extracellular Phosphatases – Differential Induction of Cell-Specific Activity in Green Algae Cultured under Various Phosphorus Conditions

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Jaroslav Vrba

2018-02-01

Full Text Available Extracellular phosphatase activity (PA has been used as an overall indicator of P depletion in lake phytoplankton. However, detailed insights into the mechanisms of PA regulation are still limited, especially in the case of acid phosphatases. The novel substrate ELF97 phosphate allows for tagging PA on single cells in an epifluorescence microscope. This fluorescence-labeled enzyme activity (FLEA assay enables for autecological studies in natural phytoplankton and algal cultures. We combined the FLEA assay with image analysis to measure cell-specific acid PA in two closely related species of the genus Coccomyxa (Trebouxiophyceae, Chlorophyta isolated from two acidic lakes with distinct P availability. The strains were cultured in a mineral medium supplied with organic (beta-glycerol phosphate or inorganic (orthophosphate P at three concentrations. Both strains responded to experimental conditions in a similar way, suggesting that acid extracellular phosphatases were regulated irrespectively of the origin and history of the strains. We found an increase in cell-specific PA at low P concentration and the cultures grown with organic P produced significantly higher (ca. 10-fold PA than those cultured with the same concentrations of inorganic P. The cell-specific PA measured in the cultures grown with the lowest organic P concentration roughly corresponded to those of the original Coccomyxa population from an acidic lake with impaired P availability. The ability of Coccomyxa strains to produce extracellular phosphatases, together with tolerance for both low pH and metals can be one of the factors enabling the dominance of the genus in extreme conditions of acidic lakes. The analysis of frequency distribution of the single-cell PA documented that simple visual counting of ‘active’ (labeled and ‘non-active’ (non-labeled cells can lead to biased conclusions regarding algal P status because the actual PA of the ‘active’ cells can vary from

Distribución y Hospederos de pulgas (Siphonaptera en la Provincia de Ayabaca, Piura - 1999

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Edwar J Pozo

2005-10-01

Full Text Available Estudio descriptivo transversal realizado en la provincia de Ayabaca (zona endémica de peste bubónica, departamento de Piura, Perú; con el objetivo de ampliar los conocimientos sobre las especies de pulgas presentes. Fueron colectados 10 152 especimenes de pulgas en 46 localidades pertenecientes a seis distritos de la provincia de Ayabaca (Suyo, Sapillica, Montero, Paimas, Lagunas y Ayabaca, entre los meses de enero a julio de 1999. El muestreo se realizó seleccionando para cada vivienda un mínimo de cinco ropas de cama y cinco cuyes (Cavia porcellus además de la totalidad de los roedores capturados en las viviendas y en el área silvestre. Ocho especies de pulgas fueron identificadas (Pulex irritans, Tiamastus cavicola, Polygenis litargus, Xenopsylla cheopis, Ctenocephalides felis, Craneopsylla minerva, Leptopsylla segnis y Cediopsylla spillmanni de éstas, P. irritans se reportó en todos los distritos muestreados, seguida de X. cheopis y P. litargus, encontradas en cinco de los seis distritos.

Infective endocarditis associated with Bartonella henselae: A case series

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Akio Nakasu

Full Text Available Organisms in the genus Bartonella are cause of blood culture-negative endocarditis. Bartonella infective endocarditis is being increasingly reported worldwide; however, reports from Japan are limited. Here, we report five cases of infective endocarditis associated with Bartonella henselae. All patients had a history of contact with cats or fleas; this information helped achieve an appropriate diagnosis. Keywords: Infective endocarditis, Blood culture-negative endocarditis, Bartonella henselae, Infection, Bartonella, Endocarditis

Et tilfaelde af tungiasis efter rejse i Kenya

DEFF Research Database (Denmark)

Rathe, Mathias; Rafn, Aase Cederlund; Poulsen, Thorkil

2009-01-01

Tungiasis is an ectoparasitic skin disease caused by infestation by the female sand flea, Tunga penetrans. Prevalence in endemic areas may reach 83%, while it is rare in non-endemic areas. However, an increase in international travel to and from the affected regions may lead to a rise in the numb...... of cases in non-endemic countries. We present a Danish case of tungiasis contracted during a trip to Kenya....

Outbreaks of Rickettsia felis in Kenya and Senegal, 2010

Centers for Disease Control (CDC) Podcasts

2010-06-09

This podcast describes the outbreak of Rickettsia felis in Kenya between August 2006 and June 2008, and in rural Senegal from November 2008 through July 2009. CDC infectious disease pathologist Dr. Chris Paddock discusses what researchers learned about this flea-borne disease and how to prevent infection.  Created: 6/9/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/24/2010.

Predicting small mammal and flea abundance using landform and ...

African Journals Online (AJOL)

Small mammals particularly rodents, are considered the primary natural hosts of plague. Literature suggests that plague persistence in natural foci has a root cause in soils. The objective of this study was to investigate the relationship between on the one hand landforms and associated soil properties, and on the other hand ...

Water fleas require microbiota for survival, growth and reproduction.

Science.gov (United States)

Sison-Mangus, Marilou P; Mushegian, Alexandra A; Ebert, Dieter

2015-01-01

Microbiota have diverse roles in the functioning of their hosts; experiments using model organisms have enabled investigations into these functions. In the model crustacean Daphnia, little knowledge exists about the effect of microbiota on host well being. We assessed the effect of microbiota on Daphnia magna by experimentally depriving animals of their microbiota and comparing their growth, survival and fecundity to that of their bacteria-bearing counterparts. We tested Daphnia coming from both lab-reared parthenogenetic eggs of a single genotype and from genetically diverse field-collected resting eggs. We showed that bacteria-free hosts are smaller, less fecund and have higher mortality than those with microbiota. We also manipulated the association by exposing bacteria-free Daphnia to a single bacterial strain of Aeromonas sp., and to laboratory environmental bacteria. These experiments further demonstrated that the Daphnia-microbiota system is amenable to manipulation under various experimental conditions. The results of this study have implications for studies of D. magna in ecotoxicology, ecology and environmental genomics.

Factors influencing Dipylidium sp. infection in a free-ranging social carnivore, the spotted hyaena (Crocuta crocuta).

Science.gov (United States)

East, Marion L; Kurze, Christoph; Wilhelm, Kerstin; Benhaiem, Sarah; Hofer, Heribert

2013-12-01

We provide the first genetic sequence data for a Dipylidium species from a wild carnivore plus an analysis of the effects of ecological, demographic, physiological and behavioural factors on Dipylidium sp. infection prevalence in a social carnivore, the spotted hyaena (Crocuta crocuta), in the Serengeti National Park, Tanzania. Our sequence data from a mitochondrial gene fragment (1176 base pair long) had a similarity of between 99% and 89% to Dipylidium caninum. We determined infection prevalence in 146 faecal samples from 124 known animals in three social groups (termed clans) using molecular screening and Dipylidium proglottid presence. Our analysis revealed significantly higher infection prevalence in juveniles (55%) than adults (15.8%), indicating that predominantly juveniles maintained infection in clans. The likelihood of infection in juveniles significantly: (1) increased as the number of adults and older juveniles (>6 months) at communal dens increased, implying a positive relationship between this factor and the size of the intermediate host (probably a flea species) population at communal dens; (2) decreased as the number of younger juveniles (Dipylidium fecundity and hence decrease infection prevalence in the den flea population. Our study provides useful insights into Dipylidium epidemiology in a social carnivore population subject to large fluctuations in prey abundance.

Factors influencing Dipylidium sp. infection in a free-ranging social carnivore, the spotted hyaena (Crocuta crocuta)☆

Science.gov (United States)

East, Marion L.; Kurze, Christoph; Wilhelm, Kerstin; Benhaiem, Sarah; Hofer, Heribert

2013-01-01

We provide the first genetic sequence data for a Dipylidium species from a wild carnivore plus an analysis of the effects of ecological, demographic, physiological and behavioural factors on Dipylidium sp. infection prevalence in a social carnivore, the spotted hyaena (Crocuta crocuta), in the Serengeti National Park, Tanzania. Our sequence data from a mitochondrial gene fragment (1176 base pair long) had a similarity of between 99% and 89% to Dipylidium caninum. We determined infection prevalence in 146 faecal samples from 124 known animals in three social groups (termed clans) using molecular screening and Dipylidium proglottid presence. Our analysis revealed significantly higher infection prevalence in juveniles (55%) than adults (15.8%), indicating that predominantly juveniles maintained infection in clans. The likelihood of infection in juveniles significantly: (1) increased as the number of adults and older juveniles (>6 months) at communal dens increased, implying a positive relationship between this factor and the size of the intermediate host (probably a flea species) population at communal dens; (2) decreased as the number of younger juveniles (Dipylidium fecundity and hence decrease infection prevalence in the den flea population. Our study provides useful insights into Dipylidium epidemiology in a social carnivore population subject to large fluctuations in prey abundance. PMID:24533344

The Effect of Seasonal Weather Variation on the Dynamics of the Plague Disease

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Rigobert C. Ngeleja

2017-01-01

Full Text Available Plague is a historic disease which is also known to be the most devastating disease that ever occurred in human history, caused by gram-negative bacteria known as Yersinia pestis. The disease is mostly affected by variations of weather conditions as it disturbs the normal behavior of main plague disease transmission agents, namely, human beings, rodents, fleas, and pathogens, in the environment. This in turn changes the way they interact with each other and ultimately leads to a periodic transmission of plague disease. In this paper, we formulate a periodic epidemic model system by incorporating seasonal transmission rate in order to study the effect of seasonal weather variation on the dynamics of plague disease. We compute the basic reproduction number of a proposed model. We then use numerical simulation to illustrate the effect of different weather dependent parameters on the basic reproduction number. We are able to deduce that infection rate, progression rates from primary forms of plague disease to more severe forms of plague disease, and the infectious flea abundance affect, to a large extent, the number of bubonic, septicemic, and pneumonic plague infective agents. We recommend that it is more reasonable to consider these factors that have been shown to have a significant effect on RT for effective control strategies.

Re-emergence of tularemia in Germany: Presence of Francisella tularensis in different rodent species in endemic areas

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Pfeffer Martin

2008-11-01

Full Text Available Abstract Background Tularemia re-emerged in Germany starting in 2004 (with 39 human cases from 2004 to 2007 after over 40 years of only sporadic human infections. The reasons for this rise in case numbers are unknown as is the possible reservoir of the etiologic agent Francisella (F. tularensis. No systematic study on the reservoir situation of F. tularensis has been published for Germany so far. Methods We investigated three areas six to ten months after the initial tularemia outbreaks for the presence of F. tularensis among small mammals, ticks/fleas and water. The investigations consisted of animal live-trapping, serologic testing, screening by real-time-PCR and cultivation. Results A total of 386 small mammals were trapped. F. tularensis was detected in five different rodent species with carrier rates of 2.04, 6.94 and 10.87% per trapping area. None of the ticks or fleas (n = 432 tested positive for F. tularensis. We were able to demonstrate F. tularensis-specific DNA in one of 28 water samples taken in one of the outbreak areas. Conclusion The findings of our study stress the need for long-term surveillance of natural foci in order to get a better understanding of the reasons for the temporal and spatial patterns of tularemia in Germany.

Emerging arthropod-borne diseases of companion animals in Europe.

Science.gov (United States)

Beugnet, Frederic; Marié, Jean-Lou

2009-08-26

Vector-borne diseases are caused by parasites, bacteria or viruses transmitted by the bite of hematophagous arthropods (mainly ticks and mosquitoes). The past few years have seen the emergence of new diseases, or re-emergence of existing ones, usually with changes in their epidemiology (i.e. geographical distribution, prevalence, and pathogenicity). The frequency of some vector-borne diseases of pets is increasing in Europe, i.e. canine babesiosis, granulocytic anaplasmosis, canine monocytic ehrlichiosis, thrombocytic anaplasmosis, and leishmaniosis. Except for the last, these diseases are transmitted by ticks. Both the distribution and abundance of the three main tick species, Rhipicephalus sanguineus, Dermacentor reticulatus and Ixodes ricinus are changing. The conditions for such changes involve primarily human factors, such as travel with pets, changes in human habitats, social and leisure activities, but climate changes also have a direct impact on arthropod vectors (abundance, geographical distribution, and vectorial capacity). Besides the most known diseases, attention should be kept on tick-borne encephalitis, which seems to be increasing in western Europe, as well as flea-borne diseases like the flea-transmitted rickettsiosis. Here, after consideration of the main reasons for changes in tick vector ecology, an overview of each "emerging" vector-borne diseases of pets is presented.

Chesapeake Bay Study. Supplement A. Problem Identification. Supplement B. Public Involvement. Supplement C. The Chesapeake Bay Hydraulic Model.

Science.gov (United States)

1984-09-01

Amphipod (5 genera) Canvasback Sand flea Lesser scaup Cnidaria 4’ Grass shrimp 4’ Bufflehead 4 Sand shrimp ** Osprey " Stinging nettle 4’ Xanthid crab (2...thereby decreasing the amounts of available oxygen in the water and, in extreme cases, causing fish kills. In addition, the use of insecticides in...where demands are the greatest. The stinging sea nettle and the closely related comb A-79 f. . . . . . • _ . . ... . .. jellies or ctenophores which

Et tilfaelde af tungiasis efter rejse i Kenya

DEFF Research Database (Denmark)

Rathe, Mathias; Rafn, Aase; Poulsen, Thorkil

2009-01-01

Tungiasis is an ectoparasitic skin disease caused by infestation by the female sand flea, Tunga penetrans. Prevalence in endemic areas may reach 83%, while it is rare in non-endemic areas. However, an increase in international travel to and from the affected regions may lead to a rise in the numb...... of cases in non-endemic countries. We present a Danish case of tungiasis contracted during a trip to Kenya. Udgivelsesdato: 2009-Mar-2...

THE DISTRIBUTION OF RICKETTSIA IN THE TISSUES OF INSECTS AND ARACHNIDS.

Science.gov (United States)

Cowdry, E V

1923-03-31

In the absence of a satisfactory definition of Rickettsia the observations herein recorded were arbitrarily limited to bacterium-like organisms which are intracellular and Gram-negative. Rickettsia of this type were found in the following species: Amblyomma americana, Amblyomma hebraeum, Boophilus decoloratus, Atomus sp., Casinaria infesta, Chrysopa oculata, Ctenocephalus canis, Dermacentor variabilis, Lepisma saccharina, Lucoppia curviseta, Margaropus annulatus, Margaropus annulatus australis, Ornithodoros turicata, Pulex irritans, Rhipicephalus sanguineus, Rhipicephalus evertsi, and Salticus scenicus. Since intracellular, Gram-negative Rickettsia have been recorded in the literature as existing in Cimex lectularius, Dermacentor venustus, Melophagus ovinus, and Pediculus humanus, the occasional occurrence of such bodies must be conceded in the following groups not closely related phylogenetically: Attidae, Trombidiidae, Argasidae, lxodidae, Cinura, Acanthiidae, Pediculidae, Hippoboscidae, Chrysopidae, Pulicidae, and Ichneumonidae. The species which harbor Rickettsia differ widely in diet and habitat. One such species is insectivorous throughout life, two are insectivorous in larval stages, becoming vegetarian in the adult condition, one is chiefly vegetarian but partakes of some animal products, and two are usually entirely vegetarian; while the remainder subsist wholly upon a diet of mammalian blood. Rickettsia are associated, in only a few cases, with diseases in mammals. The evidence at hand does not lead beyond the conclusion that the Rickettsia mentioned above are true Gram-negative microorganisms, easily distinguishable from mitochondria and all other cytoplasmic and nuclear granulations, rather completely adapted to an intracellular existence, exhibiting in some cases a remarkable degree of host specificity, and often inherited through the eggs.

Delineation and analysis of chromosomal regions specifying Yersinia pestis.

Science.gov (United States)

Derbise, Anne; Chenal-Francisque, Viviane; Huon, Christèle; Fayolle, Corinne; Demeure, Christian E; Chane-Woon-Ming, Béatrice; Médigue, Claudine; Hinnebusch, B Joseph; Carniel, Elisabeth

2010-09-01

Yersinia pestis, the causative agent of plague, has recently diverged from the less virulent enteropathogen Yersinia pseudotuberculosis. Its emergence has been characterized by massive genetic loss and inactivation and limited gene acquisition. The acquired genes include two plasmids, a filamentous phage, and a few chromosomal loci. The aim of this study was to characterize the chromosomal regions acquired by Y. pestis. Following in silico comparative analysis and PCR screening of 98 strains of Y. pseudotuberculosis and Y. pestis, we found that eight chromosomal loci (six regions [R1pe to R6pe] and two coding sequences [CDS1pe and CDS2pe]) specified Y. pestis. Signatures of integration by site specific or homologous recombination were identified for most of them. These acquisitions and the loss of ancestral DNA sequences were concentrated in a chromosomal region opposite to the origin of replication. The specific regions were acquired very early during Y. pestis evolution and were retained during its microevolution, suggesting that they might bring some selective advantages. Only one region (R3pe), predicted to carry a lambdoid prophage, is most likely no longer functional because of mutations. With the exception of R1pe and R2pe, which have the potential to encode a restriction/modification and a sugar transport system, respectively, no functions could be predicted for the other Y. pestis-specific loci. To determine the role of the eight chromosomal loci in the physiology and pathogenicity of the plague bacillus, each of them was individually deleted from the bacterial chromosome. None of the deletants exhibited defects during growth in vitro. Using the Xenopsylla cheopis flea model, all deletants retained the capacity to produce a stable and persistent infection and to block fleas. Similarly, none of the deletants caused any acute flea toxicity. In the mouse model of infection, all deletants were fully virulent upon subcutaneous or aerosol infections. Therefore

Corrosion protection products as a source of bisphenol A and toxicity to the aquatic environment.

Science.gov (United States)

Vermeirssen, Etiënne L M; Dietschweiler, Conrad; Werner, Inge; Burkhardt, Michael

2017-10-15

Steel components are typically treated with anti-corrosion coatings like epoxy or polyurethane resins to protect the integrity and functioning of steel. Such resins may contain substances, such as bisphenol A (BPA), that have caused concern in a human and environmental toxicological context. We investigated the release of toxicity from four anti-corrosion coatings used in hydraulic and civil engineering. Resins were applied onto glass plates and leachate samples produced by horizontally shaking the plates in water for 7 days. Two experiments were conducted, one with a 1 day and one with a 7 day curing period. Using a suite of bioassays, we tested samples for: agonistic and antagonistic effects on various mammalian nuclear receptors; inhibition of photosynthesis and growth in algae; inhibition of bacterial bioluminescence; and inhibition of water flea reproduction. Concentrations of BPA, bisphenol F and various BPA transformation products were determined by chemical analysis (LC-MS/MS). Bioassay results were evaluated using a scheme developed by DIBt (Centre of Competence for Construction, Berlin, Germany). Three products induced responses in one or more of the measured endpoints and toxicity profiles varied markedly in intensity across products. One product released high amounts of BPA which was associated with effects on nuclear receptor transactivation, requiring a more than 700-fold dilution for effect induction to fall below 20%. The same product was also the most toxic to water flea reproduction, requiring ca. 70-fold dilution for effects to fall below 20%. Another product was highly toxic in terms of bacterial bioluminescence, particularly after a shorter curing time, requiring a ca. 1'300-fold dilution for effects to fall below 20%. The third product required a 22-fold dilution for inhibition of water flea reproduction to drop below 20%. Results show that anti-corrosion coatings based on epoxy resins can be a source of toxicity to the aquatic environment

Parasites of sheep herding dogs in central Germany.

Science.gov (United States)

Rehbein, Steffen; Kaulfuß, Karl-heinz; Visser, Martin; Sommer, Maria Franziska; Grimm, Felix; Silaghi, Cornelia

2016-01-01

This paper reports on endoparasite infections diagnosed in 2012 by standard coproscopical techniques and coproantigen Giardia ELISA in 165 dogs used for sheep herding in 36 farms in central Germany. The overall prevalence of dogs with evidence of endoparasite infections was 27.3% (95% CI 20.6-34.7). The most frequently identified faecal forms were those of ascarids (Toxocara, 6.7%; Toxascaris 3.6%), hookworms (5.5%) and taeniid cestodes (4.2%), followed by those of Trichuris whipworms (3.0%), Capillaria aerophila (1.8%), Angiostrongylus and Crenosoma lungworms (1.2% each) and Cystoisospora canis coccidians (0.6%). Molecular identification demonstrated the seven dogs shedding taeniid eggs positive for Taenia (T.) species tapeworms (five, T. hydatigena; one, T. ovis; one Taenia sp.). Screening of the faeces with the coproantigen ELISA revealed Giardia specific antigen in 5.5% of the samples. The majority of the dogs had evidence of single endoparasite infections (22.4%) while evidence for infection with two or three parasites concurrently was found in six (3.6%) and two (1.2%) of the dogs, respectively. Dogs ≤ 1 year (n = 19) were parasitized more frequently (p < 0.05) with overall gastrointestinal parasites (63.2% vs. 20.5%), ascarids (36.8% vs. 6.8%) and Giardia spp. (21.1% vs. 3.4%) than older dogs (n = 146). Dogs which had been wormed within six months of examination tested less frequently positive for gastrointestinal helminths compared to dogs not wormed (11.1% vs. 25.0%; p = 0.0567). In addition, ear swabs taken from 43 sheep dogs in 2012 were examined, and Otodectes cynotis mites were extracted from one dog. Identification of ectoparasites collected by full body search and combing from 113 sheep dogs in the years 2011 to 2013 revealed infestation of fleas and ticks (each up to five specimens per dog) on 13 and 108 dogs, respectively, with nine dogs carrying both fleas and ticks. Archaeopsylla erinacei, Ctenocephalides (C) canis, C. felis and Pulex irritans

Diagnosis and therapeutic management of Dipylidium caninum in dogs: a case report

OpenAIRE

Saini, Vijesh Kumar; Gupta, Snehil; Kasondra, Arjun; Rakesh, R. L.; Latchumikanthan, A.

2016-01-01

The present study is related to Dipylidium caninum infection in dogs. Three dogs about 1 year of age with the history of scooting behaviour and passing diarrhoeic stool containing white specks were presented before the clinicians. Physical examination of dogs revealed flea infestation and faecal examination revealed the presence of gravid segments, which were confirmed microscopically to be of cestode, D. caninum. Dogs were treated with Praziquantel@5 mg/kg body wt. orally. Dogs showed marked...

A Risk Assessment of exposure to chlorpyrifos from foodstuff in the Slovak Republic

OpenAIRE

Šalgovičová, Danka

2012-01-01

Chlorpyrifos (O,O-diethyl-O-(3,5,6-trichlor-2-pyridyl)-phosphorothioate) is a white cristalline organophosphates with a broad-spectrum of insecticide effects. Chlorpyrifos is acrid and poor water soluble compound. In agriculture it is used for the treatment of infected leaves and the fruit as well as beet, maize, cereals, pepper, cucumbers and potatoes. It is effective for the destruction of mosquitoes, cockroaches, caterpillars, fleas, ants and other insects. Applying to the affected cr...

[Monitoring the Microtus fuscus plague epidemic in Sichuan province during 2000 - 2008.

DEFF Research Database (Denmark)

Wang, Li-Mao; Song, Xiao-Yu; Zhu, Xiao-Ping

2009-01-01

OBJECTIVE: To analyze the epidemic tendency of Microtus fuscus plague during 2000 - 2008 in Sichuan province. METHODS: To investigate the plague each year according to "overall Plan of the Plague in the Whole Nation" and "Surveillance Program of Sichuan Province Plague". RESULTS: There were plague...... of fleas, Callopsylla sparsilis, Amphipsylla tutua tutua and Rhadinopsylla dahurica vicina, with the overall infection rate as 0.054%. CONCLUSION: Plague among Microtus fuscus showed a continuous epidemic in Sichuan province during 2000 - 2008....

Growing in Motion: The Circulation of Used Things on Second-hand Markets

OpenAIRE

Staffan Appelgren; Anna Bohlin

2015-01-01

From having been associated with poverty and low status, the commerce with second-hand goods in retro shops, flea markets, vintage boutiques and trade via Internet is expanding in Sweden as in many countries in the Global North. This article argues that a significant aspect of the recent interest in second-hand and reuse concerns the meaning fulness of circulation in social life. Using classic anthropological theory on how the circulation of material culture generates sociality, it focuses on...

[Tungiasis affects a chilean turist].

Science.gov (United States)

Vergara M, Cristian; Barthel M, Elizabeth; Labarca M, Eduardo; Neira O, Patricia; Espinoza E, Roberto

2009-06-01

Tungiasis is a cutaneous ectoparasitosis caused by the female sand flea Tunga penetrans whose higher prevalence occurs in Sub-Saharan Africa, South América and the Caribbean. We report a case of a 23 year old chilean male who presented dermal lesions suggestive of tungiasis on his return from Brazil. The diagnosis was confirmed by biopsy, identifying the arthropod and an egg from one of the lesions. The natural history, co-morbidities and treatment options were reviewed.

Records of ectoparasites on humans and sheep from Viking-age deposits in the former western settlement of Greenland.

Science.gov (United States)

Sadler, J P

1990-07-01

During recent archaeological excavations in Viking Greenland, specimens of the human flea, Pulex irritans L., and the body louse, Pediculus humanus humanus L., were recovered from several farmsteads. Bovicola ovis (Schrank) and the sheep ked, Melophagus ovinus (L.), also were found in associated deposits. The specimens were dated from about AD 990 to AD 1350. These finds raise questions about the levels of hygiene of the Viking farmers and open some interesting medical and biogeographical conundrums.

Ectoparasites of the occult bat, Myotis occultus (Chiroptera: Vespertilionidae)

Science.gov (United States)

Valdez, Ernest W.; Ritzi, Christopher M.; Whitaker, John O.

2009-01-01

Only a single previous study has examined ectoparasites of the occult bat (Myotis occultus), from which only 2 species of fleas were identified. For our study, we examined 202 individuals, 52 fresh hosts and 150 museum specimens, from New Mexico and southern Colorado for ectoparasites. We recorded 2158 ectoparasites, 634 from fresh hosts and 1524 from museum specimens. Ectoparasites belonged to 10 families and 13 genera of insect or acari and represent new host and locality records. In general, ectoparasites collected from fresh hosts and museum specimens were represented by 4 major species of mite: Macronyssus crosbyi, Alabidocarpus calcaratus, Acanthophthirius lucifugus, and Alabidocarpus nr. eptesicus. From our study, we found fresh hosts to have significantly greater prevalence values for Myodopsylla gentilis (flea), Chiroptonyssus robustipes (mite), and Leptotrombidium myotis (chigger), whereas museum specimens had significantly greater prevalence values for A. calcaratus(mite) and A. nr. eptesicus (mite). There were no significant differences between prevalence values for 4 mites including M. crosbyi, A. lucifugus, Pteracarus nr. minutus, and Cryptonyssussp. Our study represents the only extensive study of ectoparasites on M. occultus and provides evidence for the importance of examining fresh hosts and museum specimens in future ectoparasite studies.

Invertebrate vectors, parasites, and rickettsial agents in Guam

Directory of Open Access Journals (Sweden)

Johnson, J.

2012-12-01

Full Text Available We conducted a 3-week field study of ectoparasites of humans and domestic animals throughout Guam. Thirteen species of ectoparasitic arthropods were collected. Ectoparasites of medical or veterinary significance included the ticks Rhipicephalus sanguineus and Rhipicephalus microplus, fleas Ctenocephalides felis and Xenopsylla cheopsis, and the head louse Pediculus humanus capitis. Polymerase chain reaction based screening for rickettsial and protozoan pathogens detected pathogens in eight arthropods. These included Anaplasma platys, Coxiella burnetii, Babesia canis vogeli, and Hepatozoon canis.

Myxomatosis in farmland rabbit populations in England and Wales.

OpenAIRE

Ross, J.; Tittensor, A. M.; Fox, A. P.; Sanders, M. F.

1989-01-01

The overall pattern and consequences of myxomatosis in wild rabbit populations were studied at three farmland sites in lowland southern England and upland central Wales between 1971 and 1978. When results from all years were combined, the disease showed a clear two-peaked annual cycle, with a main autumn peak between August and January, and a subsidiary spring peak during February to April. Rabbit fleas, the main vectors of myxomatosis in Britain, were present on full-grown rabbits in suffici...

1 Predicting small mammal and flea abundance using landform and ...

African Journals Online (AJOL)

Particle size distribution. pH. (H2O). OC. (%). CEC .... (Intercept). 20.889. 12.493. 1.67. 0.1075. Elevation (m). 0.0097. 0.005. 1.82. 0.0821 ... convergence and divergence of water flows, soil water content and soil water retention characteristics.

Illnesses on the Rise From Mosquito, Tick, and Flea Bites

Science.gov (United States)

... Done The Federal government is Funding states, territories, industry, university, and international groups to detect and respond ... and tents, with permethrin or buy permethrin-treated clothing and gear. Take steps to control ticks and ...

flea beetle populations and economic yield of okra as influenced

African Journals Online (AJOL)

Prof. Adipala Ekwamu

Aussi, il n'yavait pas eu de difference significative en terme d'interaction .... The study was carried out at the Teaching and ..... metabolic pathways especially when applied .... Journal of Plant Nutrition ... Annals of Botany 105 (2):333-339.

Empirical assessment of a threshold model for sylvatic plague

DEFF Research Database (Denmark)

Davis, Stephen; Leirs, Herwig; Viljugrein, H.

2007-01-01

Plague surveillance programmes established in Kazakhstan, Central Asia, during the previous century, have generated large plague archives that have been used to parameterize an abundance threshold model for sylvatic plague in great gerbil (Rhombomys opimus) populations. Here, we assess the model...... examine six hypotheses that could explain the resulting false positive predictions, namely (i) including end-of-outbreak data erroneously lowers the estimated threshold, (ii) too few gerbils were tested, (iii) plague becomes locally extinct, (iv) the abundance of fleas was too low, (v) the climate...

Mechanisms relevant to the enhanced virulence of a dihydroxynaphthalene-melanin metabolically engineered entomopathogen.

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Min-Nan Tseng

Full Text Available The entomopathogenic fungus Metarhizium anisopliae MA05-169 is a transformant strain that has been metabolically engineered to express dihydroxynaphthalene-melanin biosynthesis genes. In contrast to the wild type strain, the transformant displays a greater resistance to environmental stress and a higher virulence toward target insect host. However, the underlying mechanisms for these characteristics remain unclear; hence experiments were initiated to explore the possible mechanism(s through physiological and molecular approaches. Although both transformant and wild type strains could infect and share the same insect host range, the former germinated faster and produced more appressoria than the latter, both in vivo and in vitro. The transformant showed a significantly shorter median lethal time (LT50 when infecting the diamondback moth (Plutella xylostella and the striped flea beetle (Phyllotreta striolata, than the wild type. Additionally, the transformant was more tolerant to reactive oxygen species (ROS, produced 40-fold more orthosporin and notably overexpressed the transcripts of the pathogenicity-relevant hydrolytic enzymes (chitinase, protease, and phospholipase genes in vivo. In contrast, appressorium turgor pressure and destruxin A content were slightly decreased compared to the wild type. The transformant's high anti-stress tolerance, its high virulence against five important insect pests (cowpea aphid Aphis craccivora, diamondback moth Pl. xylostella, striped flea beetle Ph. striolata, and silverleaf whitefly Bemisia argentifolii and its capacity to colonize the root system are key properties for its potential bio-control field application.

[Human plague and pneumonic plague : pathogenicity, epidemiology, clinical presentations and therapy].

Science.gov (United States)

Riehm, Julia M; Löscher, Thomas

2015-07-01

Yersinia pestis is a highly pathogenic gram-negative bacterium and the causative agent of human plague. In the last 1500 years and during three dreaded pandemics, millions of people became victims of Justinian's plague, the Black Death, or modern plague. Today, Y. pestis is endemic in natural foci of Asian, African and American countries. Due to its broad dissemination in mammal species and fleas, eradication of the pathogen will not be possible in the near future. In fact, plague is currently classified as a "re-emerging disease". Infection may occur after the bite of an infected flea, but also after oral ingestion or inhalation of the pathogen. The clinical presentations comprise the bubonic and pneumonic form, septicemia, rarely pharyngitis, and meningitis. Most human cases can successfully be treated with antibiotics. However, the high transmission rate and lethality of pneumonic plague require international and mandatory case notification and quarantine of patients. Rapid diagnosis, therapy and barrier nursing are not only crucial for the individual patient but also for the prevention of further spread of the pathogen or of epidemics. Therefore, WHO emergency schedules demand the isolation of cases, identification and surveillance of contacts as well as control of zoonotic reservoir animals and vectors. These sanctions and effective antibiotic treatment usually allow a rapid containment of outbreaks. However, multiple antibiotic resistant strains of Y. pestis have been isolated from patients in the past. So far, no outbreaks with such strains have been reported.

Use of novel compounds for pest control: insecticidal and acaricidal activity of essential oil components from heartwood of Alaska yellow cedar.

Science.gov (United States)

Panella, Nicholas A; Dolan, Marc C; Karchesy, Joseph J; Xiong, Yeping; Peralta-Cruz, Javier; Khasawneh, Mohammad; Montenieri, John A; Maupin, Gary O

2005-05-01

Laboratory bioassays were conducted to determine the activity of 15 natural products isolated from essential oil components extracted from the heartwood of Alaska yellow cedar, Chamaecyparis nootkatensis (D. Don) Spach., against Ixodes scapularis Say nymphs, Xenopsylla cheopis (Rothchild), and Aedes aegypti (L.) adults. Four of the compounds from the essential oil have been identified as monoterpenes, five as eremophilane sesquiterpenes, five as eremophilane sesquiterpene derivatives from valencene and nootkatone, and one as a sesquiterpene outside the eremophilane parent group. Carvacrol was the only monoterpene that demonstrated biocidal activity against ticks, fleas, and mosquitoes with LC50 values after 24 h of 0.0068, 0.0059, and 0.0051% (wt:vol), respectively. Nootkatone from Alaska yellow cedar was the most effective of the eremophilane sesquiterpenes against ticks (LC50 = 0.0029%), whereas the nootkatone grapefruit extract exhibited the greatest biocidal activity against fleas (LC50 = 0.0029%). Mosquitoes were most susceptible to one of the derivatives of valencene, valencene-13-aldehyde (LC50 = 0.0024%), after 24 h. Bioassays to determine residual activity of the most effective products were conducted at 1, 2, 4, and 6 wk after initial treatment. Residual LC50 values for nootkatone did not differ significantly at 4 wk posttreatment from the observations made at the initial 24-h treatment. The ability of these natural products to kill arthropods at relatively low concentrations represents an alternative to the use of synthetic pesticides for control of disease vectors.

[The plague: An overview and hot topics].

Science.gov (United States)

Galy, A; Loubet, P; Peiffer-Smadja, N; Yazdanpanah, Y

2018-04-05

Plague is a bacterial zoonosis caused by Yersinia pestis, usually found in fleas and small rodents that constitute the reservoir of the disease. It is transmitted to humans by flea bite, contact with rodents or inhalation of infected droplets. There are three clinical forms: bubonic plague, pulmonary plague and septicemic plague. The usual presentation is a flu-like syndrome possibly accompanied by an inflammatory lymphadenopathy which appears after 1 to 7days of incubation. Bubonic plague has a case fatality rate of about 50% while other forms of plague are almost always fatal without treatment. Diagnosis can be confirmed by usual bacteriological techniques (Gram examination, culture) but also by serological examination, use of rapid diagnostic tests or PCR. Although aminoglycosides are traditionally regarded as the most effective treatment, fluoroquinolones or cyclins are currently recommended in France. Plague is one of the re-emerging diseases according to the WHO and Madagascar suffered in 2017 the most important plague epidemic of the 21st century with more than 2000 cases and 200 deaths. Peru and the Democratic Republic of Congo are also considered endemic areas. Public health measures and a relentless fight against poverty are the cornerstone of the control of the disease. Vaccine improvement in endemic areas may also play an important role. Copyright © 2018 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Factors Affecting the Consumer Purchasing Decisions of Perishable Foods: Exploring the Attitudes and the Preferences

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Muhammad Rehan MASOOM

2015-09-01

Full Text Available The present study is designed to make a comprehensive understanding of the attitude of the urban consumers and explore the factors involved in dealing with the perishable food of certain kinds. The rise of the middle class stipulates the enhancement of the shopping environment; hence witnessing a substantial increase of the number of the supermarkets in developing countries like Bangladesh will not be surprising. A number of urban supermarkets in recent times start selling perishable foods that were once available in Bangladesh only in flea markets (Kaccha Bazaar. However, due to the lack of proper infrastructure, agro-based perishable food reaches the urban market via a long process of chain mediations and raises concerns about quality and price for both retailers and consumers. Very often the attitudes of consumers regarding perishable foods are unknown and their preferences remain unidentified. This high level of uncertainty regarding the attitude of consumers and the unpopularity regarding overall food quality need to be resolved to ensure the continuity of the business and guarantee the quality of the products. This has made the study of the consumers’ attitude towards perishable food, especially relevant for emerging economies like Bangladesh. The data is collected from one hundred (100 consumers, who buy food regularly from both super-shops and flea markets in Dhaka city. The collected data are analyzed in terms of factors like importance, expectation and perceived actual level of value to show the gap in terms of perishable foods involved.

Level of awareness regarding some zoonotic diseases, among dog owners of ithaca, new york.

Science.gov (United States)

Sandhu, Gursimrat Kaur; Singh, Devinder

2014-01-01

Worldwide, dogs and cats are the two most common household companion animals. Because of this, they can be direct or indirect source of many human infections. Fortunately, most of these zoonotic infections can be clinically prevented by appropriate prophylactic interventions. Present kind of cross-sectional study, for the first time, was conducted in city of Ithaca, New York. People visiting local animal hospitals, dog parks, library and shoppers at Walmart supermarket were personally interviewed and a pre-tested questionnaire was got filled from every individual. The collected data were analyzed for percentage proportions using Microsoft Excel(®) and the results had been presented in graphical as well as tabulated forms. Out of 100 participants responding to the request for participation, gender-wise, 45% of the participants were male while 55% of the participants were females. Demographically, 50% participants lived in rural, 35% in urban while 15% participants lived in suburban areas. Educational background of the participants ranged from High school pass-outs to Graduates. Participants were aware about the zoonotic potential of leptospirosis, giardiasis, rabies, hookworms, coccidiosis, lyme disease, roundworms, toxoplasma, leishmaniasis, salmonellosis and ringworm disease. Knowledge gaps in the sampled population, in terms of lack of awareness about zoonotic diseases vectored by mosquitoes, ticks and fleas; practice of not doing regular deworming and prophylactic control of fleas and ticks on pet dogs; and lack of practice among physicians to discuss zoonotic canine diseases with their clients were revealed by this study.

Chemical and ecological control methods for Epitrix spp.

Directory of Open Access Journals (Sweden)

A. G. S. Cuthbertson

2015-01-01

Full Text Available Very little information exists in regards to the control options available for potato flea beetles, Epitrix spp. This short review covers both chemical and ecological options currently available for control of Epitrix spp. Synthetic pyrethroids are the weapon of choice for the beetles. However, the impetus in integrated pest management is to do timely (early-season applications with something harsh which will give long-term protection at a time when there are not a lot of beneficials in the field. Finding the balance for control of Epitrix spp. is proving difficult.

Roman Lyariev, How to Skin Your Kill

OpenAIRE

Gedeeva, Darina; Ubushieva, Bamba; Babaev, Andrei

2016-01-01

Roman explains how to skin a fox. First, one needs to prepare the ground by trampling it. Skinning should be done with a small sharp knife. A freshly killed fox skins easily. Then one needs to treat the skin with an anti-flea spray. At home the skin should be stretched on a triangular wooden panel called in Russian pravilka and left in a dry room for up to five days. People usually go hunting when foxes are on heat and are busy fighting with each other for females. When the wind is strong, fo...

Tungiasis: a case report and review of the literature

Directory of Open Access Journals (Sweden)

Chieh-Wen Chen

2011-03-01

Full Text Available Tungiasis is a cutaneous parasitic infection caused by the sand flea Tunga penetrans. This infection is endemic to Central and South America, the Caribbean, and sub-Saharan Africa and is more prevalent in resource-poor communities. Increased air travel, emigration from, and immigration to these countries can lead to the import of T. penetrans to travelers’ hometowns. In recent times, dermatologists have encountered many such tropical cutaneous infections, and they should promptly diagnose the condition to prevent complications. We report a case of tungiasis imported from Brazil and review the related literature.

[Natural focus of tularemia on the Kerchen peninsula (Crimea)].

Science.gov (United States)

Golkovskiĭ, G M; Mitsevich, G F; Khaĭtovich, A B; Alekseev, E V; Korchevskiĭ, P G

1981-10-01

The study confirming the existence of the steppe-type natural focus of tularemia on the Kerch peninsula has been carried out. For the first time the cultures of Francisella tularensis have been isolated. Voles and house mice play the main role in the circulation of the infection. The parasitic system comprises ticks (Ixodidae and Nyalomma), as well as some species of fleas. In carrying out erizootological studies for detecting tularemia in the Crimea the use of low temperature (0 degrees C) for the preservation of specimens and preparations in recommended.

Photoperiodism of Male Offspring Production in the Water Flea Daphnia pulex.

Science.gov (United States)

Toyota, Kenji; Sato, Tomomi; Tatarazako, Norihisa; Iguchi, Taisen

2017-08-01

Photoperiodism is a biological seasonal timing system utilized to regulate development and reproduction in organisms. The freshwater micro-crustacean Daphnia pulex displays environmental sex determination, the precise physiological mechanisms of which are largely unknown due to the lack of an experimental system to induce female or male offspring production by alterations of the rearing environment. We recently found that D. pulex, WTN6 strain, produces female or male offspring in response to long-day or short-day conditions, respectively. Taking advantage of this system, here we report the photoperiodic response curve for male offspring production, showing 12 hours as natural critical daylength (50% incidence of male-producing mothers), and that male offspring inducibility is highly sensitive to photoperiodic alterations. By using monochromatic light emitting diode (LED) devices, we found that the effective wavelength is red-light (627 nm), which stably induces male offspring production. This suggests that the red-light photoreceptor may be decisive in the primary step of sex determination process in this strain. Our findings provide the first insights into photoperiodism and red-light as key factors in triggering male offspring production in daphnids.

Mechanism study on a plague outbreak driven by the construction of a large reservoir in southwest china (surveillance from 2000-2015.

Directory of Open Access Journals (Sweden)

Xin Wang

2017-03-01

Full Text Available Plague, a Yersinia pestis infection, is a fatal disease with tremendous transmission capacity. However, the mechanism of how the pathogen stays in a reservoir, circulates and then re-emerges is an enigma.We studied a plague outbreak caused by the construction of a large reservoir in southwest China followed 16-years' surveillance.The results show the prevalence of plague within the natural plague focus is closely related to the stability of local ecology. Before and during the decade of construction the reservoir on the Nanpan River, no confirmed plague has ever emerged. With the impoundment of reservoir and destruction of drowned farmland and vegetation, the infected rodent population previously dispersed was concentrated together in a flood-free area and turned a rest focus alive. Human plague broke out after the enzootic plague via the flea bite. With the construction completed and ecology gradually of human residential environment, animal population and type of vegetation settling down to a new balance, the natural plague foci returned to a rest period. With the rodent density decreased as some of them died, the flea density increased as the rodents lived near or in local farm houses where had more domestic animals, and human has a more concentrated population. In contrast, in the Himalayan marmot foci of the Qinghai-Tibet Plateau in the Qilian Mountains. There are few human inhabitants and the local ecology is relatively stable; plague is prevalence, showing no rest period. Thus the plague can be significantly affected by ecological shifts.

Fur is a repressor of biofilm formation in Yersinia pestis.

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Fengjun Sun

Full Text Available BACKGROUND: Yersinia pestis synthesizes the attached biofilms in the flea proventriculus, which is important for the transmission of this pathogen by fleas. The hmsHFRS operons is responsible for the synthesis of exopolysaccharide (the major component of biofilm matrix, which is activated by the signaling molecule 3', 5'-cyclic diguanylic acid (c-di-GMP synthesized by the only two diguanylate cyclases HmsT, and YPO0449 (located in a putative operonYPO0450-0448. METHODOLOGY/PRINCIPAL FINDINGS: The phenotypic assays indicated that the transcriptional regulator Fur inhibited the Y. pestis biofilm production in vitro and on nematode. Two distinct Fur box-like sequences were predicted within the promoter-proximal region of hmsT, suggesting that hmsT might be a direct Fur target. The subsequent primer extension, LacZ fusion, electrophoretic mobility shift, and DNase I footprinting assays disclosed that Fur specifically bound to the hmsT promoter-proximal region for repressing the hmsT transcription. In contrast, Fur had no regulatory effect on hmsHFRS and YPO0450-0448 at the transcriptional level. The detection of intracellular c-di-GMP levels revealed that Fur inhibited the c-di-GMP production. CONCLUSIONS/SIGNIFICANCE: Y. pestis Fur inhibits the c-di-GMP production through directly repressing the transcription of hmsT, and thus it acts as a repressor of biofilm formation. Since the relevant genetic contents for fur, hmsT, hmsHFRS, and YPO0450-0448 are extremely conserved between Y. pestis and typical Y. pseudotuberculosis, the above regulatory mechanisms can be applied to Y. pseudotuberculosis.

Mechanism study on a plague outbreak driven by the construction of a large reservoir in southwest china (surveillance from 2000-2015).

Science.gov (United States)

Wang, Xin; Wei, Xiaoyu; Song, Zhizhong; Wang, Mingliu; Xi, Jinxiao; Liang, Junrong; Liang, Yun; Duan, Ran; Tian, Kecheng; Zhao, Yong; Tang, Guangpeng; You, Lv; Yang, Guirong; Liu, Xuebin; Chen, Yuhuang; Zeng, Jun; Wu, Shengrong; Luo, Shoujun; Qin, Gang; Hao, Huijing; Jing, Huaiqi

2017-03-01

Plague, a Yersinia pestis infection, is a fatal disease with tremendous transmission capacity. However, the mechanism of how the pathogen stays in a reservoir, circulates and then re-emerges is an enigma. We studied a plague outbreak caused by the construction of a large reservoir in southwest China followed 16-years' surveillance. The results show the prevalence of plague within the natural plague focus is closely related to the stability of local ecology. Before and during the decade of construction the reservoir on the Nanpan River, no confirmed plague has ever emerged. With the impoundment of reservoir and destruction of drowned farmland and vegetation, the infected rodent population previously dispersed was concentrated together in a flood-free area and turned a rest focus alive. Human plague broke out after the enzootic plague via the flea bite. With the construction completed and ecology gradually of human residential environment, animal population and type of vegetation settling down to a new balance, the natural plague foci returned to a rest period. With the rodent density decreased as some of them died, the flea density increased as the rodents lived near or in local farm houses where had more domestic animals, and human has a more concentrated population. In contrast, in the Himalayan marmot foci of the Qinghai-Tibet Plateau in the Qilian Mountains. There are few human inhabitants and the local ecology is relatively stable; plague is prevalence, showing no rest period. Thus the plague can be significantly affected by ecological shifts.

A bibliography of literature pertaining to plague (Yersinia pestis)

Science.gov (United States)

Ellison, Laura E.; Frank, Megan K. Eberhardt

2011-01-01

Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis. Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis, management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google (http://www.google.com), Google Scholar (http://scholar.google.com), SciVerse Scopus (http://www.scopus.com), ISI Web of Knowledge (http://apps.isiknowledge.com), and the USGS Library's Digital Desktop (http://library.usgs.gov). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.

Tularemia and plague survey in rodents in an earthquake zone in southeastern Iran

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Gyuranecz, Miklós

2015-01-01

OBJECTIVES: Earthquakes are one the most common natural disasters that lead to increased mortality and morbidity from transmissible diseases, partially because the rodents displaced by an earthquake can lead to an increased rate of disease transmission. The aim of this study was to evaluate the prevalence of plague and tularemia in rodents in the earthquake zones in southeastern Iran. METHODS: In April 2013, a research team was dispatched to explore the possible presence of diseases in rodents displaced by a recent earthquake magnitude 7.7 around the cities of Khash and Saravan in Sistan and Baluchestan Province. Rodents were trapped near and in the earthquake zone, in a location where an outbreak of tularemia was reported in 2007. Rodent serums were tested for a serological survey using an enzyme-linked immunosorbent assay. RESULTS: In the 13 areas that were studied, nine rodents were caught over a total of 200 trap-days. Forty-eight fleas and 10 ticks were obtained from the rodents. The ticks were from the Hyalomma genus and the fleas were from the Xenopsylla genus. All the trapped rodents were Tatera indica. Serological results were negative for plague, but the serum agglutination test was positive for tularemia in one of the rodents. Tatera indica has never been previously documented to be involved in the transmission of tularemia. CONCLUSIONS: No evidence of the plague cycle was found in the rodents of the area, but evidence was found of tularemia infection in rodents, as demonstrated by a positive serological test for tularemia in one rodent. PMID:26602769

Recent speciation in three closely related sympatric specialists: inferences using multi-locus sequence, post-mating isolation and endosymbiont data.

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Huai-Jun Xue

Full Text Available Shifting between unrelated host plants is relatively rare for phytophagous insects, and distinct host specificity may play crucial roles in reproductive isolation. However, the isolation status and the relationship between parental divergence and post-mating isolation among closely related sympatric specialists are still poorly understood. Here, multi-locus sequence were used to estimate the relationship among three host plant-specific closely related flea beetles, Altica cirsicola, A. fragariae and A. viridicyanea (abbreviated as AC, AF and AV respectively. The tree topologies were inconsistent using different gene or different combinations of gene fragments. The relationship of AF+(AC+AV was supported, however, by both gene tree and species tree based on concatenated data. Post-mating reproductive data on the results of crossing these three species are best interpreted in the light of a well established phylogeny. Nuclear-induced but not Wolbachia-induced unidirectional cytoplasmic incompatibility, which was detected in AC-AF and AF-AV but not in AC-AV, may also suggest more close genetic affinity between AC and AV. Prevalence of Wolbachia in these three beetles, and the endosymbiont in most individuals of AV and AC sharing a same wsp haplotype may give another evidence of AF+(AC+AV. Our study also suggested that these three flea beetles diverged in a relative short time (0.94 My, which may be the result of shifting between unrelated host plants and distinct host specificity. Incomplete post-mating isolation while almost complete lineage sorting indicated that effective pre-mating isolation among these three species should have evolved.

Black-footed ferrets and recreational shooting influence the attributes of black-tailed prairie dog burrows

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Biggins, Dean E.; Ramakrishnan, Shantini; Goldberg, Amanda R.; Eads, David A.

2012-01-01

Black-tailed prairie dogs (Cynomys ludovicianus) plug burrows occupied by black-footed ferrets (Mustela nigripes), and they also plug burrows to entomb dead prairie dogs. We further evaluated these phenomena by sampling connectivity and plugging of burrow openings on prairie dog colonies occupied by ferrets, colonies where recreational shooting was allowed, and colonies with neither shooting nor ferrets. We counted burrow openings on line surveys and within plots, classified surface plugging, and used an air blower to examine subsurface connectivity. Colonies with ferrets had lower densities of openings, fewer connected openings (suggesting increased subsurface plugging), and more surface plugs compared to colonies with no known ferrets. Colonies with recreational shooting had the lowest densities of burrow openings, and line-survey data suggested colonies with shooting had intermediate rates of surface plugging. The extent of surface and subsurface plugging could have consequences for the prairie dog community by changing air circulation and escape routes of burrow systems and by altering energetic relationships. Burrow plugging might reduce prairie dogs' risk of predation by ferrets while increasing risk of predation by American badgers (Taxidea taxus); however, the complexity of the trade-off is increased if plugging increases the risk of predation on ferrets by badgers. Prairie dogs expend more energy plugging and digging when ferrets or shooting are present, and ferrets increase their energy expenditures when they dig to remove those plugs. Microclimatic differences in plugged burrow systems may play a role in flea ecology and persistence of the flea-borne bacterium that causes plague (Yersinia pestis).

Level of awareness regarding some zoonotic diseases, among dog owners of Ithaca, New York

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Gursimrat Kaur Sandhu

2014-01-01

Full Text Available Objectives: Worldwide, dogs and cats are the two most common household companion animals. Because of this, they can be direct or indirect source of many human infections. Fortunately, most of these zoonotic infections can be clinically prevented by appropriate prophylactic interventions. Materials and Methods: Present kind of cross-sectional study, for the first time, was conducted in city of Ithaca, New York. People visiting local animal hospitals, dog parks, library and shoppers at Walmart supermarket were personally interviewed and a pre-tested questionnaire was got filled from every individual. The collected data were analyzed for percentage proportions using Microsoft Excel ® and the results had been presented in graphical as well as tabulated forms. Results: Out of 100 participants responding to the request for participation, gender-wise, 45% of the participants were male while 55% of the participants were females. Demographically, 50% participants lived in rural, 35% in urban while 15% participants lived in suburban areas. Educational background of the participants ranged from High school pass-outs to Graduates. Conclusions: Participants were aware about the zoonotic potential of leptospirosis, giardiasis, rabies, hookworms, coccidiosis, lyme disease, roundworms, toxoplasma, leishmaniasis, salmonellosis and ringworm disease. Knowledge gaps in the sampled population, in terms of lack of awareness about zoonotic diseases vectored by mosquitoes, ticks and fleas; practice of not doing regular deworming and prophylactic control of fleas and ticks on pet dogs; and lack of practice among physicians to discuss zoonotic canine diseases with their clients were revealed by this study.

Diagnosis and therapeutic management of Dipylidium caninum in dogs: a case report.

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Saini, Vijesh Kumar; Gupta, Snehil; Kasondra, Arjun; Rakesh, R L; Latchumikanthan, A

2016-12-01

The present study is related to Dipylidium caninum infection in dogs. Three dogs about 1 year of age with the history of scooting behaviour and passing diarrhoeic stool containing white specks were presented before the clinicians. Physical examination of dogs revealed flea infestation and faecal examination revealed the presence of gravid segments, which were confirmed microscopically to be of cestode, D. caninum. Dogs were treated with Praziquantel@5 mg/kg body wt. orally. Dogs showed marked recovery post treatment. On re-examination after a week, faeces were found negative for any parasitic eggs/gravid segments.

An Ectopic Case of Tunga spp. Infection in Peru

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Maco, Vicente; Maco, Vicente P.; Gotuzzo, Eduardo

2010-01-01

Tungiasis is a neglected ectoparasitism of impoverished areas in South America and sub-Saharan Africa. The sand flea Tunga spp. preferably infests the soles and the periungueal and interdigital regions of the feet. Ectopic tungiasis is rare, even in highly endemic areas. We describe a case of an indigenous patient in Peru who presented with a nodular lesion in the extensor aspect of the knee and whose biopsy was compatible with Tunga spp. This is the first documented case of knee tungiasis in an endemic country. The historical, clinical, histological, and current epidemiological aspects of tungiasis in Peru are discussed here. PMID:20519602

Identification of mast cells in buffy coat preparations from dogs with inflammatory skin diseases.

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Cayatte, S M; McManus, P M; Miller, W H; Scott, D W

1995-02-01

In 100 dogs with 4 inflammatory dermatologic diseases, buffy coat preparations from EDTA-treated blood samples were examined cytologically. Fifty-four dogs had atopy, 26 had flea-bite hypersensitivity, 17 had sarcoptic mange, and 3 had food allergy. Twenty-eight dogs had 2 or more concurrent skin diseases; most of these had secondary pyoderma. Dogs did not have mast cell tumors. Thirteen samples contained 1 or more mast cells/4 slides reviewed. This study revealed that dogs with inflammatory skin diseases can have a few to many mast cells evident on cytologic examination of buffy coat preparations.

PENYAKIT BERSUMBER RODENSIA (TIKUS DAN MENCIT DI INDONESIA

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Ima Nurisa

2012-11-01

Full Text Available This is an attempt to make a list of some zoonotic diseases transmitted from rodents to man reported in Indonesia. The diseases may cause by all agents of disease i.e viruses, rickettsias, bacterias, protozoas, fungi or helminthes and transmit directly by contact/biting of rodent or indirectly by ectoparasite vectors such as lice, fleas, ticks or mites. The diseases reviewed are Hantavirus infection (hemorrhagic fever with renal syndrome = HFRS, rickettsiosis (scrub typhus, murine typhus and spotted fever group(SFG Rickettsiae plague, leptospirosis, salmonellosis, schistosomiasis, eosinophylic meningitis (angiostrongyliosis and echinostomiasis. Keywords: small mammals, zoonotic diseases, rodent, Indonesia

Cutaneous Hypersensitivity Dermatoses in the Feline Patient: A Review of Allergic Skin Disease in Cats

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Alison Diesel

2017-05-01

Full Text Available Feline allergic skin disease presents a unique set of challenges to the veterinary practitioner. Although there is some similarity to what is seen in the allergic canine patient, cutaneous hypersensitivity dermatoses in cats can manifest with strikingly different clinical signs, treatment options and outcomes, and secondary complications/disease entities. Additionally, less is known about the pathogenesis of feline allergic skin diseases, particularly “feline atopic syndrome” when compared to dogs or people. This article aims to review what is currently known in regards to allergic skin disease in the feline patient, with focus on non-flea, non-food hypersensitivity dermatitis.

Cutaneous Hypersensitivity Dermatoses in the Feline Patient: A Review of Allergic Skin Disease in Cats.

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Diesel, Alison

2017-05-09

Feline allergic skin disease presents a unique set of challenges to the veterinary practitioner. Although there is some similarity to what is seen in the allergic canine patient, cutaneous hypersensitivity dermatoses in cats can manifest with strikingly different clinical signs, treatment options and outcomes, and secondary complications/disease entities. Additionally, less is known about the pathogenesis of feline allergic skin diseases, particularly "feline atopic syndrome" when compared to dogs or people. This article aims to review what is currently known in regards to allergic skin disease in the feline patient, with focus on non-flea, non-food hypersensitivity dermatitis.

Vectors of rickettsiae in Africa.

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Bitam, Idir

2012-12-01

Vector-borne diseases are caused by parasites, bacteria, or viruses transmitted by the bites of hematophagous arthropods. In Africa, there has been a recent emergence of new diseases and the re-emergence of existing diseases, usually with changes in disease epidemiology (e.g., geographical distribution, prevalence, and pathogenicity). In Africa, rickettsioses are recognized as important emerging vector-borne infections in humans. Rickettsial diseases are transmitted by different types of arthropods, ticks, fleas, lice, and mites. This review will examine the roles of these different arthropod vectors and their geographical distributions. Copyright © 2012 Elsevier GmbH. All rights reserved.

1 Contribution of land use to rodent flea load distribution in the ...

African Journals Online (AJOL)

These findings suggest that land use factors have a major influence .... existence of outliers, normality and homogeneity was carried out (Zuur et al., 2010). ..... Laudisoit, A., Neerinckx, S., Makundi, R.H., Leirs, H. & Krasnov, B. (2009b) Are local ...

Ionotropic glutamate receptors mediate inducible defense in the water flea Daphnia pulex.

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Hitoshi Miyakawa

Full Text Available Phenotypic plasticity is the ability held in many organisms to produce different phenotypes with a given genome in response to environmental stimuli, such as temperature, nutrition and various biological interactions. It seems likely that environmental signals induce a variety of mechanistic responses that influence ontogenetic processes. Inducible defenses, in which prey animals alter their morphology, behavior and/or other traits to help protect against direct or latent predation threats, are among the most striking examples of phenotypic plasticity. The freshwater microcrustacean Daphnia pulex forms tooth-like defensive structures, "neckteeth," in response to chemical cues or signals, referred to as "kairomones," in this case released from phantom midge larvae, a predator of D. pulex. To identify factors involved in the reception and/or transmission of a kairomone, we used microarray analysis to identify genes up-regulated following a short period of exposure to the midge kairomone. In addition to identifying differentially expressed genes of unknown function, we also found significant up-regulation of genes encoding ionotropic glutamate receptors, which are known to be involved in neurotransmission in many animal species. Specific antagonists of these receptors strongly inhibit the formation of neckteeth in D. pulex, although agonists did not induce neckteeth by themselves, indicating that ionotropic glutamate receptors are necessary but not sufficient for early steps of neckteeth formation in D. pulex. Moreover, using co-exposure of D. pulex to antagonists and juvenile hormone (JH, which physiologically mediates neckteeth formation, we found evidence suggesting that the inhibitory effect of antagonists is not due to direct inhibition of JH synthesis/secretion. Our findings not only provide a candidate molecule required for the inducible defense response in D. pulex, but also will contribute to the understanding of complex mechanisms underlying the recognition of environmental changes, which form the basis of phenotypic plasticity.

Evaluation of the Role of the opgGH Operon in Yersinia pseudotuberculosis and Its Deletion during the Emergence of Yersinia pestis

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Quintard, Kévin; Dewitte, Amélie; Reboul, Angéline; Madec, Edwige; Bontemps-Gallo, Sébastien; Dondeyne, Jacqueline; Marceau, Michaël; Simonet, Michel

2015-01-01

The opgGH operon encodes glucosyltransferases that synthesize osmoregulated periplasmic glucans (OPGs) from UDP-glucose, using acyl carrier protein (ACP) as a cofactor. OPGs are required for motility, biofilm formation, and virulence in various bacteria. OpgH also sequesters FtsZ in order to regulate cell size according to nutrient availability. Yersinia pestis (the agent of flea-borne plague) lost the opgGH operon during its emergence from the enteropathogen Yersinia pseudotuberculosis. When expressed in OPG-negative strains of Escherichia coli and Dickeya dadantii, opgGH from Y. pseudotuberculosis restored OPGs synthesis, motility, and virulence. However, Y. pseudotuberculosis did not produce OPGs (i) under various growth conditions or (ii) when overexpressing its opgGH operon, its galUF operon (governing UDP-glucose), or the opgGH operon or Acp from E. coli. A ΔopgGH Y. pseudotuberculosis strain showed normal motility, biofilm formation, resistance to polymyxin and macrophages, and virulence but was smaller. Consistently, Y. pestis was smaller than Y. pseudotuberculosis when cultured at ≥37°C, except when the plague bacillus expressed opgGH. Y. pestis expressing opgGH grew normally in serum and within macrophages and was fully virulent in mice, suggesting that small cell size was not advantageous in the mammalian host. Lastly, Y. pestis expressing opgGH was able to infect Xenopsylla cheopis fleas normally. Our results suggest an evolutionary scenario whereby an ancestral Yersinia strain lost a factor required for OPG biosynthesis but kept opgGH (to regulate cell size). The opgGH operon was presumably then lost because OpgH-dependent cell size control became unnecessary. PMID:26150539

Evaluation of the Role of the opgGH Operon in Yersinia pseudotuberculosis and Its Deletion during the Emergence of Yersinia pestis.

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Quintard, Kévin; Dewitte, Amélie; Reboul, Angéline; Madec, Edwige; Bontemps-Gallo, Sébastien; Dondeyne, Jacqueline; Marceau, Michaël; Simonet, Michel; Lacroix, Jean-Marie; Sebbane, Florent

2015-09-01

The opgGH operon encodes glucosyltransferases that synthesize osmoregulated periplasmic glucans (OPGs) from UDP-glucose, using acyl carrier protein (ACP) as a cofactor. OPGs are required for motility, biofilm formation, and virulence in various bacteria. OpgH also sequesters FtsZ in order to regulate cell size according to nutrient availability. Yersinia pestis (the agent of flea-borne plague) lost the opgGH operon during its emergence from the enteropathogen Yersinia pseudotuberculosis. When expressed in OPG-negative strains of Escherichia coli and Dickeya dadantii, opgGH from Y. pseudotuberculosis restored OPGs synthesis, motility, and virulence. However, Y. pseudotuberculosis did not produce OPGs (i) under various growth conditions or (ii) when overexpressing its opgGH operon, its galUF operon (governing UDP-glucose), or the opgGH operon or Acp from E. coli. A ΔopgGH Y. pseudotuberculosis strain showed normal motility, biofilm formation, resistance to polymyxin and macrophages, and virulence but was smaller. Consistently, Y. pestis was smaller than Y. pseudotuberculosis when cultured at ≥ 37°C, except when the plague bacillus expressed opgGH. Y. pestis expressing opgGH grew normally in serum and within macrophages and was fully virulent in mice, suggesting that small cell size was not advantageous in the mammalian host. Lastly, Y. pestis expressing opgGH was able to infect Xenopsylla cheopis fleas normally. Our results suggest an evolutionary scenario whereby an ancestral Yersinia strain lost a factor required for OPG biosynthesis but kept opgGH (to regulate cell size). The opgGH operon was presumably then lost because OpgH-dependent cell size control became unnecessary. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Feline dermatology at Cornell University: 1407 cases (1988-2003).

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Scott, Danny W; Miller, William H; Erb, Hollis N

2013-04-01

Medical records of 1407 cats with dermatologic diagnoses made at Cornell University teaching hospital from 1988 to 2003 were tabulated. We expressed the diagnoses as counts, percentages of the cats with dermatologic disease (1407) and percentages of all cats seen at the university hospital (22,135) during the same period. A total of 1887 diagnoses were made in the 1407 cats. We compared the age, sex and breed group of our cases with all those 22,135 cats in ('1-by-c') χ(2) tests in which the hospital population was considered a standard (rather than a 'sample'). The 10 most common dermatoses, their counts, and the proportions of dermatologic diagnoses and of the total cat population that the cats with these dermatoses represented were: allergy (298; 15.8%; 1.35%), atopic dermatitis (194; 10.3%; 0.88%), bacterial folliculitis/furunculosis (189; 10.0%; 0.85%), otodectic mange (115; 6.1%; 0.52%), flea infestation (99; 5.2%; 0.45%), feline acne (74; 3.9%; 0.33%), flea-bite allergy (70; 3.7%; 0.32%), cutaneous adverse drug reaction (56; 3.0%; 0.25%), idiopathic eosinophilic-granuloma complex (55; 2.9%; 0.25%) and abscess (51; 2.7%; 0.23%). Allergies of all types, combined, accounted for 32.7% of all the feline dermatoses. Relative to the standard of the total hospital population, cats <2 years old and females (both intact and spayed) were significantly under-represented (all P≤0.001) in the dermatologic case series. In contrast, Himalayans (compared with domestic short- or longhair, Persian, Siamese and other breeds) and males (both intact and neutered) were significantly over-represented (all P ≤0.001).

Feline atopic dermatitis: a retrospective study of 45 cases (2001-2012).

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Ravens, Philippa A; Xu, Bei J; Vogelnest, Linda J

2014-04-01

Atopic dermatitis (AD) is recognized as a common cause of pruritus in cats, but it remains incompletely characterized. The aim of the study was to evaluate cases of confirmed feline AD. Fourty-five cats from a dermatology referral practice (2001-2012). A retrospective case record review was carried out using strict diagnostic criteria, including exclusion of flea-bite hypersensitivity and adverse food reaction. Disease prevalence was 12.5%, with domestic mixed (n = 24), Abyssinian (n = 6) and Devon rex (n = 3) cat breeds predisposed. Median age of onset was 2 years (62% 7 years; range 3 months to 12 years). Common presentations were severe (82%), nonseasonal (82%), waxing/waning (36%) pruritus, with alopecia/crusting/excoriations and/or erosions/ulceration (73%). Miliary dermatitis (20%) and eosinophilic granuloma complex lesions (27%) occurred. The face/head (71%), ventral abdomen (51%), neck (51%), limbs (38%), pinnae (31%), dorsum/rump (31%) and feet (16%) were frequently affected sites; lesions were restricted to the head/neck in only five cats (11%). Concurrent otitis externa (16%), superficial bacterial pyoderma (49%), Malassezia dermatitis (7%), flea-bite hypersensitivity (24%) and adverse food reaction (13%) occurred. Strong reactions on intradermal allergen testing were common (68%; 19 of 30), most frequently to pollens (61%) and/or insects (46%). Good response to ciclosporin (100%; 10 of 10), systemic glucocorticoids (55%; 22 of 40) and allergen-specific immunotherapy (57%; 13 of 23) and good/partial response to antihistamines (67%; 22 of 33) were reported. The prevalence of feline AD was higher than previously suggested, and breed predispositions were confirmed. Severe nonseasonal pruritus was most common, with a varied spectrum of lesions affecting a range of body areas. © 2014 ESVD and ACVD.

Patterns of Abundance and Host Specificity of Bat Ectoparasites in the Central Balkans.

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Burazerovic, J; Orlova, M; Obradovic, M; Cirovic, D; Tomanovic, S

2018-01-10

Bats are hosts to a number of ectoparasites-acarines (ticks, chiggers, other mites), bat flies, and fleas. Bat ectoparasites might have significant ecological and public health importance as they may be potential vectors of zoonotic agents. It is important to identify their distribution, diversity, and host-parasite associations. Bat ectoparasites in the central Balkans have been largely understudied. The present research was conducted in 45 localities at the territory of Bosnia and Herzegovina, former Yugoslav Republic of Macedonia, Montenegro, and Serbia. In total, 1,143 individuals of 18 species of bats have been examined for the presence and abundance of ectoparasite species during 3 yr of research. In total, 21 ectoparasite species have been identified: three species of ticks, seven species of mites (including one species of chigger), eight species of bat flies, and three species of fleas. In total, 80 host-parasite associations have been identified. The largest number of ectoparasites parasitized primarily only one host species. The highest total number of hosts was identified for ectoparasite species Ixodes vespertilionis Koch, Nycteribia schmidlii Schiner, and Spinturnix myoti Kolenati. The spinturnicid mite Spinturnix psi Kolenati was the most abundant ectoparasite species and together with Penicilidia dufouri Westwood the most widely distributed species of bat ectoparasite, being present at 21 localities in the central Balkans. The presented data include the first systematic records of patterns of prevalence, mean intensity, mean abundance, and host specificity for bat ectoparasites in the central Balkans. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Rapid evolution leads to differential population dynamics and top-down control in resurrected Daphnia populations.

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Goitom, Eyerusalem; Kilsdonk, Laurens J; Brans, Kristien; Jansen, Mieke; Lemmens, Pieter; De Meester, Luc

2018-01-01

There is growing evidence of rapid genetic adaptation of natural populations to environmental change, opening the perspective that evolutionary trait change may subsequently impact ecological processes such as population dynamics, community composition, and ecosystem functioning. To study such eco-evolutionary feedbacks in natural populations, however, requires samples across time. Here, we capitalize on a resurrection ecology study that documented rapid and adaptive evolution in a natural population of the water flea Daphnia magna in response to strong changes in predation pressure by fish, and carry out a follow-up mesocosm experiment to test whether the observed genetic changes influence population dynamics and top-down control of phytoplankton. We inoculated populations of the water flea D. magna derived from three time periods of the same natural population known to have genetically adapted to changes in predation pressure in replicate mesocosms and monitored both Daphnia population densities and phytoplankton biomass in the presence and absence of fish. Our results revealed differences in population dynamics and top-down control of algae between mesocosms harboring populations from the time period before, during, and after a peak in fish predation pressure caused by human fish stocking. The differences, however, deviated from our a priori expectations. An S-map approach on time series revealed that the interactions between adults and juveniles strongly impacted the dynamics of populations and their top-down control on algae in the mesocosms, and that the strength of these interactions was modulated by rapid evolution as it occurred in nature. Our study provides an example of an evolutionary response that fundamentally alters the processes structuring population dynamics and impacts ecosystem features.

Systemic insecticides used in dogs: potential candidates for phlebotomine vector control?

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Gomez, Sonia Ares; Picado, Albert

2017-06-01

Zoonotic visceral leishmaniasis (ZVL) is a public health problem endemic in some countries. Current control measures, in particular culling infected dogs, have not reduced ZVL incidence in humans. We evaluated the use of five systemic insecticides (spinosad, fluralaner, afoxolaner, sarolaner and moxidectin) currently used in dogs for other purposes (e.g. tick, flea control) in controlling ZVL transmission. The anti-phlebotomine capacity of these compounds confirmed in experimental studies makes their use in ZVL control programmes very promising. Limitations and benefits of using this new control tool are compared to current practices. © 2017 The Authors. Tropical Medicine & International Health published by John Wiley & Sons Ltd.

Clinical and electrodiagnostic findings in cyhalothrine poisoning

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Keivan Basiri

2016-01-01

Full Text Available Acute onset bulbar symptoms with respiratory failure and descending paralysis may occur in several neuromuscular disorders including variants of Guillain-Barre syndrome (GBS, diphtheria, botulism and toxins. We present a 51-year-old man who presented with complains of ptosis and dyspnea following pyrethroids spraying in an enclosed area for eradication of flea. Within 5-6 days of admission limb weakness, dysphagia, dysarthria, blurred vision, diplopia, tremor and respiratory distress added to previous symptoms. Temporal profile of events after exposure, development of similar symptoms in patient's son, electrodiagnostic findings and exclusion of other etiologies confirms intoxication etiology. We reviewed the literature and provide an extensive electrodiagnostic overview.

Human bartonellosis: seroepidemiological and clinical features with an emphasis on data from Brazil - A review

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C Lamas

2008-05-01

Full Text Available Bartonellae are fastidious Gram-negative bacteria that are widespread in nature with several animal reservoirs (mainly cats, dogs, and rodents and insect vectors (mainly fleas, sandflies, and human lice. Thirteen species or subspecies of Bartonella have been recognized as agents causing human disease, including B. bacilliformis, B. quintana, B. vinsonii berkhoffii, B. henselae, B. elizabethae, B. grahamii, B. washoensis, B. koehlerae, B. rocha-limaea, and B. tamiae. The clinical spectrum of infection includes lymphadenopathy, fever of unknown origin, endocarditis, neurological and ophthalmological syndromes, Carrion's disease, and others. This review provides updated information on clinical manifestations and seroepidemiological studies with an emphasis on data available from Brazil.

Impact of two specialist insect herbivores on reproduction of horse nettle, Solanum carolinense.

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Wise, Michael J; Sacchi, Christopher F

1996-10-01

The frequency of coevolution as a process of strong mutual interaction between a single plant and herbivore species has been questioned in light of more commonly observed, complex relationships between a plant and a suite of herbivore species. Despite recognition of the possibility of diffuse coevolution, relatively few studies have examined ecological responses of plants to herbivores in complex associations. We studied the impact of two specialist herbivores, the horse nettle beetle, Leptinotarsa juncta, and the eggplant flea beetle, Epitrix fuscula, on reproduction of their host, Solanum carolinense. Our study involved field and controlled-environment experimental tests of the impact on sexual and potential asexual reproduction of attack by individuals of the two herbivore species, individually and in combination. Field tests demonstrated that under normal levels of phytophagous insect attack, horse nettle plants experienced a reduction in fruit production of more than 75% compared with plants from which insects were excluded. In controlled-environment experiments using enclosure-exclosure cages, the horse nettle's two principal herbivores, the flea beetle and the horse nettle beetle, caused decreases in sexual reproduction similar to those observed in the field, and a reduction in potential asexual reproduction, represented by root biomass. Attack by each herbivore reduced the numbers of fruits produced, and root growth, when feeding in isolation. When both species were feeding together, fruit production, but not root growth, was lower than when either beetle species fed alone. Ecological interactions between horse nettle and its two primary herbivores necessary for diffuse coevolution to occur were evident from an overall analysis of the statistical interactions between the two herbivores for combined assessment of fruit and vegetative traits. For either of these traits alone, the interactions necessary to promote diffuse coevolution apparently were lacking.

Molecular detection of Hepatozoon spp. in domestic dogs and wild mammals in southern Pantanal, Brazil with implications in the transmission route.

Science.gov (United States)

de Sousa, Keyla Carstens Marques; Fernandes, Marina Pugnaghi; Herrera, Heitor Miraglia; Benevenute, Jyan Lucas; Santos, Filipe Martins; Rocha, Fabiana Lopes; Barreto, Wanessa Teixeira Gomes; Macedo, Gabriel Carvalho; Campos, João Bosco; Martins, Thiago Fernandes; de Andrade Pinto, Pedro Cordeiro Estrela; Battesti, Darci Barros; Piranda, Eliane Mattos; Cançado, Paulo Henrique Duarte; Machado, Rosangela Zacarias; André, Marcos Rogério

2017-04-15

Hepatozoon parasites comprise intracellular apicomplexan parasites transmitted to vertebrate animals by ingestion of arthropods definitive hosts. The present work aimed to investigate the occurrence of Hepatozoon spp. in wild animals, domestic dogs and their respective ectoparasites, in southern Pantanal region, central-western Brazil, by molecular techniques. Between August 2013 and March 2015, 31 coatis (Nasua nasua), 78 crab-eating foxes (Cerdocyon thous), seven ocelots (Leopardus pardalis), 42 dogs (Canis lupus familiaris), 110 wild rodents (77 Thichomys fosteri, 25 Oecomys mamorae, and 8 Clyomys laticeps), 30 marsupials (14 Thylamys macrurus, 11 Gracilinanus agilis, 4 Monodelphis domestica and 1 Didelphis albiventris), and 1582 ticks and 80 fleas collected from the sampled animals were investigated. DNA samples were submitted to PCR assays for Hepatozoon spp. targeting 18S rRNA gene. Purified amplicons were directly sequenced and submitted to phylogenetic analysis. A high prevalence of Hepatozoon among carnivores (C. thous [91.02%], dogs [45.23%], N. nasua [41.9%] and L. pardalis [71.4%]) was found. However, ticks and fleas were negative to Hepatozoon PCR assays. By phylogenetic analysis based on 18S rRNA sequences, Hepatozoon sequences amplified from crab-eating foxes, dogs, coatis and ocelots clustered with sequences of H. canis, H. americanum and H. felis. The closely related positioning of Hepatozoon sequences amplified from wild rodents and T. macrurus marsupial to Hepatozoon from reptiles and amphibians suggest a possible transmission of those Hepatozoon species between hosts by ectoparasites or by predation. Hepatozoon haplotypes found circulating in wild rodents seem to present a higher degree of polymorphism when compared to those found in other groups of animals. Although rodents seem not to participate as source of Hepatozoon infection to wild carnivores and domestic dogs, they may play an important role in the transmission of Hepatozoon to reptiles

A Molecular Survey for Francisella tularensis and Rickettsia spp. in Haemaphysalis leporispalustris (Acari: Ixodidae) in Northern California.

Science.gov (United States)

Roth, Tara; Lane, Robert S; Foley, Janet

2017-03-01

Francisella tularensis and Rickettsia spp. have been cultured from Haemaphysalis leporispalustris Packard, but their prevalence in this tick has not been determined using modern molecular methods. We collected H. leporispalustris by flagging vegetation and leaf litter and from lagomorphs (Lepus californicus Gray and Sylvilagus bachmani (Waterhouse)) in northern California. Francisella tularensis DNA was not detected in any of 1,030 ticks tested by polymerase chain reaction (PCR), whereas 0.4% of larvae tested in pools, 0 of 117 individual nymphs, and 2.3% of 164 adult ticks were PCR-positive for Rickettsia spp. Positive sites were Laurel Canyon Trail in Tilden Regional Park in Alameda Contra Costa County, with a Rickettsia spp. prevalence of 0.6% in 2009, and Hopland Research and Extension Center in Mendocino County, with a prevalence of 4.2% in 1988. DNA sequencing revealed R. felis, the agent of cat-flea typhus, in two larval pools from shaded California bay and live oak leaf litter in Contra Costa County and one adult tick from a L. californicus in chaparral in Mendocino County. The R. felis in unfed, questing larvae demonstrates that H. leporispalustris can transmit this rickettsia transovarially. Although R. felis is increasingly found in diverse arthropods and geographical regions, prior literature suggests a typical epidemiological cycle involving mesocarnivores and the cat flea, Ctenocephalides felis. To our knowledge, this is the first report of R. felis in H. leporispalustris. Natural infection and transovarial transmission of this pathogen in the tick indicate the existence of a previously undocumented wild-lands transmission cycle that may intersect mesocarnivore-reservoired cycles and collectively affect human health risk. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Myxomatosis in farmland rabbit populations in England and Wales.

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Ross, J; Tittensor, A M; Fox, A P; Sanders, M F

1989-10-01

The overall pattern and consequences of myxomatosis in wild rabbit populations were studied at three farmland sites in lowland southern England and upland central Wales between 1971 and 1978. When results from all years were combined, the disease showed a clear two-peaked annual cycle, with a main autumn peak between August and January, and a subsidiary spring peak during February to April. Rabbit fleas, the main vectors of myxomatosis in Britain, were present on full-grown rabbits in sufficient numbers for transmission to occur throughout the year, but the observed seasonal pattern of the disease appeared to be influenced by seasonal mass movements of these fleas. However other factors were also important including the timing and success of the main rabbit breeding season, the proportion of rabbits which had recovered from the disease and the timing and extent of autumn rabbit mortality from other causes. Significantly more males than females, and more adults and immatures than juveniles, were observed to be infected by myxomatosis. Only 25-27% of the total populations were seen to be infected during outbreaks. Using two independent methods of calculation, it was estimated that between 47 and 69% of infected rabbits died from the disease (much lower than the expected 90-95% for fully susceptible rabbits with the partly attenuated virus strains that predominated). Thus it was estimated that 12-19% of the total rabbit populations were known to have died directly or indirectly from myxomatosis. Although the effects of myxomatosis were much less than during the 1950s and 1960s, it continued to be an important mortality factor. It may still have a regulatory effect on rabbit numbers, with autumn/winter peaks of disease reducing the numbers of rabbits present at the start of the breeding season.

Canine vector-borne diseases in Brazil

Science.gov (United States)

Dantas-Torres, Filipe

2008-01-01

Canine vector-borne diseases (CVBDs) are highly prevalent in Brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. Dogs are affected by many protozoa (e.g., Babesia vogeli, Leishmania infantum, and Trypanosoma cruzi), bacteria (e.g., Anaplasma platys and Ehrlichia canis), and helminths (e.g., Dirofilaria immitis and Dipylidium caninum) that are transmitted by a diverse range of arthropod vectors, including ticks, fleas, lice, triatomines, mosquitoes, tabanids, and phlebotomine sand flies. This article focuses on several aspects (etiology, transmission, distribution, prevalence, risk factors, diagnosis, control, prevention, and public health significance) of CVBDs in Brazil and discusses research gaps to be addressed in future studies. PMID:18691408

Canine vector-borne diseases in Brazil

Directory of Open Access Journals (Sweden)

Dantas-Torres Filipe

2008-08-01

Full Text Available Abstract Canine vector-borne diseases (CVBDs are highly prevalent in Brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. Dogs are affected by many protozoa (e.g., Babesia vogeli, Leishmania infantum, and Trypanosoma cruzi, bacteria (e.g., Anaplasma platys and Ehrlichia canis, and helminths (e.g., Dirofilaria immitis and Dipylidium caninum that are transmitted by a diverse range of arthropod vectors, including ticks, fleas, lice, triatomines, mosquitoes, tabanids, and phlebotomine sand flies. This article focuses on several aspects (etiology, transmission, distribution, prevalence, risk factors, diagnosis, control, prevention, and public health significance of CVBDs in Brazil and discusses research gaps to be addressed in future studies.

Eradication of dracunculiasis from Pakistan.

Science.gov (United States)

Hopkins, D R; Azam, M; Ruiz-Tiben, E; Kappus, K D

1995-09-02

In 1986 the World Health Organization targeted dracunculiasis (Guinea-worm disease), which seriously impairs socioeconomic development in 16 African countries, India, Pakistan, and Yemen, to be eradicated globally. The target date for eradication by the end of 1995 was established in 1991. Pakistan eradicated dracunculiasis from the country in October, 1993, after a national campaign which began in 1987 with a nationwide village-by-village search for cases. The infection, which is transmitted by drinking water from ponds containing infected water fleas, was eradicated by using health education, cloth filters, and the cyclopsicide, temephos; and in the later stages, by case containment. Methods pioneered in Pakistan's National Guinea Worm Eradication Program are now being applied in remaining endemic countries.

Wildlife Plague Surveillance Near the China-Kazakhstan Border: 2012-2015.

Science.gov (United States)

Zhao, S-S; Pulati, Y; Yin, X-P; Li, W; Wang, B-J; Yang, K; Chen, C-F; Wang, Y-Z

2017-12-01

Plague is a zoonotic disease caused by the bacterium Yersinia pestis. This pathogen can be transmitted by fleas and has an enzootic cycle, circulating among small mammals, and occasionally epizootic cycles, infecting other species. In China, infected wild rodents are primarily reservoirs of Y. Pestis and are related to human infection (Int. J. Infect. Dis., 33, 2015 and 67; BMC Microbiol., 9, 2009 and 205). Because shepherd dogs prey on and eat rodents (e.g. marmots and mice), they are valuable sentinel animals for plague serosurveillance in endemic disease foci, although their infections are usually asymptomatic (Vet. Microbiol., 172, 2014 and 339). © 2017 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

Metazoan parasites of dogs in Sabah, Malaysia.

Science.gov (United States)

MacAdam, I; Gudan, D; Timbs, D V; Urquhart, H R; Sewell, M M

1984-02-01

The parasites which occurred most frequently in 175 owned or stray dogs in Sabah were Ancylostoma spp. present in 68% of the animals. Dirofilaria immitis occurred in 70% of the adult dogs but neither D. immitis nor Spirocerca lupi were present in puppies under four months of age. The latter attained a prevalence of 30% in the adults. In contrast Toxocara canis occurred in 81% of the puppies but infrequently in older dogs. Dipylidium caninum was moderately prevalent (15 to 25%) in dogs of all ages. Ticks were the most common arthropod parasite being present on 26% of the dogs and were mainly Rhipicephalus sanguineus. Demodectic and sarcoptic mange were confirmed and fleas and lice were also recovered.

Horizontal transmissible protection against myxomatosis and rabbit hemorrhagic disease by using a recombinant myxoma virus.

Science.gov (United States)

Bárcena, J; Morales, M; Vázquez, B; Boga, J A; Parra, F; Lucientes, J; Pagès-Manté, A; Sánchez-Vizcaíno, J M; Blasco, R; Torres, J M

2000-02-01

We have developed a new strategy for immunization of wild rabbit populations against myxomatosis and rabbit hemorrhagic disease (RHD) that uses recombinant viruses based on a naturally attenuated field strain of myxoma virus (MV). The recombinant viruses expressed the RHDV major capsid protein (VP60) including a linear epitope tag from the transmissible gastroenteritis virus (TGEV) nucleoprotein. Following inoculation, the recombinant viruses induced specific antibody responses against MV, RHDV, and the TGEV tag. Immunization of wild rabbits by the subcutaneous and oral routes conferred protection against virulent RHDV and MV challenges. The recombinant viruses showed a limited horizontal transmission capacity, either by direct contact or in a flea-mediated process, promoting immunization of contact uninoculated animals.

Efficacy of slow-release collar formulations of imidacloprid/flumethrin and deltamethrin and of spot-on formulations of fipronil/(s - methoprene, dinotefuran/pyriproxyfen/permethrin and (s –methoprene/amitraz/fipronil against Rhipicephalus sanguineus and Ctenocephalides felis felis on dogs

Directory of Open Access Journals (Sweden)

Horak Ivan G

2012-04-01

Full Text Available Abstract Background Two studies evaluating the efficacy of an imidacloprid/flumethrin collar (Seresto®, Bayer Animal Health, IVP, a deltamethrin collar (Scalibor®, MSD, CP1, a fipronil/(s-methoprene spot-on (Frontline Combo®, Merial, CP2, a dinotefuran/pyriproxyfen/permethrin spot-on (Vectra 3D®, Ceva, CP3 and an amitraz/fipronil/(s-methoprene spot-on (Certifect®, Merial, CP4/CP5 against repeated infestations with Rhipicephalus sanguineus and Ctenocephalides felis felis on dogs were conducted over periods of 226 days and 71 days respectively. Methods The first study comprised 4 groups of treated dogs and one untreated control group, and the second 3 groups of treated dogs and one control group. Each group consisted of 8 dogs. All dogs were infested with ticks and fleas at regular intervals. Ticks were counted 6 h, 18 h or 48 h after infestations and fleas 24 h after infestations. Efficacies of the treatments were calculated by comparison with the untreated control groups using standard descriptive statistics. Results The protective 48 h tick efficacy was 97.8% to 100% for the IVP (226 days, 69.3% to 97.4% for CP1 (170 days, 99.6% to 43.4% for CP2 (35 days and 98% to 61.4% for CP3 (35 days. The protective 18 h tick efficacy was 98% to 99.6% for the IVP (71 days, 100% to 86.5% for CP4 (29 days, 100% to 72.8% for CP4 after re-treatment (35 days and 98.8% to 54.3% for CP5 (35 days. The protective 6 h tick efficacy was 85.6% at Day 7 and 90.1% to 97.1% from Day 14 onwards for the IVP (70 days, 92.3% to 70.7% for CP4 (35 days, 97.5% to 65.2% for CP4 after re-treatment (35 days and 95.1% to 51.8% for CP5 (35 days. The protective 24 h flea efficacy was 99.5/90.9% to 100% for the IVP (71/226 days, 66.7% to 83% for CP1 (170 days, 100% to 88.5% for CP2 (35 days, 100% to 73.3% for CP3 (35 days, 100% to 98.7% for CP4 (35 days, 100% to 87.5% for CP4 after re-treatment (35 days and 100% to 79.5% for

Best Practices for Preventing Vector-Borne Diseases in Dogs and Humans.

Science.gov (United States)

Dantas-Torres, Filipe; Otranto, Domenico

2016-01-01

Vector-borne diseases constitute a diversified group of illnesses, which are caused by a multitude of pathogens transmitted by arthropod vectors, such as mosquitoes, fleas, ticks, and sand flies. Proper management of these diseases is important from both human and veterinary medicine standpoints, given that many of these pathogens are transmissible to humans and dogs, which often live in close contact. In this review, we summarize the most important vector-borne diseases of dogs and humans and the best practices for their prevention. The control of these diseases would ultimately improve animal and human health and wellbeing, particularly in developing countries in the tropics, where the risk of these diseases is high and access to health care is poor. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ectoparasitic infestation of dogs in Bendel State, Nigeria.

Science.gov (United States)

Ugochukwu, E I; Nnadozie, C C

1985-12-01

An investigation into ectoparasitic infestation of different breeds of dogs presented to four veterinary clinics in Benin, Sapele and Auchi in Bendel State of Nigeria during the period January 1983 to December 1983 is presented. Of a total of 820 dogs examined for ectoparasites 246 (30.00%) were infected by ticks, 226 (27.56%) by lice, 212 (25.85%) by fleas and 109 (13.29%) by mites. The species of ectoparasites identified and their prevalence rates were Rhipicephalus sanguineus (19.5%), Otobius megnini (10.48%), Ctenocephalides canis (25.85%), Demodex canis (13.29%). Common clinical symptoms evinced in this species include scratching, licking, irritation, restlessness, alopecia, otitis externa and dermatitis. Some aspects of epidemiology of canine ectoparasitic infestation are discussed.

Double trouble at high density:

DEFF Research Database (Denmark)

Gergs, André; Palmqvist, Annemette; Preuss, Thomas G

2014-01-01

Population size is often regulated by negative feedback between population density and individual fitness. At high population densities, animals run into double trouble: they might concurrently suffer from overexploitation of resources and also from negative interference among individuals...... regardless of resource availability, referred to as crowding. Animals are able to adapt to resource shortages by exhibiting a repertoire of life history and physiological plasticities. In addition to resource-related plasticity, crowding might lead to reduced fitness, with consequences for individual life...... history. We explored how different mechanisms behind resource-related plasticity and crowding-related fitness act independently or together, using the water flea Daphnia magna as a case study. For testing hypotheses related to mechanisms of plasticity and crowding stress across different biological levels...

North Spain (Burgos wild mammals ectoparasites

Directory of Open Access Journals (Sweden)

Domínguez G.

2004-09-01

Full Text Available Twenty-seven species of arthropods were collected from 105 wild mammals, six wolves Canis lupus (Linnaeus, 1758 included. A total of 87 animals (82,8 % harboured some ectoparasites. Ticks were found in 60 % of the samples, fleas in 51.4 %, chewing-lice in 3.8 %, and others (Mesostigmata and hippoboscids in 3.8 %. Moreover, 42.5 % were single infestation and 57.5 % mixed. Some of the species were new records for a host in spanish country such as Trichodectes canis (De Géer, 1778, Ixodes trianguliceps (Birula, 1895, Ceralophyllus (Monopsyllus S. sciurorum (Schrank, 1803 and Paraceras melis melis (Walker, 1856 on several mammals. Two species were new records for Spain: Chaetopsylla matina (Jordan, 1925 and Archaeopsylla erinacei erinacei (Bouché, 1835.

[Myxomatosis in the sub-antarctic islands of Kerguelen, without vectors, thirty years after its introduction].

Science.gov (United States)

Chapuis, J L; Chantal, J; Bijlenga, G

1994-02-01

Myxoma virus was introduced into the Kerguelen archipelago in 1955-1956. Thirty years after its introduction, the virus is present in most areas inhabited by rabbits. Rabbit fleas and mosquitoes are absent from this group of islands and the disease is transmitted by contact. The timing of the beginning of new myxomatosis outbreaks, the absence of real epizootics as well as the higher percentage of infected males over females are specific observations in favour of this mode of transmission. The majority of 34 isolates tested between 1984 and 1988 are of intermediate virulence (Grades IIIA-IIIB). In these conditions, the impact of myxomatosis virus on rabbit populations estimated on two sites is low. Myxomatosis therefore plays only a minor role in the regulation of rabbit populations.

Le genre Tunga Jarocki, 1838 (Siphonaptera : Tungidae. I – Taxonomie, phylogénie, écologie, rôle pathogène

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Beaucournu J.-C.

2012-11-01

Full Text Available Pour la première fois, les 12 espèces actuellement décrites dans le genre Tunga sont étudiées sur le plan de la taxonomie et de la répartition. Divers aspects de leur biologie et leur rôle pathogène sont également envisagés, et en particulier leur phylogénie, leur chorologie, leur phénologie, leur sexe-ratio et leurs dermecos.

Le genre Tunga Jarocki, 1838 (Siphonaptera : Tungidae). I – Taxonomie, phylogénie, écologie, rôle pathogène

Science.gov (United States)

Beaucournu, J.-C.; Degeilh, B.; Mergey, T.; Muñoz-Leal, S.; González-Acuña, D.

2012-01-01

Pour la première fois, les 12 espèces actuellement décrites dans le genre Tunga sont étudiées sur le plan de la taxonomie et de la répartition. Divers aspects de leur biologie et leur rôle pathogène sont également envisagés, et en particulier leur phylogénie, leur chorologie, leur phénologie, leur sexe-ratio et leurs dermecos. PMID:23193514

Gene up-regulation in response to predator kairomones in the water flea, Daphnia pulex

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Okada Yasukazu

2010-04-01

Full Text Available Abstract Background Numerous cases of predator-induced polyphenisms, in which alternate phenotypes are produced in response to extrinsic stimuli, have been reported in aquatic taxa to date. The genus Daphnia (Branchiopoda, Cladocera provides a model experimental system for the study of the developmental mechanisms and evolutionary processes associated with predator-induced polyphenisms. In D. pulex, juveniles form neckteeth in response to predatory kairomones released by Chaoborus larvae (Insecta, Diptera. Results Previous studies suggest that the timing of the sensitivity to kairomones in D. pulex can generally be divided into the embryonic and postembryonic developmental periods. We therefore examined which of the genes in the embryonic and first-instar juvenile stages exhibit different expression levels in the presence or absence of predator kairomones. Employing a candidate gene approach and identifying differentially-expressed genes revealed that the morphogenetic factors, Hox3, extradenticle and escargot, were up-regulated by kairomones in the postembryonic stage and may potentially be responsible for defense morph formation. In addition, the juvenile hormone pathway genes, JHAMT and Met, and the insulin signaling pathway genes, InR and IRS-1, were up-regulated in the first-instar stage. It is well known that these hormonal pathways are involved in physiological regulation following morphogenesis in many insect species. During the embryonic stage when morphotypes were determined, one of the novel genes identified by differential display was up-regulated, suggesting that this gene may be related to morphotype determination. Biological functions of the up-regulated genes are discussed in the context of defense morph formation. Conclusions It is suggested that, following the reception of kairomone signals, the identified genes are involved in a series of defensive phenotypic alterations and the production of a defensive phenotype.

Characterization of Spotted Fever Group Rickettsiae in Flea and Tick Specimens From Northern Peru

National Research Council Canada - National Science Library

Blair, Patrick J; Jiang, Ju; Schoeler, George B; Moron, Cecilia; Anaya, Elizabeth; Cespedes, Manuel; Cruz, Christopher; Felices, Vidal; Guevara, Carolina; Mendoza, Leonardo; Villaseca, Pablo; Sumner, John W; Richards, Allen L; Olson, James G

2004-01-01

... the focus of an outbreak of febrile disease in humans attributed, in part, to SFG rickettsia infections. Molecular identification of the etiologic agents from these samples was determined after partial sequencing of the 17-kDa common antigen gene...

Structural modifications of bacterial lipopolysaccharide that facilitate Gram-negative bacteria evasion of host innate immunity

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Motohiro eMatsuura

2013-05-01

Full Text Available Bacterial lipopolysaccharide (LPS, a cell wall component characteristic of Gram-negative bacteria, is a representative pathogen-associated molecular pattern that allows mammalian cells to recognize bacterial invasion and trigger innate immune responses. The polysaccharide moiety of LPS primary plays protective roles for bacteria such as prevention from complement attacks or camouflage with common host carbohydrate residues. The lipid moiety, termed lipid A, is recognized by the Toll-like receptor 4 (TLR4/MD-2 complex, which transduces signals for activation of host innate immunity. The basic structure of lipid A is a glucosamine disaccharide substituted by phosphate groups and acyl groups. Lipid A with 6 acyl groups (hexa-acylated form has been indicated to be a strong stimulator of the TLR4/MD-2 complex. This type of lipid A is conserved among a wide variety of Gram-negative bacteria, and those bacteria are easily recognized by host cells for activation of defensive innate immune responses. Modifications of the lipid A structure to less-acylated forms have been observed in some bacterial species, and those forms are poor stimulators of the TLR4/MD-2 complex. Such modifications are thought to facilitate bacterial evasion of host innate immunity, thereby enhancing pathogenicity. This hypothesis is supported by studies of Yersinia pestis LPS, which contains hexa-acylated lipid A when the bacterium grows at 27ºC (the temperature of the vector flea, and shifts to contain less-acylated forms when grown at the human body temperature of 37ºC. This alteration of lipid A forms following transmission of Y. pestis from fleas to humans contributes predominantly to the virulence of this bacterium over other virulence factors. A similar role for less-acylated lipid A forms has been indicated in some other bacterial species, such as Francisella tularensis, Helicobacter pylori, and Porphyromonas gingivalis, and further studies to explore this concept are

CRP-Mediated Carbon Catabolite Regulation of Yersinia pestis Biofilm Formation Is Enhanced by the Carbon Storage Regulator Protein, CsrA.

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Stephan P Willias

Full Text Available The natural transmission of Yersinia pestis is reliant upon biofilm blockage of the flea vector. However, the environmentally-responsive adaptive regulators which facilitate Y. pestis biofilm production in accordance with the flea midgut milieu are not well understood. We seek to establish the impact of available carbon source metabolism and storage upon Y. pestis biofilm production. Our findings demonstrate that Y. pestis biofilm production is subject to carbon catabolite regulation in which the presence of glucose impairs biofilm production; whereas, the sole metabolism of alternate carbon sources promotes robust biofilm formation. This observation is facilitated by the cAMP receptor protein, CRP. In accordance with a stark growth defect, deletion of crp in both CO92 and KIM6+ Y. pestis strains significantly impaired biofilm production when solely utilizing alternate carbon sources. Media supplementation with cAMP, a small-molecule activator of CRP, did not significantly alter Y. pestis biofilm production. Furthermore, CRP did not alter mRNA abundance of previously-characterized hms biofilm synthesis and regulation factors. Therefore, our findings indicate CRP does not confer a direct stimulatory effect, but may indirectly promote Y. pestis biofilm production by facilitating the alternate carbon source expression profile. Additionally, we assessed the impact of the carbon storage regulator protein, CsrA, upon Y. pestis biofilm production. Contrary to what has been described for E. coli, Y. pestis biofilm formation was found to be enhanced by CsrA. Regardless of media composition and available carbon source, deletion of csrA significantly impaired Y. pestis biofilm production. CsrA was found to promote Y. pestis biofilm production independent of glycogen regulation. Loss of csrA did not significantly alter relative hmsH, hmsP, or hmsT mRNA abundance. However, deletion of hmsP in the csrA-deficient mutant enabled excessive biofilm production

Factors affecting patterns of Amblyomma triste (Acari: Ixodidae) parasitism in a rodent host.

Science.gov (United States)

Colombo, Valeria C; Nava, Santiago; Antoniazzi, Leandro R; Monje, Lucas D; Racca, Andrea L; Guglielmone, Alberto A; Beldomenico, Pablo M

2015-07-30

Here we offer a multivariable analysis that explores associations of different factors (i.e., environmental, host parameters, presence of other ectoparasites) with the interaction of Amblyomma triste immature stages and one of its main hosts in Argentina, the rodent Akodon azarae. Monthly and for two years, we captured and sampled rodents at 16 points located at 4 different sites in the Parana River Delta region. The analyses were conducted with Generalized Linear Mixed Models with a negative binomial response (counts of larvae or nymphs). The independent variables assessed were: (a) environmental: trapping year, season, presence of cattle; type of vegetation (natural grassland or implanted forest); rodent abundance; (b) host parameters: body length; sex; body condition; blood cell counts; natural antibody titres; and (c) co-infestation with other ectoparasites: other stage of A. triste; Ixodes loricatus; lice; mites; and fleas. Two-way interaction terms deemed a priori as relevant were also included in the analysis. Larvae were affected by all environmental variables assessed and by the presence of other ectoparasites (lice, fleas and other tick species). Host factors significantly associated with larval count were sex and levels of natural antibodies. Nymphs were associated with season, presence of cattle, body condition, body length and with burdens of I. loricatus. In most cases, the direction and magnitude of the associations were context-dependent (many interaction terms were significant). The findings of greater significance and implications of our study are two. Firstly, as burdens of A. triste larvae and nymphs were greater where cattle were present, and larval tick burdens were higher in implanted forests, silvopastoral practices developing in the region may affect the population dynamics of A. triste, and consequently the eco-epidemiology of Rickettsia parkeri. Secondly, strong associations and numerous interactions with other ectoparasites suggest that

Ectoparasites of dogs and cats in Albania.

Science.gov (United States)

Xhaxhiu, Dashamir; Kusi, Ilir; Rapti, Dhimiter; Visser, Martin; Knaus, Martin; Lindner, Thomas; Rehbein, Steffen

2009-11-01

One hundred eighty-one dogs and 26 short-hair cats from suburban areas around Tirana, Albania were examined for ectoparasite infestation. The dogs were examined on several occasions from 2005 through 2009 representing three seasons: winter (December-February), spring (March-May), and summer (June-August); the cats were examined in late autumn (November). In addition, deep ear swab specimens of 30 dogs were examined for ear mites. The arthropod ectoparasite fauna of the dogs included two tick species (Rhipicephalus sanguineus and Ixodes ricinus), three mite species (Sarcoptes scabiei var. canis, Otodectes cynotis, and Demodex canis), three flea species (Ctenocephalides canis, Ctenocephalides felis, and Pulex irritans), and one louse species (Trichodectes canis). In the dogs, rates of infestation were 23.8% for R. sanguineus, 0.6% for I. ricinus, 4.4% for S. scabiei var. canis, 6.7% for O. cynotis, 0.6% for D. canis, 75.7% for C. canis, 5.0% for C. felis, 8.3% for P. irritans, and 6.6% for T. canis. Mixed infestation with two or three species of ectoparasites was recorded on 38.1% of the dogs. Fleas infested 75.7% dogs (geometric mean, 3.96; range, 1-80) and were observed in winter, spring, and summer with increasing prevalences of 64.3%, 75.9%, and 100%. Ticks parasitized 24.3% of the dogs (geometric mean, 0.41; range, 1-331). R. sanguineus ticks were recorded on 34.2% and 50% of the dogs examined in spring and summer, respectively, but were absent on the dogs during winter except for a single I. ricinus specimen observed. Prevalence of infestation with R. sanguineus, S. scabiei var. canis, C. felis, P. irritans, and T. canis did not differ between dogs 6 months of age; however, prevalence of infestation with C. canis was significantly (p 6 months old. There was no difference between the sexes for the prevalences of infestation with those parasites. The examination of the cats revealed infestation with only one species of ectoparasite, C. felis (prevalence, 100

Human exposure to selamectin from dogs treated with revolution: methodological consideration for selamectin isolation.

Science.gov (United States)

Gupta, R C; Masthay, M B; Canerdy, T D; Acosta, T M; Provost, R J; Britton, D M; Atieh, B H; Keller, R J

2005-01-01

This study was undertaken to determine selamectin residue in dog's blood and in gloves worn while petting dogs after Revolution application. Revolution contains the active ingredient selamectin (a semisynthetic avermectin), which controls endoparasites and ectoparasites, including adult fleas, flea eggs, ticks, heartworms, ear mites, and sarcoptic mange in dogs, for 30 days. Revolution was applied topically on a group of six adult house hold dogs (240 mg selamectin/dog). The gloves worn for 5 min while petting the dogs were collected in glass jars and the blood samples (5 mL/dog) were collected in EDTA tubes at 0 h, 24 h, and 72 h, and at 1, 2, 3, 4, and 5 weeks post-Revolution application for selamectin residue determination. At no time during the study did the dogs show any signs of toxicity, weight loss, or change in body temperature. Extracts of the blood and the gloves were analyzed for selamectin residue using RP-HPLC coupled with a UV detector (246 nm). Selamectin standard used for peak identification and quantitation was purified from Revolution. Selamectin residue was detected in the blood (10.26 +/- 1.06 ng/mL) only at 72 h post-Revolution application, probably due to its poor dermal absorption and rapid elimination from the circulation. In the glove extracts, the highest concentration of selamectin (518.90 +/- 66.80 ppm) was detected 24 h after Revolution application. Transferable residue of selamectin in gloves from dog's coat was detected at a lesser magnitude after 1 week of Revolution application, and that was followed by a further descending trend during the second, third, and fourth weeks. No selamectin residue was detected in the glove extracts after the fifth week. In spite of selamectin's binding to the sebaceous glands of the skin, gloves contained significant transferable residue. Thus, these findings suggest that repeated exposure to selamectin can pose potential health risks, especially to veterinarians, veterinary technologists, dog

Study on the uptake and distribution of gadolinium based contrast agents in biological samples using laser ablation with inductively coupled plasma mass spectroscopy; Untersuchungen zur Aufnahme und Verteilung von gadoliniumbasierten Kontrastmitteln in biologischen Proben mittels Laserablation mit induktiv gekoppelter Plasma-Massenspektrometrie

Energy Technology Data Exchange (ETDEWEB)

Lingott, Jana

2016-01-05

Gadolinium based contrast agents are used for magnetic resonance imaging. After their excretion by medicated patients they reach surface water passing waste water treatment plants where they are not removed sufficiently. The behavior of the contrast agents in the environment and the interaction with organisms was investigated in this work due to the toxicity of the free Gd{sup 3+} ion and the associated risks, such as accumulation in the human food chain. In this work, the two elemental analytical imaging methods laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and synchrotron radiation X-ray fluorescence analysis (SRXRF) have been used to investigate the uptake, distribution, and excretion of Gd-based contrast agents by various biological systems. Both methods were analytically characterized and compared for this application. The detection limits of gadolinium were determined under optimized conditions by LA-ICP-MS and SRXRF. With calibration by remains of dried elemental standard droplets detection limits of 0.78 pg absolute amount of gadolinium (LA-ICP-MS), respectively 89 pg (SRXRF) were reached. Based on filamentous algae as water plants the uptake and the excretion of Gd-based contrast agents were revealed. The dependence on concentration of the contrast agent in the exposition solution and the independence of temporal uptake within one to seven days were studied for duckweed. By LA-ICP-MS gadolinium was quantified in a leaf of cress plant. The verification of the results was performed by SRXRF and ICP-MS after digestion. Furthermore, the uptake and distribution of Gd-based contrast agents in higher organisms (water flea) were observed. The exact location of gadolinium was resolved by three-dimensional μ-computed tomography by the comparison of an exposed with a Gd-free water flea. In all studies, gadolinium was detected in the investigated exposed model organisms. It can be concluded that the contrast agents were taken from the

O virus do mixoma no coelho do mato (Sylvilagus minenses, sua transmissão pelos Aedes scapularis e aegypti

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Henrique Beaurepaire Aragão

1943-01-01

Full Text Available The brazilian wild rabbit (Sylvilagus minensis is sensible to the virus of the mixomatosis but the desease takes on it a mild character, lasts for long time and generally do not kill the animal. The tumors are generally smaller and less numerous than those of the domestic rabbit, but sometimes there were noted large and flat lesions (fig. 3. The natural infection of the wild rabbit may be quite common not only because many rabbits caught in the country were found to be immune as also because it was found among the animals caught in the country near Rio, one that was infected with mixomatosis. The experimental infection of the Sylvilagus may be easily obtained by cutan, subcutan or conjuntival way and also when a health wild rabbit is placed in the same cage with a sick domestic animal. It is also possible to obtain the infection of the wild and domestic rabbits by the bite of infected blood sucking insects as fleas and mosquitoes. The infected mosquito can transmit the disease 2 or 3 times til 17 days after an infective meal on a sick rabbit. The transmission is a mecanical one and only the proboscis of the insect contains the virus as it was shown by the inoculation of emulsions of the proboscis, thorax and abdomen of the mosquito. Though mecanical this kind of transmission acts as an important epidemiological mean of dissemination of the deseasse and splains the suddendly outbreaks of mixomatosis in rabbits breedings where no new rabbits were introduced since very long time. The transmition of mixomatosis by fleas (Slenopsylla was at first demonstrated by us, then S. Torres pointed out the capacity of Culex fatigans to transmit the desease and now we have proved that Aedes scapularis and Aedes aegypti were also able to transmit it (Foto 1 and 2. The virus of the mixomatosis (Chlamidozoon mixoma is seen on the smeavs of the tumors of the wild reabbit with the same morphology, as in the material of the domestic animal.

Hypoxylon pulicicidum sp. nov. (Ascomycota, Xylariales, a pantropical insecticide-producing endophyte.

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Gerald F Bills

Full Text Available BACKGROUND: Nodulisporic acids (NAs are indole diterpene fungal metabolites exhibiting potent systemic efficacy against blood-feeding arthropods, e.g., bedbugs, fleas and ticks, via binding to arthropod specific glutamate-gated chloride channels. Intensive medicinal chemistry efforts employing a nodulisporic acid A template have led to the development of N-tert-butyl nodulisporamide as a product candidate for a once monthly treatment of fleas and ticks on companion animals. The source of the NAs is a monophyletic lineage of asexual endophytic fungal strains that is widely distributed in the tropics, tentatively identified as a Nodulisporium species and hypothesized to be the asexual state of a Hypoxylon species. METHODS AND RESULTS: Inferences from GenBank sequences indicated that multiple researchers have encountered similar Nodulisporium endophytes in tropical plants and in air samples. Ascomata-derived cultures from a wood-inhabiting fungus, from Martinique and closely resembling Hypoxylon investiens, belonged to the same monophyletic clade as the NAs-producing endophytes. The hypothesis that the Martinique Hypoxylon collections were the sexual state of the NAs-producing endophytes was tested by mass spectrometric analysis of NAs, multi-gene phylogenetic analysis, and phenotypic comparisons of the conidial states. We established that the Martinique Hypoxylon strains produced an ample spectrum of NAs and were conspecific with the pantropical Nodulisporium endophytes, yet were distinct from H. investiens. A new species, H. pulicicidum, is proposed to accommodate this widespread organism. CONCLUSIONS AND SIGNIFICANCE: Knowledge of the life cycle of H. pulicicidum will facilitate an understanding of the role of insecticidal compounds produced by the fungus, the significance of its infections in living plants and how it colonizes dead wood. The case of H. pulicicidum exemplifies how life cycle studies can consolidate disparate observations of a

Change in phenotypic plasticity of a morphological defence in Daphnia galeata (Crustacea: Cladocera in a selection experiment

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Koichi FUJII

2007-08-01

Full Text Available Some water fleas Daphnia change their head morphology to reduce predation risk in response to chemical substances (kairomones released from larvae of the invertebrate predator Chaoborus (Insecta: Diptera. We tested for evidence of the costs associated with elongation of the head spine in Daphnia galeata and the consequences of these costs on the inducibility of head spine elongation in predictable and unpredictable environments. We exposed D. galeata in outdoor experimental ponds to conditions under which predation pressure by Chaoborus larvae and the concentration of kairomones from this predator were controlled for about 70 days. In the laboratory, we then used Daphnia clones collected from the outdoor ponds to investigate the inducibility of head spine formation in response to Chaoborus kairomones. The inducibility of head spine formation increased in D. galeata from the ponds that had contained both predators and kairomones, whereas in water fleas from the ponds containing only kairomones the plasticity (inducibility of head spine formation decreased compared with that in the control ponds. These results suggest that the production of a defensive head spine, its phenotypic plasticity, or both entail some costs. Contrary to our predictions, exposure to Chaoborus kairomones in the laboratory resulted in head lengths that were not significantly different among any of the clones from the three outdoor treatments. We found no evidence for costs associated with head spine elongation in terms of fecundity, time to maturity, or intrinsic rate of natural population increase. Average within-clone partial correlations calculated for head length and intrinsic rate of natural population increase, corrected for body length, were not significantly negative, indicating no cost of defence. This was probably because food conditions in the laboratory were so good that the costs of defence could not be detected. Furthermore, community-level changes, such as

Study on the uptake and distribution of gadolinium based contrast agents in biological samples using laser ablation with inductively coupled plasma mass spectroscopy

International Nuclear Information System (INIS)

Lingott, Jana

2016-01-01

Gadolinium based contrast agents are used for magnetic resonance imaging. After their excretion by medicated patients they reach surface water passing waste water treatment plants where they are not removed sufficiently. The behavior of the contrast agents in the environment and the interaction with organisms was investigated in this work due to the toxicity of the free Gd 3+ ion and the associated risks, such as accumulation in the human food chain. In this work, the two elemental analytical imaging methods laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and synchrotron radiation X-ray fluorescence analysis (SRXRF) have been used to investigate the uptake, distribution, and excretion of Gd-based contrast agents by various biological systems. Both methods were analytically characterized and compared for this application. The detection limits of gadolinium were determined under optimized conditions by LA-ICP-MS and SRXRF. With calibration by remains of dried elemental standard droplets detection limits of 0.78 pg absolute amount of gadolinium (LA-ICP-MS), respectively 89 pg (SRXRF) were reached. Based on filamentous algae as water plants the uptake and the excretion of Gd-based contrast agents were revealed. The dependence on concentration of the contrast agent in the exposition solution and the independence of temporal uptake within one to seven days were studied for duckweed. By LA-ICP-MS gadolinium was quantified in a leaf of cress plant. The verification of the results was performed by SRXRF and ICP-MS after digestion. Furthermore, the uptake and distribution of Gd-based contrast agents in higher organisms (water flea) were observed. The exact location of gadolinium was resolved by three-dimensional μ-computed tomography by the comparison of an exposed with a Gd-free water flea. In all studies, gadolinium was detected in the investigated exposed model organisms. It can be concluded that the contrast agents were taken from the environment.

Multispacer typing of Rickettsia isolates from humans and ticks in Tunisia revealing new genotypes.

Science.gov (United States)

Znazen, Abir; Khrouf, Fatma; Elleuch, Nihel; Lahiani, Dorra; Marrekchi, Chakib; M'Ghirbi, Youmna; Ben Jemaa, Mounir; Bouattour, Ali; Hammami, Adnene

2013-12-31

Rickettsioses are important remerging vector born infections. In Tunisia, many species have been described in humans and vectors. Genotyping is important for tracking pathogen movement between hosts and vectors. In this study, we characterized Rickettsia species detected in patients and vectors using multispacer typing (MST), proposed by Founier et al. and based on three intergenic spacers (dksA-xerC, rmpE- tRNA(fMet), mppA-pruC) sequencing. Our study included 25 patients hospitalized during 2009. Ticks and fleas were collected in the vicinity of confirmed cases. Serology was performed on serum samples by microimmunofluorescence using Rickettsia conorii and Rickettsia typhi antigens. To detect and identify Rickettsia species, PCR targeting ompA, ompB and gltA genes followed by sequencing was performed on 18 obtained skin biopsies and on all collected vectors. Rickettsia positive samples were further characterized using primers targeting three intergenic spacers (dksA-xerC, rmpE- tRNA(fMet) and mppA-purC). A rickettsial infection was confirmed in 15 cases (60%). Serology was positive in 13 cases (52%). PCR detected Rickettsia DNA in four biopsies (16%) allowing the identification of R. conorii subsp israelensis in three cases and R. conorii subsp conorii in one case. Among 380 collected ticks, nine presented positive PCR (2.4%) allowing the identification of six R. conorii subsp israelensis, two R. massiliae and one R. conorii subsp conorii. Among 322 collected fleas, only one was positive for R. felis. R. conorii subsp israelensis strains detected in humans and vectors clustered together and showed a new MST genotype. Similarly, R. conorii subsp conorii strains detected in a skin biopsy and a tick were genetically related and presented a new MST genotype. New Rickettsia spotted fever strain genotypes were found in Tunisia. Isolates detected in humans and vectors were genetically homogenous despite location differences in their original isolation suggesting

Zoonoses from pets horses, donkeys and mules: with special references to Egypt.

Science.gov (United States)

Morsy, Ayman T A; Saleh, Mostafa S M; Morsy, Tosson A

2014-04-01

A zoonosis is an animal disease that is transmissible to humans. Humans are usually an accidental host that acquires disease through close contact with an infected animal, who may or may not be symptomatic. Children are at highest risk for infection because they are more likely to have close contact with pets. Pets are responsible for transmission of an extensive array of bacterial, fungal, and parasitic zoonotic pathogens. The route of transmission can be through the saliva (e.g., bites or contaminated scratches), feces, respiratory secretions, direct contact, or by the animal acting as a vehicle and source of tick or flea exposure. Although pets have been implicated in transmission of zoonoses to their owners, risk of transmission from contact with pets is low and may be further reduced by simple precautions.

Cytopathology of parasitic dermatitis in dogs.

Science.gov (United States)

Sood, N K; Mekkib, Berhanu; Singla, L D; Gupta, K

2012-04-01

Out of 44 cases of dermatitis in dogs, 11 cases of parasitic origin were analyzed by cytopathology. Histopathologic examination of punch biopsies was also done for correlation with cytologic findings. Sarcoptic dermatitis was recorded in six cases, wherein, besides sarcoptic mites, neutrophils, macrophages, and plasma cells and keratinizing epithelial cells were also seen. Hematology revealed a relative neutrophilia and mild eosinophilia. Four cases of severe and generalized demodicosis complicated with bacteria and/or Malassezia sp. infection were also recorded. Histopathologically numerous Demodex sp. mites in varying stage of maturation were found damaging the hair follicles along with associated pathological changes and foreign body granulomas in one case. In addition, flea allergy dermatitis was also observed in one dog. In nutshell, cytology was found to be unequivocally effective in diagnosing parasitic dermatitis.

A molecular epidemiological survey of Babesia, Hepatozoon, Ehrlichia and Anaplasma infections of dogs in Japan

Science.gov (United States)

KUBO, Shotaro; TATENO, Morihiro; ICHIKAWA, Yasuaki; ENDO, Yasuyuki

2015-01-01

Tick-borne diseases are often encountered in canine clinical practice. In the present study, a molecular epidemiological survey of dogs in Japan was conducted to understand the prevalence and geographical distribution of Babesia spp., Hepatozoon spp., Ehrlichia spp. and Anaplasma spp. Pathogen-derived DNA in blood samples obtained from 722 dogs with a history of exposure to ticks and/or fleas was examined by PCR. The prevalence of Babesia gibsoni, Babesia odocoilei-like species, Hepatozoon canis and Ehrlichia spp./Anaplasma spp. was 2.4% (16/722), 0.1% (1/722), 2.5% (18/722) and 1.5% (11/722), respectively. While B. gibsoni and Ehrlichia spp./Anaplasma spp. were detected in the western part of Japan, H. canis was detected in Tohoku area in addition to western and central parts of Japan. PMID:25947226

U.S. EPA, Pesticide Product Label, X-O-TROL FLEA & TICK FOGGER, 09/13/1990

Science.gov (United States)

2011-04-21

. ' ~. r L NOT · ~. - D fta.'.TIlltATIO" . o ftllfltIlGIIT .. ATIOH' (Under lhe Foderlll Insecticide. FunRicide. ... 00 ••• • • 00 • o 00 .0' •••• MAR. gn ·1990 • • • • ...

Antifreeze Production and Cold-Tolerance in Overwintering Purple Martin Fleas, Ceratophyllus idius Jordan and Rothschild.

Science.gov (United States)

1986-08-01

1980. The origin of free glycerol accumulated in diapause eggs of Bombyx mori . Physiol. Entomol. 5: 93-97. Zachariassen, K.E. 1977. Effects of... Bombyx mori , isotope [ 14C] studies showed that about 1/3 of the free glycerol pool came from lipids (Yaginuma and Yamashita 1980). However, the same... Bombyx silkworm. Nature, Lond. 180: 606-607. Chino, H. 1958. Carbohydrate metabolism in the diapause egg of the silkworm, Bombyx mori -II. Conversion of

Biological Aspects for Forecasting of the Cabbage Stem Flea Beetle, Psylliodes chrysocephala L

DEFF Research Database (Denmark)

Mathiasen, Helle

a mostly minor damage by feeding on the leaves of young plants. The main damage is caused by the larvae mining the petioles and later stems from the autumn to following spring. Forecasting is widely based on monitoring the activity density of the adult beetles with yellow water traps in the main period...... and - 10˚C and the influence of cold acclimation and larval stage tested. As part of the project, an assessment of the initial plant injury was carried out and evaluated as an alternative monitoring method to estimate CSFB abundance in the field. This was tested in a field cage experiment with densities...... of 1, 2, 4 and 8 pairs of beetles at a plant density of 24. The assessment of the initial plant injury showed a low level of infestation in terms of both plant injury and larval density per plant, and this monitoring not to be reliable indicator of beetle density. There was not a significant...

Titanium dioxide nanoparticles increase sensitivity in the next generation of the water flea Daphnia magna.

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Mirco Bundschuh

Full Text Available The nanoparticle industry is expected to become a trillion dollar business in the near future. Therefore, the unintentional introduction of nanoparticles into the environment is increasingly likely. However, currently applied risk-assessment practices require further adaptation to accommodate the intrinsic nature of engineered nanoparticles. Combining a chronic flow-through exposure system with subsequent acute toxicity tests for the standard test organism Daphnia magna, we found that juvenile offspring of adults that were previously exposed to titanium dioxide nanoparticles exhibit a significantly increased sensitivity to titanium dioxide nanoparticles compared with the offspring of unexposed adults, as displayed by lower 96 h-EC(50 values. This observation is particularly remarkable because adults exhibited no differences among treatments in terms of typically assessed endpoints, such as sensitivity, number of offspring, or energy reserves. Hence, the present study suggests that ecotoxicological research requires further development to include the assessment of the environmental risks of nanoparticles for the next and hence not directly exposed generation, which is currently not included in standard test protocols.

Quantifying sublethal effects of glyphosate and Roundup® to Daphnia magna using a fluorescence based enzyme activity assay and video tracking

DEFF Research Database (Denmark)

Roslev, Peter; R. Hansen, Lone; Ørsted, Michael

Glyphosate (N-(phosphonomethyl)glycine) is the active ingredient in a range of popular broad-spectrum, non-selective herbicide formulations. The toxicity of this herbicide to non-target aquatic organisms such as Daphnia magna is often evaluated using conventional toxicity assays that focus...... on endpoints such as immobility and mortality. In this study, we investigated sublethal effects of glyphosate and Roundup® to D. magna using video tracking for quantifying behavioral changes, and a novel fluorescence based assay for measuring in vivo hydrolytic enzyme activity (FLEA assay). Roundup® exposure...... resulted in concentration-dependent inhibition of alkaline phosphatase activity in D. magna. The inhibition of alkaline phosphatase by Roundup® was temperature-dependent with lowest inhibition at 14 °C and greater inhibition at 20 and 26 °C. Exposure of D. magna to sublethal concentrations of glyphosate...

Zoonoses from dogs with special reference to Egypt.

Science.gov (United States)

Sabry, Abdel-Hameed A; Morsy, Ayman T A; Morsy, Tosson A

2012-12-01

A zoonosis is an animal disease that is transmissible to humans. Humans are usually an accidental host that acquires disease through close contact with an infected animal, who may or may not be symptomatic. Children are at highest risk for infection because they are more likely to have close contact with pets. Dogs are responsible for transmission of an extensive array of bacterial and parasitic zoonotic pathogens. The route of transmission can be through the feces, urine, saliva (eg, bites or contaminated scratches), or respiratory secretions of the animal, or by the dog or cat acting as a vehicle and source of tick or flea exposure or reservoir for vector borne disease. Although dogs have been implicated in transmission of zoonoses to their owners, risk of transmission from contact with dogs is low and may be further reduced by simple precautions.

FAUNA BINATANG MENGERAT DAN PARASITNYA DI BEBERAPA DAERAH TRANSMIGRASI DI INDONESIA, SERTA HUBUNGANNYA DENGAN PENYAKIT RICKETTSIOSIS YANG DITULARKAN OLEH VEKTOR

Directory of Open Access Journals (Sweden)

Tuti R. Hadi

2012-09-01

Full Text Available Surveys on small mammal parasites conducted in several transmigration schemes in South Sulawesi, Central Sulawesi and East Kalimantan, Indonesia revealed 10 species of murid rodents. Rattus exulans and some forest rats were predominant in newly opened schemes, whereas Rattus rattus was predomi­nant in older schemes. Six species of rats collected in all areas surveyed were found infested with a chigger species Lepto trombodium (L. deliensis, a known vector of scrub typhus. Xenopsylla cheopis, a flea vector of murine typhus, was not found during the survey. Serological studies revealed that 22.7% of the rats collected in an area planned for a transmigration scheme in Central Sulawesi, have antibodies against scrub typhus and 12,5% against murine typhus. The risk of transmission of scrub typhus and murine typhus to human is discussed.

Residential Waste

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Fruergaard, Thilde; Matsufuji, Y.

2011-01-01

are discussed in this chapter. Characterizing residential waste is faced with the problem that many residences already divert some waste away from the official collection systems, for example performing home composting of vegetable waste and garden waste, having their bundled newspaper picked up by the scouts...... twice a year or bringing their used furniture to the flea markets organized by charity clubs. Thus, much of the data available on residential waste represents collected waste and not necessarily all generated waste. The latter can only be characterized by careful studies directly at the source......, but such studies are very expensive if fair representation of both spatial and temporal variations should be obtained. In addition, onsite studies may affect the waste generation in the residence because of the increased focus on the issue. Residential waste is defined in different ways in different countries...

[Plague outbreaks in the Mediterranean area during the 2nd World War, epidemiology and treatments].

Science.gov (United States)

Mafart, B; Brisou, P; Bertherat, E

2004-11-01

Before the Second World War, the plague was still rife in North Africa but occurred only as sporadic cases or small outbreaks as in Egypt or Morocco. The permanent foci of infected wild rodent were the cause of these rural outbreaks. In 1943 and 1944, plague came back in several Mediterranean towns and ports and was considered as a serious danger for the Allied Forces. These resurgences were related to the World War as well as the overpopulation of the cities, regroupings and population movements, relaxation of prophylactic measures of the plague in sea transport. The Allied Forces medical officers then showed the resistance of Yersinia pestis to penicillin which they had been supplied with recently, the effectiveness of sulphamides but mortality remained high (27%). In parallel, the drastic fight against rodents and fleas (DDT) gave excellent results.

Assessment of Climate Change and Vector-borne Diseases in the United States

Science.gov (United States)

Monaghan, A. J.; Beard, C. B.; Eisen, R. J.; Barker, C. M.; Garofalo, J.; Hahn, M.; Hayden, M.; Ogden, N.; Schramm, P.

2016-12-01

Vector-borne diseases are illnesses that are transmitted by vectors, which include mosquitoes, ticks, and fleas. The seasonality, distribution, and prevalence of vector-borne diseases are influenced significantly by climate factors, primarily high and low temperature extremes and precipitation patterns. In this presentation we summarize key findings from Chapter 5 ("Vector-borne Diseases") of the recently published USGCRP Scientific Assessment of the Impacts of Climate Change on Human Health in the United States. Climate change is expected to alter geographic and seasonal distributions of vectors and vector-borne diseases, leading to earlier activity and northward range expansion of ticks capable of carrying the bacteria that cause Lyme disease and other pathogens, and influencing the distribution, abundance and prevalence of infection in mosquitoes that transmit West Nile virus and other pathogens. The emergence or reemergence of vector-borne pathogens is also likely.

Sylvatic plague vaccine and management of prairie dogs

Science.gov (United States)

Rocke, Tonie E.

2012-01-01

Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at the University of Wisconsin (UW), have developed a sylvatic plague vaccine that shows great promise in protecting prairie dogs against plague (Mencher and others, 2004; Rocke and others, 2010). Four species of prairie dogs reside in the United States and Canada, and all are highly susceptible to plague and regularly experience outbreaks with devastating losses. Along with habitat loss and poisoning, plague has contributed to a significant historical decline in prairie dog populations. By some estimates, prairie dogs now occupy only 1 to 2 percent of their former range (Proctor and others, 2006), with prairie dog colonies being now much smaller and fragmented than they were historically, making individual colonies more vulnerable to elimination by plague (Antolin and others, 2002). At least one species, the Utah prairie dog (Cynomys parvidens) is listed by the U.S. Fish and Wildlife Service (FWS) as "threatened." Controlling plague is a vital concern for ongoing management and conservation efforts for prairie dogs. Current efforts to halt the spread of plague in prairie dog colonies typically rely on dusting individual prairie dog burrows with pesticides to kill plague-infected fleas. Although flea-control insecticides, such as deltamethrin, are useful in stopping plague outbreaks in these prairie dog colonies, dusting of burrows is labor intensive and time consuming and may affect other insects and arthropods. As an alternative approach, NWHC and UW scientists developed a sylvatic plague vaccine (SPV) for prairie dogs that can be delivered via oral bait. Laboratory studies have shown that consumption of this vaccine-laden bait by different prairie dog species results in significant protection against plague infection that can last for at least 9 months (Rocke and others, 2010; Rocke, unpublished). Work has now shifted to optimizing baits and distribution methods for

Animal and human tungiasis-related knowledge and treatment practices among animal keeping households in Bugiri District, South-Eastern Uganda.

Science.gov (United States)

Mutebi, Francis; Krücken, Jürgen; von Samson-Himmelstjerna, Georg; Waiswa, Charles; Mencke, Norbert; Eneku, Wilfred; Andrew, Tamale; Feldmeier, Hermann

2018-01-01

Zoonotic tungiasis caused by Tunga penetrans remains a serious public and animal health problem among endemic villages in Uganda and many sub Saharan African countries. Studies on human and animal tungiasis-related knowledge and treatment practices in endemic communities have never been undertaken, a limitation to development of sustainable control measures. A cross sectional study using semi-structured questionnaires (Supplementary file S1) was conducted among 236 animal rearing households in 10 endemic villages in Bugiri District, South-Eastern Uganda. Focus group discussions and observation checklists were used to validate and clarify the findings. Most respondents knew the aetiology (89.4%), clinical signs (98%) and the ecology of T. penetrans as well as the major risk factors of human tungiasis (65.2%). In contrast, very few respondents were aware of animal tungiasis. Only 4.8% of those with infected animals on the compound knew that some of their animals were infected and 13.6% of the respondents had ever seen tungiasis-affected animals. Pigs (13.1%, n=31) and dogs (0.85%, n=2) were the only T. penetrans animal hosts known to animal owners. Affected humans were treated by extraction of embedded sand fleas using non-sterile sharp instruments in all households that reported occurrence of human tungiasis at least once (n=227). Also, affected animals were mainly treated by mechanical removal of embedded sand fleas in households that have ever experienced animal tungiasis (four out of 12; 33.3%). In a few instances, plant and animal pesticides (n=3) and other chemicals such as grease, paraffin and wood preservative (n=3) were also used to treat animal tungiasis. The study revealed a high level of knowledge on human tungiasis but inadequate knowledge on the zoonotic nature of tungiasis. Commonly applied methods for treatment of human and animal tungiasis are a health hazard by themselves. Concerted i.e. One Health-based efforts aiming at promoting appropriate

[Origin of the plague microbe Yersinia pestis: structure of the process of speciation].

Science.gov (United States)

Suntsov, V V

2012-01-01

The origin and evolution of the plague microbe Yersinia pestis are considered in the context of propositions of modern Darwinism. It was shown that the plague pathogen diverged from the pseudotuberculous microbe Yersinia pseudotuberculosis O:1b in the mountain steppe landscapes of Central Asia in the Sartan: 22000-15000 years ago. Speciation occurred in the tarbagan (Marmota sibirica)--flea (Oropsylla silantiewi) parasitic system. The structure of the speciation process included six stages: isolation, genetic drift, enhancement of intrapopulational polymorphism, the beginning of pesticin synthesis (genetic conflict and emergence of hiatus), specialization (stabilization of characteristics), and adaptive irradiation (transformation of the monotypic species Y. pestis tarbagani into a polytypic species). The scenario opens up wide prospects for construction of the molecular phylogeny of the plague microbe Y. pestis and for investigation of the biochemical and molecular-genetic aspects of "Darwinian" evolution of pathogens from many other nature-focal infections.

[A NATURAL PLAGUE FOCUS. IN GORNYI ALTAI: FORMATION, DEVELOPMENT, AND FUNCTIONING].

Science.gov (United States)

Korzun, V M; Balakhoiov, S V; Chpanin, E V; Denisov, A V; Mikhailov, E P; Mischenko, A J; Yarygina, M B; Rozhdestvensky, E N; Fomina, L A

2016-01-01

The paper gives the results of analyzing the data of long-term studies of the natural focal pattern of plague in the Gornyi Altai natural focus. It describes a wide range of biological processes occurring in the focus and shows the most important patterns of its functioning as a complex multilevel ecological system. The key features of the formation of the focus have been revealed. The plague focus in South-Western Altai has formed relatively, recently, about half a century ago, then it has intensively developed and its enzootic area and the activity of epizootic manifestations have considerably increased. This process is due to the space-time transformations of the basic ecological and population characteristics of Pallas' pika (Ochotoma pallasi), the principal vector of the pathogen of plague and fleas parasitizing the mammal, which is in turn related to the aridization of mountain steppes in South-Western Altai.

Ectoparasites of dogs belonging to people in resource-poor communities in North West Province, South Africa

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N.R. Bryson

2000-07-01

Full Text Available A total of 344 dogs belonging to people in resource-poor communities in North West Province, South Africa, was examined for ectoparasites, and all visible arthropods were collected from the left side of each dog. By doubling these numbers it was estimated that the dogs harboured 14 724 ixodid ticks, belonging to 6 species, 1028 fleas, belonging to 2 species, and 26 lice. Haemaphysalis leachi accounted for 420 and Rhipicephalus sanguineus for 14 226 of the ticks. Pure infestations of H. leachi were present on 14 dogs and of R. sanguineus on 172 dogs. Small numbers of Amblyomma hebraeum, R. appendiculatus, R. evertsi evertsi and R. simus were also collected. The predominance of R. sanguineus accounts for the high prevalence of canine ehrlichiosis (Ehrlichia canis within the survey region, compared to canine babesiosis (Babesia canis, which is transmitted by H. leachi, and is a much rarer disease.

Cryptic intercontinental colonization in water fleas Daphnia pulicaria inferred from phylogenetic analysis of mitochondrial DNA variation

Czech Academy of Sciences Publication Activity Database

Marková, Silvia; Dufresne, F.; Rees, D. J.; Černý, M.; Kotlík, Petr

2007-01-01

Roč. 44, - (2007), s. 42-52 ISSN 1055-7903 Grant - others:Grant Agency of Charles University(CZ) 197/2004-2005 Institutional research plan: CEZ:AV0Z50450515 Keywords : arctic * colonization * Daphnia pulex complex Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.994, year: 2007

Methyl farnesoate synthesis is necessary for the environmental sex determination in the water flea Daphnia pulex.

Science.gov (United States)

Toyota, Kenji; Miyakawa, Hitoshi; Hiruta, Chizue; Furuta, Kenjiro; Ogino, Yukiko; Shinoda, Tetsuro; Tatarazako, Norihisa; Miyagawa, Shinichi; Shaw, Joseph R; Iguchi, Taisen

2015-09-01

Sex-determination systems can be divided into two groups: genotypic sex determination (GSD) and environmental sex determination (ESD). ESD is an adaptive life-history strategy that allows control of sex in response to environmental cues in order to optimize fitness. However, the molecular basis of ESD remains largely unknown. The micro crustacean Daphnia pulex exhibits ESD in response to various external stimuli. Although methyl farnesoate (MF: putative juvenile hormone, JH, in daphnids) has been reported to induce male production in daphnids, the role of MF as a sex-determining factor remains elusive due to the lack of a suitable model system for its study. Here, we establish such a system for ESD studies in D. pulex. The WTN6 strain switches from producing females to producing males in response to the shortened day condition, while the MFP strain only produces females, irrespective of day-length. To clarify whether MF has a novel physiological role as a sex-determining factor in D. pulex, we demonstrate that a MF/JH biosynthesis inhibitor suppressed male production in WTN6 strain reared under the male-inducible condition, shortened day-length. Moreover, we show that juvenile hormone acid O-methyltransferase (JHAMT), a critical enzyme of MF/JH biosynthesis, displays MF-generating activity by catalyzing farnesoic acid. Expression of the JHAMT gene increased significantly just before the MF-sensitive period for male production in the WTN6 strain, but not in the MFP strain, when maintained under male-inducible conditions. These results suggest that MF synthesis regulated by JHAMT is necessary for male offspring production in D. pulex. Our findings provide novel insights into the genetic underpinnings of ESD and they begin to shed light on the physiological function of MF as a male-fate determiner in D. pulex. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ixodes ricinus ticks are reservoir hosts for Rickettsia helvetica and potentially carry flea-borne Rickettsia species.

NARCIS (Netherlands)

Sprong, H.; Wielinga, P.R.; Fonville, M.; Reusken, C.; Brandenburg, A.H.; Borgsteede, F.H.M.

2009-01-01

Background - Hard ticks have been identified as important vectors of rickettsiae causing the spotted fever syndrome. Tick-borne rickettsiae are considered to be emerging, but only limited data are available about their presence in Western Europe, their natural life cycle and their reservoir hosts.

SURVEILLANCE OF SEAPORT RODENTS AND ITS FLEA-INDICES IN CILACAP, CENTRAL JAVA AND PANJANG, SUMATERA, INDONESIA

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K. C. Megawe

2012-09-01

Full Text Available Suatu survai terhadap tikus dan pinjal telah diselenggarakan di daerah pelabuhan Cilacap dan Panjang, pada November 1985 sampai Maret 1986. Dalam survai itu diidentifikasi empat spesies tikus, yaitu Rattus r. diardii, R. norregicus, Bandicota indica, dan Mus musculus, serta seekor insektivora, Suncus murinus. Kepadatan polusi binatang-binatang ini rendah di dalam pelabuhan dan sedang di perkampungan sekitarnya. R.r. diardii terbukti merupakan tikus yang terbanyak dijumpai baik di pelabuhan maupun di perkampungan sekitar. Kepadatan Xenopsylla cheopis ternyata rendah baik pada tikus-tikus maupun insektivora di kedua daerah pelabuhan. Indeks pinjal spesifik tertinggi didapatkan pada R.r. diardii. Tes kerentanan X. cheopis terhadap insektisida dengan menggunakan DDT 4%, melathion 0,5% dan fenit rothion 1% menunjukkan bahwa pinjal itu lebih sensitif terhadap melathion dan fenitrothion dibanding terhadap DDT, di kedua daerah pelabuhan.

Inbreeding and adaptive plasticity: an experimental analysis on predator-induced responses in the water flea Daphnia

Science.gov (United States)

Swillen, Ine; Vanoverbeke, Joost; De Meester, Luc

2015-01-01

Several studies have emphasized that inbreeding depression (ID) is enhanced under stressful conditions. Additionally, one might imagine a loss of adaptively plastic responses which may further contribute to a reduction in fitness under environmental stress. Here, we quantified ID in inbred families of the cyclical parthenogen Daphnia magna in the absence and presence of fish predation risk. We test whether predator stress affects the degree of ID and if inbred families have a reduced capacity to respond to predator stress by adaptive phenotypic plasticity. We obtained two inbred families through clonal selfing within clones isolated from a fish pond. After mild purging under standardized conditions, we compared life history traits and adaptive plasticity between inbred and outbred lineages (directly hatched from the natural dormant egg bank of the same pond). Initial purging of lineages under standardized conditions differed among inbred families and exceeded that in outbreds. The least purged inbred family exhibited strong ID for most life history traits. Predator-induced stress hardly affected the severity of ID, but the degree to which the capacity for adaptive phenotypic plasticity was retained varied strongly among the inbred families. The least purged family overall lacked the capacity for adaptive phenotypic plasticity, whereas the family that suffered only mild purging exhibited a potential for adaptive plasticity that was comparable to the outbred population. We thus found that inbred offspring may retain the capacity to respond to the presence of fish by adaptive phenotypic plasticity, but this strongly depends on the parental clone engaging in selfing. PMID:26257883

Primer registro de Dasypsyllus (Avesopsylla lasius lasius (Siphonaptera: Ceratophyllidae en nidos de golondrina chilena, Tachycineta meyeni (Passeriformes: Hirundinidae, en Ushuaia (Tierra del Fuego, Argentina

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Rosana ARAMBURÚ

2009-01-01

Full Text Available La golondrina chilena, Tachycineta meyeni (Cabanis, nidifica en el centro de Chile y suroeste de Argentina. En invierno migra a Bolivia, Paraguay y al sureste de Brasil. Estas golondrinas ocuparon una serie de cajas-nido en Ushuaia, Tierra del Fuego. Luego de la temporada de cría, tratamos los nidos con acetato de etilo y los revisamos en búsqueda de artrópodos hematófagos. Encontramos pulgas adultas, que fueron fijadas, aclaradas, deshidratadas, diafanizadas y montadas en un derivado de clavo de olor para su observación al microsocopio óptico. Identificamos machos y hembras de Dasypsyllus (Avesopsylla lasius lasius (Rothschild. En Argentina, esta pulga es conocida solamente en Sierra de la Ventana (Buenos Aires, donde se la halló parasitando la golondrina barranquera, Notiochelidon cyanoleuca patagonica (Vieillot. La información disponible debería complementarse con prospecciones en localidades intermedias. Otras aves relacionadas con ambas golondrinas por la ocupación de nidos, como el rayadito (Aphrastura spinicauda (Gmelin, ratona común (Troglodytes aedon Vieillot, caminera común (Geositta cunicularia (Vieillot, hornero (Furnarius rufus (Gmelin, podrían contribuir a la dispersión de la pulga entre las dos localidades registradas.

Knowledge and practices related to plague in an endemic area of Uganda

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Kiersten J. Kugeler

2017-11-01

Full Text Available Background: Plague is a virulent zoonosis reported most commonly from Sub-Saharan Africa. Early treatment with antibiotics is important to prevent mortality. Understanding knowledge gaps and common behaviors informs the development of educational efforts to reduce plague mortality. Methods: A multi-stage cluster-sampled survey of 420 households was conducted in the plague-endemic West Nile region of Uganda to assess knowledge of symptoms and causes of plague and health care-seeking practices. Results: Most (84% respondents were able to correctly describe plague symptoms; approximately 75% linked plague with fleas and dead rats. Most respondents indicated that they would seek health care at a clinic for possible plague; however plague-like symptoms were reportedly common, and in practice, persons sought care for those symptoms at a health clinic infrequently. Conclusions: Persons in the plague-endemic region of Uganda have a high level of understanding of plague, yet topics for targeted educational messages are apparent. Keywords: Plague, Yersinia pestis, Knowledge, Practices, Behaviors, Africa

Avian pox in Magellanic Penguins (Spheniscus magellanicus).

Science.gov (United States)

Kane, Olivia J; Uhart, Marcela M; Rago, Virginia; Pereda, Ariel J; Smith, Jeffrey R; Van Buren, Amy; Clark, J Alan; Boersma, P Dee

2012-07-01

Avian pox is an enveloped double-stranded DNA virus that is mechanically transmitted via arthropod vectors or mucosal membrane contact with infectious particles or birds. Magellanic Penguins (Spheniscus magellanicus) from two colonies (Punta Tombo and Cabo Dos Bahías) in Argentina showed sporadic, nonepidemic signs of avian pox during five and two of 29 breeding seasons (1982-2010), respectively. In Magellanic Penguins, avian pox expresses externally as wart-like lesions around the beak, flippers, cloaca, feet, and eyes. Fleas (Parapsyllus longicornis) are the most likely arthropod vectors at these colonies. Three chicks with cutaneous pox-like lesions were positive for Avipoxvirus and revealed phylogenetic proximity with an Avipoxvirus found in Black-browed Albatross (Thalassarche melanophrys) from the Falkland Islands in 1987. This proximity suggests a long-term circulation of seabird Avipoxviruses in the southwest Atlantic. Avian pox outbreaks in these colonies primarily affected chicks, often resulted in death, and were not associated with handling, rainfall, or temperature.

Phylogenetic position of the North American isolate of Pasteuria that parasitizes the soybean cyst nematode, Heterodera glycines, as inferred from 16S rDNA sequence analysis.

Science.gov (United States)

Atibalentja, N; Noel, G R; Domier, L L

2000-03-01

A 1341 bp sequence of the 16S rDNA of an undescribed species of Pasteuria that parasitizes the soybean cyst nematode, Heterodera glycines, was determined and then compared with a homologous sequence of Pasteuria ramosa, a parasite of cladoceran water fleas of the family Daphnidae. The two Pasteuria sequences, which diverged from each other by a dissimilarity index of 7%, also were compared with the 16S rDNA sequences of 30 other bacterial species to determine the phylogenetic position of the genus Pasteuria among the Gram-positive eubacteria. Phylogenetic analyses using maximum-likelihood, maximum-parsimony and neighbour-joining methods showed that the Heterodera glycines-infecting Pasteuria and its sister species, P. ramosa, form a distinct line of descent within the Alicyclobacillus group of the Bacillaceae. These results are consistent with the view that the genus Pasteuria is a deeply rooted member of the Clostridium-Bacillus-Streptococcus branch of the Gram-positive eubacteria, neither related to the actinomycetes nor closely related to true endospore-forming bacteria.

Age at Vaccination May Influence Response to Sylvatic Plague Vaccine (SPV) in Gunnison's Prairie Dogs (Cynomys gunnisoni).

Science.gov (United States)

Rocke, Tonie E; Tripp, Dan; Lorenzsonn, Faye; Falendysz, Elizabeth; Smith, Susan; Williamson, Judy; Abbott, Rachel

2015-06-01

Gunnison's prairie dogs (Cynomys gunnisoni) have been considered at greater risk from Yersinia pestis (plague) infection in the montane portion of their range compared to populations at lower elevations, possibly due to factors related to flea transmission of the bacteria or greater host susceptibility. To test the latter hypothesis and determine whether vaccination against plague with an oral sylvatic plague vaccine (SPV) improved survival, we captured prairie dogs from a C. g. gunnisoni or "montane" population and a C. g. zuniensis or "prairie" population for vaccine efficacy and challenge studies. No differences (P = 0.63) were found in plague susceptibility in non-vaccinated animals between these two populations; however, vaccinates from the prairie population survived plague challenge at significantly higher rates (P plague challenge at a much higher rate than adults (P plague in the C. g. gunnisoni or "montane" populations of Gunnison's prairie dogs, and that SPV could be a useful plague management tool for this species, particularly if targeted at younger cohorts.

Knowledge and practices related to plague in an endemic area of Uganda.

Science.gov (United States)

Kugeler, Kiersten J; Apangu, Titus; Forrester, Joseph D; Griffith, Kevin S; Candini, Gordian; Abaru, Janet; Okoth, Jimmy F; Apio, Harriet; Ezama, Geoffrey; Okello, Robert; Brett, Meghan; Mead, Paul

2017-11-01

Plague is a virulent zoonosis reported most commonly from Sub-Saharan Africa. Early treatment with antibiotics is important to prevent mortality. Understanding knowledge gaps and common behaviors informs the development of educational efforts to reduce plague mortality. A multi-stage cluster-sampled survey of 420 households was conducted in the plague-endemic West Nile region of Uganda to assess knowledge of symptoms and causes of plague and health care-seeking practices. Most (84%) respondents were able to correctly describe plague symptoms; approximately 75% linked plague with fleas and dead rats. Most respondents indicated that they would seek health care at a clinic for possible plague; however plague-like symptoms were reportedly common, and in practice, persons sought care for those symptoms at a health clinic infrequently. Persons in the plague-endemic region of Uganda have a high level of understanding of plague, yet topics for targeted educational messages are apparent. Published by Elsevier Ltd.

Plague and Climate: Scales Matter

Science.gov (United States)

Ben Ari, Tamara; Neerinckx, Simon; Gage, Kenneth L.; Kreppel, Katharina; Laudisoit, Anne; Leirs, Herwig; Stenseth, Nils Chr.

2011-01-01

Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague system and is a likely factor to explain some of plague's variability from small and regional to large scales. Here, we review effects of climate variables on plague hosts and vectors from individual or population scales to studies on the whole plague system at a large scale. Upscaled versions of small-scale processes are often invoked to explain plague variability in time and space at larger scales, presumably because similar scale-independent mechanisms underlie these relationships. This linearity assumption is discussed in the light of recent research that suggests some of its limitations. PMID:21949648

INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp.) FROM YUCATAN, MEXICO.

Science.gov (United States)

Peniche-Lara, Gaspar; Ruiz-Piña, Hugo A; Reyes-Novelo, Enrique; Dzul-Rosado, Karla; Zavala-Castro, Jorge

2016-01-01

Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis) and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis) by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltA and 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1%) from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

Dracunculiasis in oral and maxillofacial surgery.

Science.gov (United States)

Kim, Soung Min

2016-04-01

Dracunculiasis, otherwise known as guinea worm disease (GWD), is caused by infection with the nematode Dracunculus medinensis. This nematode is transmitted to humans exclusively via contaminated drinking water. The transmitting vectors are Cyclops copepods (water fleas), which are tiny free-swimming crustaceans usually found abundantly in freshwater ponds. Humans can acquire GWD by drinking water that contains vectors infected with guinea worm larvae. This disease is prevalent in some of the most deprived areas of the world, and no vaccine or medicine is currently available. International efforts to eradicate dracunculiasis began in the early 1980s. Most dentists and maxillofacial surgeons have neglected this kind of parasite infection. However, when performing charitable work in developing countries near the tropic lines or other regions where GWD is endemic, it is important to consider GWD in cases of swelling or tumors of unknown origin. This paper reviews the pathogenesis, epidemiology, clinical criteria, diagnostic criteria, treatment, and prevention of dracunculiasis. It also summarizes important factors for maxillofacial surgeons to consider.

Feline hemotropic mycoplasmosis in jaguar (Panthera onca: case report

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Rafaela Guimarães Sanchioli

2015-05-01

Full Text Available Being often subject to stressful situations, animals kept in captivity are more susceptible to immunosuppression. When in the presence of concurrent infections or under situations of stress, Mycoplasma haemofelis may develop the clinical symptoms of feline hemotropic mycoplasmosis. The transmission of M. haemofelis occurs through hematophagous arthropod vectors, such as fleas, ticks, and lice. Infections range from hemolytic anemia with risk of imminent death to subtle chronic anemia. Administration of imidocarb to treat wild felines infected with hemoplasms may show greater effectiveness due to its injectable nature and smaller number of applications when compared to the use of doxycycline orally for a longer period. As a prophylactic measure for wild cats, environmental enrichment seems to be more effective when compared to other prevention ways usually adopted in domestic cats. This article aims to report a case of feline hemotropic mycoplasmosis in jaguar (Panthera onca and address its relation to the immunosuppression caused by stress conditions in captivity.

Determination of benzothiazole and alkylphosphates in water samples from the Great Lakes Drainage Basin by gas chromatography/atomic emission detection

Energy Technology Data Exchange (ETDEWEB)

Scott, B.F. [Environment Canada, Burlington, ON (Canada). Wastewater Technology Centre; Sverko, E.; Maguire, R.J. [Environment Canada, Burlington, ON (Canada). Wastewater Technology Centre

1996-06-01

Centrifuged water extracts from large receiving water bodies were analyzed for heteroatom-containing compounds. Extracts from aqueous environmental samples were analyzed by gas chromatography/atomic emission detection for P-, S-, and N- containing compounds. The samples exhibited complex chromatographic traces. Benzothiazole, tri-n-butylphosphate, tris(2-chloroethyl)phosphate, tris({beta}-chloroisopropyl)phosphate and two isomers of this last chemical were detected in all archived water extracts collected from permanent sampling stations at Fort Erie, Niagara-on-the-Lake and Wolfe Island. The concentrations of the trialkylphosphates reported in this study were at least four orders of magnitude lower than concentrations of some other trialkylphosphates and triarylphosphates that cause acute toxicity to rainbow trout, water fleas, midge larvae and shrimp. Further work on trialkylphosphates is under way to assess their environmental distribution, their levels in industrial and municipal effluents and their acute and chronic toxicity to aquatic organisms. 32 refs., 3 tabs., 5 figs.

INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp. FROM YUCATAN, MEXICO

Directory of Open Access Journals (Sweden)

Gaspar PENICHE-LARA

2016-01-01

Full Text Available Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltAand 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1% from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

Aquatic Nuisance Species Locator

Science.gov (United States)

Data in this map has been collected by the United States Geological Survey's Nonindigenous Aquatic Species program located in Gainesville, Florida (http://nas.er.usgs.gov/default.aspx). This dataset may have some inaccuracies and is only current to June 15, 2012. The species identified in this dataset are not inclusive of all aquatic nuisance species, but rather a subset identified to be at risk for transport by recreational activities such as boating and angling. Additionally, the locations where organisims have been identified are also not inclusive and should be treated as a guide. Organisms are limited to the following: American bullfrog, Asian clam, Asian shore crab, Asian tunicate, Australian spotted jellyfish, Chinese mitten crab, New Zealand mudsnail, Colonial sea squirt, Alewife, Bighead carp, Black carp, Flathead catfish, Grass carp, Green crab, Lionfish, Northern snakehead, Quagga mussel, Round Goby, Ruffe, Rusty crayfish, Sea lamprey, Silver carp, Spiny water flea, Veined rapa whelk, Zebra mussel

Control of sugar beet pests at early season by seed treatment with insecticides

Directory of Open Access Journals (Sweden)

Kereši Tatjana

2006-01-01

Full Text Available In the period 2001-2004, experiments were conducted in the region of Bačka (northern Serbia to assess the efficiency of insecticide treatment of sugar beet seeds in controlling soil pests (larvae of Elateridae family and reducing the damage caused by beet weevil (Bothynoderes punctiventris G e r m and flea beetle (Chaetocnema tibialis I l l i g. Several insecticides mostly systemic ones (carbofuran, thiamethoxam, fipronil, imidacloprid and clothianidin, and their combinations with pyrethroids in different doses were tested in field conditions. Stand density, percentages of plants damaged by B. punctiventris and C. tibialis, injury level and weight of juvenile plants served as parameters for evaluation of insecticide efficiency. Most of the insecticides applied to seeds provided a significantly better stand density compared with the untreated control. Because of their systemic action, imidacloprid, thiamethoxam and their mixtures with pyrethroids provided very good protection of juvenile plants from C. tibialis and in some cases from B. punctiventris.

Myxomatosis: the occurrence of antibody to a soluble antigen of myxoma virus in wild rabbits, Oryctolagus cuniculus (L.), in Victoria, Australia.

Science.gov (United States)

Edmonds, J W; Shepherd, R C; Nolan, I F

1978-10-01

The occurrence of antibody of myxoma virus in wild rabbits following epizootics is highest in the semi-arid north-west of Victoria and lowest in temperate southern Victoria. Occurrence ranges up to about 90% in the north-west and to about 70% in the south except on the Western Plains where epizootics are rare and antibody occurrence seldom exceeds 30%. The establishment of the European rabbit flea may be changing the pattern of occurrence of antibody in the north-west by causing spring outbreaks of myxomatosis. It is suggested that the effects of the replacement of a simple recurring system of epizootic and breeding season several months apart by the occurrence of myxomatosis twice in the same year, once coincident with the breeding season, will be complex. The occurrence of detectable antibody may be less dependent on the infection rate and may be dependent to some extent on the relative timing of spring myxomatosis and the breeding season.

The toxicogenomic multiverse: convergent recruitment of proteins into animal venoms.

Science.gov (United States)

Fry, Bryan G; Roelants, Kim; Champagne, Donald E; Scheib, Holger; Tyndall, Joel D A; King, Glenn F; Nevalainen, Timo J; Norman, Janette A; Lewis, Richard J; Norton, Raymond S; Renjifo, Camila; de la Vega, Ricardo C Rodríguez

2009-01-01

Throughout evolution, numerous proteins have been convergently recruited into the venoms of various animals, including centipedes, cephalopods, cone snails, fish, insects (several independent venom systems), platypus, scorpions, shrews, spiders, toxicoferan reptiles (lizards and snakes), and sea anemones. The protein scaffolds utilized convergently have included AVIT/colipase/prokineticin, CAP, chitinase, cystatin, defensins, hyaluronidase, Kunitz, lectin, lipocalin, natriuretic peptide, peptidase S1, phospholipase A(2), sphingomyelinase D, and SPRY. Many of these same venom protein types have also been convergently recruited for use in the hematophagous gland secretions of invertebrates (e.g., fleas, leeches, kissing bugs, mosquitoes, and ticks) and vertebrates (e.g., vampire bats). Here, we discuss a number of overarching structural, functional, and evolutionary generalities of the protein families from which these toxins have been frequently recruited and propose a revised and expanded working definition for venom. Given the large number of striking similarities between the protein compositions of conventional venoms and hematophagous secretions, we argue that the latter should also fall under the same definition.

Wavefront division digital holography

Science.gov (United States)

Zhang, Wenhui; Cao, Liangcai; Li, Rujia; Zhang, Hua; Zhang, Hao; Jiang, Qiang; Jin, Guofan

2018-05-01

Digital holography (DH), mostly Mach-Zehnder configuration based, belongs to non-common path amplitude splitting interference imaging whose stability and fringe contrast are environmental sensitive. This paper presents a wavefront division DH configuration with both high stability and high-contrast fringes benefitting from quasi common path wavefront-splitting interference. In our proposal, two spherical waves with similar curvature coming from the same wavefront are used, which makes full use of the physical sampling capacity of the detectors. The interference fringe spacing can be adjusted flexibly for both in-line and off-axis mode due to the independent modulation to these two waves. Only a few optical elements, including the mirror-beam splitter interference component, are used without strict alignments, which makes it robust and easy-to-implement. The proposed wavefront division DH promotes interference imaging physics into the practical and miniaturized a step forward. The feasibility of this method is proved by the imaging of a resolution target and a water flea.

[Macro- and microevolution as related to the problem of origin and global expansion of the plague pathogen Yersinia pestis].

Science.gov (United States)

Suntsov, V V; Suntsova, N I

2008-01-01

The ratio of macro- and microevolutionary processes is considered with reference to the ecological scenario of the origin of the plague pathogen and its subsequent natural and anthropogenic global expansion. The macroevolutionary transformation of the ancestral pseudotuberculosis microbe clone into the initial plague microbe Yersinia pestis tarbagani occurred in Central Asia at the end of the Late Pleistocene by a "vertical" Darwinian way in an inadaptive heterothermal continual intermediate environment--the Mongolian marmot Marmota sibirica-flea Oropsylla silantiewi system--via a sequence of unstable and currently extinct intermediate forms. Its natural geographic expansion on the "oil spot" principle in the postglacial time led to the microevolutionary formation of 20-30 hostal subspecies circulating in populations of the background species of burrowing rodents and pikas in arid areas of Eurasia. The intercontinental spread of the "marmot" and "rat" pathogen subspecies in the past few centuries has been exclusively anthropogenic, with the involvement of synanthropic (ship) rats.

Impact of Twitter intensity, time, and location on message lapse of bluebird's pursuit of fleas in Madagascar.

Science.gov (United States)

Da'ar, Omar B; Yunus, Faisel; Md Hossain, Nassif; Househ, Mowafa

The recent outbreak of bubonic plague in Madagascar reminds us of the continuing public health challenges posed by such deadly diseases in various parts of the world years after their eradication. This study examines the role of Twitter in public health disease surveillance with special focus on how Twitter intensity, time, and location issues explain Twitter plague message delay. We retrospectively analyzed the Twitter feeds of the 2014 bubonic plague outbreak in Madagascar. The analyses are based on the plague-related data available in the public domain between November 19th and 27th 2014. The data were compiled in March 2015. We calculated the time differential between the tweets and retweets, and analyzed various characteristics of the Tweets including Twitter intensity of the users. A total of 6873 Twitter users were included in the study, of which 52% tweeted plague-related information during the morning hours (before mid-day), and 87% of the tweets came from the west of the epicenter of the plague. More importantly, while session of tweet lease and relative location had effect on message lapse, absolute location did not. Additionally, we found no evidence of differential effect of location on message lapse based on relative location i.e. tweets from west or east nor number of following. However, there is evidence that more intense Twitter use appears to have significant effect on message lapse such that as the number of tweets became more intense, time differential between the tweets and retweets increased while higher number of retweets diminished message lapse. This study affirms that Twitter can play an important role in ongoing disease surveillance and the timely dissemination of information during public health emergencies independent of the time and space restrictions. Further ways should be explored to embed social media channels in routine public health practice. Copyright © 2017 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.