Antibodies from malaria-exposed pregnant women recognize trypsin resistant epitopes on the surface of Plasmodium falciparum-infected erythrocytes selected for adhesion to chondroitin sulphate A

DEFF Research Database (Denmark)

Sharling, Lisa; Enevold, Anders; Sowa, Kordai M P

2004-01-01

of CSA binding and surface recognition of CSA selected parasites by serum IgG from malaria exposed pregnant women. Thus, the complete molecular definition of an antigenic P. falciparum erythrocyte surface protein that can be used as a malaria in pregnancy vaccine has not yet been achieved.......-specific antibodies induced as a result of pregnancy associated malaria (PAM). METHODS: Fluorescence activated cell sorting (FACS) was used to measure the levels of adult Scottish and Ghanaian male, and Ghanaian pregnant female plasma immunoglobulin G (IgG) that bind to the surface of infected erythrocytes. P....... falciparum infected erythrocytes selected for adhesion to CSA were found to express trypsin-resistant VSA that are the target of naturally acquired antibodies from pregnant women living in a malaria endemic region of Ghana. However in vitro adhesion to CSA and HA was relatively trypsin sensitive. An improved...

Protection of man: the exposed individual

Energy Technology Data Exchange (ETDEWEB)

Bohnstedt, A.; Knebel, J.U. [Programme Nuclear Safety Research, Karlsruhe Institute of Technology, Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Breustedt, B. [Institute for Radiation Research, Karlsruhe Institute of Technology, Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2010-07-01

Present methods for quantifying radiation exposure rely on a standardized reference man (75 kg) with defined average anatomical and physiological data. But individual person actually exposed differs from this idealized standard man. Therefore the focus of investigations at the Institute for Radiation Research (Institut fuer Strahlenforschung, ISF) which was founded at Karlsruhe Institute of Technology (Karlsruher Institut fuer Technologie, KIT) in 2009 is based on the vision to place the exposed individual with its anatomical and physiological particularities, under consideration of age, gender, body height, body shape and environment, in the centre of an individual-related quantification of the external and internal radiation exposure. Research work at the ISF is aiming at quantifying radiation exposure by improved determination of doses essentially caused by external radiation fields and the intake of radionuclides into the body. The three main topics of the institute are - external dosimetry (e.g. using a (voxel) model of the hand to simulate skin dose distribution); - internal dosimetry (e.g. body size related efficiency calibration of in-vivo counting equipment); - numerical methods/modeling (e.g. development of a mathematical/voxel-hybrid model of the human body). (authors)

Ranking malaria risk factors to guide malaria control efforts in African highlands.

Directory of Open Access Journals (Sweden)

Natacha Protopopoff

Full Text Available INTRODUCTION: Malaria is re-emerging in most of the African highlands exposing the non immune population to deadly epidemics. A better understanding of the factors impacting transmission in the highlands is crucial to improve well targeted malaria control strategies. METHODS AND FINDINGS: A conceptual model of potential malaria risk factors in the highlands was built based on the available literature. Furthermore, the relative importance of these factors on malaria can be estimated through "classification and regression trees", an unexploited statistical method in the malaria field. This CART method was used to analyse the malaria risk factors in the Burundi highlands. The results showed that Anopheles density was the best predictor for high malaria prevalence. Then lower rainfall, no vector control, higher minimum temperature and houses near breeding sites were associated by order of importance to higher Anopheles density. CONCLUSIONS: In Burundi highlands monitoring Anopheles densities when rainfall is low may be able to predict epidemics. The conceptual model combined with the CART analysis is a decision support tool that could provide an important contribution toward the prevention and control of malaria by identifying major risk factors.

Alteration of the retinoblastoma gene locus in radium-exposed individuals

International Nuclear Information System (INIS)

Hardwick, J.P.; Schlenker, R.; Huberman, E.

1991-01-01

This study was performed to determine if the retinoblastoma suppressor gene was altered in individuals exposed to radium. We analyzed the Rb gene in 30 individuals, 17 of whom were exposed to radium either occupationally or iatrogenically. In the kidney DNA from four of nine radium-exposed individuals, the Rb gene was deleted. Three of these alterations in the Rb gene were internal deletions, which resulted in the absence of Rb mRNA accumulation. These results imply that the Rb gene is susceptible to radium-induced damage and confirm previous showing that radiation preferentially causes genomic deletions. The pronounced alterations in the non-tumorigenic femurs from radium-exposed individuals suggests that in the many years of exposure there was a selection of cells with alterations, presumably because of their growth advantage. Also it implies that deletions of one of the Rb alleles can be one of the events (perhaps an initial one) in the progression of radium-induced sarcomas. 11 refs., 2 figs

Dose coefficients for individual occupationally exposed

International Nuclear Information System (INIS)

2005-11-01

This Regulation refers to the requirements of the Regulation CNEN-NN.3.01, 'Basic Act of Radiological Protection', aiming its application to the dose calculation, with purposes of conformity verification with limits and restrictions of doses and level of reference for individual occupationally exposed, according to the express in its section 5

Malaria parasitemia among asymptomatic infants seen in a malaria ...

African Journals Online (AJOL)

In clinical settings, management of malaria cases has primarily been centred on case definition, giving minimal consideration to the asymptomatic individuals who remain a major reservoir since they do not seek care. In malaria endemic areas, infants are likely to remain asymptomatic since they have partial immunity ...

Clinical malaria case definition and malaria attributable fraction in the highlands of western Kenya.

Science.gov (United States)

Afrane, Yaw A; Zhou, Guofa; Githeko, Andrew K; Yan, Guiyun

2014-10-15

In African highland areas where endemicity of malaria varies greatly according to altitude and topography, parasitaemia accompanied by fever may not be sufficient to define an episode of clinical malaria in endemic areas. To evaluate the effectiveness of malaria interventions, age-specific case definitions of clinical malaria needs to be determined. Cases of clinical malaria through active case surveillance were quantified in a highland area in Kenya and defined clinical malaria for different age groups. A cohort of over 1,800 participants from all age groups was selected randomly from over 350 houses in 10 villages stratified by topography and followed for two-and-a-half years. Participants were visited every two weeks and screened for clinical malaria, defined as an individual with malaria-related symptoms (fever [axillary temperature≥37.5°C], chills, severe malaise, headache or vomiting) at the time of examination or 1-2 days prior to the examination in the presence of a Plasmodium falciparum positive blood smear. Individuals in the same cohort were screened for asymptomatic malaria infection during the low and high malaria transmission seasons. Parasite densities and temperature were used to define clinical malaria by age in the population. The proportion of fevers attributable to malaria was calculated using logistic regression models. Incidence of clinical malaria was highest in valley bottom population (5.0% cases per 1,000 population per year) compared to mid-hill (2.2% cases per 1,000 population per year) and up-hill (1.1% cases per 1,000 population per year) populations. The optimum cut-off parasite densities through the determination of the sensitivity and specificity showed that in children less than five years of age, 500 parasites per μl of blood could be used to define the malaria attributable fever cases for this age group. In children between the ages of 5-14, a parasite density of 1,000 parasites per μl of blood could be used to define the

Prevalence of sickle cell, malaria and glucose-6-phosphate ...

African Journals Online (AJOL)

PD) deficiency are relatively common genetic disorders in population exposed to malaria in sub-Saharan Africa. The prevalence of these two genetic disorders differs between different malaria transmission areas. Objectives: This cross ...

Can plant biotechnology help break the HIV-malaria link?

Science.gov (United States)

Vamvaka, E; Twyman, R M; Christou, P; Capell, T

2014-01-01

The population of sub-Saharan Africa is at risk from multiple, poverty-related endemic diseases. HIV and malaria are the most prevalent, but they disproportionately affect different groups of people, i.e. HIV predominantly affects sexually-active adults whereas malaria has a greater impact on children and pregnant women. Nevertheless, there is a significant geographical and epidemiological overlap which results in bidirectional and synergistic interactions with important consequences for public health. The immunosuppressive effects of HIV increase the risk of infection when individuals are exposed to malaria parasites and also the severity of malaria symptoms. Similarly, acute malaria can induce a temporary increase in the HIV viral load. HIV is associated with a wide range of opportunistic infections that can be misdiagnosed as malaria, resulting in the wasteful misuse of antimalarial drugs and a failure to address the genuine cause of the disease. There is also a cumulative risk of toxicity when antiretroviral and antimalarial drugs are given to the same patients. Synergistic approaches involving the control of malaria as a strategy to fight HIV/AIDS and vice versa are therefore needed in co-endemic areas. Plant biotechnology has emerged as a promising approach to tackle poverty-related diseases because plant-derived drugs and vaccines can be produced inexpensively in developing countries and may be distributed using agricultural infrastructure without the need for a cold chain. Here we explore some of the potential contributions of plant biotechnology and its integration into broader multidisciplinary public health programs to combat the two diseases in developing countries. Copyright © 2014 Elsevier Inc. All rights reserved.

Methylomic changes in individuals with psychosis, prenatally exposed to endocrine disrupting compounds: Lessons from diethylstilbestrol.

Directory of Open Access Journals (Sweden)

Fabrice Rivollier

Full Text Available In the Western world, between 1940 and 1970, more than 2 million people were exposed in utero to diethylstilbestrol (DES. In exposed individuals, and in their descendants, adverse outcomes have been linked to such exposure, including cancers, genital malformations, and less consistently, psychiatric disorders. We aimed to explore whether prenatal DES exposure would be associated with DNA methylation changes, and whether these epigenetic modifications would be associated with increased risk of psychosis.From 247 individuals born from mothers exposed to DES, we selected 69 siblings from 30 families. In each family, at least one sibling was exposed in utero to DES. We performed a methylome-wide association study using HumanMethylation450 DNA Analysis BeadChip® in peripheral blood. We analyzed methylation changes at individual CpGs or regions in exposed (n = 37 versus unexposed individuals (n = 32. We also compared exposed individuals with (n = 7 and without psychosis (n = 30.There were more individuals with schizophrenia in the DES-exposed group. We found no significant differences between exposed and unexposed individuals with respect to differentially methylated CpGs or regions. The largest difference was in a region near the promoter of an ADAMTS proteoglycanase gene (ADAMTS9. Compared to exposed individuals without psychosis, exposed individuals with psychosis had differential methylation in the region encompassing the gene encoding the zinc finger protein 57 (ZFP57.In utero exposure to DES was not associated with methylation changes at specific CpG or regions. In exposed individuals, however, psychosis was associated with specific methylomic modifications that could impact neurodevelopment and neuroplasticity.

Linking individual phenotype to density-dependent population growth: the influence of body size on the population dynamics of malaria vectors

Science.gov (United States)

Russell, Tanya L.; Lwetoijera, Dickson W.; Knols, Bart G. J.; Takken, Willem; Killeen, Gerry F.; Ferguson, Heather M.

2011-01-01

Understanding the endogenous factors that drive the population dynamics of malaria mosquitoes will facilitate more accurate predictions about vector control effectiveness and our ability to destabilize the growth of either low- or high-density insect populations. We assessed whether variation in phenotypic traits predict the dynamics of Anopheles gambiae sensu lato mosquitoes, the most important vectors of human malaria. Anopheles gambiae dynamics were monitored over a six-month period of seasonal growth and decline. The population exhibited density-dependent feedback, with the carrying capacity being modified by rainfall (97% wAICc support). The individual phenotypic expression of the maternal (p = 0.0001) and current (p = 0.040) body size positively influenced population growth. Our field-based evidence uniquely demonstrates that individual fitness can have population-level impacts and, furthermore, can mitigate the impact of exogenous drivers (e.g. rainfall) in species whose reproduction depends upon it. Once frontline interventions have suppressed mosquito densities, attempts to eliminate malaria with supplementary vector control tools may be attenuated by increased population growth and individual fitness. PMID:21389034

Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data

Science.gov (United States)

Unger, Holger W.; Briand, Valerie; Fievet, Nadine; Landis, Sarah H.; Adu-Afarwuah, Seth; Dewey, Kathryn G.; ter Kuile, Feiko O.; Desai, Meghna; Ouma, Peter; Gutman, Julie; Oneko, Martina; Slutsker, Laurence; Kariuki, Simon; Ayisi, John; Madanitsa, Mwayiwawo; Mwapasa, Victor; Ashorn, Per; Mueller, Ivo; Stanisic, Danielle; Lusingu, John P. A.; van Eijk, Anna Maria; Adair, Linda; Cole, Stephen R.; Westreich, Daniel; Meshnick, Steven

2017-01-01

Background Four studies previously indicated that the effect of malaria infection during pregnancy on the risk of low birthweight (LBW; Malnutrition (M3) initiative using a convenience sampling approach and were eligible for pooling given adequate ethical approval and availability of essential variables. Study-specific adjusted effect estimates were calculated using inverse probability of treatment-weighted linear and log-binomial regression models and pooled using a random-effects model. The adjusted risk of delivering a baby with LBW was 8.8% among women with malaria infection at antenatal enrollment compared to 7.7% among uninfected women (adjusted risk ratio [aRR] 1.14 [95% confidence interval (CI): 0.91, 1.42]; N = 13,613), 10.5% among women with malaria infection at delivery compared to 7.9% among uninfected women (aRR 1.32 [95% CI: 1.08, 1.62]; N = 11,826), and 15.3% among women with low mid-upper arm circumference (MUAC malnutrition. The major limitations of the study included availability of only 2 cross-sectional measurements of malaria and the limited availability of ultrasound-based pregnancy dating to assess impacts on preterm birth and fetal growth in all studies. Conclusions Pregnant women with malnutrition and malaria infection are at increased risk of LBW compared to women with only 1 risk factor or none, but malaria and malnutrition do not act synergistically. PMID:28792500

Chronic Exposure to Malaria Is Associated with Inhibitory and Activation Markers on Atypical Memory B Cells and Marginal Zone-Like B Cells

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Itziar Ubillos

2017-08-01

Full Text Available In persistent infections that are accompanied by chronic immune activation, such as human immunodeficiency virus, hepatitis C virus, and malaria, there is an increased frequency of a phenotypically distinct subset of memory B cells lacking the classic memory marker CD27 and showing a reduced capacity to produce antibodies. However, critical knowledge gaps remain on specific B cell changes and immune adaptation in chronic infections. We hypothesized that expansion of atypical memory B cells (aMBCs and reduction of activated peripheral marginal zone (MZ-like B cells in constantly exposed individuals might be accompanied by phenotypic changes that would confer a tolerogenic profile, helping to establish tolerance to infections. To better understand malaria-associated phenotypic abnormalities on B cells, we analyzed peripheral blood mononuclear cells from 55 pregnant women living in a malaria-endemic area of Papua Nueva Guinea and 9 Spanish malaria-naïve individuals using four 11-color flow cytometry panels. We assessed the expression of markers of B cell specificity (IgG and IgM, activation (CD40, CD80, CD86, b220, TACI, and CD150, inhibition (PD1, CD95, and CD71, and migration (CCR3, CXCR3, and CD62l. We found higher frequencies of active and resting aMBC and marked reduction of MZ-like B cells, although changes in absolute cell counts could not be assessed. Highly exposed women had higher PD1+-, CD95+-, CD40+-, CD71+-, and CD80+-activated aMBC frequencies than non-exposed subjects. Malaria exposure increased frequencies of b220 and proapoptotic markers PD1 and CD95, and decreased expression of the activation marker TACI on MZ-like B cells. The increased frequencies of inhibitory and apoptotic markers on activated aMBCs and MZ-like B cells in malaria-exposed adults suggest an immune-homeostatic mechanism for maintaining B cell development and function while simultaneously downregulating hyperreactive B cells. This mechanism would keep the B cell

Knowledge, attitude, and practice about malaria: Socio-demographic implications for malaria control in rural Ghana.

Science.gov (United States)

Assan, Abraham; Takian, Amirhossein; Hanafi-Bojd, Ahmad Ali; Rahimiforoushani, Abbas; Nematolahi, Shahrzad

2017-11-01

Despite continuing international attention to malaria prevention, the disease remains a global public health problem. We investigated socio-demographic factors influencing knowledge, attitudes, and practices about malaria in rural Ghana. Our survey looked at 354 households. Mean knowledge score was higher among individuals with a history of volunteers having visited their households to educate them about malaria; families with 4-6 members; and males. Households with at least one under-five-aged child also had significantly higher knowledge scores. Households with at least one pregnant woman evinced a positive attitude towards malaria prevention. National malaria control strategies have achieved positive results in the fight against malaria. Nonetheless, multipronged community-based health strategies that integrate malaria programs and population growth control initiatives may be able to reach by 2030 the sustainable development goal of eliminating malaria.

Effect of lead exposure on the immune response of some occupationally exposed individuals

International Nuclear Information System (INIS)

Mishra, Kamla Prasad; Singh, Vijay Kumar; Rani, Reena; Yadav, Virendra Singh; Chandran, Vinod; Srivastava, Satya Prakash; Seth, Prahlad Kishore

2003-01-01

Lead is a ubiquitous pollutant in the industrial environment, which poses serious threats to human health. In the past 20 years increasing attention has been paid to the effects of lead exposure on health. This toxic metal alters the immune response of animals as well as humans. To study the immunological effects of occupational exposure to lead, we examined lymphocyte proliferation, natural killer (NK) cell cytotoxicity and interferon-γ production with peripheral blood mononuclear cells (PBMCs) of individuals occupationally exposed to lead. We selected three different groups of individuals exposed to lead: three-wheeler drivers (30), battery workers (34) and silver jewelery makers (20); and unexposed healthy volunteers (30) as control for comparison. Our results indicate that though lymphocyte proliferation to phytohaemagglutinin (PHA) is inhibited in lead exposed individuals as compared with unexposed volunteers, there is no correlation between inhibition of lymphocyte proliferation and blood lead level. NK cell cytotoxicity remains unaffected in individuals exposed to lead as compared with controls. On the other hand, we observed that interferon-γ (IFN-γ) was significantly elevated in T cell mitogen, PHA, stimulated PBMCs culture supernatant of lead exposed individuals. We found significant positive correlation between blood lead levels and IFN-γ produced in culture supernatant on stimulation with PHA. In brief, this study demonstrates that lead can affect the immune response of the occupationally exposed individuals such as three-wheeler drivers, battery reconditioning workers and silver jewelery makers

Cotrimoxazole prophylactic treatment prevents malaria in children in sub-Saharan Africa: systematic review and meta-analysis.

Science.gov (United States)

Mbeye, Nyanyiwe M; ter Kuile, Feiko O; Davies, Mary-Ann; Phiri, Kamija S; Egger, Matthias; Wandeler, Gilles

2014-09-01

Cotrimoxazole prophylactic treatment (CPT) prevents opportunistic infections in HIV-infected or HIV-exposed children, but estimates of the effectiveness in preventing malaria vary. We reviewed studies that examined the effect of CPT on incidence of malaria in children in sub-Saharan Africa. We searched PubMed and EMBASE for randomised controlled trials (RCTs) and cohort studies on the effect of CPT on incidence of malaria and mortality in children and extracted data on the prevalence of sulphadoxine-pyrimethamine resistance-conferring point mutations. Incidence rate ratios (IRR) from individual studies were combined using random effects meta-analysis; confounder-adjusted estimates were used for cohort studies. The importance of resistance was examined in meta-regression analyses. Three RCTs and four cohort studies with 5039 children (1692 HIV-exposed; 2800 HIV-uninfected; 1486 HIV-infected) were included. Children on CPT were less likely to develop clinical malaria episodes than those without prophylaxis (combined IRR 0.37, 95% confidence interval: 0.21-0.66), but there was substantial between-study heterogeneity (I-squared = 94%, P < 0.001). The protective efficacy of CPT was highest in an RCT from Mali, where the prevalence of antifolate resistant plasmodia was low. In meta-regression analyses, there was some evidence that the efficacy of CPT declined with increasing levels of resistance. Mortality was reduced with CPT in an RCT from Zambia, but not in a cohort study from Côte d'Ivoire. Cotrimoxazole prophylactic treatment reduces incidence of malaria and mortality in children in sub-Saharan Africa, but study designs, settings and results were heterogeneous. CPT appears to be beneficial for HIV-infected and HIV-exposed as well as HIV-uninfected children. © 2014 John Wiley & Sons Ltd.

Malaria care seeking behavior of individuals in Ghana under the NHIS: Are we back to the use of informal care?

Science.gov (United States)

Fenny, Ama Pokuaa; Asante, Felix A; Enemark, Ulrika; Hansen, Kristian S

2015-04-12

Malaria is Ghana's most endemic disease; occurring across most parts of the country with a significant impact on individuals and the health system as whole. Treatment seeking for malaria care takes various forms. The National Health Insurance Scheme (NHIS) was introduced in 2004 to promote access to health services to mitigate the negative impact of the user fee regime. Ten years on, national coverage is less than 40% of the total population and patients continue to make direct payments for health services. This paper analyses the care-seeking behaviour of households for treatment of malaria in Ghana under the NHI policy. Using a cross-sectional survey of household data collected from three districts in Ghana covering the 3 ecological zones namely the coastal, forest and savannah, a multinomial logit model is estimated. The sample consists of 365 adults and children reporting being ill with malaria in the last four weeks prior to the study. Out of the total, 58% were insured and 71% of them sought care from a formal health facility. Among the insured, 15% chose informal care compared to 48% among the uninsured. The results from the multinomial logit estimations show that health insurance and travel time to health facility are significant determinants of health care demand. The results show that the insured are 6 times more likely to choose regional/district hospitals: 5 times more likely to choose health centres/clinics and 7 times more likely to choose private hospitals/clinics over informal care when compared with the uninsured. Individual characteristics such as age, education and wealth status were significant determinants of health care provider choice for specific categories of health facilities. Overall, for malaria care the uninsured are more likely to choose informal care compared to the insured for the treatment of malaria.

Importance of adequate local spatiotemporal transmission measures in malaria cohort studies: application to the relation between placental malaria and first malaria infection in infants.

Science.gov (United States)

Le Port, Agnès; Cottrell, Gilles; Chandre, Fabrice; Cot, Michel; Massougbodji, Achille; Garcia, André

2013-07-01

According to several studies, infants whose mothers had a malaria-infected placenta (MIP) at delivery are at increased risk of a first malaria infection. Immune tolerance caused by intrauterine contact with the parasite could explain this phenomenon, but it is also known that infants who are highly exposed to Anopheles mosquitoes infected with Plasmodium are at greater risk of contracting malaria. Consequently, local malaria transmission must be taken into account to demonstrate the immune tolerance hypothesis. From data collected between 2007 and 2010 on 545 infants followed from birth to age 18 months in southern Benin, we compared estimates of the effect of MIP on time to first malaria infection obtained through different Cox models. In these models, MIP was adjusted for either 1) "village-like" time-independent exposure variables or 2) spatiotemporal exposure prediction derived from local climatic, environmental, and behavioral factors. Only the use of exposure prediction improved the model's goodness of fit (Bayesian Information Criterion) and led to clear conclusions regarding the effect of placental infection, whereas the models using the village-like variables were less successful than the univariate model. This demonstrated clearly the benefit of adequately taking transmission into account in cohort studies of malaria.

Malaria in Brazil, Colombia, Peru and Venezuela: current challenges in malaria control and elimination.

Science.gov (United States)

Recht, Judith; Siqueira, André M; Monteiro, Wuelton M; Herrera, Sonia M; Herrera, Sócrates; Lacerda, Marcus V G

2017-07-04

In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an important public health concern in the region. Most malaria cases in South America come from Amazon rain forest areas in northern countries, where more than half of malaria is caused by Plasmodium vivax, while Plasmodium falciparum malaria incidence has decreased in recent years. This review discusses current malaria data, policies and challenges in four South American Amazon countries: Brazil, Colombia, Peru and the Bolivarian Republic of Venezuela. Challenges to continuing efforts to further decrease malaria incidence in this region include: a significant increase in malaria cases in recent years in Venezuela, evidence of submicroscopic and asymptomatic infections, peri-urban malaria, gold mining-related malaria, malaria in pregnancy, glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine use, and possible under-detection of Plasmodium malariae. Some of these challenges underscore the need to implement appropriate tools and procedures in specific regions, such as a field-compatible molecular malaria test, a P. malariae-specific test, malaria diagnosis and appropriate treatment as part of regular antenatal care visits, G6PD test before primaquine administration for P. vivax cases (with weekly primaquine regimen for G6PD deficient individuals), single low dose of primaquine for P. falciparum malaria in Colombia, and national and regional efforts to contain malaria spread in Venezuela urgently needed especially in mining areas. Joint efforts and commitment towards malaria control and elimination should be strategized based on examples of successful regional malaria fighting initiatives, such as PAMAFRO and RAVREDA/AMI.

Unstable malaria in Sudan: the influence of the dry season. Malaria in areas of unstable and seasonal transmission. Lessons from Daraweesh

DEFF Research Database (Denmark)

Theander, T G

1999-01-01

Most studies of the natural history of Plasmodium falciparum infection have been performed in areas of stable malaria transmission and the acquisition of immunity to malaria in individuals who live in such areas is well documented. For the past 10 years, we have monitored host-parasite relationsh......Most studies of the natural history of Plasmodium falciparum infection have been performed in areas of stable malaria transmission and the acquisition of immunity to malaria in individuals who live in such areas is well documented. For the past 10 years, we have monitored host...

Malaria, Epstein-Barr virus infection and the pathogenesis of Burkitt's lymphoma.

Science.gov (United States)

Mawson, Anthony R; Majumdar, Suvankar

2017-11-01

A geographical and causal connection has long been recognized between malaria, Epstein-Barr virus (EBV) infection and Burkitt's lymphoma (BL), but the underlying mechanisms remain obscure. Potential clues are that the malaria parasite Plasmodium falciparum selectively absorbs vitamin A from the host and depends on it for its biological activities; secondly, alterations in vitamin A (retinoid) metabolism have been implicated in many forms of cancer, including BL. The first author has proposed that the merozoite-stage malaria parasite, emerging from the liver, uses its absorbed vitamin A as a cell membrane destabilizer to invade the red blood cells, causing anemia and other signs and symptoms of the disease as manifestations of an endogenous form of hypervitaminosis A (Mawson AR, Path Global Health 2013;107(3):122-9). Repeated episodes of malaria would therefore be expected to expose the tissues of affected individuals to potentially toxic doses of vitamin A. It is proposed that such episodes activate latent EBV infection, which in turn activates retinoid-responsive genes. Expression of these genes enhances viral replication and induces germinal center (GC) B cell expansion, activation-induced cytidine deaminase (AID) expression, and c-myc translocation, which in turn predisposes to BL. Thus, an endogenous form of retinoid toxicity related to malaria infection may be the common factor linking frequent malaria, EBV infection and BL, whereby prolonged exposure of lymphatic tissues to high concentrations of retinoids may combine to induce B-cell translocation and increase the risk of Burkitt's lymphoma. © 2017 UICC.

Predicting malaria vector distribution under climate change scenarios in China: Challenges for malaria elimination

Science.gov (United States)

Ren, Zhoupeng; Wang, Duoquan; Ma, Aimin; Hwang, Jimee; Bennett, Adam; Sturrock, Hugh J. W.; Fan, Junfu; Zhang, Wenjie; Yang, Dian; Feng, Xinyu; Xia, Zhigui; Zhou, Xiao-Nong; Wang, Jinfeng

2016-02-01

Projecting the distribution of malaria vectors under climate change is essential for planning integrated vector control activities for sustaining elimination and preventing reintroduction of malaria. In China, however, little knowledge exists on the possible effects of climate change on malaria vectors. Here we assess the potential impact of climate change on four dominant malaria vectors (An. dirus, An. minimus, An. lesteri and An. sinensis) using species distribution models for two future decades: the 2030 s and the 2050 s. Simulation-based estimates suggest that the environmentally suitable area (ESA) for An. dirus and An. minimus would increase by an average of 49% and 16%, respectively, under all three scenarios for the 2030 s, but decrease by 11% and 16%, respectively in the 2050 s. By contrast, an increase of 36% and 11%, respectively, in ESA of An. lesteri and An. sinensis, was estimated under medium stabilizing (RCP4.5) and very heavy (RCP8.5) emission scenarios. in the 2050 s. In total, we predict a substantial net increase in the population exposed to the four dominant malaria vectors in the decades of the 2030 s and 2050 s, considering land use changes and urbanization simultaneously. Strategies to achieve and sustain malaria elimination in China will need to account for these potential changes in vector distributions and receptivity.

Predicting malaria vector distribution under climate change scenarios in China: Challenges for malaria elimination.

Science.gov (United States)

Ren, Zhoupeng; Wang, Duoquan; Ma, Aimin; Hwang, Jimee; Bennett, Adam; Sturrock, Hugh J W; Fan, Junfu; Zhang, Wenjie; Yang, Dian; Feng, Xinyu; Xia, Zhigui; Zhou, Xiao-Nong; Wang, Jinfeng

2016-02-12

Projecting the distribution of malaria vectors under climate change is essential for planning integrated vector control activities for sustaining elimination and preventing reintroduction of malaria. In China, however, little knowledge exists on the possible effects of climate change on malaria vectors. Here we assess the potential impact of climate change on four dominant malaria vectors (An. dirus, An. minimus, An. lesteri and An. sinensis) using species distribution models for two future decades: the 2030 s and the 2050 s. Simulation-based estimates suggest that the environmentally suitable area (ESA) for An. dirus and An. minimus would increase by an average of 49% and 16%, respectively, under all three scenarios for the 2030 s, but decrease by 11% and 16%, respectively in the 2050 s. By contrast, an increase of 36% and 11%, respectively, in ESA of An. lesteri and An. sinensis, was estimated under medium stabilizing (RCP4.5) and very heavy (RCP8.5) emission scenarios. in the 2050 s. In total, we predict a substantial net increase in the population exposed to the four dominant malaria vectors in the decades of the 2030 s and 2050 s, considering land use changes and urbanization simultaneously. Strategies to achieve and sustain malaria elimination in China will need to account for these potential changes in vector distributions and receptivity.

Malaria vaccines and their potential role in the elimination of malaria

Directory of Open Access Journals (Sweden)

Greenwood Brian M

2008-12-01

Full Text Available Abstract Research on malaria vaccines is currently directed primarily towards the development of vaccines that prevent clinical malaria. Malaria elimination, now being considered seriously in some epidemiological situations, requires a different vaccine strategy, since success will depend on killing all parasites in the community in order to stop transmission completely. The feature of the life-cycles of human malarias that presents the greatest challenge to an elimination programme is the persistence of parasites as asymptomatic infections. These are an important source from which transmission to mosquitoes can occur. Consequently, an elimination strategy requires a community-based approach covering all individuals and not just those who are susceptible to clinical malaria. The progress that has been made in development of candidate malaria vaccines is reviewed. It is unlikely that many of these will have the efficacy required for complete elimination of parasites, though they may have an important role to play as part of future integrated control programmes. Vaccines for elimination must have a high level of efficacy in order to stop transmission to mosquitoes. This might be achieved with some pre-erythrocytic stage candidate vaccines or by targeting the sexual stages directly with transmission-blocking vaccines. An expanded malaria vaccine programme with such objectives is now a priority.

Differential positive selection of malaria resistance genes in three indigenous populations of Peninsular Malaysia.

Science.gov (United States)

Liu, Xuanyao; Yunus, Yushimah; Lu, Dongsheng; Aghakhanian, Farhang; Saw, Woei-Yuh; Deng, Lian; Ali, Mohammad; Wang, Xu; Nor, Fadzilah Mohd; Ghazali, Fadzilah; Rahman, Thuhairah Abdul; Shaari, Shahrul Azlin; Salleh, Mohd Zaki; Phipps, Maude E; Ong, Rick Twee-Hee; Xu, Shuhua; Teo, Yik-Ying; Hoh, Boon-Peng

2015-04-01

The indigenous populations from Peninsular Malaysia, locally known as Orang Asli, continue to adopt an agro-subsistence nomadic lifestyle, residing primarily within natural jungle habitats. Leading a hunter-gatherer lifestyle in a tropical jungle environment, the Orang Asli are routinely exposed to malaria. Here we surveyed the genetic architecture of individuals from four Orang Asli tribes with high-density genotyping across more than 2.5 million polymorphisms. These tribes reside in different geographical locations in Peninsular Malaysia and belong to three main ethno-linguistic groups, where there is minimal interaction between the tribes. We first dissect the genetic diversity and admixture between the tribes and with neighboring urban populations. Later, by implementing five metrics, we investigated the genome-wide signatures for positive natural selection of these Orang Asli, respectively. Finally, we searched for evidence of genomic adaptation to the pressure of malaria infection. We observed that different evolutionary responses might have emerged in the different Orang Asli communities to mitigate malaria infection.

Salivary Secretion and Composition in Malaria: A Case-control Study

African Journals Online (AJOL)

Summary: No previous studies have documented changes in salivary secretion in patients with malaria. This study aimed to compare salivary secretion and composition in malaria positive and malaria negative individuals. Ninety participants composed of 40 malaria parasite positive and 50 malaria parasite negative ...

Pre-clinical and clinical development of the first placental malaria vaccine

DEFF Research Database (Denmark)

Pehrson, Caroline; Salanti, Ali; Theander, Thor G

2017-01-01

the condition.  Areas covered: Pub Med was searched using the broad terms 'malaria parasite placenta' to identify studies of interactions between parasite and host, 'prevention of placental malaria' to identify current strategies to prevent placental malaria, and 'placental malaria vaccine' to identify pre-clinical...... vaccine development. However, all papers from these searches were not systematically included.  Expert commentary: The first phase I clinical trials of vaccines are well underway. Trials testing efficacy are more complicated to carry out as only women that are exposed to parasites during pregnancy...

Chemical effects and their consequences for individuals occupationally exposed to ionizing radiation

International Nuclear Information System (INIS)

Salvador, C.; Kahl, G.G.; Kühn, P.; Zottis, A.D.; Flôr, R.C.

2017-01-01

By legal determination, workers exposed to ionizing radiation should use individual dosimeters in the most exposed region of the body, designed to estimate the effective dose, as well as radiation protective clothing to minimize occupational exposures. Regarding dosimetry, in most cases it is perceived that the monthly values of exposure are within the limits of normality, however, even being below the limit can not rule out the possibility of damage that the low dose of ionizing radiation can cause. The objective of this article is to highlight the main chemical effects caused by exposure to ionizing radiation, especially biochemical damage in DNA, chromosomal aberrations and the correlation with the exposure of occupationally exposed individuals, as well as individuals from the public. A bibliographic search was carried out in indexed databases from February to April 2017 with the following descriptors: Radiation Ionizing, DNA Damage and Occupational Exposure. In the 'Science Direct' database were found 1205 articles, in the 'Scopus' 19 articles, in the 'Web of Science' 83 articles, in the 'PubMed' 22 articles and in the 'VHL' 60 articles related to the theme. It was concluded that exposure to ionizing radiation can affect the DNA molecule despite its repair mechanisms, which may result in genotoxicity. It has been reported a correlation between occupationally exposed individuals and chromosomal aberrations, demonstrating that even low doses of ionizing radiation can compromise the genetic material integrity of exposed workers, leading to the need for a periodic cytogenetic study for this group of workers

Individual doses' register of occupationally exposed persons in the Republic of Moldova

International Nuclear Information System (INIS)

Hustuc, A.; Chiruta, Iu.

2009-01-01

The storage and processing of the data acquired through different monitoring techniques are of vital importance for controlling the individual doses of the occupationally exposed workers facilitating the determination of exposure pathway and furthering the policy of radiological protection. The use of the data bases for the evidence of the individual doses of the occupationally exposed workers to the ionizing radiation is useful in studies of risks and potential exposure, and in future epidemiological studies. (authors)

Fitness consequences of larval exposure to Beauveria bassiana on adults of the malaria vector Anopheles stephensi.

Science.gov (United States)

Vogels, Chantal B F; Bukhari, Tullu; Koenraadt, Constantianus J M

2014-06-01

Entomopathogenic fungi have shown to be effective in biological control of both larval and adult stages of malaria mosquitoes. However, a small fraction of mosquitoes is still able to emerge after treatment with fungus during the larval stage. It remains unclear whether fitness of these adults is affected by the treatment during the larval stage and whether they are still susceptible for another treatment during the adult stage. Therefore, we tested the effects of larval exposure to the entomopathogenic fungus Beauveria bassiana on fitness of surviving Anopheles stephensi females. Furthermore, we tested whether larval exposed females were still susceptible to re-exposure to the fungus during the adult stage. Sex ratio, survival and reproductive success were compared between non-exposed and larval exposed A. stephensi. Comparisons were also made between survival of non-exposed and larval exposed females that were re-exposed to B. bassiana during the adult stage. Larval treatment did not affect sex ratio of emerging mosquitoes. Larval exposed females that were infected died significantly faster and laid equal numbers of eggs from which equal numbers of larvae hatched, compared to non-exposed females. Larval exposed females that were uninfected had equal survival, but laid a significantly larger number of eggs from which a significantly higher number of larvae hatched, compared to non-exposed females. Larval exposed females which were re-exposed to B. bassiana during the adult stage had equal survival as females exposed only during the adult stage. Our results suggest that individual consequences for fitness of larval exposed females depended on whether a fungal infection was acquired during the larval stage. Larval exposed females remained susceptible to re-exposure with B. bassiana during the adult stage, indicating that larval and adult control of malaria mosquitoes with EF are compatible. Copyright © 2014. Published by Elsevier Inc.

Heritability of malaria in Africa.

Directory of Open Access Journals (Sweden)

Margaret J Mackinnon

2005-12-01

Full Text Available While many individual genes have been identified that confer protection against malaria, the overall impact of host genetics on malarial risk remains unknown.We have used pedigree-based genetic variance component analysis to determine the relative contributions of genetic and other factors to the variability in incidence of malaria and other infectious diseases in two cohorts of children living on the coast of Kenya. In the first, we monitored the incidence of mild clinical malaria and other febrile diseases through active surveillance of 640 children 10 y old or younger, living in 77 different households for an average of 2.7 y. In the second, we recorded hospital admissions with malaria and other infectious diseases in a birth cohort of 2,914 children for an average of 4.1 y. Mean annual incidence rates for mild and hospital-admitted malaria were 1.6 and 0.054 episodes per person per year, respectively. Twenty-four percent and 25% of the total variation in these outcomes was explained by additively acting host genes, and household explained a further 29% and 14%, respectively. The haemoglobin S gene explained only 2% of the total variation. For nonmalarial infections, additive genetics explained 39% and 13% of the variability in fevers and hospital-admitted infections, while household explained a further 9% and 30%, respectively.Genetic and unidentified household factors each accounted for around one quarter of the total variability in malaria incidence in our study population. The genetic effect was well beyond that explained by the anticipated effects of the haemoglobinopathies alone, suggesting the existence of many protective genes, each individually resulting in small population effects. While studying these genes may well provide insights into pathogenesis and resistance in human malaria, identifying and tackling the household effects must be the more efficient route to reducing the burden of disease in malaria-endemic areas.

Towards A Malaria Vaccine?

Directory of Open Access Journals (Sweden)

B S GARG

1990-12-01

Full Text Available The last few years have seen a marked change in the understanding of malaria mmunology.We have very little knowledge on immunity of Malaria based on experiments in humanbeings due to ethical reasons. Whatsoever our knowledge exists at present is based onexperimentas in mice and monkey. However it is clear that it is sporzoite or merozoitewhich is directly exposed to our immune system in the life cycle of Malaria parasite. On thebasis of human experiments we can draw inference that immunity to malaria is species.specific (on cross immunity, stage specific and strain specific as well acquired in the response to surface antigen and relapsed antigen although the parasite also demonstrates escape machanism to immune system.So the host system kills or elimi nate the parasite by means of (a Antbody to extracell~ular form of parasite with the help of mechanism of Block invasion, Agglutination or opsonization and/or (b Cellular machanism-either by phago-cytosis of parasite or by antibody dependent cellular cytotoxicity ABCC (? or by effects of mediators like tumor necrosis fJ.ctor (TNF in cerebaral malaria or crisis forming factor as found in sudan or by possible role of lysis mechanism.However, inspite of all these theories the parasite has been able to invade the immunesystem by virtue of its intracellular development stage specificity, sequestration in capillaries and also by its unusual characteristics of antigenic diversity and antigenic variation.

Analysing malaria drug trials on a per-individual or per-clone basis: a comparison of methods.

Science.gov (United States)

Jaki, Thomas; Parry, Alice; Winter, Katherine; Hastings, Ian

2013-07-30

There are a variety of methods used to estimate the effectiveness of antimalarial drugs in clinical trials, invariably on a per-person basis. A person, however, may have more than one malaria infection present at the time of treatment. We evaluate currently used methods for analysing malaria trials on a per-individual basis and introduce a novel method to estimate the cure rate on a per-infection (clone) basis. We used simulated and real data to highlight the differences of the various methods. We give special attention to classifying outcomes as cured, recrudescent (infections that never fully cleared) or ambiguous on the basis of genetic markers at three loci. To estimate cure rates on a per-clone basis, we used the genetic information within an individual before treatment to determine the number of clones present. We used the genetic information obtained at the time of treatment failure to classify clones as recrudescence or new infections. On the per-individual level, we find that the most accurate methods of classification label an individual as newly infected if all alleles are different at the beginning and at the time of failure and as a recrudescence if all or some alleles were the same. The most appropriate analysis method is survival analysis or alternatively for complete data/per-protocol analysis a proportion estimate that treats new infections as successes. We show that the analysis of drug effectiveness on a per-clone basis estimates the cure rate accurately and allows more detailed evaluation of the performance of the treatment. Copyright © 2012 John Wiley & Sons, Ltd.

Individual radiological monitoring for exposed personnel of Nuclear Fuel Plant at Pitesti

International Nuclear Information System (INIS)

Ivana, T.; Epure, Gh.

2010-01-01

In the activity of nuclear fuel fabrication of CANDU type, based on natural and depleted uranium, individual radiological monitoring of the personnel exposed to ionizing radiation is very carefully approached. For Nuclear Fuel Plant (NFP) facility, where uranium appears in bulk and itemized form, measures for individual radiological monitoring are established by Radiological Safety Manual (MSR) in accordance with national and international legislation. All NFP employees are classified in either category A or category B of exposure to ionizing radiation. The classification is a function of type of activity and magnitude of exposure. All the exposed personnel are monitored for external doses (from gamma radiation) by measuring the equivalent dose H p (10) with monthly frequency. The system used for external individual dosimetric monitoring is based on the thermoluminescent dosimeter (TLD) of PANASONIC type UD813AS14. The NFP incorporates an in-house dosimetric laboratory notified by Romanian regulatory body CNCAN (National Commission for Control of Nuclear Activities). The workers handling nuclear materials are exposed to internal intake of uranium, mainly by inhalation. For internal doses monitoring is included part of exposed employees working directly with radioactive open sources (pulverulent or liquid nuclear materials), UO 2 sinterable powder, green pellets, sintered pellets, scrap and radioactive effluents. The estimation of internal exposure is made quarterly using the results from radioactive airborne monitors operating in the working places. The internal dose of each person exposed to open sources is calculated taking into account the rate of breathing, the time spent at the work place and the dose-activity coefficient (variable function of uranium absorption rate). The total effective individual dose is obtained by summing the external dose and internal dose (E=E ext +E int ). For conformity, the total effective individual dose (E) is compared with dose

Optimal price subsidies for appropriate malaria testing and treatment behaviour

DEFF Research Database (Denmark)

Hansen, K. S.; Lesner, T. H.; Østerdal, L. P.

2016-01-01

Background: Malaria continues to be a serious public health problem particularly in Africa. Many people infected with malaria do not access effective treatment due to high price. At the same time many individuals receiving malaria drugs do not suffer from malaria because of the common practice of...... seeking care for malaria in the private sector. © 2016 The Author(s)....

Individual-level factors associated with the risk of acquiring human Plasmodium knowlesi malaria in Malaysia: a case-control study.

Science.gov (United States)

Grigg, Matthew J; Cox, Jonathan; William, Timothy; Jelip, Jenarun; Fornace, Kimberly M; Brock, Patrick M; von Seidlein, Lorenz; Barber, Bridget E; Anstey, Nicholas M; Yeo, Tsin W; Drakeley, Christopher J

2017-06-09

The emergence of human malaria due to the monkey parasite Plasmodium knowlesi threatens elimination efforts in southeast Asia. Changes in land use are thought to be driving the rise in reported P knowlesi cases, but the role of individual-level factors is unclear. To address this knowledge gap we assessed human and environmental factors associated with zoonotic knowlesi malaria risk. We did this population-based case-control study over a 2 year period in the state of Sabah in Malaysia. We enrolled cases with microscopy-positive, PCR-confirmed malaria who presented to two primary referral hospitals serving the adjacent districts of Kudat and Kota Marudu. We randomly selected three malaria-negative community controls per case, who were matched by village within 2 weeks of case detection. We obtained questionnaire data on demographics, behaviour, and residential malaria risk factors, and we also assessed glucose-6-phosphate dehydrogenase (G6PD) enzyme activity. We used conditional logistic regression models to evaluate exposure risk between P knowlesi cases and controls, and between P knowlesi and human-only Plasmodium spp malaria cases. From Dec 5, 2012, to Jan 30, 2015, we screened 414 patients and subsequently enrolled 229 cases with P knowlesi malaria mono-infection and 91 cases with other Plasmodium spp infection. We enrolled 953 matched controls, including 683 matched to P knowlesi cases and 270 matched to non- P knowlesi cases. Age 15 years or older (adjusted odds ratio [aOR] 4·16, 95% CI 2·09-8·29, pwork (3·50, CI, 1·34-9·15, p=0·011), sleeping outside (3·61, 1·48-8·85, p=0·0049), travel (2·48, 1·45-4·23, p=0·0010), being aware of the presence of monkeys in the past 4 weeks (3·35, 1·91-5·88, pworking in agricultural areas were at highest risk of knowlesi malaria, although peri-domestic transmission also occurrs. Human behavioural factors associated with P knowlesi transmission could be targeted in future public health interventions. United

Linking sub-individual and supra-individual effects in Daphnia magna exposed to sub-lethal concentration of chlorpyrifos.

Science.gov (United States)

Ferrario, Claudia; Parolini, Marco; De Felice, Beatrice; Villa, Sara; Finizio, Antonio

2018-04-01

The main objective of the present study was to investigate possible links between sub-individual and supra-individual levels (i.e. population level) biomarkers in D. magna exposed to sublethal concentrations of the insecticide chlorpyrifos (CPF). To achieve the aim, 8-day old individuals were exposed for 96 h to two environmentally relevant concentrations of CPF (50 and 250 ng/L). Sub-individual level effects were investigated by measuring the activity of antioxidant (SOD, CAT, and GPx) and detoxifying (GST) enzymes, as well as by measuring the acetylcholinesterase (AChE) inhibition. In addition, the effects at supra-individual level were assessed by using a video-tracking system and analyzing changes in swimming capabilities (i.e. percentage of activity time, distance moved, and velocity). Our data have shown that daphnids exposed to both CPF concentrations were in a condition of stress which was highlighted by changes in both sub- and supra-individual biomarkers. Moreover, our results highlighted that the lowest tested CPF concentration did not modulate the antioxidant and detoxifying enzymes, whereas, an inhibition of AChE and a decrease of some parameters related to swimming behaviour (distance moved and velocity) were noted. On the contrary, significant changes in all the sub-individual biomarkers were measured at the highest tested concentration. In addition, organisms recovered the movement capability (distance moved) and also activate a mechanism of avoidance (increased swimming velocity). On the other hand, a reduction in the percent of active time was measured and this was attributed to the energy spent by organisms to activate antioxidant and detoxifying enzymes and the mechanism of avoidance. Based on these results, our study suggests the existence of a link between sub- and supra-individual levels, as the activation or non-activation in the antioxidant and detoxifying enzymes activities can led to different modifications of the swimming behaviour

Burden of asymptomatic malaria among a tribal population in a forested village of central India: a hidden challenge for malaria control in India.

Science.gov (United States)

Chourasia, M K; Raghavendra, K; Bhatt, R M; Swain, D K; Valecha, N; Kleinschmidt, I

2017-06-01

Chhattisgarh in India is a malaria-endemic state with seven southern districts that contributes approximately 50-60% of the reported malaria cases in the state every year. The problem is further complicated due to asymptomatic malaria cases which are largely responsible for persistent transmission. This study was undertaken in one of the forested villages of the Keshkal subdistrict in Kondagaon district to ascertain the proportion of the population harbouring subclinical malarial infections. Community-based cross-sectional study. Mass blood surveys were undertaken of the entire population of the village in the post-monsoon seasons of 2013 and 2014. Fingerprick blood smears were prepared from individuals of all ages to detect malaria infections in their blood. Individuals with fever at the time of the survey were tested with rapid diagnostic tests, and parasitaemia in thick blood smears was confirmed by microscopy. Malaria-positive cases were treated with anti-malarials in accordance with the national drug policy. Peripheral blood smears of 134 and 159 individuals, including children, were screened for malaria infection in 2013 and 2014, respectively. Overall, the malaria slide positivity rates were 27.6% and 27.7% in 2013 and 2014, respectively, and the prevalence rates of asymptomatic malaria were 20% and 22.8%. This study showed that, for two consecutive years, the prevalence of asymptomatic malaria infection was significantly higher among children aged ≤14 years (34.4% and 34.1% for 2013 and 2014, respectively) compared with adults (15.2% and 18.2% for 2013 and 2014, respectively; P = 0.023 and 0.04, respectively). The number of asymptomatic malaria cases, especially Plasmodium falciparum, is significant, reinforcing the underlying challenge facing the malaria elimination programme in India. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Is outdoor vector control needed for malaria elimination? An individual-based modelling study.

Science.gov (United States)

Zhu, Lin; Müller, Günter C; Marshall, John M; Arheart, Kristopher L; Qualls, Whitney A; Hlaing, WayWay M; Schlein, Yosef; Traore, Sekou F; Doumbia, Seydou; Beier, John C

2017-07-03

Residual malaria transmission has been reported in many areas even with adequate indoor vector control coverage, such as long-lasting insecticidal nets (LLINs). The increased insecticide resistance in Anopheles mosquitoes has resulted in reduced efficacy of the widely used indoor tools and has been linked with an increase in outdoor malaria transmission. There are considerations of incorporating outdoor interventions into integrated vector management (IVM) to achieve malaria elimination; however, more information on the combination of tools for effective control is needed to determine their utilization. A spatial individual-based model was modified to simulate the environment and malaria transmission activities in a hypothetical, isolated African village setting. LLINs and outdoor attractive toxic sugar bait (ATSB) stations were used as examples of indoor and outdoor interventions, respectively. Different interventions and lengths of efficacy periods were tested. Simulations continued for 420 days, and each simulation scenario was repeated 50 times. Mosquito populations, entomologic inoculation rates (EIRs), probabilities of local mosquito extinction, and proportion of time when the annual EIR was reduced below one were compared between different intervention types and efficacy periods. In the village setting with clustered houses, the combinational intervention of 50% LLINs plus outdoor ATSBs significantly reduced mosquito population and EIR in short term, increased the probability of local mosquito extinction, and increased the time when annual EIR is less than one per person compared to 50% LLINs alone; outdoor ATSBs alone significantly reduced mosquito population in short term, increased the probability of mosquito extinction, and increased the time when annual EIR is less than one compared to 50% LLINs alone, but there was no significant difference in EIR in short term between 50% LLINs and outdoor ATSBs. In the village setting with dispersed houses, the

Bioinformatics approaches to malaria

DEFF Research Database (Denmark)

Hansen, Daniel Aaen

Malaria is a life threatening disease found in tropical and subtropical regions of the world. Each year it kills 781 000 individuals; most of them are children under the age of five in sub-Saharan Africa. The most severe form of malaria in humans is caused by the parasite Plasmodium falciparum......, which is the subject of the first part of this thesis. The PfEMP1 protein which is encoded by the highly variablevargene family is important in the pathogenesis and immune evasion of malaria parasites. We analyzed and classified these genes based on the upstream sequence in seven......Plasmodium falciparumclones. We show that the amount of nucleotide diversity is just as big within each clone as it is between the clones. DNA methylation is an important epigenetic mark in many eukaryotic species. We are studying DNA methylation in the malaria parasitePlasmodium falciparum. The work is still in progress...

Personality and psychopathological profiles in individuals exposed to mobbing.

Science.gov (United States)

Girardi, Paolo; Monaco, Edoardo; Prestigiacomo, Claudio; Talamo, Alessandra; Ruberto, Amedeo; Tatarelli, Roberto

2007-01-01

Increasingly, mental health and medical professionals have been asked to assess claims of psychological harm arising from harassment at the workplace, or "mobbing." This study assessed the personality and psychopathological profiles of 146 individuals exposed to mobbing using validity, clinical, and content scales of the Minnesota Multiphasic Personality Inventory 2. Profiles and factor analyses were obtained. Two major dimensions emerged among those exposed to mobbing: (a) depressed mood, difficulty in making decisions, change-related anguish, and passive-aggressive traits (b) somatic symptoms, and need for attention and affection. This cross-sectional pilot study provides evidence that personality profiles of mobbing victims and psychological damage resulting from mobbing may be evaluated using standardized assessments, though a longitudinal study is needed to delineate cause-and-effect relationships.

Nanomimics of host cell membranes block invasion and expose invasive malaria parasites.

Science.gov (United States)

Najer, Adrian; Wu, Dalin; Bieri, Andrej; Brand, Françoise; Palivan, Cornelia G; Beck, Hans-Peter; Meier, Wolfgang

2014-12-23

The fight against most infectious diseases, including malaria, is often hampered by the emergence of drug resistance and lack or limited efficacies of vaccines. Therefore, new drugs, vaccines, or other strategies to control these diseases are needed. Here, we present an innovative nanotechnological strategy in which the nanostructure itself represents the active substance with no necessity to release compounds to attain therapeutic effect and which might act in a drug- and vaccine-like dual function. Invasion of Plasmodium falciparum parasites into red blood cells was selected as a biological model for the initial validation of this approach. Stable nanomimics-polymersomes presenting receptors required for parasite attachment to host cells-were designed to efficiently interrupt the life cycle of the parasite by inhibiting invasion. A simple way to build nanomimics without postformation modifications was established. First, a block copolymer of the receptor with a hydrophobic polymer was synthesized and then mixed with a polymersome-forming block copolymer. The resulting nanomimics bound parasite-derived ligands involved in the initial attachment to host cells and they efficiently blocked reinvasion of malaria parasites after their egress from host cells in vitro. They exhibited efficacies of more than 2 orders of magnitude higher than the soluble form of the receptor, which can be explained by multivalent interactions of several receptors on one nanomimic with multiple ligands on the infective parasite. In the future, our strategy might offer interesting treatment options for severe malaria or a way to modulate the immune response.

Heritability of Malaria in Africa.

Directory of Open Access Journals (Sweden)

2005-11-01

Full Text Available BACKGROUND: While many individual genes have been identified that confer protection against malaria, the overall impact of host genetics on malarial risk remains unknown. METHODS AND FINDINGS: We have used pedigree-based genetic variance component analysis to determine the relative contributions of genetic and other factors to the variability in incidence of malaria and other infectious diseases in two cohorts of children living on the coast of Kenya. In the first, we monitored the incidence of mild clinical malaria and other febrile diseases through active surveillance of 640 children 10 y old or younger, living in 77 different households for an average of 2.7 y. In the second, we recorded hospital admissions with malaria and other infectious diseases in a birth cohort of 2,914 children for an average of 4.1 y. Mean annual incidence rates for mild and hospital-admitted malaria were 1.6 and 0.054 episodes per person per year, respectively. Twenty-four percent and 25% of the total variation in these outcomes was explained by additively acting host genes, and household explained a further 29% and 14%, respectively. The haemoglobin S gene explained only 2% of the total variation. For nonmalarial infections, additive genetics explained 39% and 13% of the variability in fevers and hospital-admitted infections, while household explained a further 9% and 30%, respectively. CONCLUSION: Genetic and unidentified household factors each accounted for around one quarter of the total variability in malaria incidence in our study population. The genetic effect was well beyond that explained by the anticipated effects of the haemoglobinopathies alone, suggesting the existence of many protective genes, each individually resulting in small population effects. While studying these genes may well provide insights into pathogenesis and resistance in human malaria, identifying and tackling the household effects must be the more efficient route to reducing the burden

Association of haptoglobin phenotypes with susceptibility to Falciparum Malaria in Sudan

International Nuclear Information System (INIS)

Elagib, Atif Abdel Rahman

1999-09-01

The predisposing factors for the development of serious and diverse complications caused by falciparum are not very well understood. The search for host molecular markers which the disease presentation and prognosis, is an important issue in malaria research. Along this time line, the haptoglobin phenotype of Sudanese individuals infected with falciparum malaria both complicated and non-complicated, and non-infected controls, from randomly selected individuals were determined. Anti-human Haptoglobin antibodies was radiolabelled with 125 I , using chloramine T-method.Haptoglobin phenotype determination was performed by electrophoresis separation of sera on polyacrylamide gel followed by benzidine staining, which was shown to be time and material saving, and as sensitive as Western blotting. The distribution of the haptoglobin (1-1), (2-1) among 273 uncomplicated falicparm malaria patients, was found to be 60.8%, 29.2% and 6.9%, respectively. The distribution among 208 randomly selected individuals infected with falciparm malaria both controls, from randomly selected individuals were determined. Hyptogolobin phenotype was performed by electrophoresis separation of sera on polyacrylamide gel followed by benzidine staining, which was shown to be time and material saving, and as sensitive as Western blotting. The distribution of the haptoglobin phenotypes (1-1), (2-1) and (2-2) among 273 uncomplicated facilparum malaria patients, was found to be 60.8 % , 29.7 % and 6.9 %, respectively. The distribution among 208 randomly selected healthy controls was 26.0 %, 55.8 % and 18.3 % respectively . The results show that the number of individuals with haptoglobin phentype (1-1) is significantly higher among patients with falcilparum malaria (complicated and complicated) when compared to the controls. However, the controls showed a normal distribution of the phenotypes comparable to available data obtained from similar African populations. Consequently, we suggest that the

Cross-sectional analysis of the association between bedtime and malaria exposure in the Ouest and Sud-Est Departments of Haiti.

Science.gov (United States)

Stephenson, Caroline J; Rossheim, Matthew E; Frankenfeld, Cara L; Boncy, Jacques; Okech, Bernard A; von Fricken, Michael E

2017-12-01

The governments of Haiti and the Dominican Republic have a binational agreement to work towards malaria elimination for the island of Hispaniola by the year 2020. Understanding malaria-related knowledge and behaviors can help inform elimination efforts. This study examined the association between social-behavioral factors, like bedtime and bed net ownership, with malaria seroconversion status among people in the Ouest and Sud-Est departments of Haiti. In 2013, cross-sectional survey data (n=377) and blood samples were collected from a convenience sample of individuals within community, clinic and school settings. Logistic regression models were constructed to examine associations between social-behavioral factors and malaria exposure, adjusting for potential confounders. Compared to people going to bed between 6 and 8 pm, those going to bed between 8 and 10 pm were 2.67 (OR, 95% CI: 1.16-6.14) times as likely to have been exposed to malaria. Participants who reported going to bed after 10 pm were 5.96 times as likely to have had previous malaria exposure (OR, 95% CI: 2.26-15.7), compared to 6-8 pm. No significant associations were found between malaria exposure and either insecticide use nor bed net ownership. These findings are consistent with suspected feeding behaviors of Anopheles albimanus, which prefers feeding at night and outdoors. Study findings may improve overall understanding of malaria transmission in Haiti and potentially guide future studies conducted in this region. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment Of Renal Function In Malaria Patients In Minna, North ...

African Journals Online (AJOL)

Data obtained were analyzed using one-way analysis of variance to compare variation among malaria patients and individuals without malaria, Duncan multiple range test to compare variation among means, and correlation matrix to evaluate correlation between the parameters measured. Proteinuria in malaria cases ...

Modelling homogeneous regions of social vulnerability to malaria in Rwanda.

Science.gov (United States)

Bizimana, Jean Pierre; Kienberger, Stefan; Hagenlocher, Michael; Twarabamenye, Emmanuel

2016-03-31

Despite the decline in malaria incidence due to intense interventions, potentials for malaria transmission persist in Rwanda. To eradicate malaria in Rwanda, strategies need to expand beyond approaches that focus solely on malaria epidemiology and also consider the socioeconomic, demographic and biological/disease-related factors that determine the vulnerability of potentially exposed populations. This paper analyses current levels of social vulnerability to malaria in Rwanda by integrating a set of weighted vulnerability indicators. The paper uses regionalisation techniques as a spatially explicit approach for delineating homogeneous regions of social vulnerability to malaria. This overcomes the limitations of administrative boundaries for modelling the trans-boundary social vulnerability to malaria. The utilised approach revealed high levels of social vulnerability to malaria in the highland areas of Rwanda, as well as in remote areas where populations are more susceptible. Susceptibility may be due to the populations' lacking the capacity to anticipate mosquito bites, or lacking resilience to cope with or recover from malaria infection. By highlighting the most influential indicators of social vulnerability to malaria, the applied approach indicates which vulnerability domains need to be addressed, and where appropriate interventions are most required. Interventions to improve the socioeconomic development in highly vulnerable areas could prove highly effective, and provide sustainable outcomes against malaria in Rwanda. This would ultimately increase the resilience of the population and their capacity to better anticipate, cope with, and recover from possible infection.

Bio-dosimetry for radiation-exposed individuals

International Nuclear Information System (INIS)

Sauvaigo, Sylvie; Chapuis, Violaine; Caillat, Sylvain; Sarrazy, Fanny; Breton, Jean

2013-01-01

Exposure of civil populations to genotoxic chemicals or radioactive hazard is an increased concern. It is not only an industrial risk (chemistry plant accident for example) but also a national security problem due to the threat of radiological and nuclear terrorism. It is important to anticipate the need of a bio-dosimetry tool aimed at identifying exposed population in the absence of acute syndrome, in order to assure the medical care that would prevent carcinogenic consequences. DNA repair is a bio-marker of exposure to geno-toxics in individuals. A DNA repair signature can be assessed from Peripheral Blood Mononuclear Cells (PBMCs) that reflects the exposure history of the individuals, using a functional enzymatic assay on bio-chip. A proof of concept was obtained using PBMCs from patients undergoing radiotherapy regimen. We identified two classes of responses among patients, if we except a very atypical signature in one patient that could reflect defects in DNA repair. Interestingly, repair of the major oxidative lesions increased during the course of the radiotherapy. We propose to implement this fast, quantitative, possibly automatized assay to identify bio-markers of exposure to geno-toxics and to validate the exposure bio-markers through ex vivo exposure of blood from volunteers. (authors)

Renewed mobilization against malaria.

Science.gov (United States)

1991-01-01

1 million people die in the world from malaria annually, 800,000 of whom are 5 year old children in Sub-Sahara Africa. Further it affects 270 million people. In fact, 110 million develop malaria, 90 million of whom are from Sub-Saharan Africa. Thus WHO has introduced a new world initiative for malaria control to reverse the worsening trend that began in the mid 1970s. In October 1991, 150 officials from 50 African, Asian, and Latin American countries and participants from UN cooperation and development agencies and bilateral agencies attended an interregional conference at the WHO Regional office for Africa in Brazzaville, Congo. It strove to evaluate malaria situations specific to Africa, to update the malaria control plan in Africa, and to contribute to the development of an implementable world strategy. This world strategy needs to consider the local situation and encourage participation of the government and people of affected countries. Further individuals, communities, and various sectors of the national economy including those involved in health, education, development, and agriculture need to participate in malaria control. In addition, for this strategy to work, most countries must strengthen the management and financing of health services to meet their needs. For example, local populations must share local operating costs such as those for essential drugs and mosquito control operations. Community participation must also include personal protection such as impregnated bed nets and environmental measures. Besides malaria control must be integrated into the existing health system at country, provincial, and peripheral levels. In sum, improved case management, control of malaria transmission, and prevention and control of epidemics form the basis for the new strategy.

Artemether-Lumefantrine Combination Therapy for Treatment of Uncomplicated Malaria: The Potential for Complex Interactions with Antiretroviral Drugs in HIV-Infected Individuals

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Pauline Byakika-Kibwika

2011-01-01

Full Text Available Treatment of malaria in HIV-infected individuals receiving antiretroviral therapy (ART poses significant challenges. Artemether-lumefantrine (AL is one of the artemisisnin-based combination therapies recommended for treatment of malaria. The drug combination is highly efficacious against sensitive and multidrug resistant falciparum malaria. Both artemether and lumefantrine are metabolized by hepatic cytochrome P450 (CYP450 enzymes which metabolize the protease inhibitors (PIs and nonnucleoside reverse transcriptase inhibitors (NNRTIs used for HIV treatment. Coadministration of NNRTIs and PIs with AL could potentially cause complex pharmacokinetic drug interactions. NNRTI by inducing CYP450 3A4 enzyme and PIs by inhibiting CYP450 3A4 enzymes could influence both artemether and lumefantrine concentrations and their active metabolites dihydroartemisinin and desbutyl-lumefantrine, predisposing patients to poor treatment response, toxicity, and risk for development of resistance. There are scanty data on these interactions and their consequences. Pharmacokinetic studies to evaluate these interactions in the target populations are urgently needed.

Relative Susceptibilities of ABO Blood Groups to Plasmodium falciparum Malaria in Ghana.

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Afoakwah, Richmond; Aubyn, Edmond; Prah, James; Nwaefuna, Ekene Kwabena; Boampong, Johnson N

2016-01-01

The clinical outcome of falciparum malaria in endemic areas is influenced by erythrocyte polymorphisms including the ABO blood groups. Studies have reported association of ABO blood group to resistance, susceptibility, and severity of P. falciparum malaria infection. Individuals with blood group "A" have been found to be highly susceptible to falciparum malaria whereas blood group "O" is said to confer protection against complicated cases. We analyzed samples from 293 young children less than six years old with malaria in the Korle-Bu Teaching Hospital in Accra, Ghana. It was observed that group O was present in about 16.1% of complicated cases weighed against 40.9% of uncomplicated controls. Individuals with complicated malaria were about twice likely to be of blood groups A and B compared to group O (A versus O, OR = 1.90, 95% CI = 1.59-2.26, P Blood group O participants with complicated diseases had low parasitaemia compared to the other blood groups (P blood group O individuals a survival advantage over the other groups in complicated malaria as suggested. Participants with complicated falciparum malaria were generally anaemic and younger than those with uncomplicated disease.

Asymptomatic infection in individuals from the municipality of Barcelos (Brazilian Amazon is not associated with the anti-Plasmodium falciparum glycosylphosphatidylinositol antibody response

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Larissa Rodrigues Gomes

2013-09-01

Full Text Available Anti-glycosylphosphatidylinositol (GPI antibodies (Abs may reflect and mediate, at least partially, anti-disease immunity in malaria by neutralising the toxic effect of parasitic GPI. Thus, we assessed the anti-GPI Ab response in asymptomatic individuals living in an area of the Brazilian Amazon that has a high level of malaria transmission. For comparative purposes, we also investigated the Ab response to a crude extract prepared from Plasmodium falciparum, the merozoite surface protein (MSP3 antigen of P. falciparum and the MSP 1 antigen of Plasmodium vivax (PvMSP1-19 in these individuals and in Angolan patients with acute malaria. Our data suggest that the Ab response against P. falciparum GPI is not associated with P. falciparum asymptomatic infection in individuals who have been chronically exposed to malaria in the Brazilian Amazon. However, this Ab response could be related to ongoing parasitaemia (as was previously shown in the Angolan patients. In addition, our data show that PvMSP1-19may be a good marker antigen to reflect previous exposure to Plasmodium in areas that have a high transmission rate of P. vivax.

Human T cell recognition of the blood stage antigen Plasmodium hypoxanthine guanine xanthine phosphoribosyl transferase (HGXPRT in acute malaria

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Woodberry Tonia

2009-06-01

Full Text Available Abstract Background The Plasmodium purine salvage enzyme, hypoxanthine guanine xanthine phosphoribosyl transferase (HGXPRT can protect mice against Plasmodium yoelii pRBC challenge in a T cell-dependent manner and has, therefore, been proposed as a novel vaccine candidate. It is not known whether natural exposure to Plasmodium falciparum stimulates HGXPRT T cell reactivity in humans. Methods PBMC and plasma collected from malaria-exposed Indonesians during infection and 7–28 days after anti-malarial therapy, were assessed for HGXPRT recognition using CFSE proliferation, IFNγ ELISPOT assay and ELISA. Results HGXPRT-specific T cell proliferation was found in 44% of patients during acute infection; in 80% of responders both CD4+ and CD8+ T cell subsets proliferated. Antigen-specific T cell proliferation was largely lost within 28 days of parasite clearance. HGXPRT-specific IFN-γ production was more frequent 28 days after treatment than during acute infection. HGXPRT-specific plasma IgG was undetectable even in individuals exposed to malaria for at least two years. Conclusion The prevalence of acute proliferative and convalescent IFNγ responses to HGXPRT demonstrates cellular immunogenicity in humans. Further studies to determine minimal HGXPRT epitopes, the specificity of responses for Plasmodia and associations with protection are required. Frequent and robust T cell proliferation, high sequence conservation among Plasmodium species and absent IgG responses distinguish HGXPRT from other malaria antigens.

Malaria-induced changes in host odors enhance mosquito attraction.

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De Moraes, Consuelo M; Stanczyk, Nina M; Betz, Heike S; Pulido, Hannier; Sim, Derek G; Read, Andrew F; Mescher, Mark C

2014-07-29

Vector-borne pathogens may alter traits of their primary hosts in ways that influence the frequency and nature of interactions between hosts and vectors. Previous work has reported enhanced mosquito attraction to host organisms infected with malaria parasites but did not address the mechanisms underlying such effects. Here we document malaria-induced changes in the odor profiles of infected mice (relative to healthy individuals) over the course of infection, as well as effects on the attractiveness of infected hosts to mosquito vectors. We observed enhanced mosquito attraction to infected mice during a key period after the subsidence of acute malaria symptoms, but during which mice remained highly infectious. This attraction corresponded to an overall elevation in the volatile emissions of infected mice observed during this period. Furthermore, data analyses--using discriminant analysis of principal components and random forest approaches--revealed clear differences in the composition of the volatile blends of infected and healthy individuals. Experimental manipulation of individual compounds that exhibited altered emission levels during the period when differential vector attraction was observed also elicited enhanced mosquito attraction, indicating that compounds being influenced by malaria infection status also mediate vector host-seeking behavior. These findings provide important insights into the cues that mediate vector attraction to hosts infected with transmissible stages of malaria parasites, as well as documenting characteristic changes in the odors of infected individuals that may have potential value as diagnostic biomarkers of infection.

Chronic Plasmodium falciparum infections in an area of low intensity malaria transmission in the Sudan

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Hamad, A A; El Hassan, I M; El Khalifa, A A

2000-01-01

Chronic Plasmodium falciparum malaria infections in a Sudanese village, in an area of seasonal and unstable malaria transmission, were monitored and genetically characterized to study the influence of persistent infection on the immunology and epidemiology of low endemicity malaria. During...... the October-December malaria season of 1996, 51 individuals out of a population of 420 had confirmed and treated P. falciparum malaria in the village of Daraweesh in eastern Sudan. In a cross-sectional survey carried out in December 1996, an additional 6 individuals were found to harbour a microscopically...

Characteristics of Travel-Related Severe Plasmodium vivax and Plasmodium falciparum Malaria in Individuals Hospitalized at a Tertiary Referral Center in Lima, Peru.

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Llanos-Chea, Fiorella; Martínez, Dalila; Rosas, Angel; Samalvides, Frine; Vinetz, Joseph M; Llanos-Cuentas, Alejandro

2015-12-01

Severe Plasmodium falciparum malaria is uncommon in South America. Lima, Peru, while not endemic for malaria, is home to specialized centers for infectious diseases that admit and manage patients with severe malaria (SM), all of whom contracted infection during travel. This retrospective study describes severe travel-related malaria in individuals admitted to one tertiary care referral hospital in Lima, Peru; severity was classified based on criteria published by the World Health Organization in 2000. Data were abstracted from medical records of patients with SM admitted to Hospital Nacional Cayetano Heredia from 2006 to 2011. Of 33 SM cases with complete clinical data, the mean age was 39 years and the male/female ratio was 2.8. Most cases were contracted in known endemic regions within Peru: Amazonia (47%), the central jungle (18%), and the northern coast (12%); cases were also found in five (15%) travelers returning from Africa. Plasmodium vivax was most commonly identified (71%) among the severe infections, followed by P. falciparum (18%); mixed infections composed 11% of the group. Among the criteria of severity, jaundice was most common (58%), followed by severe thrombocytopenia (47%), hyperpyrexia (32%), and shock (15%). Plasmodium vivax mono-infection predominated as the etiology of SM in cases acquired in Peru. © The American Society of Tropical Medicine and Hygiene.

Malaria in Brazil: an overview.

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Oliveira-Ferreira, Joseli; Lacerda, Marcus V G; Brasil, Patrícia; Ladislau, José L B; Tauil, Pedro L; Daniel-Ribeiro, Cláudio Tadeu

2010-04-30

Malaria is still a major public health problem in Brazil, with approximately 306,000 registered cases in 2009, but it is estimated that in the early 1940s, around six million cases of malaria occurred each year. As a result of the fight against the disease, the number of malaria cases decreased over the years and the smallest numbers of cases to-date were recorded in the 1960s. From the mid-1960s onwards, Brazil underwent a rapid and disorganized settlement process in the Amazon and this migratory movement led to a progressive increase in the number of reported cases. Although the main mosquito vector (Anopheles darlingi) is present in about 80% of the country, currently the incidence of malaria in Brazil is almost exclusively (99,8% of the cases) restricted to the region of the Amazon Basin, where a number of combined factors favors disease transmission and impair the use of standard control procedures. Plasmodium vivax accounts for 83,7% of registered cases, while Plasmodium falciparum is responsible for 16,3% and Plasmodium malariae is seldom observed. Although vivax malaria is thought to cause little mortality, compared to falciparum malaria, it accounts for much of the morbidity and for huge burdens on the prosperity of endemic communities. However, in the last few years a pattern of unusual clinical complications with fatal cases associated with P. vivax have been reported in Brazil and this is a matter of concern for Brazilian malariologists. In addition, the emergence of P. vivax strains resistant to chloroquine in some reports needs to be further investigated. In contrast, asymptomatic infection by P. falciparum and P. vivax has been detected in epidemiological studies in the states of Rondonia and Amazonas, indicating probably a pattern of clinical immunity in both autochthonous and migrant populations. Seropidemiological studies investigating the type of immune responses elicited in naturally-exposed populations to several malaria vaccine candidates in

Malaria in Brazil: an overview

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Brasil Patrícia

2010-04-01

Full Text Available Abstract Malaria is still a major public health problem in Brazil, with approximately 306 000 registered cases in 2009, but it is estimated that in the early 1940s, around six million cases of malaria occurred each year. As a result of the fight against the disease, the number of malaria cases decreased over the years and the smallest numbers of cases to-date were recorded in the 1960s. From the mid-1960s onwards, Brazil underwent a rapid and disorganized settlement process in the Amazon and this migratory movement led to a progressive increase in the number of reported cases. Although the main mosquito vector (Anopheles darlingi is present in about 80% of the country, currently the incidence of malaria in Brazil is almost exclusively (99,8% of the cases restricted to the region of the Amazon Basin, where a number of combined factors favors disease transmission and impair the use of standard control procedures. Plasmodium vivax accounts for 83,7% of registered cases, while Plasmodium falciparum is responsible for 16,3% and Plasmodium malariae is seldom observed. Although vivax malaria is thought to cause little mortality, compared to falciparum malaria, it accounts for much of the morbidity and for huge burdens on the prosperity of endemic communities. However, in the last few years a pattern of unusual clinical complications with fatal cases associated with P. vivax have been reported in Brazil and this is a matter of concern for Brazilian malariologists. In addition, the emergence of P. vivax strains resistant to chloroquine in some reports needs to be further investigated. In contrast, asymptomatic infection by P. falciparum and P. vivax has been detected in epidemiological studies in the states of Rondonia and Amazonas, indicating probably a pattern of clinical immunity in both autochthonous and migrant populations. Seropidemiological studies investigating the type of immune responses elicited in naturally-exposed populations to several

A community-based health education programme for bio-environmental control of malaria through folk theatre (Kalajatha in rural India

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Tiwari Satyanarayan

2006-12-01

Full Text Available Abstract Background Health education is an important component in disease control programme. Kalajatha is a popular, traditional art form of folk theatre depicting various life processes of a local socio-cultural setting. It is an effective medium of mass communication in the Indian sub-continent especially in rural areas. Using this medium, an operational feasibility health education programme was carried out for malaria control. Methods In December 2001, the Kalajatha events were performed in the evening hours for two weeks in a malaria-affected district in Karnataka State, south India. Thirty local artists including ten governmental and non-governmental organizations actively participated. Impact of this programme was assessed after two months on exposed vs. non-exposed respondents. Results The exposed respondents had significant increase in knowledge and change in attitude about malaria and its control strategies, especially on bio-environmental measures (p Conclusion This study was carried out under the primary health care system involving the local community and various potential partners. Kalajatha conveyed the important messages on malaria control and prevention to the rural community. Similar methods of communication in the health education programme should be intensified with suitable modifications to reach all sectors, if malaria needs to be controlled.

The Summary Index of Malaria Surveillance (SIMS: a stable index of malaria within India

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Sharma Vinod P

2010-02-01

Full Text Available Abstract Background Malaria in India has been difficult to measure. Mortality and morbidity are not comprehensively reported, impeding efforts to track changes in disease burden. However, a set of blood measures has been collected regularly by the National Malaria Control Program in most districts since 1958. Methods Here, we use principal components analysis to combine these measures into a single index, the Summary Index of Malaria Surveillance (SIMS, and then test its temporal and geographic stability using subsets of the data. Results The SIMS correlates positively with all its individual components and with external measures of mortality and morbidity. It is highly consistent and stable over time (1995-2005 and regions of India. It includes measures of both vivax and falciparum malaria, with vivax dominant at lower transmission levels and falciparum dominant at higher transmission levels, perhaps due to ecological specialization of the species. Conclusions This measure should provide a useful tool for researchers looking to summarize geographic or temporal trends in malaria in India, and can be readily applied by administrators with no mathematical or scientific background. We include a spreadsheet that allows simple calculation of the index for researchers and local administrators. Similar principles are likely applicable worldwide, though further validation is needed before using the SIMS outside India.

RTS,S/AS01 malaria vaccine and child mortality

DEFF Research Database (Denmark)

Aaby, Peter; Rodrigues, Amabelia; Kofoed, Poul-Erik

2015-01-01

Comment on Efficacy and safety of RTS,S/AS01 malaria vaccine with or without a booster dose in infants and children in Africa: final results of a phase 3, individually randomised, controlled trial. [Lancet. 2015]......Comment on Efficacy and safety of RTS,S/AS01 malaria vaccine with or without a booster dose in infants and children in Africa: final results of a phase 3, individually randomised, controlled trial. [Lancet. 2015]...

Relative Susceptibilities of ABO Blood Groups to Plasmodium falciparum Malaria in Ghana

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Richmond Afoakwah

2016-01-01

Full Text Available The clinical outcome of falciparum malaria in endemic areas is influenced by erythrocyte polymorphisms including the ABO blood groups. Studies have reported association of ABO blood group to resistance, susceptibility, and severity of P. falciparum malaria infection. Individuals with blood group “A” have been found to be highly susceptible to falciparum malaria whereas blood group “O” is said to confer protection against complicated cases. We analyzed samples from 293 young children less than six years old with malaria in the Korle-Bu Teaching Hospital in Accra, Ghana. It was observed that group O was present in about 16.1% of complicated cases weighed against 40.9% of uncomplicated controls. Individuals with complicated malaria were about twice likely to be of blood groups A and B compared to group O (A versus O, OR = 1.90, 95% CI = 1.59–2.26, P<0.0001; B versus O, OR = 1.82. 95% CI = 1.57–2.23, P<0.0001. Blood group O participants with complicated diseases had low parasitaemia compared to the other blood groups (P<0.0001. This may give blood group O individuals a survival advantage over the other groups in complicated malaria as suggested. Participants with complicated falciparum malaria were generally anaemic and younger than those with uncomplicated disease.

Genome-wide linkage analysis of malaria infection intensity and mild disease.

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Christian Timmann

2007-03-01

Full Text Available Although balancing selection with the sickle-cell trait and other red blood cell disorders has emphasized the interaction between malaria and human genetics, no systematic approach has so far been undertaken towards a comprehensive search for human genome variants influencing malaria. By screening 2,551 families in rural Ghana, West Africa, 108 nuclear families were identified who were exposed to hyperendemic malaria transmission and were homozygous wild-type for the established malaria resistance factors of hemoglobin (HbS, HbC, alpha(+ thalassemia, and glucose-6-phosphate-dehydrogenase deficiency. Of these families, 392 siblings aged 0.5-11 y were characterized for malaria susceptibility by closely monitoring parasite counts, malaria fever episodes, and anemia over 8 mo. An autosome-wide linkage analysis based on 10,000 single-nucleotide polymorphisms was conducted in 68 selected families including 241 siblings forming 330 sib pairs. Several regions were identified which showed evidence for linkage to the parasitological and clinical phenotypes studied, among them a prominent signal on Chromosome 10p15 obtained with malaria fever episodes (asymptotic z score = 4.37, empirical p-value = 4.0 x 10(-5, locus-specific heritability of 37.7%; 95% confidence interval, 15.7%-59.7%. The identification of genetic variants underlying the linkage signals may reveal as yet unrecognized pathways influencing human resistance to malaria.

Effect of schistosoma infection on malaria immune response: A systematic review.

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Yesuf, Elias Ali; Dejene, Tariku

2011-01-01

Background Worldwide an estimated 225 million cases and about 800, 000 deaths due to malaria were documented in 2009. Malaria vaccines have been developed as a malaria control strategy. Immune response to these vaccines might be affected by the blood fluke schistosoma which is often co-endemic with malaria in Sub-Saharan Africa where most of phase II and Phase III malaria vaccine trials were conducted.Objectives To systematically search, appraise and synthesize the best available evidence on the effect of schistosoma infection on the immune response to malaria antigens and provide direction to future malaria vaccination trials.Types of participants The review considered studies with above 5 year old individuals as participants.Phenomenon of interest The phenomenon of interest was the presence of schistosoma infectionTypes of outcomes Blood serum levels of Th1 and Th2 specific to Merozoite Surface Proteins 1, 2, and 3 of malaria were considered as primary outcomes. While blood serum levels of IgG1, IgG2, IgG3, IFN-γ, IL-10 and TGF-β directed against Merozoite Surface Proteins were considered as secondary outcomes.Types of studies Studies with any quantitative study designs were considered for inclusion.Search Strategy Any quantitative English language articles published between 1994 and April 2011 were sought using a comprehensive search strategy.Assessment of methodological quality It was done using Joanna Briggs Institutes' Meta Analysis of Statistical Assessment and Review Instrument critical appraisal tools.Data extraction Data extraction was carried out using the Joanna Briggs Institute Meta Analysis of Statistical Assessment and Review Instrument data extraction tool.Data synthesis Meta- analysis was conducted using random effects model with an inverse variance method with RevMan5 software. Heterogeneity between the studies was assessed using ξ test at a p-value of SMD (95% CI), 0.15 (-2.00, 2.31), p=0.89.Similarly a small and statistically not significant

Malaria protection in Sierra Leone during the Ebola outbreak 2014/15; The UK military experience with malaria chemoprophylaxis Sep 14-Feb 15.

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Tuck, Jeremy; Williams, Jonathan

The UK deployed a task force to Sierra Leone to assist in ending the 2014/15 Ebola outbreak. Malaria protection was based on existing Defence Policy which saw a wide range of bite prevention measures deployed. Atovaquone/Proguanil ("A/P"), Doxycycline ("D") and Mefloquine ("M") were the chemoprophylactic medications that were prescribed. A survey was undertaken to audit the Adverse Effect (AE) burden experienced by the population. A questionnaire based survey was administered that sought information on individuals' experiences with malaria chemoprophylaxis. 337 personnel were eligible to take part and 151 (46.3%) individuals returned questionnaires. The reported AE rates for the three drugs were "A/P" 28% of the respondents, "D" 25% and "M" 23.1%. 24 individuals (15.9%) reported 1 AE while 34 (22.5%) reported multiple AEs. Eight (5.3%) individuals changed medication (Five "A/P", two "M" and one "D") because of unacceptable AE but no significant neuro/psychological conditions were reported. The malaria attack rate for the deployed population was 0.4 cases per thousand person weeks which is very low when compared to other military deployments to the West African Area. UK Defence policy is effective in the way it balances the risk of malaria with that of AE due to chemoprophylaxis. "M" remains an acceptable chemoprophylactic agent for a section of the population. Copyright © 2016. Published by Elsevier Ltd.

Preliminary analysis of accidents on the Santa QuitÉria Project: occupationally exposed individuals

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Anjos, Gullit Diego C. dos, E-mail: gullitcardoso@inb.gov.br [Indústrias Nucleares do Brasil (INB), Rio de Janeiro, RJ (Brazil)

2017-07-01

The Santa Quitéria Project (PSQ) is an enterprise that aims at the production of phosphate compounds as main products, and of uranium concentrates as by-products from minerals of the Itataia deposit. The intended area for implementation of the project is located in the municipality of Santa Quitéria, north central region of the State of Ceará. The U.S. Nuclear Regulatory Commission lists the basic design accidents for a Uranium Processing Plant, such as the PSQ. Among all these scenarios, fire in uranium extraction cells was the one with the highest doses released. For simulation of the fire event, the atmospheric dispersion model used was the standard Gaussian plume model. The doses were calculated for two sets of meteorological conditions: stability class F, with wind velocity of 1 m/s and class D stability with wind velocity of 4.5 m/s. For PSQ, it was considered that there will be no public individual until after 2000 meters from the release point. The doses corresponding to the occupationally exposed individuals are: 2.0E-3 mSv (class D) and 5 mSv (Class F), 300 meters away from the event. Analyzing the results, it can be concluded that there are no significant radiological consequences for the occupationally exposed individual, both in the stability class D and the F. The doses of the workers are well below the levels that could cause deterministic effects. Even if an occupationally exposed individual were exposed for 12 hours in the center of the plume, the dose received would not exceed the annual limit established by CNEN. (author)

Comparative gene expression profiling of P. falciparum malaria parasites exposed to three different histone deacetylase inhibitors.

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Katherine T Andrews

Full Text Available Histone deacetylase (HDAC inhibitors are being intensively pursued as potential new drugs for a range of diseases, including malaria. HDAC inhibitors are also important tools for the study of epigenetic mechanisms, transcriptional control, and other important cellular processes. In this study the effects of three structurally related antimalarial HDAC inhibitors on P. falciparum malaria parasite gene expression were compared. The three hydroxamate-based compounds, trichostatin A (TSA, suberoylanilide hydroxamic acid (SAHA; Vorinostat® and a 2-aminosuberic acid derivative (2-ASA-9, all caused profound transcriptional effects, with ~2-21% of genes having >2-fold altered expression following 2 h exposure to the compounds. Only two genes, alpha tubulin II and a hydrolase, were up-regulated by all three compounds after 2 h exposure in all biological replicates examined. The transcriptional changes observed after 2 h exposure to HDAC inhibitors were found to be largely transitory, with only 1-5% of genes being regulated after removing the compounds and culturing for a further 2 h. Despite some structural similarity, the three inhibitors caused quite diverse transcriptional effects, possibly reflecting subtle differences in mode of action or cellular distribution. This dataset represents an important contribution to our understanding of how HDAC inhibitors act on malaria parasites and identifies alpha tubulin II as a potential transcriptional marker of HDAC inhibition in malaria parasites that may be able to be exploited for future development of HDAC inhibitors as new antimalarial agents.

A validated agent-based model to study the spatial and temporal heterogeneities of malaria incidence in the rainforest environment.

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Pizzitutti, Francesco; Pan, William; Barbieri, Alisson; Miranda, J Jaime; Feingold, Beth; Guedes, Gilvan R; Alarcon-Valenzuela, Javiera; Mena, Carlos F

2015-12-22

The Amazon environment has been exposed in the last decades to radical changes that have been accompanied by a remarkable rise of both Plasmodium falciparum and Plasmodium vivax malaria. The malaria transmission process is highly influenced by factors such as spatial and temporal heterogeneities of the environment and individual-based characteristics of mosquitoes and humans populations. All these determinant factors can be simulated effectively trough agent-based models. This paper presents a validated agent-based model of local-scale malaria transmission. The model reproduces the environment of a typical riverine village in the northern Peruvian Amazon, where the malaria transmission is highly seasonal and apparently associated with flooding of large areas caused by the neighbouring river. Agents representing humans, mosquitoes and the two species of Plasmodium (P. falciparum and P. vivax) are simulated in a spatially explicit representation of the environment around the village. The model environment includes: climate, people houses positions and elevation. A representation of changes in the mosquito breeding areas extension caused by the river flooding is also included in the simulation environment. A calibration process was carried out to reproduce the variations of the malaria monthly incidence over a period of 3 years. The calibrated model is also able to reproduce the spatial heterogeneities of local scale malaria transmission. A "what if" eradication strategy scenario is proposed: if the mosquito breeding sites are eliminated through mosquito larva habitat management in a buffer area extended at least 200 m around the village, the malaria transmission is eradicated from the village. The use of agent-based models can reproduce effectively the spatiotemporal variations of the malaria transmission in a low endemicity environment dominated by river floodings like in the Amazon.

The sterilizing effect of pyriproxyfen on the malaria vector Anopheles gambiae: physiological impact on ovaries development.

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Koama, Bayili; Namountougou, Moussa; Sanou, Roger; Ndo, Sévérin; Ouattara, Abdoulaye; Dabiré, Roch K; Malone, David; Diabaté, Abdoulaye

2015-03-04

Adult females An. gambiae were exposed in 3 min cone test to treated nets with PPF before or after they were blood fed. The effects of PPF on ovaries development, females oviposition and eggs hatching were assessed. Both unfed and fed mosquitoes exposed to PPF exhibited nearly complete inhibition of fecundity (70-100%) and fertility (90-100%). After females have been exposed once to PPF, the sterilizing effect on their fecundity was observed over 3 consecutive blood meals suggesting that PPF might have an irreversible sterilizing effect. Observation of the ovaries of exposed females to PPF under microscope revealed that the ovaries failed to develop even after several blood meals. The combination of PPF to pyrethroids on bednets could provide better malaria control tool and prevent the further development and spread of pyrethroid resistance in malaria vectors.

Spatio-Temporal Dynamics of Asymptomatic Malaria: Bridging the Gap Between Annual Malaria Resurgences in a Sahelian Environment.

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Coulibaly, Drissa; Travassos, Mark A; Tolo, Youssouf; Laurens, Matthew B; Kone, Abdoulaye K; Traore, Karim; Sissoko, Mody; Niangaly, Amadou; Diarra, Issa; Daou, Modibo; Guindo, Boureima; Rebaudet, Stanislas; Kouriba, Bourema; Dessay, Nadine; Piarroux, Renaud; Plowe, Christopher V; Doumbo, Ogobara K; Thera, Mahamadou A; Gaudart, Jean

2017-12-01

In areas of seasonal malaria transmission, the incidence rate of malaria infection is presumed to be near zero at the end of the dry season. Asymptomatic individuals may constitute a major parasite reservoir during this time. We conducted a longitudinal analysis of the spatio-temporal distribution of clinical malaria and asymptomatic parasitemia over time in a Malian town to highlight these malaria transmission dynamics. For a cohort of 300 rural children followed over 2009-2014, periodicity and phase shift between malaria and rainfall were determined by spectral analysis. Spatial risk clusters of clinical episodes or carriage were identified. A nested-case-control study was conducted to assess the parasite carriage factors. Malaria infection persisted over the entire year with seasonal peaks. High transmission periods began 2-3 months after the rains began. A cluster with a low risk of clinical malaria in the town center persisted in high and low transmission periods. Throughout 2009-2014, cluster locations did not vary from year to year. Asymptomatic and gametocyte carriage were persistent, even during low transmission periods. For high transmission periods, the ratio of asymptomatic to clinical cases was approximately 0.5, but was five times higher during low transmission periods. Clinical episodes at previous high transmission periods were a protective factor for asymptomatic carriage, but carrying parasites without symptoms at a previous high transmission period was a risk factor for asymptomatic carriage. Stable malaria transmission was associated with sustained asymptomatic carriage during dry seasons. Control strategies should target persistent low-level parasitemia clusters to interrupt transmission.

Malaria and helminth co-infections in school and preschool children

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Kinung'hi, Safari M; Magnussen, Pascal; Kaatano, Godfrey M

2014-01-01

Malaria, schistosomiasis and soil transmitted helminth infections (STH) are important parasitic infections in Sub-Saharan Africa where a significant proportion of people are exposed to co-infections of more than one parasite. In Tanzania, these infections are a major public health problem particu...

Utility of health facility-based malaria data for malaria surveillance.

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Yaw A Afrane

Full Text Available Currently, intensive malaria control programs are being implemented in Africa to reduce the malaria burden. Clinical malaria data from hospitals are valuable for monitoring trends in malaria morbidity and for evaluating the impacts of these interventions. However, the reliability of hospital-based data for true malaria incidence is often questioned because of diagnosis accuracy issues and variation in access to healthcare facilities among sub-groups of the population. This study investigated how diagnosis and treatment practices of malaria cases in hospitals affect reliability of hospital malaria data.The study was undertaken in health facilities in western Kenya. A total of 3,569 blood smears were analyzed after being collected from patients who were requested by clinicians to go to the hospital's laboratory for malaria testing. We applied several quality control measures for clinical malaria diagnosis. We compared our slide reading results with those from the hospital technicians. Among the 3,390 patients whose diagnoses were analyzed, only 36% had clinical malaria defined as presence of any level of parasitaemia and fever. Sensitivity and specificity of clinicians' diagnoses were 60.1% (95% CI: 61.1-67.5 and 75.0% (95% CI: 30.8-35.7, respectively. Among the 980 patients presumptively treated with an anti-malarial by the clinicians without laboratory diagnosis, only 47% had clinical malaria.These findings revealed substantial over-prescription of anti-malarials and misdiagnosis of clinical malaria. More than half of the febrile cases were not truly clinical malaria, but were wrongly diagnosed and treated as such. Deficiency in malaria diagnosis makes health facility data unreliable for monitoring trends in malaria morbidity and for evaluating impacts of malaria interventions. Improving malaria diagnosis should be a top priority in rural African health centers.

Testing Local Adaptation in a Natural Great Tit-Malaria System: An Experimental Approach.

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Tania Jenkins

Full Text Available Finding out whether Plasmodium spp. are coevolving with their vertebrate hosts is of both theoretical and applied interest and can influence our understanding of the effects and dynamics of malaria infection. In this study, we tested for local adaptation as a signature of coevolution between malaria blood parasites, Plasmodium spp. and its host, the great tit, Parus major. We conducted a reciprocal transplant experiment of birds in the field, where we exposed birds from two populations to Plasmodium parasites. This experimental set-up also provided a unique opportunity to study the natural history of malaria infection in the wild and to assess the effects of primary malaria infection on juvenile birds. We present three main findings: i there was no support for local adaptation; ii there was a male-biased infection rate; iii infection occurred towards the end of the summer and differed between sites. There were also site-specific effects of malaria infection on the hosts. Taken together, we present one of the few experimental studies of parasite-host local adaptation in a natural malaria system, and our results shed light on the effects of avian malaria infection in the wild.

Use of short message service (SMS to improve malaria chemoprophylaxis compliance after returning from a malaria endemic area

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Boutin Jean-Paul

2009-10-01

Full Text Available Abstract Background Malaria chemoprophylaxis compliance is suboptimal among French soldiers despite the availability of free malaria chemoprophylaxis and repeated health education before, during and after deployment to malaria endemic areas. Methods In 2007, a randomized controlled study was performed among a cohort of French soldiers returning from Côte d'Ivoire to assess the feasibility and acceptability of sending a daily short message service (SMS reminder message via mobile device to remind soldiers to take their malaria chemoprophylaxis, and to assess the impact of the daily reminder SMS on chemoprophylaxis compliance. Malaria chemoprophylaxis consisted of a daily dose of 100 mg doxycycline monohydrate, which began upon arrival in Côte d'Ivoire and was to be continued for 28 days following return to France. Feasibility and acceptability were assessed by questionnaire. Cohort members were followed for a 28 day period, with compliance assessed by use of an electronic medication monitoring device, from which several indicators were developed: daily proportion of compliant individuals, average number of pills taken, and early discontinuation. Results Among 424 volunteers randomized to the study, 47.6% were assigned to the SMS group and 52.3% to the control group. Approximately 90% of subjects assigned to the SMS group received a daily SMS at midday during the study. Persons of the SMS group agreed more frequently that SMS reminders were very useful and that the device was not annoying. Compliance did not vary significantly between groups across the compliance indicators. Conclusion SMS did not increase malaria chemoprophylaxis compliance above baseline, likely because the persons did not benefit from holidays after the return and stayed together. So the reminder by SMS was noted by all subjects of the study. Another study should be done to confirm these results on soldiers going on holidays from employment after return or with individual

Performance of a High-Sensitivity Rapid Diagnostic Test for Plasmodium falciparum Malaria in Asymptomatic Individuals from Uganda and Myanmar and Naive Human Challenge Infections.

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Das, Smita; Jang, Ihn Kyung; Barney, Becky; Peck, Roger; Rek, John C; Arinaitwe, Emmanuel; Adrama, Harriet; Murphy, Maxwell; Imwong, Mallika; Ling, Clare L; Proux, Stephane; Haohankhunnatham, Warat; Rist, Melissa; Seilie, Annette M; Hanron, Amelia; Daza, Glenda; Chang, Ming; Nakamura, Tomoka; Kalnoky, Michael; Labarre, Paul; Murphy, Sean C; McCarthy, James S; Nosten, Francois; Greenhouse, Bryan; Allauzen, Sophie; Domingo, Gonzalo J

2017-11-01

Sensitive field-deployable diagnostic tests can assist malaria programs in achieving elimination. The performance of a new Alere™ Malaria Ag P.f Ultra Sensitive rapid diagnostic test (uRDT) was compared with the currently available SD Bioline Malaria Ag P.f RDT in blood specimens from asymptomatic individuals in Nagongera, Uganda, and in a Karen Village, Myanmar, representative of high- and low-transmission areas, respectively, as well as in pretreatment specimens from study participants from four Plasmodium falciparum -induced blood-stage malaria (IBSM) studies. A quantitative reverse transcription PCR (qRT-PCR) and a highly sensitive enzyme-linked immunosorbent assay (ELISA) test for histidine-rich protein II (HRP2) were used as reference assays. The uRDT showed a greater than 10-fold lower limit of detection for HRP2 compared with the RDT. The sensitivity of the uRDT was 84% and 44% against qRT-PCR in Uganda and Myanmar, respectively, and that of the RDT was 62% and 0% for the same two sites. The specificities of the uRDT were 92% and 99.8% against qRT-PCR for Uganda and Myanmar, respectively, and 99% and 99.8% against the HRP2 reference ELISA. The RDT had specificities of 95% and 100% against qRT-PCR for Uganda and Myanmar, respectively, and 96% and 100% against the HRP2 reference ELISA. The uRDT detected new infections in IBSM study participants 1.5 days sooner than the RDT. The uRDT has the same workflow as currently available RDTs, but improved performance characteristics to identify asymptomatic malaria infections. The uRDT may be a useful tool for malaria elimination strategies.

Immunological alterations in individuals exposed to metal(loid)s in the Panasqueira mining area, Central Portugal.

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Coelho, Patrícia; García-Lestón, Julia; Costa, Solange; Costa, Carla; Silva, Susana; Fuchs, Dietmar; Geisler, Simon; Dall'Armi, Valentina; Zoffoli, Roberto; Bonassi, Stefano; Pásaro, Eduardo; Laffon, Blanca; Teixeira, João Paulo

2014-03-15

Environmental studies performed in Panasqueira mine area (central Portugal) identified high concentrations of several metal(loid)s in environmental media, and individuals environmentally and occupationally exposed showed higher levels of As, Cr, Mg, Mn, Mo, Pb and Zn in blood, urine, hair and nails when compared to unexposed controls. To evaluate the presence of immunological alterations attributable to environmental contamination, we quantified neopterin, kynurenine, tryptophan, and nitrite concentrations in plasma, and analysed the percentage of several lymphocytes subsets, namely CD3(+), CD4(+) and CD8(+) T-cells, CD19(+) B-cells, and CD16(+)56(+) natural killer (NK) cells in a group of individuals previously tested for metal(loid) levels in different biological matrices. The environmentally exposed group had significantly lower levels of %CD8(+) and higher CD4(+)/CD8(+) ratios, whereas the occupationally exposed individuals showed significant decreases in %CD3(+) and %CD4(+), and significant increases in %CD16(+)56(+), when compared to controls. Analysed biomarkers were found to be influenced by age, particularly neopterin, kynurenine and kynurenine to tryptophan ratio (Kyn/Trp) with significantly higher levels in older individuals, and %CD3(+), %CD8(+) and %CD19(+) with significantly lower values in older individuals. Males environmentally exposed showed significantly lower values of %CD19(+) when compared to control females. The concentration of Pb in toenails was associated to the level of neopterin, kynurenine and Kyn/Trp ratio (all direct), and the concentration of Mn in blood to the level of %CD8(+), %CD19(+) (both inverse) and CD4(+)/CD8(+) ratio (direct). Overall our results show that the metal(loid) contamination in Panasqueira mine area induced immunotoxic effects in exposed populations, possibly increasing susceptibility to diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

Using Structured Additive Regression Models to Estimate Risk Factors of Malaria: Analysis of 2010 Malawi Malaria Indicator Survey Data

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Chirombo, James; Lowe, Rachel; Kazembe, Lawrence

2014-01-01

Background After years of implementing Roll Back Malaria (RBM) interventions, the changing landscape of malaria in terms of risk factors and spatial pattern has not been fully investigated. This paper uses the 2010 malaria indicator survey data to investigate if known malaria risk factors remain relevant after many years of interventions. Methods We adopted a structured additive logistic regression model that allowed for spatial correlation, to more realistically estimate malaria risk factors. Our model included child and household level covariates, as well as climatic and environmental factors. Continuous variables were modelled by assuming second order random walk priors, while spatial correlation was specified as a Markov random field prior, with fixed effects assigned diffuse priors. Inference was fully Bayesian resulting in an under five malaria risk map for Malawi. Results Malaria risk increased with increasing age of the child. With respect to socio-economic factors, the greater the household wealth, the lower the malaria prevalence. A general decline in malaria risk was observed as altitude increased. Minimum temperatures and average total rainfall in the three months preceding the survey did not show a strong association with disease risk. Conclusions The structured additive regression model offered a flexible extension to standard regression models by enabling simultaneous modelling of possible nonlinear effects of continuous covariates, spatial correlation and heterogeneity, while estimating usual fixed effects of categorical and continuous observed variables. Our results confirmed that malaria epidemiology is a complex interaction of biotic and abiotic factors, both at the individual, household and community level and that risk factors are still relevant many years after extensive implementation of RBM activities. PMID:24991915

IL4 gene polymorphism and previous malaria experiences manipulate anti-Plasmodium falciparum antibody isotype profiles in complicated and uncomplicated malaria

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Kalambaheti Thareerat

2009-12-01

Full Text Available Abstract Background The IL4-590 gene polymorphism has been shown to be associated with elevated levels of anti-Plasmodium falciparum IgG antibodies and parasite intensity in the malaria protected Fulani of West Africa. This study aimed to investigate the possible impact of IL4-590C/T polymorphism on anti-P. falciparum IgG subclasses and IgE antibodies levels and the alteration of malaria severity in complicated and uncomplicated malaria patients with or without previous malaria experiences. Methods Anti-P.falciparum IgG subclasses and IgE antibodies in plasma of complicated and uncomplicated malaria patients with or without previous malaria experiences were analysed using ELISA. IL4-590 polymorphisms were genotyped using RFLP-PCR. Statistical analyses of the IgG subclass levels were done by Oneway ANOVA. Genotype differences were tested by Chi-squared test. Results The IL4-590T allele was significantly associated with anti-P. falciparum IgG3 antibody levels in patients with complicated (P = 0.031, but not with uncomplicated malaria (P = 0.622. Complicated malaria patients with previous malaria experiences carrying IL4-590TT genotype had significantly lower levels of anti-P. falciparum IgG3 (P = 0.0156, while uncomplicated malaria patients with previous malaria experiences carrying the same genotype had significantly higher levels (P = 0.0206 compared to their IL4-590 counterparts. The different anti-P. falciparum IgG1 and IgG3 levels among IL4 genotypes were observed. Complicated malaria patients with previous malaria experiences tended to have lower IgG3 levels in individuals carrying TT when compared to CT genotypes (P = 0.075. In contrast, complicated malaria patients without previous malaria experiences carrying CC genotype had significantly higher anti-P. falciparum IgG1 than those carrying either CT or TT genotypes (P = 0.004, P = 0.002, respectively. Conclusion The results suggest that IL4-590C or T alleles participated differently in the

Comparison of clinical and parasitological data from controlled human malaria infection trials.

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Meta Roestenberg

Full Text Available Exposing healthy human volunteers to Plasmodium falciparum-infected mosquitoes is an accepted tool to evaluate preliminary efficacy of malaria vaccines. To accommodate the demand of the malaria vaccine pipeline, controlled infections are carried out in an increasing number of centers worldwide. We assessed their safety and reproducibility.We reviewed safety and parasitological data from 128 malaria-naïve subjects participating in controlled malaria infection trials conducted at the University of Oxford, UK, and the Radboud University Nijmegen Medical Center, The Netherlands. Results were compared to a report from the US Military Malaria Vaccine Program.We show that controlled human malaria infection trials are safe and demonstrate a consistent safety profile with minor differences in the frequencies of arthralgia, fatigue, chills and fever between institutions. But prepatent periods show significant variation. Detailed analysis of Q-PCR data reveals highly synchronous blood stage parasite growth and multiplication rates.Procedural differences can lead to some variation in safety profile and parasite kinetics between institutions. Further harmonization and standardization of protocols will be useful for wider adoption of these cost-effective small-scale efficacy trials. Nevertheless, parasite growth rates are highly reproducible, illustrating the robustness of controlled infections as a valid tool for malaria vaccine development.

Dynamics of positional warfare malaria: Finland and Korea compared.

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Huldén, Lena; Huldén, Larry

2008-09-08

A sudden outbreak of vivax malaria among Finnish troops in SE-Finland and along the front line in Hanko peninsula in the southwest occurred in 1941 during World War II. The common explanation has been an invasion of infective Anopheles mosquitoes from the Russian troops crossing the front line between Finland and Soviet Union. A revised explanation is presented based on recent studies of Finnish malaria. The exact start of the epidemic and the phenology of malaria cases among the Finnish soldiers were reanalyzed. The results were compared with the declining malaria in Finland. A comparison with a corresponding situation starting in the 1990's in Korea was performed. The malaria cases occurred in July in 1941 when it was by far too early for infective mosquitoes to be present. The first Anopheles mosquitoes hatched at about the same time as the first malaria cases were observed among the Finnish soldiers. It takes about 3-6 weeks for the completion of the sporogony in Finland. The new explanation is that soldiers in war conditions were suddenly exposed to uninfected mosquitoes and those who still were carriers of hypnozoites developed relapses triggered by these mosquitoes. It is estimated that about 0.5% of the Finnish population still were carriers of hypnozoites in the 1940's. A corresponding outbreak of vivax malaria in Korea in the 1990's is similarly interpreted as relapses from activated hypnozoites among Korean soldiers. The significance of the mosquito induced relapses is emphasized by two benefits for the Plasmodium. There is a synchronous increase of gametocytes when new mosquitoes emerge. It also enables meiotic recombination between different strains of the Plasmodium. The malaria peak during the positional warfare in the 1940's was a short outbreak during the last phase of declining indigenous malaria in Finland. The activation of hypnozoites among a large number of soldiers and subsequent medication contributed to diminishing the reservoir of malaria

Temporal and speech processing skills in normal hearing individuals exposed to occupational noise.

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Kumar, U Ajith; Ameenudin, Syed; Sangamanatha, A V

2012-01-01

Prolonged exposure to high levels of occupational noise can cause damage to hair cells in the cochlea and result in permanent noise-induced cochlear hearing loss. Consequences of cochlear hearing loss on speech perception and psychophysical abilities have been well documented. Primary goal of this research was to explore temporal processing and speech perception Skills in individuals who are exposed to occupational noise of more than 80 dBA and not yet incurred clinically significant threshold shifts. Contribution of temporal processing skills to speech perception in adverse listening situation was also evaluated. A total of 118 participants took part in this research. Participants comprised three groups of train drivers in the age range of 30-40 (n= 13), 41 50 ( = 13), 41-50 (n = 9), and 51-60 (n = 6) years and their non-noise-exposed counterparts (n = 30 in each age group). Participants of all the groups including the train drivers had hearing sensitivity within 25 dB HL in the octave frequencies between 250 and 8 kHz. Temporal processing was evaluated using gap detection, modulation detection, and duration pattern tests. Speech recognition was tested in presence multi-talker babble at -5dB SNR. Differences between experimental and control groups were analyzed using ANOVA and independent sample t-tests. Results showed a trend of reduced temporal processing skills in individuals with noise exposure. These deficits were observed despite normal peripheral hearing sensitivity. Speech recognition scores in the presence of noise were also significantly poor in noise-exposed group. Furthermore, poor temporal processing skills partially accounted for the speech recognition difficulties exhibited by the noise-exposed individuals. These results suggest that noise can cause significant distortions in the processing of suprathreshold temporal cues which may add to difficulties in hearing in adverse listening conditions.

Temporal and speech processing skills in normal hearing individuals exposed to occupational noise

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U Ajith Kumar

2012-01-01

Full Text Available Prolonged exposure to high levels of occupational noise can cause damage to hair cells in the cochlea and result in permanent noise-induced cochlear hearing loss. Consequences of cochlear hearing loss on speech perception and psychophysical abilities have been well documented. Primary goal of this research was to explore temporal processing and speech perception Skills in individuals who are exposed to occupational noise of more than 80 dBA and not yet incurred clinically significant threshold shifts. Contribution of temporal processing skills to speech perception in adverse listening situation was also evaluated. A total of 118 participants took part in this research. Participants comprised three groups of train drivers in the age range of 30-40 (n= 13, 41 50 ( = 13, 41-50 (n = 9, and 51-60 (n = 6 years and their non-noise-exposed counterparts (n = 30 in each age group. Participants of all the groups including the train drivers had hearing sensitivity within 25 dB HL in the octave frequencies between 250 and 8 kHz. Temporal processing was evaluated using gap detection, modulation detection, and duration pattern tests. Speech recognition was tested in presence multi-talker babble at -5dB SNR. Differences between experimental and control groups were analyzed using ANOVA and independent sample t-tests. Results showed a trend of reduced temporal processing skills in individuals with noise exposure. These deficits were observed despite normal peripheral hearing sensitivity. Speech recognition scores in the presence of noise were also significantly poor in noise-exposed group. Furthermore, poor temporal processing skills partially accounted for the speech recognition difficulties exhibited by the noise-exposed individuals. These results suggest that noise can cause significant distortions in the processing of suprathreshold temporal cues which may add to difficulties in hearing in adverse listening conditions.

High-frequency Audiometry Hearing on Monitoring of Individuals Exposed to Occupational Noise: A Systematic Review.

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Antonioli, Cleonice Aparecida Silva; Momensohn-Santos, Teresa Maria; Benaglia, Tatiana Aparecida Silva

2016-07-01

The literature reports on high-frequency audiometry as one of the exams used on hearing monitoring of individuals exposed to high sound pressure in their work environment, due to the method́s greater sensitivity in early identification of hearing loss caused by noise. The frequencies that compose the exam are generally between 9 KHz and 20KHz, depending on the equipment. This study aims to perform a retrospective and secondary systematic revision of publications on high-frequency audiometry on hearing monitoring of individuals exposed to occupational noise. This systematic revision followed the methodology proposed in the Cochrane Handbook, focusing on the question: "Is High-frequency Audiometry more sensitive than Conventional Audiometry in the screening of early hearing loss individuals exposed to occupational noise?" The search was based on PubMed data, Base, Web of Science (Capes), Biblioteca Virtual em Saúde (BVS), and in the references cited in identified and selected articles. The search resulted in 6059 articles in total. Of these, only six studies were compatible with the criteria proposed in this study. The performed meta-analysis does not definitively answer the study's proposed question. It indicates that the 16 KHz high frequency audiometry (HFA) frequency is sensitive in early identification of hearing loss in the control group (medium difference (MD = 8.33)), as well as the 4 KHz frequency (CA), this one being a little less expressive (MD = 5.72). Thus, others studies are necessary to confirm the HFA importance for the early screening of hearing loss on individuals exposed to noise at the workplace.

TOLLIP gene variant is associated with Plasmodium vivax malaria in the Brazilian Amazon.

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Brasil, Larissa W; Barbosa, Laila R A; de Araujo, Felipe J; da Costa, Allyson G; da Silva, Luan D O; Pinheiro, Suzana K; de Almeida, Anne C G; Kuhn, Andrea; Vitor-Silva, Sheila; de Melo, Gisely C; Monteiro, Wuelton M; de Lacerda, Marcus V G; Ramasawmy, Rajendranath

2017-03-13

Toll-interacting protein is a negative regulator in the TLR signaling cascade, particularly by impeding the TLR2 and, TLR4 pathway. Recently, TOLLIP was shown to regulate human TLR signaling pathways. Two common TOLLIP polymorphisms (rs5743899 and rs3750920) were reported to be influencing IL-6, TNF and IL-10 expression. In this study, TOLLIP variants were investigated to their relation to Plasmodium vivax malaria in the Brazilian Amazon. This cohort study was performed in the municipalities of Careiro and, Manaus, in Western Brazilian Amazon. A total of 319 patients with P. vivax malaria and, 263 healthy controls with no previous history of malaria were included in the study. Genomic DNA was extracted from blood collected on filter paper, using the QIAamp ® DNA Mini Kit, according to the manufacturer's suggested protocol. The rs5743899 and rs3750920 polymorphisms of the TOLLIP gene were typed by PCR-RFLP. Homozygous individuals for the rs3750920 T allele gene had twice the risk of developing malaria when compared to individuals homozygous for the C allele (OR 2.0 [95% CI 1.23-3.07]; p = 0.004). In the dominant model, carriers the C allele indicates protection to malaria, carriers of the C allele were compared to individuals with the T allele, and the difference is highly significant (OR 0.52 [95% CI 0.37-0.76]; p = 0.0006). The linkage disequilibrium between the two polymorphisms was weak (r 2  = 0.037; D' = 0.27). These findings suggest that genes involved in the TLRs-pathway may be involved in malaria susceptibility. The association of the TOLLIP rs3750920 T allele with susceptibility to malaria further provides evidence that genetic variations in immune response genes may predispose individuals to malaria.

Hari Malaria Sedunia 2013 Investasi Di Masa Depan. Taklukkan Malaria

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Hotnida Sitorus

2017-02-01

Full Text Available Abstract Malaria is still the global health problems, World Health Organization estimates that malaria causes death of approximately 660.000 in 2010, most of the age of the children in the region of sub-Saharan Africa. World Malaria Day 2013 assigned the theme “Invest in the future. Defeat malaria”. It takes political will and collective action to jointly combat malaria through malaria elimination. Needed more new donors to be involved in global partnerships against malaria. These partnerships exist, one of which is support of funding or facility for malaria endemic countries which do not have sufficient resources to control malaria. A lot of effort has been done or is still in the development stage. The use of long-lasting insecticidal nets appropriately can reduce malaria cases. The use of rapid diagnostic test, especially in remote areas and health facility with no microscopy, is very beneficial for patients to get prompt treatment. The control of malaria through integrated vector management is a rational decision making process to optimize the use of resources in the control of vector. Sterile insect technique has a promising prospect and expected to replace the role of chemical insecticides that have negative impact both on the environment and target vector (resistance. Keywords: Malaria, long-lasting insecticidal nets, rapid diagnostic test Abstrak Malaria masih menjadi masalah kesehatan dunia, Organisasi Kesehatan Dunia (WHO memperkirakan malaria menyebabkan kurang lebih 660.000 kematian pada tahun 2010, kebanyakan usia anak-anak di wilayah Sub-Sahara Afrika. Pada peringatan hari malaria dunia tahun 2013 ditetapkan tema “Investasi di masa depan. Taklukkan malaria”. Dibutuhkan kemauan politik dan tindakan kolektif untuk bersama-sama memerangi malaria melalui gerakan eliminasi malaria. Diperlukan lebih banyak donor baru untuk turut terlibat dalam kemitraan global melawan malaria. Wujud kemitraan tersebut salah satunya adalah

Liver function assessment in malaria, typhoid and malaria-typhoid co-infection in Aba, Abia State, Nigeria.

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Enemchukwu, B N; Ibe, C C; Udedi, S C; Iroha, A; Ubaoji, K I; Ogundapo, S S

2014-06-01

Malaria and typhoid fever are among the most endemic diseases in the tropics and are associated with poverty and underdevelopment with significant morbidity and mortality. Both diseases can lead to liver damage if not properly treated. The liver function assessment was therefore conducted on (90) volunteer patients; comprising (30) patients with malaria only, (30) with typhoid only and (30) with malaria-typhoid co-infection randomly selected from Abia State University Teaching Hospital, Aba, Abia State, Nigeria and (20) healthy individuals were used as control. Blood samples collected from these subjects were screened for malaria parasite and Staphylococcus typhi using standard methods. Mean serum levels of ALP (112.55±84.23), AST (31.33±12.80), ALT (23.10±11.84), TB (19.43±5.02), CB (5.91±3.03) and ALP (116.69±48.68), AST (28.33±11.72), ALT (22.8±5.94), TB (19.31±5.84),CB (5.60±2.50) were obtained for those subjects with malaria and typhoid respectively and subjects with malaria-typhoid co-infection recorded the following; ALP (134.33±56.62), AST (33.97±8.43), ALT (24.40±4.37),TB (21.27±2.96),CB (6.58±3.10) while the control subjects had mean serum levels ofALP (71.05±18.18), AST (16.65±7.45), ALT (13.85±6.09), TB (10.05±4.85) and CB (3.00±1.67). These mean values were subjected to a statistical test using students t-test which revealed a significant increase (p<0.05).The results suggest that malaria, typhoid and malaria-typhoid co-infection can elevate ALP, AST, ALT, TB and CB serum levels and can lead to liver damage if not properly treated.

Antibody levels against rabies among occupationally exposed individuals in a Nigerian University

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Babasola O. Olugasa

2010-03-01

Full Text Available The authors investigated the levels of anti-glycoprotein antibodies against rabies virus in the sera of occupationally exposed humans at the University of Ibadan, Nigeria. A quantitative indirect enzyme-linked immunosorbent assay (ELISA was used to detect rabies virus anti-glycoprotein antibodies in sera from 20 zoological garden workers, 20 veterinarians and 30 clinical veterinary students at the University of Ibadan. The sera were obtained between September 2008 and February 2009. Of these 70 healthy individuals, 29 (41.4% consisting of 15 zoological garden workers (75.0%, 13 veterinarians (65.0% and 1 veterinary student (3.3% were immune to rabies virus (antibody titre >0.5 equivalent units per ml, while 41 (58.6% were not immune. The prevalence of rabies anti-glycoprotein antibody was higher within the older segment of the study population than among the younger veterinary students. Almost all those who had spent at least 10 years on the job had higher levels of rabies vaccination compliance and were immune. Our results indicated that there is low anti-rabies immunity among occupationally exposed individuals at the University of Ibadan. There is a need for a complete course of primary and booster vaccinations of professionals exposed to the rabies virus. The impact of these results on rabies control in Nigeria is discussed.

Helminth-infected patients with malaria: a low profile transmission hub?

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Nacher, Mathieu

2012-11-15

Eclipsed by the debates about malaria incidence and severity in individual patients, malaria transmission in helminth-infected persons has so far received very little attention. Studies in humans have shown increased malaria incidence and prevalence, and a trend for a reduction of symptoms in patients with malaria. This suggests that such patients could possibly be less likely to seek treatment thus carrying malaria parasites and their gametocytes for longer durations, therefore, being a greater potential source of transmission. In addition, in humans, a study showed increased gametocyte carriage, and in an animal model of helminth-malaria co-infection, there was increased malaria transmission. These elements converge towards the hypothesis that patients co-infected with worms and malaria may represent a hub of malaria transmission. The test of this hypothesis requires verifying, in different epidemiological settings, that helminth-infected patients have more gametocytes, that they have less symptomatic malaria and longer-lasting infections, and that they are more attractive for the vectors. The negative outcome in one setting of one of the above aspects does not necessarily mean that the other two aspects may suffice to increase transmission. If it is verified that patients co-infected by worms and malaria could be a transmission hub, this would be an interesting piece of strategic information in the context of the spread of anti-malarial resistance and the malaria eradication attempts.

Assessment of mercury exposure and malaria in a Brazilian Amazon riverine community

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Crompton, Peter; Ventura, Ana Maria; Souza, Jose Maria de; Santos, Elisabeth; Strickland, G. Thomas; Silbergeld, Ellen

2002-01-01

Small-scale gold mining in the Brazilian Amazon occurs in areas with high rates of malaria transmission. Amazonian populations can be exposed to mercury through direct contact with the mining process and/or through fish consumption. Because of data from experimental studies, we examined the potential for mercury to affect host response to malaria. A cross-sectional survey was done in Jacareacanga, a riverine community in Para state, in a region of intense alluvial gold mining. A sample of 205 persons was selected by cluster sampling from the total population of approximately 2000. A brief medical history and exam were conducted, malaria slides were obtained, and air samples were taken to measure mercury levels. The average hair mercury level was 8.6 μg/g, ranging from 0.3 to 83.2 μg/g. The most important predictors of elevated mercury levels were high fish consumption and low income. Although there was no prevalent malaria, the odds of reporting a past malaria infection was four times higher for those also reporting a history of working with mercury

Household cost of malaria overdiagnosis in rural Mozambique

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Armázio Luiz

2008-02-01

Full Text Available Abstract Background It is estimated that over 70% of patients with suspected malaria in sub-Saharan Africa, diagnose and manage their illness at home without referral to a formal health clinic. Of those patients who do attend a formal health clinic, malaria overdiagnosis rates are estimated to range between 30–70%. Methods This paper details an observational cohort study documenting the number and cost of repeat consultations as a result of malaria overdiagnosis at two health care providers in a rural district of Mozambique. 535 adults and children with a clinical diagnosis of malaria were enrolled and followed over a 21 day period to assess treatment regimen, symptoms, number and cost of repeat visits to health providers in patients misdiagnosed with malaria compared to those with confirmed malaria (determined by positive bloodfilm reading. Results Diagnosis based solely on clinical symptoms overdiagnosed 23% of children ( Conclusion Overdiagnosis of malaria results in a greater number of healthcare visits and associated cost for adult patients. Additionally, it is clear that the poorest individuals pay significantly more proportionally for their healthcare making it imperative that the treatment they receive is correct in order to prevent wastage of limited economic resources. Thus, investment in accurate malaria diagnosis and appropriate management at primary level is critical for improving health outcomes and reducing poverty.

Prevalence of respiratory symptoms and their correlation to pulmonary function abnormalities in individuals exposed to environmental pollution

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Khalid, G.H.; Ali, M.; Ahmed, J.; Abbas, M.N.

1999-01-01

To find out the prevalence of respiratory symptoms and their correlation to pulmonary function abnormalities in individuals exposed to polluted air, 438 workers, and their family members were studied at Thermal Power Station (TPS), Sheikhmanda (Quetta). Individuals with a stay of less than three years at TPS and patients with known chronic respiratory infections (tuberculosis and its squelae, bronchiectasis) were excluded from the study. Remaining 175 males (mean age 43.4 years) and 71 females (mean age 34.2 years) were divided into three groups A, B, C on the basis of their exposure time to polluted air per day during the three years. Each groups was further subdivided into smoker and non-smoker members. Prevalence of respiratory symptoms was significantly higher in the individuals exposed to polluted air as compared to non-exposed individuals (P<0.05). A strong positive correlation (r=0.91) exists between respiratory symptoms and respiratory function abnormalities in smoker groups; however, no definite correlation (r=0.06) was found between respiratory symptoms and respiratory function abnormalities in non-smoker groups. Function abnormalities was noted only in smoker groups and non-smokers of even maximally exposed group (group C) had almost no respiratory function abnormalities. (author)

High-frequency Audiometry Hearing on Monitoring of Individuals Exposed to Occupational Noise: A Systematic Review

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Antonioli, Cleonice Aparecida Silva

2015-12-01

Full Text Available Introduction The literature reports on high-frequency audiometry as one of the exams used on hearing monitoring of individuals exposed to high sound pressure in their work environment, due to the method́s greater sensitivity in early identification of hearing loss caused by noise. The frequencies that compose the exam are generally between 9 KHz and 20KHz, depending on the equipment. Objective This study aims to perform a retrospective and secondary systematic revision of publications on high-frequency audiometry on hearing monitoring of individuals exposed to occupational noise. Data Synthesis This systematic revision followed the methodology proposed in the Cochrane Handbook, focusing on the question: “Is High-frequency Audiometry more sensitive than Conventional Audiometry in the screening of early hearing loss individuals exposed to occupational noise?” The search was based on PubMed data, Base, Web of Science (Capes, Biblioteca Virtual em Saúde (BVS, and in the references cited in identified and selected articles. The search resulted in 6059 articles in total. Of these, only six studies were compatible with the criteria proposed in this study. Conclusion The performed meta-analysis does not definitively answer the study's proposed question. It indicates that the 16 KHz high frequency audiometry (HFA frequency is sensitive in early identification of hearing loss in the control group (medium difference (MD = 8.33, as well as the 4 KHz frequency (CA, this one being a little less expressive (MD = 5.72. Thus, others studies are necessary to confirm the HFA importance for the early screening of hearing loss on individuals exposed to noise at the workplace.

Helminth-infected patients with malaria: a low profile transmission hub?

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Nacher Mathieu

2012-11-01

Full Text Available Abstract Eclipsed by the debates about malaria incidence and severity in individual patients, malaria transmission in helminth-infected persons has so far received very little attention. Studies in humans have shown increased malaria incidence and prevalence, and a trend for a reduction of symptoms in patients with malaria. This suggests that such patients could possibly be less likely to seek treatment thus carrying malaria parasites and their gametocytes for longer durations, therefore, being a greater potential source of transmission. In addition, in humans, a study showed increased gametocyte carriage, and in an animal model of helminth-malaria co-infection, there was increased malaria transmission. These elements converge towards the hypothesis that patients co-infected with worms and malaria may represent a hub of malaria transmission. The test of this hypothesis requires verifying, in different epidemiological settings, that helminth-infected patients have more gametocytes, that they have less symptomatic malaria and longer-lasting infections, and that they are more attractive for the vectors. The negative outcome in one setting of one of the above aspects does not necessarily mean that the other two aspects may suffice to increase transmission. If it is verified that patients co-infected by worms and malaria could be a transmission hub, this would be an interesting piece of strategic information in the context of the spread of anti-malarial resistance and the malaria eradication attempts.

Malaria.

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Dupasquier, Isabelle

1989-01-01

Malaria, the greatest pandemia in the world, claims an estimated one million lives each year in Africa alone. While it may still be said that for the most part malaria is found in what is known as the world's poverty belt, cases are now frequently diagnosed in western countries. Due to resistant strains of malaria which have developed because of…

Malaria and protective behaviours: is there a malaria trap?

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Berthélemy, Jean-Claude; Thuilliez, Josselin; Doumbo, Ogobara; Gaudart, Jean

2013-06-13

In spite of massive efforts to generalize efficient prevention, such as insecticide-treated mosquito nets (ITN) or long-lasting insecticidal nets (LLINs), malaria remains prevalent in many countries and ITN/LLINs are still only used to a limited extent. This study proposes a new model for malaria economic analysis by combining economic epidemiology tools with the literature on poverty traps. A theoretical model of rational protective behaviour in response to malaria is designed, which includes endogenous externalities and disease characteristics. Survey data available for Uganda provide empirical support to the theory of prevalence-elastic protection behaviours, once endogeneity issues related to epidemiology and poverty are solved. Two important conclusions emerge from the model. First, agents increase their protective behaviour when malaria is more prevalent in a society. This is consistent with the literature on "prevalence-elastic behaviour". Second, a 'malaria trap' defined as the result of malaria reinforcing poverty while poverty reduces the ability to deal with malaria can theoretically exist and the conditions of existence of the malaria trap are identified. These results suggest the possible existence of malaria traps, which provides policy implications. Notably, providing ITN/LLINs at subsidized prices is not sufficient. To be efficient an ITN/LLINs dissemination campaigns should include incentive of the very poor for using ITN/LLINs.

A systematic review of transfusion-transmitted malaria in non-endemic areas.

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Verra, Federica; Angheben, Andrea; Martello, Elisa; Giorli, Giovanni; Perandin, Francesca; Bisoffi, Zeno

2018-01-16

Transfusion-transmitted malaria (TTM) is an accidental Plasmodium infection caused by whole blood or a blood component transfusion from a malaria infected donor to a recipient. Infected blood transfusions directly release malaria parasites in the recipient's bloodstream triggering the development of high risk complications, and potentially leading to a fatal outcome especially in individuals with no previous exposure to malaria or in immuno-compromised patients. A systematic review was conducted on TTM case reports in non-endemic areas to describe the epidemiological characteristics of blood donors and recipients. Relevant articles were retrieved from Pubmed, EMBASE, Scopus, and LILACS. From each selected study the following data were extracted: study area, gender and age of blood donor and recipient, blood component associated with TTM, Plasmodium species, malaria diagnostic method employed, blood donor screening method, incubation period between the infected transfusion and the onset of clinical symptoms in the recipient, time elapsed between the clinical symptoms and the diagnosis of malaria, infection outcome, country of origin of the blood donor and time of the last potential malaria exposure. Plasmodium species were detected in 100 TTM case reports with a different frequency: 45% Plasmodium falciparum, 30% Plasmodium malariae, 16% Plasmodium vivax, 4% Plasmodium ovale, 2% Plasmodium knowlesi, 1% mixed infection P. falciparum/P. malariae. The majority of fatal outcomes (11/45) was caused by P. falciparum whilst the other fatalities occurred in individuals infected by P. malariae (2/30) and P. ovale (1/4). However, non P. falciparum fatalities were not attributed directly to malaria. The incubation time for all Plasmodium species TTM case reports was longer than what expected in natural infections. This difference was statistically significant for P. malariae (p = 0.006). A longer incubation time in the recipient together with a chronic infection at low

About Malaria

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... Emergency Consultations, and General Public. Contact Us About Malaria Recommend on Facebook Tweet Share Compartir Malaria is ... from sub-Saharan Africa and South Asia. About Malaria Topics FAQs Frequently Asked Question, Incubation period, uncomplicated & ...

Spatial and temporal distribution of falciparum malaria in China

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Lin Hualiang

2009-06-01

Full Text Available Abstract Background Falciparum malaria is the most deadly among the four main types of human malaria. Although great success has been achieved since the launch of the National Malaria Control Programme in 1955, malaria remains a serious public health problem in China. This paper aimed to analyse the geographic distribution, demographic patterns and time trends of falciparum malaria in China. Methods The annual numbers of falciparum malaria cases during 1992–2003 and the individual case reports of each clinical falciparum malaria during 2004–2005 were extracted from communicable disease information systems in China Center for Diseases Control and Prevention. The annual number of cases and the annual incidence were mapped by matching them to corresponding province- and county-level administrative units in a geographic information system. The distribution of falciparum malaria by age, gender and origin of infection was analysed. Time-series analysis was conducted to investigate the relationship between the falciparum malaria in the endemic provinces and the imported falciparum malaria in non-endemic provinces. Results Falciparum malaria was endemic in two provinces of China during 2004–05. Imported malaria was reported in 26 non-endemic provinces. Annual incidence of falciparum malaria was mapped at county level in the two endemic provinces of China: Yunnan and Hainan. The sex ratio (male vs. female for the number of cases in Yunnan was 1.6 in the children of 0–15 years and it reached 5.7 in the adults over 15 years of age. The number of malaria cases in Yunnan was positively correlated with the imported malaria of concurrent months in the non-endemic provinces. Conclusion The endemic area of falciparum malaria in China has remained restricted to two provinces, Yunnan and Hainan. Stable transmission occurs in the bordering region of Yunnan and the hilly-forested south of Hainan. The age and gender distribution in the endemic area is

Asymptomatic Malaria and its Challenges in the Malaria Elimination Program in Iran: a Systematic Review

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Gholmreza Hassanpour

2017-06-01

Full Text Available Background: The ob­jective of this study was to find an appropriate approach to asymptomatic malaria in elimination setting through a systematic review.Methods: A broad search was conducted to find articles with the words ‘malaria’ in their titles and ‘asymptomatic’ or ‘submicroscopic’ in their texts, irrespective of the type of study conducted. The Cochrane, Medline/PubMed, and Scopus databases, as well as Google Scholar were systematically searched for English articles and reports and Iran’s databases- IranMedex, SID and Magiran were searched for Persian reports and articles, with no time limitation. The study was qualitatively summarized if it contained precise information on the role of asymptomatic malaria in the elimination phase.Results: Six articles were selected from the initial 2645 articles. The results all re-emphasize the significance of asymptomatic malaria in the elimination phase, and empha­size the significance of diagnostic tests of higher sensitivity to locate these patients and perform interventions to re­duce the asymptomatic parasitic reservoirs particularly in regions of low transmission. However, we may infer from the results that the current evidence cannot yet specify an accurate strategy on the role of asymptomatic malaria in the elimination phase.Conclusion: To eliminate malaria, alongside vector control, and treatment of symptomatic and asymptomatic pa­tients, active and inactive methods of case detection need to be employed. The precise monitoring of asymptomatic individuals and submicroscopic cases of malaria through molecular assays and valid serological methods, especially in regions where seasonal and low transmission exists can be very helpful at this phase.

STATUS HEMATOLOGI PENDERITA MALARIA SEREBRAL

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Nurhayati Nurhayati

2009-05-01

Full Text Available AbstrakMalaria masih merupakan masalah kesehatan masyarakat dunia. Berdasarkan klasifikasi klinis, malaria dibedakan atas malaria berat dan malaria tanpa komplikasi. Malaria serebral merupakan komplikasi terberat dari malaria falsiparum.Telah dilakukan penelitian seksi silang terhadap penderita malaria falciparum yang dirawat inap di Bangsal Penyakit Dalam RS. Perjan. Dr. M. Djamil Padang dari bulan Juni 2002 sampai Juni 2006. Pada penelitian ini didapatkan jumlah sampel sebanyak 60 orang, terdiri dari 16 orang penderita malaria serebral dan 44 orang penderita malaria tanpa komplikasi.Data penelitian menunjukan terdapat perbedaan bermakna nilai hematokrit (p<0,05 dan jumlah leukosit (p<0,05 antara penderita malaria serebral dengan penderita malaria tanpa komplikasi. Dan terdapat korelasi positif antara nilai hemoglobin dengan hematokrit (r=0,864; p<0,05 pada penderita malaria falsiparum.Kata kunci: malaria serebral, malaria tanpa komplikasi, malaria falsiparumAbstract Malaria is still a problem of health of world society. Based on the clinical classification, are distinguished on severe malaria and uncomplicated malaria. Cerebral malaria is the worst complication of falciparum malaria. Cross section of the research done at the Hospital Dr. M. Djamil Padang againts medical record of malaria patients who are hospitalized in the Internal Medicine from June 2002 until June 2004. In this study, a total sample of 60 people, consisting of 16 cerebral malaria and 44 uncomplicated malaria. Data showed there were significant differences for hematocrit values (p <0.05 and total leukocytes values (p <0.05 between cerebral malaria and uncomplicated malaria patients. There is a positive correlation between hemoglobin with hematocrit values (r = 0.864; p <0.05 of falciparum malaria patients. Keywords: cerebral malaria, uncomplicated malaria, falciparum malaria

Cross-sectional study defines difference in malaria morbidity in two Yanomami communities on Amazonian boundary between Brazil and Venezuela

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Teodardo José Marcano

2004-06-01

Full Text Available It is well established that immunity to malaria is short-lived and is maintained by the continuous contact with the parasite. We now show that the stable transmission of malaria in Yanomami Amerindian communities maintains a degree of immunity in the exposed population capable to reduce prevalence and morbidity of malaria. We examined 508 Yanomami Amerindians living along Orinoco (407 and Mucajaí (101 rivers, on the Venezuelan and Brazilian Amazon region, respectively. At Orinoco villages, malaria was hyperendemic and presented stable transmission, while at Mucajaí villages it was mesoendemic and showed unstable transmission. The frequency of Plasmodium vivax and P. falciparum was roughly comparable in Venezuelan and Brazilian communities. Malaria presented different profiles at Orinoco and Mucajaí villages. In the former communities, malaria showed a lower prevalence (16% x 40.6%, particularly among those over 10 years old (5.2% x 34.8%, a higher frequency of asymptomatic cases (38.5% x 4.9%, and a lower frequency of cases of severe malaria (9.2% x 36.5%. Orinoco villagers also showed a higher reactivity of the immune system, measured by the frequency of splenomegaly (72.4% x 29.7% and by the splenic index (71.4% over level 1 x 28.6, and higher prevalence (91.1% x 72.1% and mean titer (1243 x 62 of antiplasmodial IgG antibodies, as well as a higher prevalence (77.4% x 24.7% and mean titer (120 x 35 of antiplasmodial IgM antibodies. Our findings show that in isolated Yanomami communities the stability of malaria transmission, and the consequent continuous activation of the immune system of the exposed population, leads to the reduction of malaria prevalence and morbidity.

Cross-sectional study defines difference in malaria morbidity in two Yanomami communities on Amazonian boundary between Brazil and Venezuela.

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Marcano, Teodardo José; Morgado, Anastácio; Tosta, Carlos Eduardo; Coura, José Rodrigues

2004-06-01

It is well established that immunity to malaria is short-lived and is maintained by the continuous contact with the parasite. We now show that the stable transmission of malaria in Yanomami Amerindian communities maintains a degree of immunity in the exposed population capable to reduce prevalence and morbidity of malaria. We examined 508 Yanomami Amerindians living along Orinoco (407) and Mucajaí (101) rivers, on the Venezuelan and Brazilian Amazon region, respectively. At Orinoco villages, malaria was hyperendemic and presented stable transmission, while at Mucajaí villages it was mesoendemic and showed unstable transmission. The frequency of Plasmodium vivax and P. falciparum was roughly comparable in Venezuelan and Brazilian communities. Malaria presented different profiles at Orinoco and Mucajaí villages. In the former communities, malaria showed a lower prevalence (16% x 40.6%), particularly among those over 10 years old (5.2% x 34.8%), a higher frequency of asymptomatic cases (38.5% x 4.9%), and a lower frequency of cases of severe malaria (9.2% x 36.5%). Orinoco villagers also showed a higher reactivity of the immune system, measured by the frequency of splenomegaly (72.4% x 29.7%) and by the splenic index (71.4% over level 1 x 28.6), and higher prevalence (91.1% x 72.1%) and mean titer (1243 x 62) of antiplasmodial IgG antibodies, as well as a higher prevalence (77.4% x 24.7%) and mean titer (120 x 35) of antiplasmodial IgM antibodies. Our findings show that in isolated Yanomami communities the stability of malaria transmission, and the consequent continuous activation of the immune system of the exposed population, leads to the reduction of malaria prevalence and morbidity.

Helminths and malaria co-infections are associated with elevated serum IgE

DEFF Research Database (Denmark)

Mulu, Andargachew; Kassu, Afework; Legesse, Mengistu

2014-01-01

BACKGROUND: Both helminth and malaria infections result in a highly polarized immune response characterized by IgE production. This study aimed to investigate the total serum IgE profile in vivo as a measure of Th2 immune response in malaria patients with and without helminth co-infection. METHODS......: A cross sectional observational study composed of microscopically confirmed malaria positive (N = 197) and malaria negative (N = 216) apparently healthy controls with and without helminth infection was conducted at Wondo Genet Health Center, Southern Ethiopia. A pre-designed structured format was utilized...... to collect socio-demographic and clinical data of the subjects. Detection and quantification of helminths, malaria parasites and determination of serum IgE levels were carried out following standard procedures. RESULTS: Irrespective of helminth infection, individuals infected by malaria showed significantly...

Asymptomatic and sub-microscopic malaria infection in Kayah State, eastern Myanmar.

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Zaw, Myo Thiha; Thant, Myo; Hlaing, Tin Maung; Aung, Naing Zin; Thu, Min; Phumchuea, Kanit; Phusri, Kanokwan; Saeseu, Teerawat; Yorsaeng, Ritthideach; Nguitragool, Wang; Felger, Ingrid; Kaewkungwal, Jaranit; Cui, Liwang; Sattabongkot, Jetsumon

2017-04-04

Myanmar has the heaviest burden of malaria in the Greater Mekong Sub-region. Asymptomatic Plasmodium spp. infections are common in this region and may represent an important reservoir of transmission that must be targeted for malaria elimination. A mass blood survey was conducted among 485 individuals from six villages in Kayah State, an area of endemic but low transmission malaria in eastern Myanmar. Malaria infection was screened by rapid diagnostic test (RDT), light microscopy and real-time polymerase chain reaction (PCR), and its association with demographic factors was explored. The prevalence of asymptomatic Plasmodium spp. infection was 2.3% (11/485) by real-time PCR. Plasmodium vivax accounted for 72.7% (8/11) and Plasmodium falciparum for 27.3% (3/11) of infections. Men were at greater risk of infection by Plasmodium spp. than women. Individuals who worked as farmers or wood and bamboo cutters had an increased risk of infection. A combination of RDT, light microscopy and PCR diagnostics were used to identify asymptomatic malaria infection, providing additional information on asymptomatic cases in addition to the routine statistics on symptomatic cases, so as to determine the true burden of disease in the area. Such information and risk factors can improve malaria risk stratification and guide decision-makers towards better design and delivery of targeted interventions in small villages, representative of Kayah State.

Malaria risk factors and care-seeking behaviour within the private sector among high-risk populations in Vietnam: a qualitative study.

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Chen, Ingrid; Thanh, Huong Ngo Thi; Lover, Andrew; Thao, Phung Thi; Luu, Tang Viet; Thang, Hoang Nghia; Thang, Ngo Duc; Neukom, Josselyn; Bennett, Adam

2017-10-16

Vietnam has successfully reduced malaria incidence by more than 90% over the past 10 years, and is now preparing for malaria elimination. However, the remaining malaria burden resides in individuals that are hardest to reach, in highly remote areas, where many malaria cases are treated through the informal private sector and are not reported to public health systems. This qualitative study aimed to contextualize and characterize the role of private providers, care-seeking behaviour of individuals at high risk of malaria, as well as risk factors that should be addressed through malaria elimination programmes in Vietnam. Semi-structured qualitative interviews were conducted with 11 key informants in Hanoi, 30 providers, 9 potential patients, and 11 individuals at risk of malaria in Binh Phuoc and Kon Tum provinces. Audio recorded interviews were transcribed and uploaded to Atlas TI™, themes were identified, from which programmatic implications and recommendations were synthesized. Qualitative interviews revealed that efforts for malaria elimination in Vietnam should concentrate on reaching highest-risk populations in remote areas as well their care providers, in particular private pharmacies, private clinics, and grocery stores. Among these private providers, diagnosis is currently based on symptoms, leaving unconfirmed cases that are not reported to public health surveillance systems. Among at-risk individuals, knowledge of malaria was limited, and individuals reported not taking full courses of treatment, a practice that threatens selection for drug resistance. Access to insecticide-treated hammock nets, a potentially important preventive measure for settings with outdoor biting Anopheles vectors, was also limited. Malaria elimination efforts in Vietnam can be accelerated by targeting improved treatment, diagnosis, and reporting practices to private pharmacies, private clinics, and grocery stores. Programmes should also seek to increase awareness and

White Blood Cell Counts and Malaria

National Research Council Canada - National Science Library

McKenzie, F. E; Prudhomme, Wendy A; Magill, Alan J; Forney, J. R; Permpanich, Barnyen; Lucas, Carmen; Gasser, Jr., Robert A; Wongsrichanalai, Chansuda

2005-01-01

White blood cells (WBCs) were counted in 4697 individuals who presented to outpatient malaria clinics in Maesod, Tak Province, Thailand, and Iquitos, Peru, between 28 May and 28 August 1998 and between 17 May and 9 July 1999...

Controlled Human Malaria Infection: Applications, Advances, and Challenges.

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Stanisic, Danielle I; McCarthy, James S; Good, Michael F

2018-01-01

Controlled human malaria infection (CHMI) entails deliberate infection with malaria parasites either by mosquito bite or by direct injection of sporozoites or parasitized erythrocytes. When required, the resulting blood-stage infection is curtailed by the administration of antimalarial drugs. Inducing a malaria infection via inoculation with infected blood was first used as a treatment (malariotherapy) for neurosyphilis in Europe and the United States in the early 1900s. More recently, CHMI has been applied to the fields of malaria vaccine and drug development, where it is used to evaluate products in well-controlled early-phase proof-of-concept clinical studies, thus facilitating progression of only the most promising candidates for further evaluation in areas where malaria is endemic. Controlled infections have also been used to immunize against malaria infection. Historically, CHMI studies have been restricted by the need for access to insectaries housing infected mosquitoes or suitable malaria-infected individuals. Evaluation of vaccine and drug candidates has been constrained in these studies by the availability of a limited number of Plasmodium falciparum isolates. Recent advances have included cryopreservation of sporozoites, the manufacture of well-characterized and genetically distinct cultured malaria cell banks for blood-stage infection, and the availability of Plasmodium vivax -specific reagents. These advances will help to accelerate malaria vaccine and drug development by making the reagents for CHMI more widely accessible and also enabling a more rigorous evaluation with multiple parasite strains and species. Here we discuss the different applications of CHMI, recent advances in the use of CHMI, and ongoing challenges for consideration. Copyright © 2017 American Society for Microbiology.

A world malaria map: Plasmodium falciparum endemicity in 2007.

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Simon I Hay

2009-03-01

Full Text Available Efficient allocation of resources to intervene against malaria requires a detailed understanding of the contemporary spatial distribution of malaria risk. It is exactly 40 y since the last global map of malaria endemicity was published. This paper describes the generation of a new world map of Plasmodium falciparum malaria endemicity for the year 2007.A total of 8,938 P. falciparum parasite rate (PfPR surveys were identified using a variety of exhaustive search strategies. Of these, 7,953 passed strict data fidelity tests for inclusion into a global database of PfPR data, age-standardized to 2-10 y for endemicity mapping. A model-based geostatistical procedure was used to create a continuous surface of malaria endemicity within previously defined stable spatial limits of P. falciparum transmission. These procedures were implemented within a Bayesian statistical framework so that the uncertainty of these predictions could be evaluated robustly. The uncertainty was expressed as the probability of predicting correctly one of three endemicity classes; previously stratified to be an informative guide for malaria control. Population at risk estimates, adjusted for the transmission modifying effects of urbanization in Africa, were then derived with reference to human population surfaces in 2007. Of the 1.38 billion people at risk of stable P. falciparum malaria, 0.69 billion were found in Central and South East Asia (CSE Asia, 0.66 billion in Africa, Yemen, and Saudi Arabia (Africa+, and 0.04 billion in the Americas. All those exposed to stable risk in the Americas were in the lowest endemicity class (PfPR2-10 5 to or = 40% areas. High endemicity was widespread in the Africa+ region, where 0.35 billion people are at this level of risk. Most of the rest live at intermediate risk (0.20 billion, with a smaller number (0.11 billion at low stable risk.High levels of P. falciparum malaria endemicity are common in Africa. Uniformly low endemic levels are

A world malaria map: Plasmodium falciparum endemicity in 2007.

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Hay, Simon I; Guerra, Carlos A; Gething, Peter W; Patil, Anand P; Tatem, Andrew J; Noor, Abdisalan M; Kabaria, Caroline W; Manh, Bui H; Elyazar, Iqbal R F; Brooker, Simon; Smith, David L; Moyeed, Rana A; Snow, Robert W

2009-03-24

Efficient allocation of resources to intervene against malaria requires a detailed understanding of the contemporary spatial distribution of malaria risk. It is exactly 40 y since the last global map of malaria endemicity was published. This paper describes the generation of a new world map of Plasmodium falciparum malaria endemicity for the year 2007. A total of 8,938 P. falciparum parasite rate (PfPR) surveys were identified using a variety of exhaustive search strategies. Of these, 7,953 passed strict data fidelity tests for inclusion into a global database of PfPR data, age-standardized to 2-10 y for endemicity mapping. A model-based geostatistical procedure was used to create a continuous surface of malaria endemicity within previously defined stable spatial limits of P. falciparum transmission. These procedures were implemented within a Bayesian statistical framework so that the uncertainty of these predictions could be evaluated robustly. The uncertainty was expressed as the probability of predicting correctly one of three endemicity classes; previously stratified to be an informative guide for malaria control. Population at risk estimates, adjusted for the transmission modifying effects of urbanization in Africa, were then derived with reference to human population surfaces in 2007. Of the 1.38 billion people at risk of stable P. falciparum malaria, 0.69 billion were found in Central and South East Asia (CSE Asia), 0.66 billion in Africa, Yemen, and Saudi Arabia (Africa+), and 0.04 billion in the Americas. All those exposed to stable risk in the Americas were in the lowest endemicity class (PfPR2-10 5 to or = 40%) areas. High endemicity was widespread in the Africa+ region, where 0.35 billion people are at this level of risk. Most of the rest live at intermediate risk (0.20 billion), with a smaller number (0.11 billion) at low stable risk. High levels of P. falciparum malaria endemicity are common in Africa. Uniformly low endemic levels are found in the

Malaria and World War II: German malaria experiments 1939-45.

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Eckart, W U; Vondra, H

2000-06-01

The epidemiological and pharmacological fight against malaria and German malaria research during the Nazi dictatorship were completely under the spell of war. The Oberkommando des Heeres (German supreme command of the army) suffered the bitter experience of unexpected high losses caused by malaria especially at the Greek front (Metaxes line) but also in southern Russia and in the Ukraine. Hastily raised anti-malaria units tried to teach soldiers how to use the synthetic malaria drugs (Plasmochine, Atebrine) properly. Overdoses of these drugs were numerous during the first half of the war whereas in the second half it soon became clear that it would not be possible to support the army due to insufficient quantities of plasmochine and atebrine. During both running fights and troop withdrawals at all southern and southeastern fronts there was hardly any malaria prophylaxis or treatment. After war and captivity many soldiers returned home to endure heavy malaria attacks. In German industrial (Bayer, IG-Farben) and military malaria laboratories of the Heeres-Sanitäts-Akademie (Army Medical Academy) the situation was characterised by a hasty search for proper dosages of anti-malaria drugs, adequate mechanical and chemical prophylaxis (Petroleum, DDT, and other insecticides) as well as an anti-malaria vaccine. Most importantly, large scale research for proper atebrine and plasmochine dosages was conducted in German concentration camps and mental homes. In Dachau Professor Claus Schilling tested synthetic malaria drugs and injected helpless prisoners with high and sometimes lethal doses. Since the 1920s he had been furiously looking for an anti-malaria vaccine in Italian mental homes and from 1939 he continued his experiments in Dachau. Similar experiments were also performed in Buchenwald and in a psychiatric clinic in Thuringia, where Professor Gerhard Rose tested malaria drugs with mentally ill Russian prisoners of war. Schilling was put to death for his criminal

Submicroscopic malaria parasite carriage: how reproducible are polymerase chain reaction-based methods?

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Daniela Camargos Costa

2014-02-01

Full Text Available The polymerase chain reaction (PCR-based methods for the diagnosis of malaria infection are expected to accurately identify submicroscopic parasite carriers. Although a significant number of PCR protocols have been described, few studies have addressed the performance of PCR amplification in cases of field samples with submicroscopic malaria infection. Here, the reproducibility of two well-established PCR protocols (nested-PCR and real-time PCR for the Plasmodium 18 small subunit rRNA gene were evaluated in a panel of 34 blood field samples from individuals that are potential reservoirs of malaria infection, but were negative for malaria by optical microscopy. Regardless of the PCR protocol, a large variation between the PCR replicates was observed, leading to alternating positive and negative results in 38% (13 out of 34 of the samples. These findings were quite different from those obtained from the microscopy-positive patients or the unexposed individuals; the diagnosis of these individuals could be confirmed based on the high reproducibility and specificity of the PCR-based protocols. The limitation of PCR amplification was restricted to the field samples with very low levels of parasitaemia because titrations of the DNA templates were able to detect < 3 parasites/µL in the blood. In conclusion, conventional PCR protocols require careful interpretation in cases of submicroscopic malaria infection, as inconsistent and false-negative results can occur.

Out of the net: An agent-based model to study human movements influence on local-scale malaria transmission.

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Francesco Pizzitutti

Full Text Available Though malaria control initiatives have markedly reduced malaria prevalence in recent decades, global eradication is far from actuality. Recent studies show that environmental and social heterogeneities in low-transmission settings have an increased weight in shaping malaria micro-epidemiology. New integrated and more localized control strategies should be developed and tested. Here we present a set of agent-based models designed to study the influence of local scale human movements on local scale malaria transmission in a typical Amazon environment, where malaria is transmission is low and strongly connected with seasonal riverine flooding. The agent-based simulations show that the overall malaria incidence is essentially not influenced by local scale human movements. In contrast, the locations of malaria high risk spatial hotspots heavily depend on human movements because simulated malaria hotspots are mainly centered on farms, were laborers work during the day. The agent-based models are then used to test the effectiveness of two different malaria control strategies both designed to reduce local scale malaria incidence by targeting hotspots. The first control scenario consists in treat against mosquito bites people that, during the simulation, enter at least once inside hotspots revealed considering the actual sites where human individuals were infected. The second scenario involves the treatment of people entering in hotspots calculated assuming that the infection sites of every infected individual is located in the household where the individual lives. Simulations show that both considered scenarios perform better in controlling malaria than a randomized treatment, although targeting household hotspots shows slightly better performance.

Out of the net: An agent-based model to study human movements influence on local-scale malaria transmission.

Science.gov (United States)

Pizzitutti, Francesco; Pan, William; Feingold, Beth; Zaitchik, Ben; Álvarez, Carlos A; Mena, Carlos F

2018-01-01

Though malaria control initiatives have markedly reduced malaria prevalence in recent decades, global eradication is far from actuality. Recent studies show that environmental and social heterogeneities in low-transmission settings have an increased weight in shaping malaria micro-epidemiology. New integrated and more localized control strategies should be developed and tested. Here we present a set of agent-based models designed to study the influence of local scale human movements on local scale malaria transmission in a typical Amazon environment, where malaria is transmission is low and strongly connected with seasonal riverine flooding. The agent-based simulations show that the overall malaria incidence is essentially not influenced by local scale human movements. In contrast, the locations of malaria high risk spatial hotspots heavily depend on human movements because simulated malaria hotspots are mainly centered on farms, were laborers work during the day. The agent-based models are then used to test the effectiveness of two different malaria control strategies both designed to reduce local scale malaria incidence by targeting hotspots. The first control scenario consists in treat against mosquito bites people that, during the simulation, enter at least once inside hotspots revealed considering the actual sites where human individuals were infected. The second scenario involves the treatment of people entering in hotspots calculated assuming that the infection sites of every infected individual is located in the household where the individual lives. Simulations show that both considered scenarios perform better in controlling malaria than a randomized treatment, although targeting household hotspots shows slightly better performance.

Pulmonary manifestations of malaria : recognition and management.

Science.gov (United States)

Taylor, Walter R J; Cañon, Viviam; White, Nicholas J

2006-01-01

Lung involvement in malaria has been recognized for more than 200 hundred years, yet our knowledge of its pathogenesis and management is limited. Pulmonary edema is the most severe form of lung involvement. Increased alveolar capillary permeability leading to intravascular fluid loss into the lungs is the main pathophysiologic mechanism. This defines malaria as another cause of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS).Pulmonary edema has been described most often in non-immune individuals with Plasmodium falciparum infections as part of a severe systemic illness or as the main feature of acute malaria. P.vivax and P.ovale have also rarely caused pulmonary edema.Clinically, patients usually present with acute breathlessness that can rapidly progress to respiratory failure either at disease presentation or, interestingly, after treatment when clinical improvement is taking place and the parasitemia is falling. Pregnant women are particularly prone to developing pulmonary edema. Optimal management of malaria-induced ALI/ARDS includes early recognition and diagnosis. Malaria must always be suspected in a returning traveler or a visitor from a malaria-endemic country with an acute febrile illness. Slide microscopy and/or the use of rapid antigen tests are standard diagnostic tools. Malaria must be treated with effective drugs, but current choices are few: e.g. parenteral artemisinins, intravenous quinine or quinidine (in the US only). A recent trial in adults has shown that intravenous artesunate reduces severe malaria mortality by a third compared with adults treated with intravenous quinine. Respiratory compromise should be managed on its merits and may require mechanical ventilation.Patients should be managed in an intensive care unit and particular attention should be paid to the energetic management of other severe malaria complications, notably coma and acute renal failure. ALI/ARDS may also be related to a coincidental bacterial

Malaria og graviditet

DEFF Research Database (Denmark)

Hoffmann, A L; Rønn, A M; Langhoff-Roos, J

1992-01-01

In regions where malaria is endemism, the disease is a recognised cause of complications of pregnancy such as spontaneous abortion, premature delivery, intrauterine growth retardation and foetal death. Malaria is seldom seen in pregnant women in Denmark but, during the past two years, the authors...... the patients but also their practitioners were unaware that malaria can occur several years after exposure. Three out of the four patients had employed malaria prophylaxis. As resistance to malarial prophylactics in current use is increasing steadily, chemoprophylaxis should be supplemented by mechanical...... protection against malaria and insect repellents. As a rule, malaria is treated with chloroquine. In cases of Falciparum malaria in whom chloroquine resistance is suspected, treatment with mefloquine may be employed although this should only be employed in cases of dire necessity in pregnant patients during...

The fate of chromosomal aberrations in 137Cs-exposed individuals in the Goiania radiation accident

International Nuclear Information System (INIS)

Ramalho, A.T.; Nascimento, A.C.

1991-01-01

Following the Goiania radiation accident, lymphocytes from 110 exposed or potentially exposed individuals were analyzed for the frequencies of chromosomal aberrations (dicentrics and centric rings) to estimate absorbed radiation dose. Dose estimates for 21 subjects exceeded 1.0 Gy, and for eight subjects they exceeded 4.0 Gy. Four of the subjects died. After the emergency period, a cytogenetic follow-up of 10 of the highest exposed patients was started. The results suggest that the average disappearance half-time of lymphocytes containing dicentric and centric rings was 130 d, which is shorter than the usually accepted value of 3 y reported in the literature

Cytometric quantification of singlet oxygen in the human malaria parasite Plasmodium falciparum

NARCIS (Netherlands)

Butzloff, Sabine; Groves, Matthew R; Wrenger, Carsten; Müller, Ingrid B

The malaria parasite Plasmodium falciparum proliferates within human erythrocytes and is thereby exposed to a variety of reactive oxygen species (ROS) such as hydrogen peroxide, hydroxyl radical, superoxide anion, and highly reactive singlet oxygen ((1)O(2)). While most ROS are already well studied

Humoral immune response to Plasmodium falciparum vaccine candidate GMZ2 and its components in populations naturally exposed to seasonal malaria in Ethiopia

DEFF Research Database (Denmark)

Mamo, Hassen; Esen, Meral; Ajua, Anthony

2013-01-01

for malaria infection microscopically and by the rapid diagnostic test (RDT). Sera were tested by using enzyme-linked immunosorbent assay (ELISA) for total immunoglobulin (Ig) G against P. falciparum blood-stage vaccine candidate GMZ2 and its subunits (Glutamate-rich protein (GLURP-R0), merozoite surface...... transmission in the two localities and/or genetic differences between the two populations in their response to the antigens. In both study sites, IgG subclass levels to GLURP-R0 were significantly higher than that to MSP3 for all corresponding subclasses in most individuals, indicating the higher relative...

Prevalence of Malaria Plasmodium in Abeokuta, Nigeria

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Okonko, I. O.

2009-01-01

Full Text Available This study reports the prevalence of malaria caused by plasmodium between genders in Abeokuta, the capital city of Ogun State located in the forest zone of southwestern Nigeria between January 2002 and December 2004. Blood film examination for malaria parasites in 708 patients; 366 males and 342 females. Microscopic examination of thick films techniques was employed for this study. Of the 708 (100% patients examined, 577 (81.5% were Plasmodium-positive. A high malaria parasite prevalence rate of 81.5% was noted in this study. Female subjects were more infected (42.4% than males (41.9% however, there was no significant difference in the sex of the subjects studied (p=0.05. A high malaria parasite prevalence rate of 86.9% was noted in samples collected in year 2003 than in other years studied. There was significant difference in the years under study (p=0.05. This study shows that a good percentage of people were infested by malaria Plasmodium. This could be attributed to lack of adequate accommodation and poor sanitary conditions in the area under study. Although several efforts have been made to effectively control the high incidence of malaria in Nigeria, these have been largely unsuccessful due to a number of reasons such as irrigated urban agriculture which can be the malaria vector’s breeding ground in the city, stagnant gutters and swamps in our environment where mosquitoes breed in millions, and lack of political will and commitment of the government in its disease management program, low awareness of the magnitude of malaria problem, poor health practices by individuals and communities and resistance to drugs. Therefore, future interventions in Nigeria should be directed toward controlling malaria in the context of a moderate transmission setting; thus, large-scale distribution of insecticide-treated nets or widespread use of indoor residual spraying may be less cost-effective than enhanced surveillance with effective case management or

Leukemia incidence among individuals exposed in utero, children of atomic bomb survivors, and their controls; Hiroshima and Nagasaki, 1945-79

International Nuclear Information System (INIS)

Ishimaru, Toranosuke; Ichimaru, Michito; Mikami, Motoko.

1982-03-01

The incidence of leukemia has been analyzed in relation to the fetal dose of individuals exposed in utero, and the parental gonadal dose of individuals born to atomic bomb survivors and controls in the two fixed RERF cohorts. Among 3,636 in utero exposed children and controls, 3 leukemia cases have been identified through 1979. No excess risk of leukemia for in utero exposed children is apparent. For children born to exposed parents and controls, 36 leukemia cases have been identified in the years 1946-79 among 50,689 study subjects where the parental gonadal dose is available. Again, no excess risk of leukemia exists. (author)

Natural disaster-induced environmental migration from the Indian subcontinent resulting in malaria outbreak in Greece

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Mavrouli, Maria; Mavroulis, Spyridon; Piperaki, Evangelia-Theofano; Hadjichristodoulou, Christos; Tsakris, Athanassios

2017-04-01

Extreme hydrometeorological disasters such as floods and hurricanes can severely damage human life, natural and built environment and economic development. Consequently, they can result in environmental migration (EM). In case of infectious disease (ID) outbreaks during the post-disaster period and subsequent EM, environmental refugees from endemic regions serve as ID carriers to their new residence sites altering the spatial ID distribution and incidence. The continuous massive influx of environmental refugees from malaria endemic regions to non-endemic ones can build up a parasite reservoir among naive host populations. Initially, serum specimens were collected in 2012 from asymptomatic individuals, 298 Greeks and 721 immigrants residing in areas of documented local malaria transmission in Laconia (Southern Peloponnese) and in Eastern Attica, Greece. Sera were tested for antibodies against Plasmodium vivax and P. falciparum using the Malaria-Ab ELISA (IBL International GMBH, Hamburg, Germany). Taking into account that Greece has been declared malaria free by the WHO since 1974, we conducted an extensive and systematic literature review related to natural disasters leading among others to increased malaria risk in Indian Subcontinent and respective forced EM in order to detect relative possible causes of reintroduction and localized outbreaks of malaria in Greece. Regarding the country of origin, information was available for 685 (95%) of the 721 immigrants. Of the 678 immigrants from Indian Subcontinent, 627 (92.5%) originated from Pakistan, 24 (3.53%) Afghanistan, 24 (3.53%) India and 3 (0.44%) Bangladesh. Of the 721 immigrants, 582 and 124 resided in Laconia and Eastern Attica respectively. Seventy-one immigrants residing in Laconia and 14 in Eastern Attica were positive for antimalarial antibodies, while none of the 298 Greeks residing in Laconia (N=248) and Attica (N=50) was found positive. Based on already published scientific data, Pakistan has been exposed

Coexistence of Malaria and Thalassemia in Malaria Endemic Areas of Thailand

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Kuesap, Jiraporn; Chaijaroenkul, W.; Rungsihirunrat, K.; Pongjantharasatien, K.; Na-Bangchang, Kesara

2015-01-01

Hemoglobinopathy and malaria are commonly found worldwide particularly in malaria endemic areas. Thalassemia, the alteration of globin chain synthesis, has been reported to confer resistance against malaria. The prevalence of thalassemia was investigated in 101 malaria patients with Plasmodium falciparum and Plasmodium vivax along the Thai-Myanmar border to examine protective effect of thalassemia against severe malaria. Hemoglobin typing was performed using low pressure liquid chromatography (LPLC) and α-thalassemia was confirmed by multiplex PCR. Five types of thalassemia were observed in malaria patients. The 2 major types of thalassemia were Hb E (18.8%) and α-thalassemia-2 (11.9%). There was no association between thalassemia hemoglobinopathy and malaria parasitemia, an indicator of malaria disease severity. Thalassemia had no significant association with P. vivax infection, but the parasitemia in patients with coexistence of P. vivax and thalassemia was about 2-3 times lower than those with coexistence of P. falciparum and thalassemia and malaria without thalassemia. Furthermore, the parasitemia of P. vivax in patients with coexistence of Hb E showed lower value than coexistence with other types of thalassemia and malaria without coexistence. Parasitemia, hemoglobin, and hematocrit values in patients with coexistence of thalassemia other than Hb E were significantly lower than those without coexistence of thalassemia. Furthermore, parasitemia with coexistence of Hb E were 2 times lower than those with coexistence of thalassemia other than Hb E. In conclusion, the results may, at least in part, support the protective effect of thalassemia on the development of hyperparasitemia and severe anemia in malaria patients. PMID:26174819

Application of molecular methods for monitoring transmission stages of malaria parasites

International Nuclear Information System (INIS)

Babiker, Hamza A; Schneider, Petra

2008-01-01

Recent technical advances in malaria research have allowed specific detection of mRNA of genes that are expressed exclusively in sexual stages (gametocytes) of malaria parasites. The specificity and sensitivity of these techniques were validated on cultured laboratory clones of both human malaria parasites (Plasmodium falciparum) and rodent parasites (P. chabaudi). More recently, quantitative molecular techniques have been developed to quantify these sexual stages and used to monitor gametocyte dynamics and their transmission to mosquitoes. Molecular techniques showed that the infectious reservoir for malaria is larger than expected from previous microscopic studies; individual parasite genotypes within an infection can simultaneously produce infectious gametocytes; gametocyte production can be sustained for several months, and is modulated by environmental factors. The above techniques have empowered approaches for in-depth analysis of the biology of the transmission stages of the parasite and epidemiology of malaria transmission

Deviance and resistance: Malaria elimination in the greater Mekong subregion.

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Lyttleton, Chris

2016-02-01

Malaria elimination rather than control is increasingly globally endorsed, requiring new approaches wherein success is not measured by timely treatment of presenting cases but eradicating all presence of infection. This shift has gained urgency as resistance to artemisinin-combination therapies spreads in the Greater Mekong Sub-region (GMS) posing a threat to global health security. In the GMS, endemic malaria persists in forested border areas and elimination will require calibrated approaches to remove remaining pockets of residual infection. A new public health strategy called 'positive deviance' is being used to improve health promotion and community outreach in some of these zones. However, outbreaks sparked by alternative understandings of appropriate behaviour expose the unpredictable nature of 'border malaria' and difficulties eradication faces. Using a recent spike in infections allegedly linked to luxury timber trade in Thai borderlands, this article suggests that opportunities for market engagement can cause people to see 'deviance' as a means to material advancement in ways that increase disease vulnerability. A malaria outbreak in Ubon Ratchathani was investigated during two-week field-visit in November 2014 as part of longer project researching border malaria in Thai provinces. Qualitative data were collected in four villages in Ubon's three most-affected districts. Discussions with villagers focused primarily on changing livelihoods, experience with malaria, and rosewood cutting. Informants included ten men and two women who had recently overnighted in the nearby forest. Data from health officials and villagers are used to frame Ubon's rise in malaria transmission within moral and behavioural responses to expanding commodity supply-chains. The article argues that elimination strategies in the GMS must contend with volatile outbreaks among border populations wherein 'infectiousness' and 'resistance' are not simply pathogen characteristics but also

An ecosystem approach to malaria control in an urban setting

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Carrasquilla Gabriel

2001-01-01

Full Text Available We conducted a research project aimed at strengthening local government and the community for a sustainable malaria control strategy. The project began with a baseline diagnosis of malaria prevalence, a KAP survey, entomology, and health services delivery, after which an epidemiological study was performed to identify risk factors associated with malaria, thereafter used to plan intervention measures. A program evaluation was conducted five years later. By using an ecosystem approach to reanalyze data, this paper discusses how malaria arises from a complex interaction of cultural, economic, ecological, social, and individual factors. Intervention measures require an intersectorial and transdisciplinary approach that does not exist at the moment. Health sector leadership is limited, and there is no true community participation. Implications for research, including the use of qualitative and quantitative methods, study design, and complexity of data analysis are discussed. Finally, implications for malaria control are discussed, stressing the differences between the ecosystem and integrated disease control approaches.

Improving malaria knowledge and practices in rural Myanmar through a village health worker intervention: a cross-sectional study.

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Lwin, Moh Moh; Sudhinaraset, May; San, Aung Kyaw; Aung, Tin

2014-01-04

Since 2008 the Sun Primary Health (SPH) franchise programme has networked and branded community health workers in rural Myanmar to provide high quality malaria information and treatment. The purpose of this paper is to compare the malaria knowledge level and health practices of individuals in SPH intervention areas to individuals without SPH intervention This study uses data from a cross-sectional household survey of 1,040 individuals living in eight rural townships to compare the knowledge level of individuals in SPH intervention areas to individuals without SPH intervention. This study found that the presence of a SPH provider in the community is associated with increased malaria knowledge and higher likelihood of going to trained providers for fevers. Furthermore, the study found a dose-response, where the longer the duration of the programme in a community, the greater the community knowledge level. The study suggests that community health workers might have significant impact on malaria-related mortality and morbidity in rural Myanmar.

Simulation of malaria epidemiology and control in the highlands of western Kenya

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Stuckey Erin M

2012-10-01

Full Text Available Abstract Background Models of Plasmodium falciparum malaria epidemiology that provide realistic quantitative predictions of likely epidemiological outcomes of existing vector control strategies have the potential to assist in planning for the control and elimination of malaria. This work investigates the applicability of mathematical modelling of malaria transmission dynamics in Rachuonyo South, a district with low, unstable transmission in the highlands of western Kenya. Methods Individual-based stochastic simulation models of malaria in humans and a deterministic model of malaria in mosquitoes as part of the OpenMalaria platform were parameterized to create a scenario for the study area based on data from ongoing field studies and available literature. The scenario was simulated for a period of two years with a population of 10,000 individuals and validated against malaria survey data from Rachuonyo South. Simulations were repeated with multiple random seeds and an ensemble of 14 model variants to address stochasticity and model uncertainty. A one-dimensional sensitivity analysis was conducted to address parameter uncertainty. Results The scenario was able to reproduce the seasonal pattern of the entomological inoculation rate (EIR and patent infections observed in an all-age cohort of individuals sampled monthly for one year. Using an EIR estimated from serology to parameterize the scenario resulted in a closer fit to parasite prevalence than an EIR estimated using entomological methods. The scenario parameterization was most sensitive to changes in the timing and effectiveness of indoor residual spraying (IRS and the method used to detect P. falciparum in humans. It was less sensitive than expected to changes in vector biting behaviour and climatic patterns. Conclusions The OpenMalaria model of P. falciparum transmission can be used to simulate the impact of different combinations of current and potential control interventions to help plan

Potential public health impact of RTS,S malaria candidate vaccine in sub-Saharan Africa: a modelling study.

Science.gov (United States)

Sauboin, Christophe J; Van Bellinghen, Laure-Anne; Van De Velde, Nicolas; Van Vlaenderen, Ilse

2015-12-23

Adding malaria vaccination to existing interventions could help to reduce the health burden due to malaria. This study modelled the potential public health impact of the RTS,S candidate malaria vaccine in 42 malaria-endemic countries in sub-Saharan Africa. An individual-based Markov cohort model was constructed with three categories of malaria transmission intensity and six successive malaria immunity levels. The cycle time was 5 days. Vaccination was assumed to reduce the risk of infection, with no other effects. Vaccine efficacy was assumed to wane exponentially over time. Malaria incidence and vaccine efficacy data were taken from a Phase III trial of the RTS,S vaccine with 18 months of follow-up (NCT00866619). The model was calibrated to reproduce the malaria incidence in the control arm of the trial in each transmission category and published age distribution data. Individual-level heterogeneity in malaria exposure and vaccine protection was accounted for. Parameter uncertainty and variability were captured by using stochastic model transitions. The model followed a cohort from birth to 10 years of age without malaria vaccination, or with RTS,S malaria vaccination administered at age 6, 10 and 14 weeks or at age 6, 7-and-a-half and 9 months. Median and 95% confidence intervals were calculated for the number of clinical malaria cases, severe cases, malaria hospitalizations and malaria deaths expected to be averted by each vaccination strategy. Univariate sensitivity analysis was conducted by varying the values of key input parameters. Vaccination assuming the coverage of diphtheria-tetanus-pertussis (DTP3) at age 6, 10 and 14 weeks is estimated to avert over five million clinical malaria cases, 119,000 severe malaria cases, 98,600 malaria hospitalizations and 31,000 malaria deaths in the 42 countries over the 10-year period. Vaccination at age 6, 7-and-a-half and 9 months with 75% of DTP3 coverage is estimated to avert almost 12.5 million clinical malaria cases

Domestic Larval Control Practices and Malaria Prevalence among Under-Five Children in Burkina Faso.

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Souleymane Diabaté

Full Text Available Larval source management has contributed to malaria decline over the past years. However, little is known about the impact of larval control practices undertaken at the household level on malaria transmission.The study was conducted in Kaya health district after the 2010 mass distribution of insecticide treated-nets and the initiation of malaria awareness campaigns in Burkina Faso. The aim was to (i estimate the level of domestic larval control practices (cleaning of the house and its surroundings, eradication of larval sources, and elimination of hollow objects that might collect water; (ii identify key determinants; and (iii explore the structural relationships between these practices, participation in awareness-raising activities and mothers' knowledge/attitudes/practices, and malaria prevalence among under-five children.Overall, 2004 households were surveyed and 1,705 under-five children were examined. Half of the mothers undertook at least one action to control larval proliferation. Mothers who had gone to school had better knowledge about malaria and were more likely to undertake domestic larval control practices. Living in highly exposed rural areas significantly decreased the odds of undertaking larval control actions. Mothers' participation in malaria information sessions increased the adoption of vector control actions and bednet use. Malaria prevalence was statistically lower among children in households where mothers had undertaken at least one vector control action or used bed-nets. There was a 0.16 standard deviation decrease in malaria prevalence for every standard deviation increase in vector control practices. The effect of bednet use on malaria prevalence was of the same magnitude.Cleaning the house and its surroundings, eradicating breeding sites, and eliminating hollow objects that might collect water play a substantial role in preventing malaria among under-five. There is a need for national malaria control programs to

Socio-cultural factors associated with malaria transmission: a review.

Science.gov (United States)

Pinikahana, J

1992-06-01

Poverty creates preconditions for malaria and ways for its spread, thereby making it difficult to control malaria. Individual perceptions of illness, in this case malaria, determine people's response to seeking medical care. For example, in Orissa state, India, tribal peoples do not take treatment for malaria or take part in parasite control because they do not consider mosquito bites to be harmful and consider malaria as a mild disease. Untreated people are potential sources of malaria infection. Research from rural areas in other developing countries show the widespread belief that mosquitoes do not transmit malaria. The bad smell emitted by insecticides keep people from various areas in developing countries from spraying their households. The practice forbidding nonkin males from entering houses where only women assemble (purdah) prevents teams from spraying Muslim households in Sri Lanka. Thus, refusal to allow spraying increases the density of mosquitoes, resulting in an increased frequency of mosquito bites, and spread of malaria. Sleeping habits which contribute to the spread of malaria include not using mosquito nets or any protective device, outdoor sleeping, and children sharing a bed. People should protect themselves from mosquito bites by using bed nets, protective repellents, and screening and site selection for dwellings. A study in the Gambia revealed that, among 3 ethnic groups, Mandinkas children had the lowest prevalence rate because almost everyone used bed nets while 1-6% of people in Fula and Wolof villages did. Further, Mandinka children slept on mattresses and the other children slept on the floor. Research needs to examine whether cultural beliefs and values or poverty prevent some people from not using bed nets or any other protective device.

Safety and immunogenicity of an AMA-1 malaria vaccine in Malian adults: results of a phase 1 randomized controlled trial.

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Mahamadou A Thera

2008-01-01

Full Text Available The objective was to evaluate the safety, reactogenicity and immunogenicity of the AMA-1-based blood-stage malaria vaccine FMP2.1/AS02A in adults exposed to seasonal malaria.A phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02A is a recombinant protein (FMP2.1 based on apical membrane antigen-1 (AMA-1 from the 3D7 clone of P. falciparum, adjuvanted with AS02A. The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert. Sixty healthy, malaria-experienced adults aged 18-55 y were recruited into 2 cohorts and randomized to receive either a half dose or full dose of the malaria vaccine (FMP2.1 25 microg/AS02A 0.25 mL or FMP2.1 50 microg/AS02A 0.5 mL or rabies vaccine given in 3 doses at 0, 1 and 2 mo, and were followed for 1 y. Solicited symptoms were assessed for 7 d and unsolicited symptoms for 30 d after each vaccination. Serious adverse events were assessed throughout the study. Titers of anti-AMA-1 antibodies were measured by ELISA and P. falciparum growth inhibition assays were performed on sera collected at pre- and post-vaccination time points. Transient local pain and swelling were common and more frequent in both malaria vaccine dosage groups than in the comparator group. Anti-AMA-1 antibodies increased significantly in both malaria vaccine groups, peaking at nearly 5-fold and more than 6-fold higher than baseline in the half-dose and full-dose groups, respectively.The FMP2.1/AS02A vaccine had a good safety profile, was well-tolerated, and was highly immunogenic in malaria-exposed adults. This malaria vaccine is being evaluated in Phase 1 and 2 trials in children at this site.

PENYEBARAN KASUS DAN HABITAT PERKEMBANGBIAKAN VEKTOR MALARIA DI KABUPATEN SUMBA TIMUR PROVINSI NUSA TENGGARA TIMUR

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Ruben Wadu Willa

2016-03-01

Full Text Available East Sumba is a district in Sumba Island with high endemicity of malaria. The environment condition and geographical location can support the spread of malaria infection. This is a cross-sectional design research. The result shows that the spreading of malaria case is in 0 to 1000 meters from human settlements and spread evenly in remote villages. Breeding habitat are buffalo footprints, puddles, rice fields, rivers, buffalo wallows, gutters and trenches. With pH of water around 7 until 9 and the highest salt concentration is 1 ppm. It’s breeding habitat is more in the turbid water and exposed by sunlight directy. Types of water biota which is exist on the breeding habitat are alga, moss, grass, paddy, Aplocheilus panchax, Oreochromis sp. and water hyacinth. As the conclusion, malaria case spreads indigenously and the area is very potential for  Anopheles spp. to breed.

Congenital malaria in China.

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Zhi-Yong Tao

2014-03-01

Full Text Available BACKGROUND: Congenital malaria, in which infants are directly infected with malaria parasites from their mother prior to or during birth, is a potentially life-threatening condition that occurs at relatively low rates in malaria-endemic regions. It is recognized as a serious problem in Plasmodium falciparum-endemic sub-Saharan Africa, where recent data suggests that it is more common than previously believed. In such regions where malaria transmission is high, neonates may be protected from disease caused by congenital malaria through the transfer of maternal antibodies against the parasite. However, in low P. vivax-endemic regions, immunity to vivax malaria is low; thus, there is the likelihood that congenital vivax malaria poses a more significant threat to newborn health. Malaria had previously been a major parasitic disease in China, and congenital malaria case reports in Chinese offer valuable information for understanding the risks posed by congenital malaria to neonatal health. As most of the literature documenting congenital malaria cases in China are written in Chinese and therefore are not easily accessible to the global malaria research community, we have undertaken an extensive review of the Chinese literature on this subject. METHODS/PRINCIPAL FINDINGS: Here, we reviewed congenital malaria cases from three major searchable Chinese journal databases, concentrating on data from 1915 through 2011. Following extensive screening, a total of 104 cases of congenital malaria were identified. These cases were distributed mainly in the eastern, central, and southern regions of China, as well as in the low-lying region of southwest China. The dominant species was P. vivax (92.50%, reflecting the malaria parasite species distribution in China. The leading clinical presentation was fever, and other clinical presentations were anaemia, jaundice, paleness, diarrhoea, vomiting, and general weakness. With the exception of two cases, all patients

Socio-demographic factors influencing knowledge, attitude and practice (KAP) regarding malaria in Bangladesh.

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Bashar, Kabirul; Al-Amin, H M; Reza, Md Selim; Islam, Muzahidul; Asaduzzaman; Ahmed, Touhid Uddin

2012-12-18

A clear understanding of the social and behavioral risk factors, and knowledge gaps, related to exposure to malaria are essential when developing guidelines and recommendations for more effective disease prevention in many malaria endemic areas of the world including Bangladesh and elsewhere in the South East Asia. To-date, the level of knowledge that human populations, residing in moderate to high malaria risk zones, have with respect to the basic pathogen transmission dynamics, risk factors for malaria or disease preventative strategies, has not been assessed in Bangladesh. The purpose of this study was to address this gap by conducting surveys of the knowledge, attitudes and practices (KAP) of people, from variable socio-demographic backgrounds, residing in selected rural malaria endemic areas in Bangladesh. The KAP survey was conducted in portions of six different malaria endemic districts in Bangladesh from July to October 2011. The survey consisted of interviewing residence of these malaria endemic districts using a structured questionnaire and interviewers also completed observational checklists at each household where people were interviewed. The study area was further divided into two zones (1 and 2) based on differences in the physical geography and level of malaria endemicity in the two zones. Data from the questionnaires and observational checklists were analysised using Statistical Package for Social Sciences 16.0 (SPSS, Inc., Chicago, IL, USA). A total of 468 individuals from individual households were interviewed, and most respondents were female. Monthly incomes varied within and among the zones. It was found that 46.4% and 41% of respondents' family had malaria within the past one year in zones 1 and 2, respectively. Nearly 86% of the respondents did not know the exact cause of malaria or the role of Anopheles mosquitoes in the pathogen's transmission. Knowledge on malaria transmission and symptoms of the respondents of zones 1 and 2 were

Human skin emanations in the host-seeking behaviour of the malaria mosquito Anopheles gambiae

NARCIS (Netherlands)

Braks, M.

1999-01-01

Malaria is an infectious disease caused by a parasite ( Plasmodium spp.) that is transmitted between human individuals by mosquitoes, belonging to the order of insects, Diptera, family of Culicidae (mosquitoes) and genus of Anopheles (malaria

The demographics of human and malaria movement and migration patterns in East Africa.

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Pindolia, Deepa K; Garcia, Andres J; Huang, Zhuojie; Smith, David L; Alegana, Victor A; Noor, Abdisalan M; Snow, Robert W; Tatem, Andrew J

2013-11-05

The quantification of parasite movements can provide valuable information for control strategy planning across all transmission intensities. Mobile parasite carrying individuals can instigate transmission in receptive areas, spread drug resistant strains and reduce the effectiveness of control strategies. The identification of mobile demographic groups, their routes of travel and how these movements connect differing transmission zones, potentially enables limited resources for interventions to be efficiently targeted over space, time and populations. National population censuses and household surveys provide individual-level migration, travel, and other data relevant for understanding malaria movement patterns. Together with existing spatially referenced malaria data and mathematical models, network analysis techniques were used to quantify the demographics of human and malaria movement patterns in Kenya, Uganda and Tanzania. Movement networks were developed based on connectivity and magnitudes of flow within each country and compared to assess relative differences between regions and demographic groups. Additional malaria-relevant characteristics, such as short-term travel and bed net use, were also examined. Patterns of human and malaria movements varied between demographic groups, within country regions and between countries. Migration rates were highest in 20-30 year olds in all three countries, but when accounting for malaria prevalence, movements in the 10-20 year age group became more important. Different age and sex groups also exhibited substantial variations in terms of the most likely sources, sinks and routes of migration and malaria movement, as well as risk factors for infection, such as short-term travel and bed net use. Census and survey data, together with spatially referenced malaria data, GIS and network analysis tools, can be valuable for identifying, mapping and quantifying regional connectivities and the mobility of different demographic

The Development of Plasmodium falciparum-Specific IL10 CD4 T Cells and Protection from Malaria in Children in an Area of High Malaria Transmission.

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Boyle, Michelle J; Jagannathan, Prasanna; Bowen, Katherine; McIntyre, Tara I; Vance, Hilary M; Farrington, Lila A; Schwartz, Alanna; Nankya, Felistas; Naluwu, Kate; Wamala, Samuel; Sikyomu, Esther; Rek, John; Greenhouse, Bryan; Arinaitwe, Emmanuel; Dorsey, Grant; Kamya, Moses R; Feeney, Margaret E

2017-01-01

Cytokine-producing CD4 T cells have important roles in immunity against Plasmodium falciparum (Pf) malaria. However, the factors influencing functional differentiation of Pf- specific CD4 T cells in naturally exposed children are not well understood. Moreover, it is not known which CD4 T-cell cytokine-producing subsets are most critical for protection. We measured Pf- specific IFNγ-, IL10-, and TNFα-producing CD4 T-cell responses by multi-parametric flow cytometry in 265 children aged 6 months to 10 years enrolled in a longitudinal observational cohort in a high malaria transmission site in Uganda. We found that both age and parasite burden were independently associated with cytokine production by CD4 T cells. IL10 production by IFNγ + CD4 T cells was higher in younger children and in those with high-parasite burden during recent infection. To investigate the role of CD4 T cells in immunity to malaria, we measured associations of Pf -specific CD4 cytokine-producing cells with the prospective risk of Pf infection and clinical malaria, adjusting for household exposure to Pf -infected mosquitos. Overall, the prospective risk of infection was not associated with the total frequency of Pf- specific CD4 T cells, nor of any cytokine-producing CD4 subset. However, the frequency of CD4 cells producing IL10 but not inflammatory cytokines (IFNγ and TNFα) was associated with a decreased risk of clinical malaria once infected. These data suggest that functional polarization of the CD4 T-cell response may modulate the clinical manifestations of malaria and play a role in naturally acquired immunity.

Assessment of climate-driven variations in malaria incidence in Swaziland: toward malaria elimination.

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Chuang, Ting-Wu; Soble, Adam; Ntshalintshali, Nyasatu; Mkhonta, Nomcebo; Seyama, Eric; Mthethwa, Steven; Pindolia, Deepa; Kunene, Simon

2017-06-01

Swaziland aims to eliminate malaria by 2020. However, imported cases from neighbouring endemic countries continue to sustain local parasite reservoirs and initiate transmission. As certain weather and climatic conditions may trigger or intensify malaria outbreaks, identification of areas prone to these conditions may aid decision-makers in deploying targeted malaria interventions more effectively. Malaria case-surveillance data for Swaziland were provided by Swaziland's National Malaria Control Programme. Climate data were derived from local weather stations and remote sensing images. Climate parameters and malaria cases between 2001 and 2015 were then analysed using seasonal autoregressive integrated moving average models and distributed lag non-linear models (DLNM). The incidence of malaria in Swaziland increased between 2005 and 2010, especially in the Lubombo and Hhohho regions. A time-series analysis indicated that warmer temperatures and higher precipitation in the Lubombo and Hhohho administrative regions are conducive to malaria transmission. DLNM showed that the risk of malaria increased in Lubombo when the maximum temperature was above 30 °C or monthly precipitation was above 5 in. In Hhohho, the minimum temperature remaining above 15 °C or precipitation being greater than 10 in. might be associated with malaria transmission. This study provides a preliminary assessment of the impact of short-term climate variations on malaria transmission in Swaziland. The geographic separation of imported and locally acquired malaria, as well as population behaviour, highlight the varying modes of transmission, part of which may be relevant to climate conditions. Thus, the impact of changing climate conditions should be noted as Swaziland moves toward malaria elimination.

Visualizing the uncertainty in the relationship between seasonal average climate and malaria risk.

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MacLeod, D A; Morse, A P

2014-12-02

Around $1.6 billion per year is spent financing anti-malaria initiatives, and though malaria morbidity is falling, the impact of annual epidemics remains significant. Whilst malaria risk may increase with climate change, projections are highly uncertain and to sidestep this intractable uncertainty, adaptation efforts should improve societal ability to anticipate and mitigate individual events. Anticipation of climate-related events is made possible by seasonal climate forecasting, from which warnings of anomalous seasonal average temperature and rainfall, months in advance are possible. Seasonal climate hindcasts have been used to drive climate-based models for malaria, showing significant skill for observed malaria incidence. However, the relationship between seasonal average climate and malaria risk remains unquantified. Here we explore this relationship, using a dynamic weather-driven malaria model. We also quantify key uncertainty in the malaria model, by introducing variability in one of the first order uncertainties in model formulation. Results are visualized as location-specific impact surfaces: easily integrated with ensemble seasonal climate forecasts, and intuitively communicating quantified uncertainty. Methods are demonstrated for two epidemic regions, and are not limited to malaria modeling; the visualization method could be applied to any climate impact.

Reducing microscopy-based malaria misdiagnosis in a low-resource area of Tanzania.

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Allen, Lisa K; Hatfield, Jennifer M; Manyama, Mange

2013-01-01

Misdiagnosis of malaria is a major problem in Africa leading not only to incorrect individual level treatment, but potentially the acceleration of the spread of drug resistance in low-transmission areas. In this paper we report on the outcomes of a simple intervention that utilized a social entrepreneurship approach (SEA) to reduce misdiagnosis associated with hospital-based microscopy of malaria in a low-transmission area of rural Tanzania. A pre-post assessment was conducted on patients presenting to the hospital outpatient department with malaria and non-malaria like symptoms in January 2009 (pre-intervention) and June 2009 (post-intervention). All participants were asked a health seeking behavior questionnaire and blood samples were taken for local and quality control microscopy. Multivariate logistic regression was conducted to determine magnitude of misdiagnosis with local microscopy pre- versus- post intervention. Local microscopy pre-intervention specificity was 29.5% (95% CI = 21.6% - 38.4%) whereas the post intervention specificity was 68.6% (95% CI = 60.2% - 76.2%). Both pre and post intervention sensitivity were difficult to determine due to an unexpected low number of true positive cases. The proportion of participants misdiagnosed pre-intervention was 70.2% (95%CI = 61.3%-78.0%) as compared to 30.6% (95%CI = 23.2%-38.8%) post-intervention. This resulted in a 39.6% reduction in misdiagnosis of malaria at the local hospital. The magnitude of misdiagnosis for the pre-intervention participants was 5.3 (95%CI = 3.1-9.3) that of the post-intervention participants. In conclusion, this study provides evidence that a simple intervention can meaningfully reduce the magnitude of microscopy-based misdiagnosis of malaria for those individuals seeking treatment for uncomplicated malaria. We anticipate that this intervention will facilitate a valuable and sustainable change in malaria diagnosis at the local hospital.

Malaria in Children.

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Cohee, Lauren M; Laufer, Miriam K

2017-08-01

Malaria is a leading cause of morbidity and mortality in endemic areas, leading to an estimated 438,000 deaths in 2015. Malaria is also an important health threat to travelers to endemic countries and should be considered in evaluation of any traveler returning from a malaria-endemic area who develops fever. Considering the diagnosis of malaria in patients with potential exposure is critical. Prompt provision of effective treatment limits the complications of malaria and can be life-saving. Understanding Plasmodium species variation, epidemiology, and drug-resistance patterns in the geographic area where infection was acquired is important for determining treatment choices. Copyright © 2017 Elsevier Inc. All rights reserved.

DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMASIII AND DMASIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC

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DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMAsIII and DMAsIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC. L. M. Del Razo1, M. Styblo2, W. R. Cullen3, and D.J. Thomas4. 1Toxicology Section, Cinvestav-IPN, Mexico, D.F., 2Univ. North Carolina, Chapel Hill, NC; 3Uni...

C5a enhances dysregulated inflammatory and angiogenic responses to malaria in vitro: potential implications for placental malaria.

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Andrea Conroy

Full Text Available Placental malaria (PM is a leading cause of maternal and infant mortality. Although the accumulation of parasitized erythrocytes (PEs and monocytes within the placenta is thought to contribute to the pathophysiology of PM, the molecular mechanisms underlying PM remain unclear. Based on the hypothesis that excessive complement activation may contribute to PM, in particular generation of the potent inflammatory peptide C5a, we investigated the role of C5a in the pathogenesis of PM in vitro and in vivo.Using primary human monocytes, the interaction between C5a and malaria in vitro was assessed. CSA- and CD36-binding PEs induced activation of C5 in the presence of human serum. Plasmodium falciparum GPI (pfGPI enhanced C5a receptor expression (CD88 on monocytes, and the co-incubation of monocytes with C5a and pfGPI resulted in the synergistic induction of cytokines (IL-6, TNF, IL-1beta, and IL-10, chemokines (IL-8, MCP-1, MIP1alpha, MIP1beta and the anti-angiogenic factor sFlt-1 in a time and dose-dependent manner. This dysregulated response was abrogated by C5a receptor blockade. To assess the potential role of C5a in PM, C5a plasma levels were measured in malaria-exposed primigravid women in western Kenya. Compared to pregnant women without malaria, C5a levels were significantly elevated in women with PM.These results suggest that C5a may contribute to the pathogenesis of PM by inducing dysregulated inflammatory and angiogenic responses that impair placental function.

Defining childhood severe falciparum malaria for intervention studies.

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Philip Bejon

2007-08-01

Full Text Available Clinical trials of interventions designed to prevent severe falciparum malaria in children require a clear endpoint. The internationally accepted definition of severe malaria is sensitive, and appropriate for clinical purposes. However, this definition includes individuals with severe nonmalarial disease and coincident parasitaemia, so may lack specificity in vaccine trials. Although there is no "gold standard" individual test for severe malaria, malaria-attributable fractions (MAFs can be estimated among groups of children using a logistic model, which we use to test the suitability of various case definitions as trial endpoints.A total of 4,583 blood samples were taken from well children in cross-sectional surveys and from 1,361 children admitted to a Kenyan District hospital with severe disease. Among children under 2 y old with severe disease and over 2,500 parasites per microliter of blood, the MAFs were above 85% in moderate- and low-transmission areas, but only 61% in a high-transmission area. HIV and malnutrition were not associated with reduced MAFs, but gastroenteritis with severe dehydration (defined by reduced skin turgor, lower respiratory tract infection (clinician's final diagnosis, meningitis (on cerebrospinal fluid [CSF] examination, and bacteraemia were associated with reduced MAFs. The overall MAF was 85% (95% confidence interval [CI] 83.8%-86.1% without excluding these conditions, 89% (95% CI 88.4%-90.2% after exclusions, and 95% (95% CI 94.0%-95.5% when a threshold of 2,500 parasites/mul was also applied. Applying a threshold and exclusion criteria reduced sensitivity to 80% (95% CI 77%-83%.The specificity of a case definition for severe malaria is improved by applying a parasite density threshold and by excluding children with meningitis, lower respiratory tract infection (clinician's diagnosis, bacteraemia, and gastroenteritis with severe dehydration, but not by excluding children with HIV or malnutrition.

Knowledge of malaria and practice of home management of malaria ...

African Journals Online (AJOL)

Background: Malaria is a preventable and treatable disease associated with high morbidity and mortality. It is the 3rd leading cause of death for children under five years worldwide. Home-based management of malaria may go a long way in reducing the attending morbidity and mortality associated with malaria in this group ...

Spatial prediction of malaria prevalence in an endemic area of Bangladesh

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Islam Akramul

2010-05-01

Full Text Available Abstract Background Malaria is a major public health burden in Southeastern Bangladesh, particularly in the Chittagong Hill Tracts region. Malaria is endemic in 13 districts of Bangladesh and the highest prevalence occurs in Khagrachari (15.47%. Methods A risk map was developed and geographic risk factors identified using a Bayesian approach. The Bayesian geostatistical model was developed from previously identified individual and environmental covariates (p Results Predicted high prevalence areas were located along the north-eastern areas, and central part of the study area. Low to moderate prevalence areas were predicted in the southwestern, southeastern and central regions. Individual age and nearness to fragmented forest were associated with malaria prevalence after adjusting the spatial auto-correlation. Conclusion A Bayesian analytical approach using multiple enabling technologies (geographic information systems, global positioning systems, and remote sensing provide a strategy to characterize spatial heterogeneity in malaria risk at a fine scale. Even in the most hyper endemic region of Bangladesh there is substantial spatial heterogeneity in risk. Areas that are predicted to be at high risk, based on the environment but that have not been reached by surveys are identified.

Altered activity of heme biosynthesis pathway enzymes in individuals chronically exposed to arsenic in Mexico

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Hernandez-Zavala, A.; Del Razo, L.M.; Garcia-Vargas, G.G.; Aguilar, C.; Borja, V.H.; Albores, A.; Cebrian, M.E. [CINVESTAV-IPN, Mexico (Mexico). Dept. de Farmacologia y Toxicologica

1999-03-01

Our objective was to evaluate the activities of some enzymes of the heme biosynthesis pathway and their relationship with the profile of urinary porphyrin excretion in individuals exposed chronically to arsenic (As) via drinking water in Region Lagunera, Mexico. We selected 17 individuals from each village studied: Benito Juarez, which has current exposure to 0.3 mg As/l; Santa Ana, where individuals have been exposed for more than 35 years to 0.4 mg As/l, but due to changes in the water supply (in 1992) exposure was reduced to its current level (0.1 mg As/l), and Nazareno, with 0.014 mg As/l. Average arsenic concentrations in urine were 2058, 398, and 88 {mu}g As/g creatinine, respectively. The more evident alterations in heme metabolism observed in the highly exposed individuals were: (1) small but significant increases in porphobilinogen deaminase (PBG-D) and uroporphyrinogen decarboxylase (URO-D) activities in peripheral blood erythrocytes; (2) increases in the urinary excretion of total porphyrins, mainly due to coproporphyrin III (COPROIII) and uroporphyrin III (UROIII); and (3) increases in the COPRO/URO and COPROIII/COPROI ratios. No significant changes were observed in uroporphyrinogen III synthetase (UROIII-S) activity. The direct relationships between enzyme activities and urinary porphyrins, suggest that the increased porphyrin excretion was related to PBG-D, whereas the increased URO-D activity would enhance coproporphyrin synthesis and excretion at the expense of uroporphyrin. None of the human studies available have reported the marked porphyric response and enzyme inhibition observed in rodents. In conclusion, chronic As exposure alters human heme metabolism; however the severity of the effects appears to depend on characteristics of exposure not yet fully characterized. (orig.) With 1 fig., 3 tabs., 20 refs.

Accelerating to Zero: Strategies to Eliminate Malaria in the Peruvian Amazon

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Quispe, Antonio M.; Llanos-Cuentas, Alejandro; Rodriguez, Hugo; Clendenes, Martin; Cabezas, Cesar; Leon, Luis M.; Chuquiyauri, Raul; Moreno, Marta; Kaslow, David C.; Grogl, Max; Herrera, Sócrates; Magill, Alan J.; Kosek, Margaret; Vinetz, Joseph M.; Lescano, Andres G.; Gotuzzo, Eduardo

2016-01-01

In February 2014, the Malaria Elimination Working Group, in partnership with the Peruvian Ministry of Health (MoH), hosted its first international conference on malaria elimination in Iquitos, Peru. The 2-day meeting gathered 85 malaria experts, including 18 international panelists, 23 stakeholders from different malaria-endemic regions of Peru, and 11 MoH authorities. The main outcome was consensus that implementing a malaria elimination project in the Amazon region is achievable, but would require: 1) a comprehensive strategic plan, 2) the altering of current programmatic guidelines from control toward elimination by including symptomatic as well as asymptomatic individuals for antimalarial therapy and transmission-blocking interventions, and 3) the prioritization of community-based active case detection with proper rapid diagnostic tests to interrupt transmission. Elimination efforts must involve key stakeholders and experts at every level of government and include integrated research activities to evaluate, implement, and tailor sustainable interventions appropriate to the region.

UK malaria treatment guidelines 2016.

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Lalloo, David G; Shingadia, Delane; Bell, David J; Beeching, Nicholas J; Whitty, Christopher J M; Chiodini, Peter L

2016-06-01

. Primaquine should be avoided or given with caution under expert supervision in patients with Glucose-6-phosphate dehydrogenase deficiency (G6PD), in whom it may cause severe haemolysis. 22. Primaquine (for eradication of P. vivax or P. ovale hypnozoites) is contraindicated in pregnancy and when breastfeeding (until the G6PD status of child is known); after initial treatment for these infections a pregnant woman should take weekly chloroquine prophylaxis until after delivery or cessation of breastfeeding when hypnozoite eradication can be considered. 23. An acute attack of malaria does not confer protection from future attacks: individuals who have had malaria should take effective anti-mosquito precautions and chemoprophylaxis during future visits to endemic areas. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

[Congenital malaria due to Plasmodium falciparum and Plasmodium malariae].

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Zenz, W; Trop, M; Kollaritsch, H; Reinthaler, F

2000-05-19

Increasing tourism and growing numbers of immigrants from malaria-endemic countries are leading to a higher importation rate of rare tropical disorders in European countries. We describe, to the best of our knowledge, the first case of connatal malaria in Austria. The patient is the first child of a 24 year old mother who was born in Ghana and immigrated to Austria one and a half years before delivery. She did not stay in an endemic region during this period and did not show fever or any other signs of malaria. The boy was healthy for the first six weeks of his life. In the 8th week of life he was admitted to our hospital due to persistent fever of unknown origin. On physical examination he showed only mild splenomegaly. Routine laboratory testing revealed mild hemolytic anemia with a hemoglobin value of 8.3 g/l. In the blood smear Plasmodium falciparum and Plasmodium malariae were detected. Oral therapy with quinine hydrochloride was successful and blood smears became negative for Plasmodia within 6 days. This case shows that congenital malaria can occur in children of clinically healthy women who were born in malaria-endemic areas even one and a half year after they have immigrated to non-endemic regions.

Rapid urban malaria appraisal (RUMA I: Epidemiology of urban malaria in Ouagadougou

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Convelbo Natalie

2005-09-01

Full Text Available Abstract Background Rapid urbanization in sub-Saharan Africa has a major impact on malaria epidemiology. While much is known about malaria in rural areas in Burkina Faso, the urban situation is less well understood. Methods An assessment of urban malaria was carried out in Ouagadougou in November -December, 2002 during which a rapid urban malaria appraisal (RUMA was applied. Results The school parasitaemia prevalence was relatively high (48.3% at the cold and dry season 2002. Routine malaria statistics indicated that seasonality of malaria transmission was marked. In the health facilities, the number of clinical cases diminished quickly at the start of the cold and dry season and the prevalence of parasitaemia detected in febrile and non-febrile cases was 21.1% and 22.0%, respectively. The health facilities were likely to overestimate the malaria incidence and the age-specific fractions of malaria-attributable fevers were low (0–0.13. Peak prevalence tended to occur in older children (aged 6–15 years. Mapping of Anopheles sp. breeding sites indicated a gradient of endemicity between the urban centre and the periphery of Ouagadougou. A remarkable link was found between urban agriculture activities, seasonal availability of water supply and the occurrence of malaria infections in this semi-arid area. The study also demonstrated that the usage of insecticide-treated nets and the education level of family caretakers played a key role in reducing malaria infection rates. Conclusion These findings show that determining local endemicity and the rate of clinical malaria cases are urgently required in order to target control activities and avoid over-treatment with antimalarials. The case management needs to be tailored to the level of the prevailing endemicity.

Fighting malaria in Madhya Pradesh (Central India: Are we loosing the battle?

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Thimasarn Krongthong

2009-05-01

Full Text Available Abstract Malaria control in Madhya Pradesh is complex because of vast tracts of forest with tribal settlement. Fifty four million individuals of various ethnic origins, accounting for 8% of the total population of India, contributed 30% of total malaria cases, 60% of total falciparum cases and 50% of malaria deaths in the country. Ambitious goals to control tribal malaria by launching "Enhanced Malaria Control Project" (EMCP by the National Vector Borne Disease Control Programme (NVBDCP, with the World Bank assistance, became effective in September 1997 in eight north Indian states. Under EMCP, the programme used a broader mix of new interventions, i.e. insecticide-treated bed nets, spraying houses with effective residual insecticides, use of larvivorous fishes, rapid diagnostic tests for prompt diagnosis, treatment of the sick with effective radical treatment and increased public awareness and IEC. However, the challenge is to scale up these services. A retrospective analysis of data on malaria morbidity and associated mortality reported under the existing surveillance system of the Madhya Pradesh (Central India for the years 1996–2007 was carried out to determine the impact of EMCP on malaria morbidity and associated mortality. Analysis revealed that despite the availability of effective intervention tools for the prevention and control of malaria, falciparum malaria remains uncontrolled and deaths due to malaria have increased. Precisely, the aim of this epidemiological analysis is to draw lessons applicable to all international aid efforts, bureaucracy, policy makers and programme managers in assessing its project performance as a new Global Malaria Action Plan is launched with ambitious goal of reducing malaria and its elimination by scaling up the use of existing tools.

Specific proliferative response of human lymphocytes to purified soluble antigens from Plasmodium falciparum in vitro cultures and to antigens from malaria patients' sera

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Bygbjerg, I C; Jepsen, S; Theander, T G

1985-01-01

Antigens of Plasmodium falciparum, in supernatants of in vitro cultures of the parasite were affinity purified on columns prepared with the IgG fraction of the serum of an immune individual. The purified antigens induced proliferation of lymphocytes from persons who had recently had malaria....... The responses were strongest with lymphocytes from individuals infected with falciparum and ovale malaria; vivax malaria infections induced a lower level of response and lymphocytes of unsensitized individuals were little affected. Lymphocytes from unsensitized individuals did not respond to the affinity...

The economic burden of malaria.

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Gallup, J L; Sachs, J D

2001-01-01

Malaria and poverty are intimately connected. Controlling for factors such as tropical location, colonial history, and geographical isolation, countries with intensive malaria had income levels in 1995 of only 33% that of countries without malaria, whether or not the countries were in Africa. The high levels of malaria in poor countries are not mainly a consequence of poverty. Malaria is geographically specific. The ecological conditions that support the more efficient malaria mosquito vectors primarily determine the distribution and intensity of the disease. Intensive efforts to eliminate malaria in the most severely affected tropical countries have been largely ineffective. Countries that have eliminated malaria in the past half century have all been either subtropical or islands. These countries' economic growth in the 5 years after eliminating malaria has usually been substantially higher than growth in the neighboring countries. Cross-country regressions for the 1965-1990 period confirm the relationship between malaria and economic growth. Taking into account initial poverty, economic policy, tropical location, and life expectancy, among other factors, countries with intensive malaria grew 1.3% less per person per year, and a 10% reduction in malaria was associated with 0.3% higher growth. Controlling for many other tropical diseases does not change the correlation of malaria with economic growth, and these diseases are not themselves significantly negatively correlated with economic growth. A second independent measure of malaria has a slightly higher correlation with economic growth in the 1980-1996 period. We speculate about the mechanisms that could cause malaria to have such a large impact on the economy, such as foreign investment and economic networks within the country.

Dosimetric methodology for extremities of individuals occupationally exposed to beta radiation using the optically stimulated luminescence technique

International Nuclear Information System (INIS)

Pinto, Teresa Cristina Nathan Outeiro

2010-01-01

A dosimetric methodology was established for the determination of extremity doses of individuals occupationally exposed to beta radiation, using Al 2 O 3 :C detectors and the optically stimulated luminescence (OSL) reader system microStar, Landauer. The main parts of the work were: characterization of the dosimetric material Al 2 O 3 :C using the OSL technique; establishment of the dose evaluation methodology; dose rate determination of beta radiation sources; application of the established method in a practical test with individuals occupationally exposed to beta radiation during a calibration simulation of clinical applicators; validation of the methodology by the comparison between the dose results of the practical test using the OSL and the thermoluminescence (TL) techniques. The results show that both the OSL Al-2O 3 :C detectors and the technique may be utilized for individual monitoring of extremities and beta radiation. (author)

The epidemiology of febrile malaria episodes in an area of unstable and seasonal transmission

DEFF Research Database (Denmark)

Giha, H A; Rosthoj, S; Dodoo, D

2000-01-01

hazard model for recurrent events stratified by family, we have calculated the relative hazard for clinical malaria episodes by age, sex, haemoglobin genotype, blood type and infection in the previous season. The malaria risk was significantly lower in individuals aged 20-88 years than in the 5-19 years...

Performance of “VIKIA Malaria Ag Pf/Pan” (IMACCESS®, a new malaria rapid diagnostic test for detection of symptomatic malaria infections

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Chou Monidarin

2012-08-01

Full Text Available Abstract Background Recently, IMACCESS® developed a new malaria test (VIKIA Malaria Ag Pf/Pan™, based on the detection of falciparum malaria (HRP-2 and non-falciparum malaria (aldolase. Methods The performance of this new malaria rapid diagnostic test (RDT was assessed using 1,000 febrile patients seeking malaria treatment in four health centres in Cambodia from August to December 2011. The results of the VIKIA Malaria Ag Pf/Pan were compared with those obtained by microscopy, the CareStart Malaria™ RDT (AccessBio® which is currently used in Cambodia, and real-time PCR (as “gold standard”. Results The best performances of the VIKIA Malaria Ag Pf/Pan™ test for detection of both Plasmodium falciparum and non-P. falciparum were with 20–30 min reading times (sensitivity of 93.4% for P. falciparum and 82.8% for non-P. falciparum and specificity of 98.6% for P. falciparum and 98.9% for non-P. falciparum and were similar to those for the CareStart Malaria™ test. Conclusions This new RDT performs similarly well as other commercially available tests (especially the CareStart Malaria™ test, used as comparator, and conforms to the World Health Organization’s recommendations for RDT performance. It is a good alternative tool for the diagnosis of malaria in endemic areas.

Modern immunological approaches to assess malaria transmission and immunity and to diagnose plasmodial infection

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C. T. Daniel-Ribeiro

1992-01-01

Full Text Available The present paper reviews our recent data concerning the use of immunological methods employing monoclonal antibodies and synthetic peptides to study malaria transmission and immunity and to diagnose plasmodial infection. As concerns malaria transmission, we studied the main vectors of human malaria and the plasmodial species transmitted in endemic areas of Rondônia state, Brazil. The natural infection on anopheline was evaluated by immunoradiometric assay (IRMA using monoclonal antibodies to an immunodominant sporozoite surface antigen (CS protein demonstrated to be species specific. Our results showed that among six species of Anopheles found infected, An. darlingi was the main vector transmitting Plasmodium falciparum and P. vivax malaria in the immediate vicinity of houses. In order to assess the level of anti-CS antibodies we studied, by IRMA using the synthetic peptide corresponding to the repetitive epitope of the sporozoite CS protein, sera of individuals living in the same areas where the entomological survey has been performed. In this assay the prevalence of anti-CS antibodies was very low and did not reflect the malaria transmission rate in the studied areas. In relation to malaria diagnosis, a monoclonal antibody specific to an epitope of a 50 kDa exoantigen, the major component of supernatant collected at the time of schizont rupture, was used as a probe for the detection of P. falciparum antigens. This assay seemed to be more sensitive than parasitological examination for malaria diagnosis since it was able to detect plasmodial antigens in both symptomatic and asymtomatic individuals with negative thick blood smear at different intervals after a last parasitologically confirmed confirmed attack of malaria.

Development of vaccines against Plasmodium falciparum malaria: taking lessons from naturally acquired protective immunity

DEFF Research Database (Denmark)

Hviid, Lars

2007-01-01

The acquisition of substantial anti-malarial protection in people naturally exposed to P. falciparum is often cited as evidence that malaria vaccines can be developed, but is rarely used to guide the development. We are pursuing the development of vaccines based on antigens and immune responses...

What would PCR assessment change in the management of fevers in a malaria endemic area? A school-based study in Benin in children with and without fever

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Faucher Jean-François

2010-08-01

Full Text Available Abstract Background A recent school-based study in Benin showed that applying a policy of anti-malarial prescriptions restricted to parasitologically-confirmed cases on the management of fever is safe and feasible. Additional PCR data were analysed in order to touch patho-physiological issues, such as the usefulness of PCR in the management of malaria in an endemic area or the triggering of a malaria attack in children with submicroscopic malaria. Methods PCR data were prospectively collected in the setting of an exposed (with fever/non exposed (without fever study design. All children had a negative malaria rapid diagnostic test (RDT at baseline, were followed up to day 14 and did not receive drugs with anti-malarial activity. The index group was defined by children with fever at baseline and the control group by children without fever at baseline. Children with submicroscopic malaria in these two groups were defined by a positive PCR at baseline. Results PCR was positive in 66 (27% children of the index group and in 104 (44% children of the control group respectively. The only significant factor positively related to PCR positivity at baseline was the clinical status (control group. When definition of malaria attacks included PCR results, no difference of malaria incidence was observed between the index and control groups, neither in the whole cohort, nor in children with submicroscopic malaria. The rate of undiagnosed malaria at baseline was estimated to 3.7% at baseline in the index group. Conclusions Treating all children with fever and a positive PCR would have led to a significant increase of anti-malarial consumption, with few benefits in terms of clinical events. Non malarial fevers do not or do not frequently trigger malaria attacks in children with submicroscopic malaria.

Plasmodium falciparum malaria challenge by the bite of aseptic Anopheles stephensi mosquitoes: results of a randomized infectivity trial.

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Kirsten E Lyke

2010-10-01

Full Text Available Experimental infection of malaria-naïve volunteers by the bite of Plasmodium falciparum-infected mosquitoes is a preferred means to test the protective effect of malaria vaccines and drugs. The standard model relies on the bite of five infected mosquitoes to induce malaria. We examined the efficacy of malaria transmission using mosquitoes raised aseptically in compliance with current Good Manufacturing Practices (cGMPs.Eighteen adults aged 18-40 years were randomized to receive 1, 3 or 5 bites of Anopheles stephensi mosquitoes infected with the chloroquine-sensitive NF54 strain of P. falciparum. Seventeen participants developed malaria; fourteen occurring on Day 11. The mean prepatent period was 10.9 days (9-12 days. The geometric mean parasitemia was 15.7 parasites/µL (range: 4-70 by microscopy. Polymerase chain reaction (PCR detected parasites 3.1 (range: 0-4 days prior to microscopy. The geometric mean sporozoite load was 16,753 sporozoites per infected mosquito (range: 1,000-57,500. A 1-bite participant withdrew from the study on Day 13 post-challenge and was PCR and smear negative.The use of aseptic, cGMP-compliant P. falciparum-infected mosquitoes is safe, is associated with a precise prepatent period compared to the standard model and appears more efficient than the standard approach, as it led to infection in 100% (6/6 of volunteers exposed to three mosquito bites and 83% (5/6 of volunteers exposed to one mosquito bite.ClinicalTrials.gov NCT00744133.

Malaria Research

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... with facebook share with twitter share with linkedin Malaria Go to Information for Researchers ► Credit: NIAID Colorized ... for the disease. Why Is the Study of Malaria a Priority for NIAID? Roughly 3.2 billion ...

A global model of malaria climate sensitivity: comparing malaria response to historic climate data based on simulation and officially reported malaria incidence

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Edlund Stefan

2012-09-01

Full Text Available Abstract Background The role of the Anopheles vector in malaria transmission and the effect of climate on Anopheles populations are well established. Models of the impact of climate change on the global malaria burden now have access to high-resolution climate data, but malaria surveillance data tends to be less precise, making model calibration problematic. Measurement of malaria response to fluctuations in climate variables offers a way to address these difficulties. Given the demonstrated sensitivity of malaria transmission to vector capacity, this work tests response functions to fluctuations in land surface temperature and precipitation. Methods This study of regional sensitivity of malaria incidence to year-to-year climate variations used an extended Macdonald Ross compartmental disease model (to compute malaria incidence built on top of a global Anopheles vector capacity model (based on 10 years of satellite climate data. The predicted incidence was compared with estimates from the World Health Organization and the Malaria Atlas. The models and denominator data used are freely available through the Eclipse Foundation’s Spatiotemporal Epidemiological Modeller (STEM. Results Although the absolute scale factor relating reported malaria to absolute incidence is uncertain, there is a positive correlation between predicted and reported year-to-year variation in malaria burden with an averaged root mean square (RMS error of 25% comparing normalized incidence across 86 countries. Based on this, the proposed measure of sensitivity of malaria to variations in climate variables indicates locations where malaria is most likely to increase or decrease in response to specific climate factors. Bootstrapping measures the increased uncertainty in predicting malaria sensitivity when reporting is restricted to national level and an annual basis. Results indicate a potential 20x improvement in accuracy if data were available at the level ISO 3166–2

Maternal malaria induces a procoagulant and antifibrinolytic state that is embryotoxic but responsive to anticoagulant therapy.

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John W Avery

Full Text Available Low birth weight and fetal loss are commonly attributed to malaria in endemic areas, but the cellular and molecular mechanisms that underlie these poor birth outcomes are incompletely understood. Increasing evidence suggests that dysregulated hemostasis is important in malaria pathogenesis, but its role in placental malaria (PM, characterized by intervillous sequestration of Plasmodium falciparum, proinflammatory responses, and excessive fibrin deposition is not known. To address this question, markers of coagulation and fibrinolysis were assessed in placentae from malaria-exposed primigravid women. PM was associated with significantly elevated placental monocyte and proinflammatory marker levels, enhanced perivillous fibrin deposition, and increased markers of activated coagulation and suppressed fibrinolysis in placental plasma. Submicroscopic PM was not proinflammatory but tended to be procoagulant and antifibrinolytic. Birth weight trended downward in association with placental parasitemia and high fibrin score. To directly assess the importance of coagulation in malaria-induced compromise of pregnancy, Plasmodium chabaudi AS-infected pregnant C57BL/6 mice were treated with the anticoagulant, low molecular weight heparin. Treatment rescued pregnancy at midgestation, with substantially decreased rates of active abortion and reduced placental and embryonic hemorrhage and necrosis relative to untreated animals. Together, the results suggest that dysregulated hemostasis may represent a novel therapeutic target in malaria-compromised pregnancies.

A randomized controlled Phase Ib trial of the malaria vaccine candidate GMZ2 in African children

DEFF Research Database (Denmark)

Bélard, Sabine; Issifou, Saadou; Hounkpatin, Aurore B

2011-01-01

GMZ2 is a fusion protein of Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate rich protein (GLURP) that mediates an immune response against the blood stage of the parasite. Two previous phase I clinical trials, one in naïve European adults and one in malaria-exposed Gabonese ...... adults showed that GMZ2 was well tolerated and immunogenic. Here, we present data on safety and immunogenicity of GMZ2 in one to five year old Gabonese children, a target population for future malaria vaccine efficacy trials....

How well are malaria maps used to design and finance malaria control in Africa?

Science.gov (United States)

Omumbo, Judy A; Noor, Abdisalan M; Fall, Ibrahima S; Snow, Robert W

2013-01-01

Rational decision making on malaria control depends on an understanding of the epidemiological risks and control measures. National Malaria Control Programmes across Africa have access to a range of state-of-the-art malaria risk mapping products that might serve their decision-making needs. The use of cartography in planning malaria control has never been methodically reviewed. An audit of the risk maps used by NMCPs in 47 malaria endemic countries in Africa was undertaken by examining the most recent national malaria strategies, monitoring and evaluation plans, malaria programme reviews and applications submitted to the Global Fund. The types of maps presented and how they have been used to define priorities for investment and control was investigated. 91% of endemic countries in Africa have defined malaria risk at sub-national levels using at least one risk map. The range of risk maps varies from maps based on suitability of climate for transmission; predicted malaria seasons and temperature/altitude limitations, to representations of clinical data and modelled parasite prevalence. The choice of maps is influenced by the source of the information. Maps developed using national data through in-country research partnerships have greater utility than more readily accessible web-based options developed without inputs from national control programmes. Although almost all countries have stratification maps, only a few use them to guide decisions on the selection of interventions allocation of resources for malaria control. The way information on the epidemiology of malaria is presented and used needs to be addressed to ensure evidence-based added value in planning control. The science on modelled impact of interventions must be integrated into new mapping products to allow a translation of risk into rational decision making for malaria control. As overseas and domestic funding diminishes, strategic planning will be necessary to guide appropriate financing for malaria

How well are malaria maps used to design and finance malaria control in Africa?

Directory of Open Access Journals (Sweden)

Judy A Omumbo

Full Text Available Rational decision making on malaria control depends on an understanding of the epidemiological risks and control measures. National Malaria Control Programmes across Africa have access to a range of state-of-the-art malaria risk mapping products that might serve their decision-making needs. The use of cartography in planning malaria control has never been methodically reviewed.An audit of the risk maps used by NMCPs in 47 malaria endemic countries in Africa was undertaken by examining the most recent national malaria strategies, monitoring and evaluation plans, malaria programme reviews and applications submitted to the Global Fund. The types of maps presented and how they have been used to define priorities for investment and control was investigated.91% of endemic countries in Africa have defined malaria risk at sub-national levels using at least one risk map. The range of risk maps varies from maps based on suitability of climate for transmission; predicted malaria seasons and temperature/altitude limitations, to representations of clinical data and modelled parasite prevalence. The choice of maps is influenced by the source of the information. Maps developed using national data through in-country research partnerships have greater utility than more readily accessible web-based options developed without inputs from national control programmes. Although almost all countries have stratification maps, only a few use them to guide decisions on the selection of interventions allocation of resources for malaria control.The way information on the epidemiology of malaria is presented and used needs to be addressed to ensure evidence-based added value in planning control. The science on modelled impact of interventions must be integrated into new mapping products to allow a translation of risk into rational decision making for malaria control. As overseas and domestic funding diminishes, strategic planning will be necessary to guide appropriate

How Well Are Malaria Maps Used to Design and Finance Malaria Control in Africa?

Science.gov (United States)

Omumbo, Judy A.; Noor, Abdisalan M.; Fall, Ibrahima S.; Snow, Robert W.

2013-01-01

Introduction Rational decision making on malaria control depends on an understanding of the epidemiological risks and control measures. National Malaria Control Programmes across Africa have access to a range of state-of-the-art malaria risk mapping products that might serve their decision-making needs. The use of cartography in planning malaria control has never been methodically reviewed. Materials and Methods An audit of the risk maps used by NMCPs in 47 malaria endemic countries in Africa was undertaken by examining the most recent national malaria strategies, monitoring and evaluation plans, malaria programme reviews and applications submitted to the Global Fund. The types of maps presented and how they have been used to define priorities for investment and control was investigated. Results 91% of endemic countries in Africa have defined malaria risk at sub-national levels using at least one risk map. The range of risk maps varies from maps based on suitability of climate for transmission; predicted malaria seasons and temperature/altitude limitations, to representations of clinical data and modelled parasite prevalence. The choice of maps is influenced by the source of the information. Maps developed using national data through in-country research partnerships have greater utility than more readily accessible web-based options developed without inputs from national control programmes. Although almost all countries have stratification maps, only a few use them to guide decisions on the selection of interventions allocation of resources for malaria control. Conclusion The way information on the epidemiology of malaria is presented and used needs to be addressed to ensure evidence-based added value in planning control. The science on modelled impact of interventions must be integrated into new mapping products to allow a translation of risk into rational decision making for malaria control. As overseas and domestic funding diminishes, strategic planning will be

Reduction in malaria prevalence and increase in malaria awareness in endemic districts of Bangladesh.

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Alam, Mohammad Shafiul; Kabir, Mohammad Moktadir; Hossain, Mohammad Sharif; Naher, Shamsun; Ferdous, Nur E Naznin; Khan, Wasif Ali; Mondal, Dinesh; Karim, Jahirul; Shamsuzzaman, A K M; Ahmed, Be-Nazir; Islam, Akramul; Haque, Rashidul

2016-11-11

Malaria is endemic in 13 districts of Bangladesh. A baseline malaria prevalence survey across the endemic districts of Bangladesh was conducted in 2007, when the prevalence was reported around 39.7 per 1000 population. After two rounds of Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM)-funded intervention by the National Malaria Control Programme (NMCP) and a BRAC-led NGO consortium, a follow-up survey was conducted across the malaria-endemic districts of Bangladesh to measure the change in prevalence rate and in people's knowledge of malaria. The survey was carried out from August to November 2013 in 70 upazilas (sub-districts) of 13 malaria-endemic districts of Bangladesh, following the same multi-stage cluster sampling design and the same number of households enrolled during the baseline prevalence survey in 2007, to collect 9750 randomly selected blood samples. For on-the-spot diagnosis of malaria, a rapid diagnostic test was used. The household head or eldest person available was interviewed using a pre-coded structured questionnaire to collect data on the knowledge and awareness of malaria in the household. Based on a weighted calculation, the overall malaria prevalence was found to be 1.41 per 1000 population. The proportion of Plasmodium falciparum mono-infection was 77.78% while both Plasmodium vivax mono-infection and mixed infection of the two species were found to be 11.11%. Bandarban had the highest prevalence (6.67 per 1000 population). Knowledge of malaria signs, symptoms and mode of transmission were higher in the follow-up survey (97.26%) than the baseline survey. Use of bed nets for prevention of malaria was found to be high (90.15%) at respondent level. People's knowledge of selected parameters increased significantly during the follow-up survey compared to the baseline survey conducted in 2007. A reduced prevalence rate of malaria and increased level of knowledge were observed in the present malaria prevalence survey in Bangladesh.

Thrombocytopenia in malaria: can platelet counts differentiate malaria from other infections

International Nuclear Information System (INIS)

Arshad, A.R.

2015-01-01

To determine the accuracy of thrombocytopenia as a diagnostic marker for malaria. Study Design: Cross-sectional study. Place and Duration of Study: Department of Medicine, 1 Mountain Medical Battalion (Bagh, Azad Kashmir) from July to September 2013. Methodology: Adult patients presenting with a short history of fever without any localizing symptoms or signs were included. Exclusion criteria included patients with fever of > 7 days duration, those in whom an underlying diagnosis could be easily confirmed on the basis of history and physical examination, those on antibiotics/ antimalarials or antiplatelet agents and patients with Dengue fever. Platelet counts in venous whole blood samples were analysed with Sysmex KX-21 Haematology analyzer. Thick and thin peripheral blood smears were then prepared and examined for malarial parasites. Diagnosis of malaria was established on the basis of smear findings. Results: There were 245 patients in total. Out of the 109 patients with thrombocytopenia, 61 had vivax malaria. Platelets count was normal in 136 patients, including 4 with vivax malaria. Falciparum malaria was not seen in any patient. All cases with malaria were uncomplicated. Various measures of accuracy thus calculated were sensitivity 93.85%, specificity 73.33%, positive predictive value 55.96%, negative predictive value 97.06%, positive likelihood ratio of 3.52, negative likelihood ratio of 0.08, diagnostic odds ratio 41.94 and diagnostic accuracy of 78.78%. Conclusion: Thrombocytopenia has an excellent sensitivity and a very good specificity for vivax malaria. Normal platelet counts provide very strong evidence against malaria as the etiology of fever without a focus. (author)

Safety and immunogenicity of an AMA1 malaria vaccine in Malian children: results of a phase 1 randomized controlled trial.

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Mahamadou A Thera

2010-02-01

Full Text Available The objective was to evaluate the safety and immunogenicity of the AMA1-based malaria vaccine FMP2.1/AS02(A in children exposed to seasonal falciparum malaria.A Phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02(A is a recombinant protein (FMP2.1 based on apical membrane antigen 1 (AMA1 from the 3D7 clone of P. falciparum, formulated in the Adjuvant System AS02(A. The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert. One hundred healthy Malian children aged 1-6 years were recruited into 3 cohorts and randomized to receive either 10 microg FMP2.1 in 0.1 mL AS02(A, or 25 microg FMP2.1 in 0.25 mL AS02(A, or 50 microg FMP2.1 50 microg in 0.5 mL AS02(A, or rabies vaccine. Three doses of vaccine were given at 0, 1 and 2 months, and children were followed for 1 year. Solicited symptoms were assessed for 7 days and unsolicited symptoms for 30 days after each vaccination. Serious adverse events were assessed throughout the study. Transient local pain and swelling were common and more frequent in all malaria vaccine dosage groups than in the comparator group, but were acceptable to parents of participants. Levels of anti-AMA1 antibodies measured by ELISA increased significantly (at least 100-fold compared to baseline in all 3 malaria vaccine groups, and remained high during the year of follow up.The FMP2.1/AS02(A vaccine had a good safety profile, was well-tolerated, and induced high and sustained antibody levels in malaria-exposed children. This malaria vaccine is being evaluated in a Phase 2 efficacy trial in children at this site.ClinicalTrials.gov NCT00358332 [NCT00358332].

Use of proxy measures in estimating socioeconomic inequalities in malaria prevalence.

Science.gov (United States)

Somi, Masha F; Butler, James R; Vahid, Farshid; Njau, Joseph D; Kachur, S P; Abdulla, Salim

2008-03-01

To present and compare socioeconomic status (SES) rankings of households using consumption and an asset-based index as two alternative measures of SES; and to compare and evaluate the performance of these two measures in multivariate analyses of the socioeconomic gradient in malaria prevalence. Data for the study come from a survey of 557 households in 25 study villages in Tanzania in 2004. Household SES was determined using consumption and an asset-based index calculated using Principal Components Analysis on a set of household variables. In multivariate analyses of malaria prevalence, we also used two other measures of disease prevalence: parasitaemia and self-report of malaria or fever in the 2 weeks before interview. Household rankings based on the two measures of SES differ substantially. In multivariate analyses, there was a statistically significant negative association between both measures of SES and parasitaemia but not between either measure of SES and self-reported malaria. Age of individual, use of a mosquito net, and wall construction were negatively and significantly associated with parasitaemia, whilst roof construction was positively associated with parasitaemia. Only age remained significant when malaria self-report was used as the measure of disease prevalence. An asset index is an effective alternative to consumption in measuring the socioeconomic gradient in malaria parasitaemia, but self-report may be an unreliable measure of malaria prevalence for this purpose.

Observation of Blood Donor-Recipient Malaria Parasitaemia Patterns in a Malaria Endemic Region.

Science.gov (United States)

Faruk, Jamilu Abdullahi; Ogunrinde, Gboye Olufemi; Mamman, Aisha Indo

2017-01-01

Asymptomatic malaria parasitaemia has been documented in donor blood in West Africa. However, donated blood is not routinely screened for malaria parasites (MPs). The present study therefore aimed to document the frequency of blood transfusion-induced donor-recipient malaria parasitaemia patterns, in children receiving blood transfusion in a tertiary health-centre. A cross-sectional, observational study involving 140 children receiving blood transfusion was carried out. Blood donor units and patients' blood samples were obtained, for the determination of malaria parasites (MPs). Giemsa staining technique was used to determine the presence of malaria parasitaemia. Malaria parasites were detected in 7% of donor blood and in 8.3% of the recipients' pretransfusion blood. The incidence of posttransfusion MPs was 3%, but none of these were consistent with blood transfusion-induced malaria, as no child with posttransfusion parasitaemia was transfused with parasitized donor blood. Majority of the blood transfusions (89.4%) had no MPs in either donors or recipients, while 6.8% had MPs in both donors and recipients, with the remaining 3.8% showing MPs in recipients alone. In conclusion, the incidence of posttransfusion malaria parasitaemia appears low under the prevailing circumstances.

Malaria and Tropical Travel

Centers for Disease Control (CDC) Podcasts

Malaria is a serious mosquito-borne disease that can lead to death. This podcast discusses malaria risk when traveling to tropical areas, as well as how to protect yourself and your family from malaria infection.

Sixth Africa malaria day in 2006: how far have we come after the Abuja Declaration?

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Wanga Charles L

2006-11-01

Full Text Available Abstract Each year on the 25th April Africa and the rest of the world commemorate Africa Malaria Day as was agreed upon at the African Summit on Roll Back Malaria held in Abuja, Nigeria on 25th April 2000. The summit also called upon the United Nations to declare the period 2001–2010 a decade for malaria. The 1st Africa Malaria Day was commemorated with the theme "Communities Play a Central Role in Tackling Malaria". The 6th Africa Malaria Day was observed in 2006 with the theme "Get Your ACT Together" and the slogan "Universal Access to Effective Malaria Treatment is a Human Right". This article by the Secretariat of the Multilateral Initiative on Malaria (MIM was also part of the commemorations for the day. MIM was founded in 1997 as an alliance of institutions and individuals concerned with the malaria problem, and aiming at maximizing the impact of scientific research on malaria through strengthening African research capacity and coordinated global collaboration. The MIM Secretariat has been hosted in rotation by the founding institutions, and is being hosted for the first time in Africa by the African Malaria Network Trust (AMANET in Dar es Salaam, Tanzania. This article reviews the malaria situation in Africa six years after the Abuja Declaration, highlighting the disease burden trends, failures, achievements, challenges, and the way forward.

Malaria in Brazil: what happens outside the Amazonian endemic region.

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de Pina-Costa, Anielle; Brasil, Patrícia; Di Santi, Sílvia Maria; de Araujo, Mariana Pereira; Suárez-Mutis, Martha Cecilia; Santelli, Ana Carolina Faria e Silva; Oliveira-Ferreira, Joseli; Lourenço-de-Oliveira, Ricardo; Daniel-Ribeiro, Cláudio Tadeu

2014-08-01

Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation's territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation's malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013). The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon) or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex). The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites that seem to be (or

Malaria in Brazil: what happens outside the Amazonian endemic region

Directory of Open Access Journals (Sweden)

Anielle de Pina-Costa

2014-08-01

Full Text Available Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation’s territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation’s malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013. The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex. The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites

Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals

DEFF Research Database (Denmark)

Lizeng, Q; Nilsson, C; Sourial, S

2004-01-01

Links Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals.Lizeng Q, Nilsson C, Sourial S, Andersson S, Larsen O, Aaby P, Ehnlund M, Bjorling E. Research Center, South Hospital, Stockholm, Sweden. The mechanisms behind...... the resistance to human immunodeficiency virus type 2 (HIV-2) infection are still not fully understood. In the present study, we explored the HIV-2-specific humoral serum immunoglobulin A (IgA) immune response in HIV-2-exposed IgG-seronegative (EGSN) individuals. Serum samples from heterosexual EGSN individuals...... and their known HIV-2-infected partners, as well as controls originating from Guinea-Bissau in Africa, were studied. Antibody reactivity to native and recombinant envelope glycoproteins was investigated, and the capacity of purified serum IgA to neutralize HIV-2(SBL6669) was tested. Our results showed that 16...

Explaining variance of avian malaria infection in the wild: the importance of host density, habitat, individual life-history and oxidative stress.

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Isaksson, Caroline; Sepil, Irem; Baramidze, Vladimer; Sheldon, Ben C

2013-04-08

Avian malaria (Plasmodium sp.) is globally widespread, but considerable variation exists in infection (presence/absence) patterns at small spatial scales. This variation can be driven by variation in ecology, demography, and phenotypic characters, in particular those that influence the host's resistance. Generation of reactive oxygen species (ROS) is one of the host's initial immune responses to combat parasitic invasion. However, long-term ROS exposure can harm the host and the redox response therefore needs to be adjusted according to infection stage and host phenotype. Here we use experimental and correlational approaches to assess the relative importance of host density, habitat composition, individual level variation and redox physiology for Plasmodium infection in a wild population of great tits, Parus major. We found that 36% of the great tit population was infected with Plasmodium (22% P. relictum and 15% P. circumflexum prevalence) and that patterns of infection were Plasmodium species-specific. First, the infection of P. circumflexum was significantly higher in areas with experimental increased host density, whereas variation in P. relictum infection was mainly attributed to age, sex and reproduction. Second, great tit antioxidant responses - total and oxidizied glutathione - showed age- , sex- and Plasmodium species-specific patterns between infected and uninfected individuals, but reactive oxygen metabolites (ROM) showed only a weak explanatory power for patterns of P. relictum infection. Instead ROM significantly increased with Plasmodium parasitaemia. These results identify some key factors that influence Plasmodium infection in wild birds, and provide a potential explanation for the underlying physiological basis of recently documented negative effects of chronic avian malaria on survival and reproductive success.

Proliferation induced by Plasmodium falciparum antigen and interleukin-2 production by lymphocytes isolated from malaria-immune individuals

DEFF Research Database (Denmark)

Theander, T G; Bygbjerg, I C; Jepsen, S

1986-01-01

Affinity-purified Plasmodium falciparum soluble antigens (SPAg) isolated from in vitro cultures of the parasite were shown to be relatively free of nonspecific polyclonal activators. To determine the presence of lymphocytes with specificity against SPAg in the peripheral blood of malaria-immune i......Affinity-purified Plasmodium falciparum soluble antigens (SPAg) isolated from in vitro cultures of the parasite were shown to be relatively free of nonspecific polyclonal activators. To determine the presence of lymphocytes with specificity against SPAg in the peripheral blood of malaria...

Host-parasite interactions and ecology of the malaria parasite-a bioinformatics approach.

Science.gov (United States)

Izak, Dariusz; Klim, Joanna; Kaczanowski, Szymon

2018-04-25

Malaria remains one of the highest mortality infectious diseases. Malaria is caused by parasites from the genus Plasmodium. Most deaths are caused by infections involving Plasmodium falciparum, which has a complex life cycle. Malaria parasites are extremely well adapted for interactions with their host and their host's immune system and are able to suppress the human immune system, erase immunological memory and rapidly alter exposed antigens. Owing to this rapid evolution, parasites develop drug resistance and express novel forms of antigenic proteins that are not recognized by the host immune system. There is an emerging need for novel interventions, including novel drugs and vaccines. Designing novel therapies requires knowledge about host-parasite interactions, which is still limited. However, significant progress has recently been achieved in this field through the application of bioinformatics analysis of parasite genome sequences. In this review, we describe the main achievements in 'malarial' bioinformatics and provide examples of successful applications of protein sequence analysis. These examples include the prediction of protein functions based on homology and the prediction of protein surface localization via domain and motif analysis. Additionally, we describe PlasmoDB, a database that stores accumulated experimental data. This tool allows data mining of the stored information and will play an important role in the development of malaria science. Finally, we illustrate the application of bioinformatics in the development of population genetics research on malaria parasites, an approach referred to as reverse ecology.

A SIMPLIFIED MODEL FOR PREDICTING MALARIA ENTOMOLOGIC INOCULATION RATES BASED ON ENTOMOLOGIC AND PARASITOLOGIC PARAMETERS RELEVANT TO CONTROL

OpenAIRE

KILLEEN, GERRY F.; McKENZIE, F. ELLIS; FOY, BRIAN D.; SCHIEFFELIN, CATHERINE; BILLINGSLEY, PETER F.; BEIER, JOHN C.

2000-01-01

Malaria transmission intensity is modeled from the starting perspective of individual vector mosquitoes and is expressed directly as the entomologic inoculation rate (EIR). The potential of individual mosquitoes to transmit malaria during their lifetime is presented graphically as a function of their feeding cycle length and survival, human biting preferences, and the parasite sporogonic incubation period. The EIR is then calculated as the product of 1) the potential of individual vectors to ...

Reduced risk of uncomplicated malaria episodes in children with a+-thalassemia in northeastern Tanzania

DEFF Research Database (Denmark)

Enevold, Anders; Lusingu, John P; Mmbando, Bruno

2008-01-01

the susceptibility to uncomplicated malaria. We compared the risk of suffering from febrile, uncomplicated malaria between individuals carrying three common RBC polymorphisms (sickle cell trait, alpha(+)-thalassemia, and glucose-6-phosphate-dehydrogenase deficiency) and controls. The study was performed in an area...... measured with flow cytometry and ELISA assays, respectively. Regression analyses showed that alpha(+)-thalassemia was associated with a reduced risk of uncomplicated malaria episodes and that this advantageous effect seemed to be more predominant in children older than 5 years of age, but was independent...

Measurement of ex vivo ELISpot interferon-gamma recall responses to Plasmodium falciparum AMA1 and CSP in Ghanaian adults with natural exposure to malaria.

Science.gov (United States)

Ganeshan, Harini; Kusi, Kwadwo A; Anum, Dorothy; Hollingdale, Michael R; Peters, Bjoern; Kim, Yohan; Tetteh, John K A; Ofori, Michael F; Gyan, Ben A; Koram, Kwadwo A; Huang, Jun; Belmonte, Maria; Banania, Jo Glenna; Dodoo, Daniel; Villasante, Eileen; Sedegah, Martha

2016-02-01

Malaria eradication requires a concerted approach involving all available control tools, and an effective vaccine would complement these efforts. An effective malaria vaccine should be able to induce protective immune responses in a genetically diverse population. Identification of immunodominant T cell epitopes will assist in determining if candidate vaccines will be immunogenic in malaria-endemic areas. This study therefore investigated whether class I-restricted T cell epitopes of two leading malaria vaccine antigens, Plasmodium falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1), could recall T cell interferon-γ responses from naturally exposed subjects using ex vivo ELISpot assays. Thirty-five subjects aged between 24 and 43 years were recruited from a malaria-endemic urban community of Ghana in 2011, and their peripheral blood mononuclear cells (PBMCs) were tested in ELISpot IFN-γ assays against overlapping 15mer peptide pools spanning the entire CSP and AMA1 antigens, and 9-10mer peptide epitope mixtures that included previously identified and/or predicted human leukocyte antigen (HLA) class 1-restricted epitopes from same two antigens. For CSP, 26 % of subjects responded to at least one of the nine 15mer peptide pools whilst 17 % responded to at least one of the five 9-10mer HLA-restricted epitope mixtures. For AMA1, 63 % of subjects responded to at least one of the 12 AMA1 15mer peptide pools and 51 % responded to at least one of the six 9-10mer HLA-restricted epitope mixtures. Following analysis of data from the two sets of peptide pools, along with bioinformatics predictions of class I-restricted epitopes and the HLA supertypes expressed by a subset of study subjects, peptide pools that may contain epitopes recognized by multiple HLA supertypes were identified. Collectively, these results suggest that natural transmission elicits ELISpot IFN-γ activities to class 1-restricted epitopes that are largely HLA-promiscuous. These

The effect of daily co-trimoxazole prophylaxis on natural development of antibody-mediated immunity against P. falciparum malaria infection in HIV-exposed uninfected Malawian children.

Science.gov (United States)

Longwe, Herbert; Jambo, Kondwani C; Phiri, Kamija S; Mbeye, Nyanyiwe; Gondwe, Thandile; Hall, Tom; Tetteh, Kevin K A; Drakeley, Chris; Mandala, Wilson L

2015-01-01

Co-trimoxazole prophylaxis, currently recommended in HIV-exposed, uninfected (HEU) children as protection against opportunistic infections, also has some anti-malarial efficacy. We determined whether daily co-trimoxazole prophylaxis affects the natural development of antibody-mediated immunity to blood-stage Plasmodium falciparum malaria infection. Using an enzyme-linked immunosorbent assay, we measured antibodies to 8 Plasmodium falciparum antigens (AMA-1, MSP-119, MSP-3, PfSE, EBA-175RII, GLURP R0, GLURP R2 and CSP) in serum samples from 33 HEU children and 31 HIV-unexposed, uninfected (HUU) children, collected at 6, 12 and 18 months of age. Compared to HIV-uninfected children, HEU children had significantly lower levels of specific IgG against AMA-1 at 6 months (p = 0.001), MSP-119 at 12 months (p = 0.041) and PfSE at 6 months (p = 0.038), 12 months (p = 0.0012) and 18 months (p = 0.0097). No differences in the IgG antibody responses against the rest of the antigens were observed between the two groups at all time points. The breadth of specificity of IgG response was reduced in HEU children compared to HUU children during the follow up period. Co-trimoxazole prophylaxis seems to reduce IgG antibody responses to P. falciparum blood stage antigens, which could be as a result of a reduction in exposure of those children under this regime. Although antibody responses were regarded as markers of exposure in this study, further studies are required to establish whether these responses are correlated in any way to clinical immunity to malaria.

Relationship between the entomologic inoculation rate and the force of infection for Plasmodium falciparum malaria.

Science.gov (United States)

Smith, Thomas; Maire, Nicolas; Dietz, Klaus; Killeen, Gerry F; Vounatsou, Penelope; Molineaux, Louis; Tanner, Marcel

2006-08-01

We propose a stochastic model for the relationship between the entomologic inoculation rate (EIR) for Plasmodium falciparum malaria and the force of infection in endemic areas. The model incorporates effects of increased exposure to mosquito bites as a result of the growth in body surface area with the age of the host, naturally acquired pre-erythrocytic immunity, and the reduction in the proportion of entomologically assessed inoculations leading to infection, as the EIR increases. It is fitted to multiple datasets from field studies of the relationship between malaria infection and the EIR. We propose that this model can account for non-monotonic relationships between the age of the host and the parasite prevalence and incidence of disease. It provides a parsimonious explanation for the faster acquisition of natural immunity in adults than in children exposed to high EIRs. This forms one component of a new stochastic model for the entire transmission cycle of P. falciparum that we have derived to estimate the potential epidemiologic impact of malaria vaccines and other malaria control interventions.

A review of mixed malaria species infections in anopheline mosquitoes

Directory of Open Access Journals (Sweden)

Day Nicholas PJ

2011-08-01

Full Text Available Abstract Background In patients with malaria mixed species infections are common and under reported. In PCR studies conducted in Asia mixed infection rates often exceed 20%. In South-East Asia, approximately one third of patients treated for falciparum malaria experience a subsequent Plasmodium vivax infection with a time interval suggesting relapse. It is uncertain whether the two infections are acquired simultaneously or separately. To determine whether mixed species infections in humans are derived from mainly from simultaneous or separate mosquito inoculations the literature on malaria species infection in wild captured anopheline mosquitoes was reviewed. Methods The biomedical literature was searched for studies of malaria infection and species identification in trapped wild mosquitoes and artificially infected mosquitoes. The study location and year, collection methods, mosquito species, number of specimens, parasite stage examined (oocysts or sporozoites, and the methods of parasite detection and speciation were tabulated. The entomological results in South East Asia were compared with mixed infection rates documented in patients in clinical studies. Results In total 63 studies were identified. Individual anopheline mosquitoes were examined for different malaria species in 28 of these. There were 14 studies from Africa; four with species evaluations in individual captured mosquitoes (SEICM. One study, from Ghana, identified a single mixed infection. No mixed infections were identified in Central and South America (seven studies, two SEICM. 42 studies were conducted in Asia and Oceania (11 from Thailand; 27 SEICM. The proportion of anophelines infected with Plasmodium falciparum parasites only was 0.51% (95% CI: 0.44 to 0.57%, for P. vivax only was 0.26% (95% CI: 0.21 to 0.30%, and for mixed P. falciparum and P. vivax infections was 0.036% (95% CI: 0.016 to 0.056%. The proportion of mixed infections in mosquitoes was significantly higher

International funding for malaria control in relation to populations at risk of stable Plasmodium falciparum transmission.

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Robert W Snow

2008-07-01

Full Text Available The international financing of malaria control has increased significantly in the last ten years in parallel with calls to halve the malaria burden by the year 2015. The allocation of funds to countries should reflect the size of the populations at risk of infection, disease, and death. To examine this relationship, we compare an audit of international commitments with an objective assessment of national need: the population at risk of stable Plasmodium falciparum malaria transmission in 2007.The national distributions of populations at risk of stable P. falciparum transmission were projected to the year 2007 for each of 87 P. falciparum-endemic countries. Systematic online- and literature-based searches were conducted to audit the international funding commitments made for malaria control by major donors between 2002 and 2007. These figures were used to generate annual malaria funding allocation (in US dollars per capita population at risk of stable P. falciparum in 2007. Almost US$1 billion are distributed each year to the 1.4 billion people exposed to stable P. falciparum malaria risk. This is less than US$1 per person at risk per year. Forty percent of this total comes from the Global Fund to Fight AIDS, Tuberculosis and Malaria. Substantial regional and national variations in disbursements exist. While the distribution of funds is found to be broadly appropriate, specific high population density countries receive disproportionately less support to scale up malaria control. Additionally, an inadequacy of current financial commitments by the international community was found: under-funding could be from 50% to 450%, depending on which global assessment of the cost required to scale up malaria control is adopted.Without further increases in funding and appropriate targeting of global malaria control investment it is unlikely that international goals to halve disease burdens by 2015 will be achieved. Moreover, the additional financing

Targeting imported malaria through social networks: a potential strategy for malaria elimination in Swaziland.

Science.gov (United States)

Koita, Kadiatou; Novotny, Joseph; Kunene, Simon; Zulu, Zulizile; Ntshalintshali, Nyasatu; Gandhi, Monica; Gosling, Roland

2013-06-27

Swaziland has made great progress towards its goal of malaria elimination by 2015. However, malaria importation from neighbouring high-endemic Mozambique through Swaziland's eastern border remains a major factor that could prevent elimination from being achieved. In order to reach elimination, Swaziland must rapidly identify and treat imported malaria cases before onward transmission occurs. A nationwide formative assessment was conducted over eight weeks to determine if the imported cases of malaria identified by the Swaziland National Malaria Control Programme could be linked to broader social networks and to explore methods to access these networks. Using a structured format, interviews were carried out with malaria surveillance agents (6), health providers (10), previously identified imported malaria cases (19) and people belonging to the networks identified through these interviews (25). Most imported malaria cases were Mozambicans (63%, 12/19) making a living in Swaziland and sustaining their families in Mozambique. The majority of imported cases (73%, 14/19) were labourers and self-employed contractors who travelled frequently to Mozambique to visit their families and conduct business. Social networks of imported cases with similar travel patterns were identified through these interviews. Nearly all imported cases (89%, 17/19) were willing to share contact information to enable network members to be interviewed. Interviews of network members and key informants revealed common congregation points, such as the urban market places in Manzini and Malkerns, as well as certain bus stations, where people with similar travel patterns and malaria risk behaviours could be located and tested for malaria. This study demonstrated that imported cases of malaria belonged to networks of people with similar travel patterns. This study may provide novel methods for screening high-risk groups of travellers using both snowball sampling and time-location sampling of networks to

Malaria chemotherapy.

Science.gov (United States)

Winstanley, Peter; Ward, Stephen

2006-01-01

Most malaria control strategies today depend on safe and effective drugs, as they have done for decades. But sensitivity to chloroquine, hitherto the workhorse of malaria chemotherapy, has rapidly declined throughout the tropics since the 1980s, and this drug is now useless in many high-transmission areas. New options for resource-constrained governments are few, and there is growing evidence that the burden from malaria has been increasing, as has malaria mortality in Africa. In this chapter, we have tried to outline the main pharmacological properties of current drugs, and their therapeutic uses and limitations. We have summarised the ways in which these drugs are employed, both in the formal health sector and in self-medication. We have briefly touched on the limitations of current drug development, but have tried to pick out a few promising drugs that are under development. Given that Plasmodium falciparum is the organism that kills, and that has developed multi-drug resistance, we have tended to focus upon it. Similarly, given that around 90% of global mortality from malaria occurs in Africa, there is the tendency to dwell on this continent. We give no apology for placing our emphasis upon the use of antimalarial drugs in endemic populations rather than their use for prophylaxis in travellers.

A global map of dominant malaria vectors

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Sinka Marianne E

2012-04-01

Full Text Available Abstract Background Global maps, in particular those based on vector distributions, have long been used to help visualise the global extent of malaria. Few, however, have been created with the support of a comprehensive and extensive evidence-based approach. Methods Here we describe the generation of a global map of the dominant vector species (DVS of malaria that makes use of predicted distribution maps for individual species or species complexes. Results Our global map highlights the spatial variability in the complexity of the vector situation. In Africa, An. gambiae, An. arabiensis and An. funestus are co-dominant across much of the continent, whereas in the Asian-Pacific region there is a highly complex situation with multi-species coexistence and variable species dominance. Conclusions The competence of the mapping methodology to accurately portray DVS distributions is discussed. The comprehensive and contemporary database of species-specific spatial occurrence (currently available on request will be made directly available via the Malaria Atlas Project (MAP website from early 2012.

Individual and household factors associated with ownership of long-lasting insecticidal nets and malaria infection in south-central Ethiopia: a case-control study.

Science.gov (United States)

Deressa, Wakgari

2017-10-06

A recent considerable decline in malaria morbidity and mortality in Ethiopia is likely to be followed by changes in the practice of effective preventive measures and malaria risk factors. This study aimed to identify determinants of long-lasting insecticidal nets (LLINs) ownership and risk of malaria infection. A matched case-control study of 191 case and 377 control households was conducted between October 2014 and November 2015 in Adami Tullu district in south-central Ethiopia. Cases were microscopy or rapid diagnostic test confirmed malaria patients identified at three health centers and nine health posts, and matched on age with two neighbourhood controls. Information was collected on socio-demographic factors, house structure, knowledge on malaria and ownership of LLINs. The logistic regression model was used to determine predictors of LLINs ownership and malaria infection. All cases were infections due to either Plasmodium falciparum (71.2%) or Plasmodium vivax (28.8%). About 31% of the study households had at least one LLINs. Significant determinants of LLINs ownership were household's head malaria knowledge [adjusted odds ratio (AOR) = 2.47, 95% confidence interval (CI) 1.44-4.22], educational status [read and write (AOR = 6.88, 95% CI 2.30-20.55), primary education or higher (AOR = 5.40, 95% CI 1.57-18.55)], farmer respondent (AOR = 0.35, 95% CI 0.17-0.76), having ≥ 3 sleeping areas (AOR = 6.71, 95% CI 2.40-18.77) and corrugated roof type (AOR = 2.49, 95% CI 1.36-4.58). This study was unable to identify important risk factors of malaria infection with regard to sex, household wealth index, house structure, ownership of LLINs, keeping livestock inside house, staying overnight outdoor or having malaria during the last 6 months. Household socio-economic status, educational status and knowledge on malaria were important predictors of LLINs ownership. Households with farmer respondents were less likely to own LLINs. Addressing these factors

Biosphere Dose Conversion Factors for Reasonably Maximally Exposed Individual and Average Member of Critical Group

International Nuclear Information System (INIS)

K. Montague

2000-01-01

The purpose of this calculation is to develop additional Biosphere Dose Conversion Factors (BDCFs) for a reasonably maximally exposed individual (RMEI) for the periods 10,000 years and 1,000,000 years after the repository closure. In addition, Biosphere Dose Conversion Factors for the average member of a critical group are calculated for those additional radionuclides postulated to reach the environment during the period after 10,000 years and up to 1,000,000 years. After the permanent closure of the repository, the engineered systems within the repository will eventually lose their abilities to contain radionuclide inventory, and the radionuclides will migrate through the geosphere and eventually enter the local water table moving toward inhabited areas. The primary release scenario is a groundwater well used for drinking water supply and irrigation, and this calculation takes these postulated releases and follows them through various pathways until they result in a dose to either a member of critical group or a reasonably maximally exposed individual. The pathways considered in this calculation include inhalation, ingestion, and direct exposure

Shifting suitability for malaria vectors across Africa with warming climates

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Peterson A Townsend

2009-05-01

Full Text Available Abstract Background Climates are changing rapidly, producing warm climate conditions globally not previously observed in modern history. Malaria is of great concern as a cause of human mortality and morbidity, particularly across Africa, thanks in large part to the presence there of a particularly competent suite of mosquito vector species. Methods I derive spatially explicit estimates of human populations living in regions newly suitable climatically for populations of two key Anopheles gambiae vector complex species in Africa over the coming 50 years, based on ecological niche model projections over two global climate models, two scenarios of climate change, and detailed spatial summaries of human population distributions. Results For both species, under all scenarios, given the changing spatial distribution of appropriate conditions and the current population distribution, the models predict a reduction of 11.3–30.2% in the percentage of the overall population living in areas climatically suitable for these vector species in coming decades, but reductions and increases are focused in different regions: malaria vector suitability is likely to decrease in West Africa, but increase in eastern and southern Africa. Conclusion Climate change effects on African malaria vectors shift their distributional potential from west to east and south, which has implications for overall numbers of people exposed to these vector species. Although the total is reduced, malaria is likely to pose novel public health problems in areas where it has not previously been common.

Malaria Matters

Centers for Disease Control (CDC) Podcasts

2008-04-18

This podcast gives an overview of malaria, including prevention and treatment, and what CDC is doing to help control and prevent malaria globally.  Created: 4/18/2008 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 4/18/2008.

No evidence of association between HIV-1 and malaria in populations with low HIV-1 prevalence.

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Diego F Cuadros

Full Text Available The geographic overlap between HIV-1 and malaria has generated much interest in their potential interactions. A variety of studies have evidenced a complex HIV-malaria interaction within individuals and populations that may have dramatic effects, but the causes and implications of this co-infection at the population level are still unclear. In a previous publication, we showed that the prevalence of malaria caused by the parasite Plasmodium falciparum is associated with HIV infection in eastern sub-Saharan Africa. To complement our knowledge of the HIV-malaria co-infection, the objective of this work was to assess the relationship between malaria and HIV prevalence in the western region of sub-Saharan Africa.Population-based cross-sectional data were obtained from the HIV/AIDS Demographic and Health Surveys conducted in Burkina Faso, Ghana, Guinea, Mali, Liberia and Cameroon, and the malaria atlas project. Using generalized linear mixed models, we assessed the relationship between HIV-1 and Plasmodium falciparum parasite rate (PfPR adjusting for important socio-economic and biological cofactors. We found no evidence that individuals living in areas with stable malaria transmission (PfPR>0.46 have higher odds of being HIV-positive than individuals who live in areas with PfPR≤0.46 in western sub-Saharan Africa (estimated odds ratio 1.14, 95% confidence interval 0.86-1.50. In contrast, the results suggested that PfPR was associated with being infected with HIV in Cameroon (estimated odds ratio 1.56, 95% confidence interval 1.23-2.00.Contrary to our previous research on eastern sub-Saharan Africa, this study did not identify an association between PfPR and infection with HIV in western sub-Saharan Africa, which suggests that malaria might not play an important role in the spread of HIV in populations where the HIV prevalence is low. Our work highlights the importance of understanding the epidemiologic effect of co-infection and the relevant

A non-inferiority, individually randomized trial of intermittent screening and treatment versus intermittent preventive treatment in the control of malaria in pregnancy

DEFF Research Database (Denmark)

Tagbor, Harry; Cairns, Matthew; Bojang, Kalifa

2015-01-01

BACKGROUND: The efficacy of intermittent preventive treatment for malaria with sulfadoxine-pyrimethamine (IPTp-SP) in pregnancy is threatened in parts of Africa by the emergence and spread of resistance to SP. Intermittent screening with a rapid diagnostic test (RDT) and treatment of positive women...... with malaria parasitemia between routine antenatal clinics (310 vs 182 episodes, rate difference: 49.4 per 1,000 pregnancies [95% CI 30.5, 68.3], but the number of hospital admissions for malaria was similar in the two groups. CONCLUSIONS: Despite low levels of resistance to SP in the study areas, ISTp......-AL performed as well as IPTp-SP. In the absence of an effective alternative medication to SP for IPTp, ISTp-AL is a potential alternative to IPTp in areas where SP resistance is high. It may also have a role in areas where malaria transmission is low and for the prevention of malaria in HIV positive women...

PREVALENCE OF LYMPHATIC FILARIASIS, MALARIA AND SOIL TRANSMITTED HELMINTHIASIS IN A COMMUNITY OF BARDIYA DISTRICT, WESTERN NEPAL.

Science.gov (United States)

Ranjitkar, Samir; Alifrangis, Michael; Adhikari, Madhav; Olsen, Annette; Simonsen, Paul E; Meyrowitsch, Dan Wolf

2014-11-01

Lymphatic filariasis (LF), malaria and soil transmitted helminthiasis (STH) cause major health problems in Nepal, but in spite of this very few stud- ies have been carried out on these parasitic infections in Nepal. A cross sectional survey of all three categories of parasitic infections was carried out in Deuda- kala Village of Bardiya District, western Nepal. A total of 510 individuals aged 5 years and above were examined from finger prick blood for circulating filarial antigen (CFA), malaria antigen using a rapid diagnostic test (RDT), and malaria DNA using a PCR-based assay. In addition, 317 individuals were examined for soil-transmitted helminth (STH) eggs by the Kato-Katz technique. Prevalence of LF, malaria (antigen) and STH infection was 25.1%, 0.6% and 18.3%, respectively. PCR analysis did not detect any additional malaria cases. The prevalence of LF and STH infections differ significantly among different age groups and ethnic communities. The high prevalence of LF in the community studied indicates an immediate need for implementing a mass drug administration program for its control in this particular geographical area of Nepal.

Genetic polymorphism and average life expectancy of exposed individuals and their offspring

International Nuclear Information System (INIS)

Telnov, V.I.; Sotnik, N.V.

2004-01-01

A population-genetic analysis of the average life expectancy (ALE) was performed for nuclear workers at the Mayak Production Association exposed to external and internal radiation over a wide dose range and their off spring. A methodical approach was proposed to determine ALE for individuals with different genotypes and estimate ALE in the population based on genotype distribution. The analysis has revealed significant shifts in the Hp type distribution of genetic markers in the nuclear workers off spring, especially an increased proportion of Hp 2-2 at parents external g-irradiation doses over 2Gy by the conception time

Parasite threshold associated with clinical malaria in areas of different transmission intensities in north eastern Tanzania

DEFF Research Database (Denmark)

Mmbando, Bruno P; Lusingu, John P; Vestergaard, Lasse S

2009-01-01

BACKGROUND: In Sub-Sahara Africa, malaria due to Plasmodium falciparum is the main cause of ill health. Evaluation of malaria interventions, such as drugs and vaccines depends on clinical definition of the disease, which is still a challenge due to lack of distinct malaria specific clinical...... features. Parasite threshold is used in definition of clinical malaria in evaluation of interventions. This however, is likely to be influenced by other factors such as transmission intensity as well as individual level of immunity against malaria. METHODS: This paper describes step function and dose...... response model with threshold parameter as a tool for estimation of parasite threshold for onset of malaria fever in highlands (low transmission) and lowlands (high transmission intensity) strata. These models were fitted using logistic regression stratified by strata and age groups (0-1, 2-3, 4-5, 6...

Recurrent Plasmodium falciparum malaria infections in Kenyan children diminish T-cell immunity to Epstein Barr virus lytic but not latent antigens.

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Cynthia J Snider

Full Text Available Plasmodium falciparum malaria (Pf-malaria and Epstein Barr Virus (EBV infections coexist in children at risk for endemic Burkitt's lymphoma (eBL; yet studies have only glimpsed the cumulative effect of Pf-malaria on EBV-specific immunity. Using pooled EBV lytic and latent CD8+ T-cell epitope-peptides, IFN-γ ELISPOT responses were surveyed three times among children (10 months to 15 years in Kenya from 2002-2004. Prevalence ratios (PR and 95% confidence intervals (CI were estimated in association with Pf-malaria exposure, defined at the district-level (Kisumu: holoendemic; Nandi: hypoendemic and the individual-level. We observed a 46% decrease in positive EBV lytic antigen IFN-γ responses among 5-9 year olds residing in Kisumu compared to Nandi (PR: 0.54; 95% CI: 0.30-0.99. Individual-level analysis in Kisumu revealed further impairment of EBV lytic antigen responses among 5-9 year olds consistently infected with Pf-malaria compared to those never infected. There were no observed district- or individual-level differences between Pf-malaria exposure and EBV latent antigen IFN-γ response. The gradual decrease of EBV lytic antigen but not latent antigen IFN-γ responses after primary infection suggests a specific loss in immunological control over the lytic cycle in children residing in malaria holoendemic areas, further refining our understanding of eBL etiology.

Retinopathy in severe malaria in Ghanaian children - overlap between fundus changes in cerebral and non-cerebral malaria

DEFF Research Database (Denmark)

Essuman, Vera A; Ntim-Amponsah, Christine T; Astrup, Birgitte S

2010-01-01

diagnostic tool. This study was designed to determine the diagnostic usefulness of retinopathy on ophthalmoscopy in severe malaria syndromes: Cerebral malaria (CM) and non-cerebral severe malaria (non-CM), i.e. malaria with respiratory distress (RD) and malaria with severe anaemia (SA), in Ghanaian children...

Malaria resistance | Iyabo | Nigerian Medical Practitioner

African Journals Online (AJOL)

Age and puberty have been found to contribute to malaria resistance. It is expected that knowledge of natural resistance to malaria may aid in developing Vaccines against this deadly disease. Keywords: malaria resistance, puberty, malaria economy, malaria vaccine. Nigerian Medical Practitioner Vol. 49(5) 2006: 133-142 ...

Vector incrimination and effects of antimalarial drugs on malaria transmission and control in the Amazon Basin of Brazil

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T. A. Klein

1992-01-01

Full Text Available World ecosystems differ significantly and a multidisciplinary malaria control approach must be adjusted to meet these requirements. These include a comprehensive understanding of the malaria vectors, their behavior, seasonal distribution and abundance, susceptibility to insecticides (physiological and behavioral, methods to reduce the numbers of human gametocyte carriers through effective health care systems and antimalarial drug treatment, urban malaria transmission versus rural or forest malaria transmission, and the impact of vaccine development. Many malaria vectors are members of species complexes and individual relationship to malaria transmission, seasonal distribution, bitting behavior, etc. is poorly understood. Additionaly, malaria patients are not examined for circulating gametocytes and both falciparum and vivax malaria patients may be highly infective to mosquitoes after treatment with currently used antimalarial drugs. Studies on the physiological and behavioral effects of DDT and other insecticides are inconclusive and need to be evalusted.

The Gates Malaria Partnership: a consortium approach to malaria research and capacity development.

Science.gov (United States)

Greenwood, Brian; Bhasin, Amit; Targett, Geoffrey

2012-05-01

Recently, there has been a major increase in financial support for malaria control. Most of these funds have, appropriately, been spent on the tools needed for effective prevention and treatment of malaria such as insecticide-treated bed nets, indoor residual spraying and artemisinin combination therapy. There has been less investment in the training of the scientists from malaria-endemic countries needed to support these large and increasingly complex malaria control programmes, especially in Africa. In 2000, with support from the Bill & Melinda Gates Foundation, the Gates Malaria Partnership was established to support postgraduate training of African scientists wishing to pursue a career in malaria research. The programme had three research capacity development components: a PhD fellowship programme, a postdoctoral fellowship programme and a laboratory infrastructure programme. During an 8-year period, 36 African PhD students and six postdoctoral fellows were supported, and two research laboratories were built in Tanzania. Some of the lessons learnt during this project--such as the need to improve PhD supervision in African universities and to provide better support for postdoctoral fellows--are now being applied to a successor malaria research capacity development programme, the Malaria Capacity Development Consortium, and may be of interest to other groups involved in improving postgraduate training in health sciences in African universities. © 2012 Blackwell Publishing Ltd.

Assessing the risk of self-diagnosed malaria in urban informal settlements of Nairobi using self-reported morbidity survey

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Mugisha Frederick

2007-05-01

Full Text Available Abstract Background Because of the belief that Nairobi is a low risk zone for malaria, little empirical data exists on malaria risk in the area. The aim of this study was to explore the risk of perceived malaria and some associated factors in Nairobi informal settlements using self-reported morbidity survey. Methods The survey was conducted from May to August 2004 on 7,288 individuals in two informal settlements of Nairobi. Participants were asked to report illnesses they experienced in the past 14 days. Logistic regression was used to estimate the odds of perceived-malaria. The model included variables such as site of residence, age, ethnicity and number of reported symptoms. Results Participants reported 165 illnesses among which malaria was the leading cause (28.1%. The risk of perceived-malaria was significantly higher in Viwandani compared to Korogocho (OR 1.61, 95%CI: 1.10–2.26. Participants in age group 25–39 years had significantly higher odds of perceived-malaria compared to those under-five years (OR 2.07, 95%CI: 1.43–2.98. The Kikuyu had reduced odds of perceived-malaria compared to other ethnic groups. Individuals with five and more symptoms had higher odds compared to those with no symptoms (OR 23.69, 95%CI: 12.98–43.23. Conclusion Malaria was the leading cause of illness as perceived by the residents in the two informal settlements. This was rational as the number of reported symptoms was highly associated with the risk of reporting the illness. These results highlight the need for a more comprehensive assessment of malaria epidemiology in Nairobi to be able to offer evidence-based guidance to policy on malaria in Kenya and particularly in Nairobi.

IgG antibodies to endothelial protein C receptor-binding Cysteine-rich interdomain region domains of Plasmodium falciparum erythrocyte membrane protein 1 are acquired early in life in individuals exposed to malaria

DEFF Research Database (Denmark)

Turner, Louise; Lavstsen, Thomas; Mmbando, Bruno P

2015-01-01

Severe malaria syndromes are precipitated by Plasmodium falciparum parasites binding to endothelial receptors on the vascular lining. This binding is mediated by members of the highly variant P. falciparum erythrocyte membrane protein 1 (PfEMP1) family. We have previously identified a subset of Pf...

Tracing evolutionary relicts of positive selection on eight malaria-related immune genes in mammals.

Science.gov (United States)

Huang, Bing-Hong; Liao, Pei-Chun

2015-07-01

Plasmodium-induced malaria widely infects primates and other mammals. Multiple past studies have revealed that positive selection could be the main evolutionary force triggering the genetic diversity of anti-malaria resistance-associated genes in human or primates. However, researchers focused most of their attention on the infra-generic and intra-specific genome evolution rather than analyzing the complete evolutionary history of mammals. Here we extend previous research by testing the evolutionary link of natural selection on eight candidate genes associated with malaria resistance in mammals. Three of the eight genes were detected to be affected by recombination, including TNF-α, iNOS and DARC. Positive selection was detected in the rest five immunogenes multiple times in different ancestral lineages of extant species throughout the mammalian evolution. Signals of positive selection were exposed in four malaria-related immunogenes in primates: CCL2, IL-10, HO1 and CD36. However, selection signals of G6PD have only been detected in non-primate eutherians. Significantly higher evolutionary rates and more radical amino acid replacement were also detected in primate CD36, suggesting its functional divergence from other eutherians. Prevalent positive selection throughout the evolutionary trajectory of mammalian malaria-related genes supports the arms race evolutionary hypothesis of host genetic response of mammalian immunogenes to infectious pathogens. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Composition of human skin microbiota affects attractiveness to malaria mosquitoes.

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Niels O Verhulst

Full Text Available The African malaria mosquito Anopheles gambiae sensu stricto continues to play an important role in malaria transmission, which is aggravated by its high degree of anthropophily, making it among the foremost vectors of this disease. In the current study we set out to unravel the strong association between this mosquito species and human beings, as it is determined by odorant cues derived from the human skin. Microbial communities on the skin play key roles in the production of human body odour. We demonstrate that the composition of the skin microbiota affects the degree of attractiveness of human beings to this mosquito species. Bacterial plate counts and 16S rRNA sequencing revealed that individuals that are highly attractive to An. gambiae s.s. have a significantly higher abundance, but lower diversity of bacteria on their skin than individuals that are poorly attractive. Bacterial genera that are correlated with the relative degree of attractiveness to mosquitoes were identified. The discovery of the connection between skin microbial populations and attractiveness to mosquitoes may lead to the development of new mosquito attractants and personalized methods for protection against vectors of malaria and other infectious diseases.

Economic burden of malaria on businesses in Ghana: a case for private sector investment in malaria control.

Science.gov (United States)

Nonvignon, Justice; Aryeetey, Genevieve Cecilia; Malm, Keziah L; Agyemang, Samuel Agyei; Aubyn, Vivian N A; Peprah, Nana Yaw; Bart-Plange, Constance N; Aikins, Moses

2016-09-06

Despite the significant gains made globally in reducing the burden of malaria, the disease remains a major public health challenge, especially in sub-Saharan Africa (SSA) including Ghana. There is a significant gap in financing malaria control globally. The private sector could become a significant source of financing malaria control. To get the private sector to appreciate the need to invest in malaria control, it is important to provide evidence of the economic burden of malaria on businesses. The objective of this study, therefore, was to estimate the economic burden on malaria on businesses in Ghana, so as to stimulate the sector's investment in malaria control. Data covering 2012-2014 were collected from 62 businesses sampled from Greater Accra, Ashanti and Western Regions of Ghana, which have the highest concentration of businesses in the country. Data on the cost of businesses' spending on treatment and prevention of malaria in staff and their dependants as well as staff absenteeism due to malaria and expenditure on other health-related activities were collected. Views of business leaders on the effect of malaria on their businesses were also compiled. The analysis was extrapolated to cover 5828 businesses across the country. The results show that businesses in Ghana lost about US$6.58 million to malaria in 2014, 90 % of which were direct costs. A total of 3913 workdays were lost due to malaria in firms in the study sample during the period 2012-2014. Businesses in the study sample spent an average of 0.5 % of the annual corporate returns on treatment of malaria in employees and their dependants, 0.3 % on malaria prevention, and 0.5 % on other health-related corporate social responsibilities. Again business leaders affirmed that malaria affects their businesses' efficiency, employee attendance and productivity and expenses. Finally, about 93 % of business leaders expressed the need private sector investment in malaria control. The economic burden of

Chronic radiation exposure: possibility of studying mutation process in generations based on the established DNA bank of exposed individuals and their offspring

International Nuclear Information System (INIS)

Rusinova, Galina G.; Adamova, Galina V.; Dudchenko, Natalya N.; Azizova, Tamara V.; Kurbatov, Andrey V.

2002-01-01

Data were summarized on the DNA Bank establishment for workers of the Mayak nuclear facility in Southern Ural, who were exposed to different doses of chronic radiation from γ -rays during the first years of the enterprise operations (1948-1958) and their families. Some workers were exposed to combined radiation (external + internal radiation from incorporated 239 Pu). The DNA Bank was established to store the unique genetic material from these individuals and their offspring for future risk estimation of the late consequences of radiation exposure using modern molecular-genetic technologies. Today, DNA Bank contains genetic material from 1,500 individuals and 218 families. The computer database was generated for the DNA Bank. It included individual medical-demographic, occupational descriptions and doses, quantitative and qualitative DNA data. Literature data on radiation-induced genome instability (variability of hypervariable areas) were also analyzed. Prospects of the DNA Bank establishment are also presented. The work is carried out on extension of the DNA Bank of exposed individuals and their offspring

Households' incidence on malaria and expenditures to treat malaria ...

African Journals Online (AJOL)

CONCLUSION: The relationship between expenditure and use of different vector control depends on the geographic location of respondents. People living in the rural areas spend more to have access to malaria control tools. Location of respondent has a positive effect on expenditures and use of malaria control tools.

Historical review: Does falciparum malaria destroy isolated tribal populations?

Science.gov (United States)

Shanks, G Dennis

Many isolated populations of tribal peoples were nearly destroyed when they first contacted infectious diseases particularly respiratory pathogens such as measles and smallpox. Surviving groups have often been found to have declining populations in the face of multiple social and infectious threats. Malaria, especially Plasmodium falciparum, was thought to be a major cause of depopulation in some tribal peoples isolated in tropical jungles. The dynamics of such host parasite interactions is unclear especially since most such populations would have had long histories of exposure to malaria. Three groups are individually reviewed: Meruts of Borneo, Yanomami of Amazonia, Jarawas of the Andaman Islands. The purpose of this review is to examine the role of falciparum malaria in the depopulation of some isolated tribal groups in order to understand what measures, if any, would be likely to prevent such losses. Copyright © 2016 Elsevier Ltd. All rights reserved.

Associations between maternal helminth and malaria infections in pregnancy, and clinical malaria in the offspring

DEFF Research Database (Denmark)

Ndibazza, Juliet; Webb, Emily L; Lule, Swaib

2013-01-01

Background. Helminth and malaria coinfections are common in the tropics. We investigated the hypothesis that prenatal exposure to these parasites might influence susceptibility to infections such as malaria in childhood.Methods. In a birth cohort of 2,345 mother-child pairs in Uganda, maternal...... helminth and malaria infection status was determined during pregnancy, and childhood malaria episodes recorded from birth to age five years. We examined associations between maternal infections and malaria in the offspring.Results. Common maternal infections were hookworm (45%), Mansonella perstans (21......%), Schistosoma mansoni (18%), and Plasmodium falciparum (11%). At age 5 years, 69% of the children were still under follow-up. The incidence of malaria was 34 episodes per 100 child-years, and the mean prevalence of asymptomatic malaria at annual visits was 5.4%. Maternal hookworm and M. perstans infections were...

[Investigation on current situation of malaria blood examinations in township-level hospitals of Nantong City].

Science.gov (United States)

Gui-Sheng, Ding; Cai-Qun, Cao; Ping, Miao; Mei-Fang, Gu; Xiao-Bin, Cao

2016-11-18

To understand the quality of malaria blood examinations in township-level hospitals, so as to provide the evidence for continuing the malaria blood examinations in the stage of post-malaria elimination. A total of 64 township hospitals were investigated and 640 negative malaria blood slides were scored individually according to 10 indicators in "Malaria Elimination Technical Scheme" in 2013 and 2014. The single and multiple indicators were calculated, and the work of blood examinations and situation of technicians were investigated. The data of malaria blood examinations and patient discovery in township hospitals of Nantong City were collected and analyzed during the period of 2011-2014. For the single indicator, 29.5% of the thick blood films did not reach the standard, and 35.8% of thin blood films did not reach the standard. For the multiple indicators, blood slides with more than 4 indicators below the standard (poor quality) accounted for 32.5%. From malaria blood examinations and malaria situation, the number of slides was 194 635 during the period of 2011-2014, and there were no local vivax malaria casesin 4 consecutive years from 2011 to 2014, and local malaria has been effectively controlled in Nantong City. For health facilities where malaria patients initially presented, the township and village level accounted for 16.3%, and county and higher level accounted for 83.7%. The quality of malaria blood examinations in township level hospitals of Nantong City is not high and the microscopic examination has a relatively low efficiency in the discovery of malaria cases. A new model for malaria blood examinations needs to be further explored.

[Current malaria situation in Turkey].

Science.gov (United States)

Gockchinar, T; Kalipsi, S

2001-01-01

Geographically, Turkey is situated in an area where malaria is very risky. The climatic conditions in the region are suitable for the malaria vector to proliferate. Due to agricultural infrastructural changes, GAP and other similar projects, insufficient environmental conditions, urbanization, national and international population moves, are a key to manage malaria control activities. It is estimated that malaria will be a potential danger for Turkey in the forthcoming years. The disease is located largely in south-eastern Anatolia. The Diyarbakir, Batman, Sanliurfa, Siirt, and Mardin districts are the most affected areas. In western districts, like Aydin and Manisa, an increase in the number of indigenous cases can be observed from time to time. This is due to workers moving from malaria districts to western parts to final work. Since these workers cannot be controlled, the population living in these regions get infected from indigenous cases. There were 84,345 malaria cases in 1994 and 82,096 in 1995, they decreased to 60,884 in 1996 and numbered 35,456 in 1997. They accounted for 36,842 and 20,963 in 1998 and 1999, respectively. In Turkey there are almost all cases of P. vivax malaria. There are also P. vivax and P. falciparum malaria cases coming from other countries: There were 321 P. vivax cases, including 2 P. falciparum ones, arriving to Turkey from Iraq in 1995. The P. vivax malaria cases accounted for 229 in 1996, and 67, cases P. vivax including 12 P. falciparum cases, in 1997, and 4 P. vivax cases in 1998 that came from that country. One P. vivax case entered Turkey from Georgia in 1998. The cause of higher incidence of P. vivax cases in 1995, it decreasing in 1999, is the lack of border controls over workers coming to Turkey. The other internationally imported cases are from Syria, Sudan, Pakistan, Afghanistan, Nigeria, India, Azerbaijan, Malaysia, Ghana, Indonesia, Yemen. Our examinations have shown that none of these internationally imported cases

A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots.

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Bejon, Philip; Williams, Thomas N; Nyundo, Christopher; Hay, Simon I; Benz, David; Gething, Peter W; Otiende, Mark; Peshu, Judy; Bashraheil, Mahfudh; Greenhouse, Bryan; Bousema, Teun; Bauni, Evasius; Marsh, Kevin; Smith, David L; Borrmann, Steffen

2014-04-24

Malaria transmission is spatially heterogeneous. This reduces the efficacy of control strategies, but focusing control strategies on clusters or 'hotspots' of transmission may be highly effective. Among 1500 homesteads in coastal Kenya we calculated (a) the fraction of febrile children with positive malaria smears per homestead, and (b) the mean age of children with malaria per homestead. These two measures were inversely correlated, indicating that children in homesteads at higher transmission acquire immunity more rapidly. This inverse correlation increased gradually with increasing spatial scale of analysis, and hotspots of febrile malaria were identified at every scale. We found hotspots within hotspots, down to the level of an individual homestead. Febrile malaria hotspots were temporally unstable, but 4 km radius hotspots could be targeted for 1 month following 1 month periods of surveillance.DOI: http://dx.doi.org/10.7554/eLife.02130.001. Copyright © 2014, Bejon et al.

Antibody reactivities to glutamate-rich peptides of Plasmodium falciparum parasites in humans from areas of different malaria endemicity

DEFF Research Database (Denmark)

Jakobsen, P H; Theander, T G; Hviid, L

1996-01-01

Synthetic P. falciparum peptides were evaluated as tools in epidemiological investigations of malaria. Plasma IgM and IgG antibody reactivities against synthetic peptides covering sequences of glutamate-rich protein (GLURP) and acidic-basic repeat antigen (ABRA) were measured by ELISA...... in individuals from malaria-endemic areas of Sudan, Indonesia and The Gambia to study antibody responses to these peptides in donors living in areas of different malaria endemicity. IgG and IgM reactivities to the peptides increased with malaria endemicity, although there were no differences in reactivities...... tested were shortlived in most patients. In Gambian children with malaria, IgM reactivities but not IgG antibody reactivities against the ABRA peptide were higher in those with mild malaria than in those with severe malaria. The peptides may be useful in future epidemiological studies, especially...

Frequently Asked Questions (FAQs) about Malaria

Science.gov (United States)

... Facebook Tweet Share Compartir The Disease What is Malaria? Malaria is a serious and sometimes fatal disease ... cycle of disease and poverty. How People Get Malaria (Transmission) How is malaria transmitted? Usually, people get ...

Malaria, malnutrition, and birthweight

DEFF Research Database (Denmark)

Cates, Jordan E.; Unger, Holger W.; Briand, Valerie

2017-01-01

were identified by the Maternal Malaria and Malnutrition (M3) initiative using a convenience sampling approach and were eligible for pooling given adequate ethical approval and availability of essential variables. Study-specific adjusted effect estimates were calculated using inverse probability...... be multiplicative interaction between malaria infection at enrollment and low MUAC within studies conducted in Africa; however, this finding was not consistent on the additive scale, when accounting for multiple comparisons, or when using other definitions of malaria and malnutrition. The major limitations...... of the study included availability of only 2 cross-sectional measurements of malaria and the limited availability of ultrasound-based pregnancy dating to assess impacts on preterm birth and fetal growth in all studies.  Conclusions : Pregnant women with malnutrition and malaria infection are at increased risk...

Comparative evaluation of two rapid field tests for malaria diagnosis: Partec Rapid Malaria Test® and Binax Now® Malaria Rapid Diagnostic Test.

Science.gov (United States)

Nkrumah, Bernard; Acquah, Samuel Ek; Ibrahim, Lukeman; May, Juergen; Brattig, Norbert; Tannich, Egbert; Nguah, Samuel Blay; Adu-Sarkodie, Yaw; Huenger, Frank

2011-05-23

About 90% of all malaria deaths in sub-Saharan Africa occur in children under five years. Fast and reliable diagnosis of malaria requires confirmation of the presence of malaria parasites in the blood of patients with fever or history suggestive of malaria; hence a prompt and accurate diagnosis of malaria is the key to effective disease management. Confirmation of malaria infection requires the availability of a rapid, sensitive, and specific testing at an affordable cost. We compared two recent methods (the novel Partec Rapid Malaria Test® (PT) and the Binax Now® Malaria Rapid Diagnostic Test (BN RDT) with the conventional Giemsa stain microscopy (GM) for the diagnosis of malaria among children in a clinical laboratory of a hospital in a rural endemic area of Ghana. Blood samples were collected from 263 children admitted with fever or a history of fever to the pediatric clinic of the Agogo Presbyterian Hospital. The three different test methods PT, BN RDT and GM were performed independently by well trained and competent laboratory staff to assess the presence of malaria parasites. Results were analyzed and compared using GM as the reference standard. In 107 (40.7%) of 263 study participants, Plasmodium sp. was detected by GM. PT and BN RDT showed positive results in 111 (42.2%) and 114 (43.4%), respectively. Compared to GM reference standard, the sensitivities of the PT and BN RDT were 100% (95% CI: 96.6-100) and 97.2% (95% CI: 92.0-99.4), respectively, specificities were 97.4% (95% CI: 93.6-99.3) and 93.6% (95% CI: 88.5-96.9), respectively. There was a strong agreement (kappa) between the applied test methods (GM vs PT: 0.97; p < 0.001 and GM vs BN RDT: 0.90; p < 0.001). The average turnaround time per tests was 17 minutes. In this study two rapid malaria tests, PT and BN RDT, demonstrated a good quality of their performance compared to conventional GM. Both methods require little training, have short turnaround times, are applicable as well as affordable and

Long-Lasting Insecticidal Hammocks for controlling forest malaria: a community-based trial in a rural area of central Vietnam.

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Ngo Duc Thang

2009-10-01

Full Text Available In Vietnam, malaria remains a problem in some remote areas located along its international borders and in the central highlands, partly due to the bionomics of the local vector, mainly found in forested areas and less vulnerable to standard control measures. Long Lasting Insecticidal Hammocks (LLIH, a tailored and user-friendly tool for forest workers, may further contribute in reducing the malaria burden. Their effectiveness was tested in a large community-based intervention trial carried out in Ninh Thuan province in Central Vietnam.Thirty villages (population 18,646 were assembled in 20 clusters (1,000 individuals per cluster that were randomly allocated to either the intervention or control group (no LLIH after stratification according to the pre-intervention P. falciparum antibody prevalence ( or =30%. LLIH were distributed to the intervention group in December 2004. For the following 2 years, the incidence of clinical malaria and the prevalence of infection were determined by passive case detection at community level and by bi-annual malariometric surveys. A 2-fold larger effect on malaria incidence in the intervention as compared to the control group was observed. Similarly, malaria prevalence decreased more substantially in the intervention (1.6-fold greater reduction than in the control group. Both for incidence and prevalence, a stronger and earlier effect of the intervention was observed in the high endemicity stratum. The number of malaria cases and infections averted by the intervention overall was estimated at 10.5 per 1,000 persons and 5.6/100 individuals, respectively, for the last half of 2006. In the high endemicity stratum, the impact was much higher, i.e. 29/1000 malaria cases and 15.7 infections/100 individuals averted.LLIH reduced malaria incidence and prevalence in this remote and forested area of Central Vietnam. As the targets of the newly-launched Global Malaria Action Plan include the 75% reduction of the global

Rapid assessment of malaria transmission using age-specific sero-conversion rates.

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Laveta Stewart

2009-06-01

Full Text Available Malaria transmission intensity is a crucial determinant of malarial disease burden and its measurement can help to define health priorities. Rapid, local estimates of transmission are required to focus resources better but current entomological and parasitological methods for estimating transmission intensity are limited in this respect. An alternative is determination of antimalarial antibody age-specific sero-prevalence to estimate sero-conversion rates (SCR, which have been shown to correlate with transmission intensity. This study evaluated SCR generated from samples collected from health facility attendees as a tool for a rapid assessment of malaria transmission intensity.The study was conducted in north east Tanzania. Antibodies to Plasmodium falciparum merozoite antigens MSP-1(19 and AMA-1 were measured by indirect ELISA. Age-specific antibody prevalence was analysed using a catalytic conversion model based on maximum likelihood to generate SCR. A pilot study, conducted near Moshi, found SCRs for AMA-1 were highly comparable between samples collected from individuals in a conventional cross-sectional survey and those collected from attendees at a local health facility. For the main study, 3885 individuals attending village health facilities in Korogwe and Same districts were recruited. Both malaria parasite prevalence and sero-positivity were higher in Korogwe than in Same. MSP-1(19 and AMA-1 SCR rates for Korogwe villages ranged from 0.03 to 0.06 and 0.07 to 0.21 respectively. In Same district there was evidence of a recent reduction in transmission, with SCR among those born since 1998 [MSP-1(19 0.002 to 0.008 and AMA-1 0.005 to 0.014 ] being 5 to 10 fold lower than among individuals born prior to 1998 [MSP-1(19 0.02 to 0.04 and AMA-1 0.04 to 0.13]. Current health facility specific estimates of SCR showed good correlations with malaria incidence rates in infants in a contemporaneous clinical trial (MSP-1(19 r(2 = 0.78, p<0.01 & AMA-1 r

Muscling out malaria

DEFF Research Database (Denmark)

Hughes, David Peter; Boomsma, Jacobus Jan

2006-01-01

) [2] highlighted the back-to-back articles in Science 3 and 4 that demonstrated the potential biocontrol of malaria by targeting mosquitoes with entomopathogenic fungi (Metarhizium and Beauveria spp.). The wide impact of the original articles and the need to find alternatives to pesticidal control...... where malaria is endemic, humanity cannot afford shortcuts, because any failures owing to poor management or premature implementation will reduce local governmental support rather than enhance it (Andrew Read, pers. commun.). Therefore, if we are to ‘muscle out malaria', well...... of key importance, and the new focus on fungal biocontrol of malaria should therefore act as a catalyst for further research on the basic biology of fungal pathogens. Understanding morphological, biochemical or immune system-based resistance to insect pathogenic fungi will be easier if we know...

Malaria Surveillance - United States, 2015.

Science.gov (United States)

Mace, Kimberly E; Arguin, Paul M; Tan, Kathrine R

2018-05-04

Malaria in humans is caused by intraerythrocytic protozoa of the genus Plasmodium. These parasites are transmitted by the bite of an infective female Anopheles species mosquito. The majority of malaria infections in the United States occur among persons who have traveled to regions with ongoing malaria transmission. However, malaria is occasionally acquired by persons who have not traveled out of the country through exposure to infected blood products, congenital transmission, laboratory exposure, or local mosquitoborne transmission. Malaria surveillance in the United States is conducted to provide information on its occurrence (e.g., temporal, geographic, and demographic), guide prevention and treatment recommendations for travelers and patients, and facilitate transmission control measures if locally acquired cases are identified. This report summarizes confirmed malaria cases in persons with onset of illness in 2015 and summarizes trends in previous years. Malaria cases diagnosed by blood film microscopy, polymerase chain reaction, or rapid diagnostic tests are reported to local and state health departments by health care providers or laboratory staff members. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS), the National Notifiable Diseases Surveillance System (NNDSS), or direct CDC consultations. CDC reference laboratories provide diagnostic assistance and conduct antimalarial drug resistance marker testing on blood samples submitted by health care providers or local or state health departments. This report summarizes data from the integration of all NMSS and NNDSS cases, CDC reference laboratory reports, and CDC clinical consultations. CDC received reports of 1,517 confirmed malaria cases, including one congenital case, with an onset of symptoms in 2015 among persons who received their diagnoses in the United States. Although the number of

The effect of daily co-trimoxazole prophylaxis on natural development of antibody-mediated immunity against P. falciparum malaria infection in HIV-exposed uninfected Malawian children.

Directory of Open Access Journals (Sweden)

Herbert Longwe

Full Text Available Co-trimoxazole prophylaxis, currently recommended in HIV-exposed, uninfected (HEU children as protection against opportunistic infections, also has some anti-malarial efficacy. We determined whether daily co-trimoxazole prophylaxis affects the natural development of antibody-mediated immunity to blood-stage Plasmodium falciparum malaria infection.Using an enzyme-linked immunosorbent assay, we measured antibodies to 8 Plasmodium falciparum antigens (AMA-1, MSP-119, MSP-3, PfSE, EBA-175RII, GLURP R0, GLURP R2 and CSP in serum samples from 33 HEU children and 31 HIV-unexposed, uninfected (HUU children, collected at 6, 12 and 18 months of age.Compared to HIV-uninfected children, HEU children had significantly lower levels of specific IgG against AMA-1 at 6 months (p = 0.001, MSP-119 at 12 months (p = 0.041 and PfSE at 6 months (p = 0.038, 12 months (p = 0.0012 and 18 months (p = 0.0097. No differences in the IgG antibody responses against the rest of the antigens were observed between the two groups at all time points. The breadth of specificity of IgG response was reduced in HEU children compared to HUU children during the follow up period.Co-trimoxazole prophylaxis seems to reduce IgG antibody responses to P. falciparum blood stage antigens, which could be as a result of a reduction in exposure of those children under this regime. Although antibody responses were regarded as markers of exposure in this study, further studies are required to establish whether these responses are correlated in any way to clinical immunity to malaria.

Preventing childhood malaria in Africa by protecting adults from mosquitoes with insecticide-treated nets.

Directory of Open Access Journals (Sweden)

Gerry F Killeen

2007-07-01

Full Text Available Malaria prevention in Africa merits particular attention as the world strives toward a better life for the poorest. Insecticide-treated nets (ITNs represent a practical means to prevent malaria in Africa, so scaling up coverage to at least 80% of young children and pregnant women by 2010 is integral to the Millennium Development Goals (MDG. Targeting individual protection to vulnerable groups is an accepted priority, but community-level impacts of broader population coverage are largely ignored even though they may be just as important. We therefore estimated coverage thresholds for entire populations at which individual- and community-level protection are equivalent, representing rational targets for ITN coverage beyond vulnerable groups.Using field-parameterized malaria transmission models, we show that high (80% use but exclusively targeted coverage of young children and pregnant women (representing <20% of the population will deliver limited protection and equity for these vulnerable groups. In contrast, relatively modest coverage (35%-65% use, with this threshold depending on ecological scenario and net quality of all adults and children, rather than just vulnerable groups, can achieve equitable community-wide benefits equivalent to or greater than personal protection.Coverage of entire populations will be required to accomplish large reductions of the malaria burden in Africa. While coverage of vulnerable groups should still be prioritized, the equitable and communal benefits of wide-scale ITN use by older children and adults should be explicitly promoted and evaluated by national malaria control programmes. ITN use by the majority of entire populations could protect all children in such communities, even those not actually covered by achieving existing personal protection targets of the MDG, Roll Back Malaria Partnership, or the US President's Malaria Initiative.

Manual blood exchange transfusion does not significantly contribute to parasite clearance in artesunate-treated individuals with imported severe Plasmodium falciparum malaria

NARCIS (Netherlands)

Kreeftmeijer-Vegter, Annemarie R.; Melo, Mariana de Mendonça; de Vries, Peter J.; Koelewijn, Rob; van Hellemond, Jaap J.; van Genderen, Perry J. J.

2013-01-01

Exchange transfusion (ET) has remained a controversial adjunct therapy for the treatment of severe malaria. In order to assess the relative contribution of ET to parasite clearance in severe malaria, all patients receiving ET as an adjunct treatment to parenteral quinine or to artesunate were

Manual blood exchange transfusion does not significantly contribute to parasite clearance in artesunate-treated individuals with imported severe Plasmodium falciparum malaria

NARCIS (Netherlands)

A.R. Kreeftmeijer-Vegter (Annemarie); M.M. de Melo (Mariana ); P.J. de Vries (Peter); R. Koelewijn (Rob); J.J. van Hellemond (Jaap); P.J.J. van Genderen (Perry)

2013-01-01

textabstractBackground: Exchange transfusion (ET) has remained a controversial adjunct therapy for the treatment of severe malaria. In order to assess the relative contribution of ET to parasite clearance in severe malaria, all patients receiving ET as an adjunct treatment to parenteral quinine or

Malaria and Travelers

Science.gov (United States)

... Providers, Emergency Consultations, and General Public. Contact Us Malaria and Travelers for U.S. Residents Recommend on Facebook ... may be at risk for infection. Determine if malaria transmission occurs at the destinations Obtain a detailed ...

Malaria and related outcomes in patients with intestinal helminths: a cross-sectional study.

Science.gov (United States)

Degarege, Abraham; Legesse, Mengistu; Medhin, Girmay; Animut, Abebe; Erko, Berhanu

2012-11-09

The effects of helminth co-infection on malaria in humans remain uncertain. This study aimed to evaluate the nature of association of intestinal helminths with prevalence and clinical outcomes of Plasmodium infection. A cross-sectional study involving 1,065 malaria suspected febrile patients was conducted at Dore Bafeno Health Center, Southern Ethiopia, from December 2010 to February 2011. Plasmodium and intestinal helminth infections were diagnosed using Giemsa-stained blood films and Kato-Katz technique, respectively. Haemoglobin level was determined using a haemocue machine. Among 1,065 malaria suspected febrile patients, 28.8% were positive for Plasmodium parasites (P. falciparum =13.0%, P. vivax =14.5%, P. falciparum and P. vivax =1.3%). Among 702 patients who provided stool samples, 53.8%, 31.6% and 19.4% were infected with intestinal helminths, Plasmodium alone and with both Plasmodium and intestinal helminths, respectively. The prevalence of infections with Ascaris lumbricoides (A. lumbricoides), Trichuris trichiura (T. trichiura), Schistosoma mansoni (S. mansoni) and hookworm (9.8%) were 35.9%, 15.8%, 11.7% and 9.8%, respectively. Out of the 222 (31.6%) Plasmodium infected cases, 9 (4.1%) had severe malaria. P. falciparum infection was more common in febrile patients infected with A. lumbricoides alone (21.3%), T. trichiura alone (23.1%) and S. mansoni alone (23.1%) compared to those without intestinal helminth infections (9.3%) (phelminths than in those who were not infected with intestinal helminths (adjusted OR=1.58, 95% CI=1.13-2.22). The chance of developing non-severe P. falciparum malaria were 2.6, 2.8 and 3.3 times higher in individuals infected with A. lumbricoides alone, T. trichiura alone and S. mansoni alone, respectively, compared to intestinal helminth-free individuals (phelminth species (phelminth infected individuals was significantly increased with the number of intestinal helminths species (p=0.027). Individuals who were co-infected with

Malaria and related outcomes in patients with intestinal helminths: a cross-sectional study

Directory of Open Access Journals (Sweden)

Degarege Abraham

2012-11-01

Full Text Available Abstract Background The effects of helminth co-infection on malaria in humans remain uncertain. This study aimed to evaluate the nature of association of intestinal helminths with prevalence and clinical outcomes of Plasmodium infection. Methods A cross-sectional study involving 1,065 malaria suspected febrile patients was conducted at Dore Bafeno Health Center, Southern Ethiopia, from December 2010 to February 2011. Plasmodium and intestinal helminth infections were diagnosed using Giemsa-stained blood films and Kato-Katz technique, respectively. Haemoglobin level was determined using a haemocue machine. Results Among 1,065 malaria suspected febrile patients, 28.8% were positive for Plasmodium parasites (P. falciparum =13.0%, P. vivax =14.5%, P. falciparum and P. vivax =1.3%. Among 702 patients who provided stool samples, 53.8%, 31.6% and 19.4% were infected with intestinal helminths, Plasmodium alone and with both Plasmodium and intestinal helminths, respectively. The prevalence of infections with Ascaris lumbricoides (A. lumbricoides, Trichuris trichiura (T. trichiura, Schistosoma mansoni (S. mansoni and hookworm (9.8% were 35.9%, 15.8%, 11.7% and 9.8%, respectively. Out of the 222 (31.6% Plasmodium infected cases, 9 (4.1% had severe malaria. P. falciparum infection was more common in febrile patients infected with A. lumbricoides alone (21.3%, T. trichiura alone (23.1% and S. mansoni alone (23.1% compared to those without intestinal helminth infections (9.3% (pP. falciparum malaria were 2.6, 2.8 and 3.3 times higher in individuals infected with A. lumbricoides alone, T. trichiura alone and S. mansoni alone, respectively, compared to intestinal helminth-free individuals (pP. falciparum increased with the number of intestinal helminth species (pPlasmodium density among intestinal helminth infected individuals was significantly increased with the number of intestinal helminths species (p=0.027. Individuals who were co-infected with different

Malaria and Tropical Travel

Centers for Disease Control (CDC) Podcasts

2008-05-15

Malaria is a serious mosquito-borne disease that can lead to death. This podcast discusses malaria risk when traveling to tropical areas, as well as how to protect yourself and your family from malaria infection.  Created: 5/15/2008 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 5/29/2008.

Malaria successes and challenges in Asia.

Science.gov (United States)

Bhatia, Rajesh; Rastogi, Rakesh Mani; Ortega, Leonard

2013-12-01

Asia ranks second to Africa in terms of malaria burden. In 19 countries of Asia, malaria is endemic and 2.31 billion people or 62% of the total population in these countries are at risk of malaria. In 2010, WHO estimated around 34.8 million cases and 45,600 deaths due to malaria in Asia. In 2011, 2.7 million cases and > 2000 deaths were reported. India, Indonesia, Myanmar and Pakistan are responsible for >85% of the reported cases (confirmed) and deaths in Asia. In last 10 yr, due to availability of donor's fund specially from Global fund, significant progress has been made by the countries in Asia in scaling-up malaria control interventions which were instrumental in reducing malaria morbidity and mortality significantly. There is a large heterogeneity in malaria epidemiology in Asia. As a result, the success in malaria control/elimination is also diverse. As compared to the data of the year 2000, out of 19 malaria endemic countries, 12 countries were able to reduce malaria incidence (microscopically confirmed cases only) by 75%. Two countries, namely Bangladesh and Malaysia are projected to reach 75% reduction by 2015 while India is projected to reach 50-75% only by 2015. The trend could not be assessed in four countries, namely Indonesia, Myanmar, Pakistan and Timor-Leste due to insufficient consistent data. Numerous key challenges need to be addressed to sustain the gains and eliminate malaria in most parts of Asia. Some of these are to control the spread of resistance in Plasmodium falciparum to artemisinin, control of outdoor transmission, control of vivax malaria and ensuring universal coverage of key interventions. Asia has the potential to influence the malaria epidemiology all over the world as well as to support the global efforts in controlling and eliminating malaria through production of quality-assured ACTs, RDTs and long-lasting insecticidal nets.

Evidence from a natural experiment that malaria parasitemia is pathogenic in retinopathy-negative cerebral malaria.

Science.gov (United States)

Small, Dylan S; Taylor, Terrie E; Postels, Douglas G; Beare, Nicholas Av; Cheng, Jing; MacCormick, Ian Jc; Seydel, Karl B

2017-06-07

Cerebral malaria (CM) can be classified as retinopathy-positive or retinopathy-negative, based on the presence or absence of characteristic retinal features. While malaria parasites are considered central to the pathogenesis of retinopathy-positive CM, their contribution to retinopathy-negative CM is largely unknown. One theory is that malaria parasites are innocent bystanders in retinopathy-negative CM and the etiology of the coma is entirely non-malarial. Because hospitals in malaria-endemic areas often lack diagnostic facilities to identify non-malarial causes of coma, it has not been possible to evaluate the contribution of malaria infection to retinopathy-negative CM. To overcome this barrier, we studied a natural experiment involving genetically inherited traits, and find evidence that malaria parasitemia does contribute to the pathogenesis of retinopathy-negative CM. A lower bound for the fraction of retinopathy-negative CM that would be prevented if malaria parasitemia were to be eliminated is estimated to be 0.93 (95% confidence interval: 0.68, 1).

Modelling malaria treatment practices in Bangladesh using spatial statistics

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Haque Ubydul

2012-03-01

Full Text Available Abstract Background Malaria treatment-seeking practices vary worldwide and Bangladesh is no exception. Individuals from 88 villages in Rajasthali were asked about their treatment-seeking practices. A portion of these households preferred malaria treatment from the National Control Programme, but still a large number of households continued to use drug vendors and approximately one fourth of the individuals surveyed relied exclusively on non-control programme treatments. The risks of low-control programme usage include incomplete malaria treatment, possible misuse of anti-malarial drugs, and an increased potential for drug resistance. Methods The spatial patterns of treatment-seeking practices were first examined using hot-spot analysis (Local Getis-Ord Gi statistic and then modelled using regression. Ordinary least squares (OLS regression identified key factors explaining more than 80% of the variation in control programme and vendor treatment preferences. Geographically weighted regression (GWR was then used to assess where each factor was a strong predictor of treatment-seeking preferences. Results Several factors including tribal affiliation, housing materials, household densities, education levels, and proximity to the regional urban centre, were found to be effective predictors of malaria treatment-seeking preferences. The predictive strength of each of these factors, however, varied across the study area. While education, for example, was a strong predictor in some villages, it was less important for predicting treatment-seeking outcomes in other villages. Conclusion Understanding where each factor is a strong predictor of treatment-seeking outcomes may help in planning targeted interventions aimed at increasing control programme usage. Suggested strategies include providing additional training for the Building Resources across Communities (BRAC health workers, implementing educational programmes, and addressing economic factors.

Malaria infection has spatial, temporal, and spatiotemporal heterogeneity in unstable malaria transmission areas in northwest Ethiopia.

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Kassahun Alemu

Full Text Available BACKGROUND: Malaria elimination requires successful nationwide control efforts. Detecting the spatiotemporal distribution and mapping high-risk areas are useful to effectively target pockets of malaria endemic regions for interventions. OBJECTIVE: The aim of the study was to identify patterns of malaria distribution by space and time in unstable malaria transmission areas in northwest Ethiopia. METHODS: Data were retrieved from the monthly reports stored in the district malaria offices for the period between 2003 and 2012. Eighteen districts in the highland and fringe malaria areas were included and geo-coded for the purpose of this study. The spatial data were created in ArcGIS10 for each district. The Poisson model was used by applying Kulldorff methods using the SaTScan™ software to analyze the purely temporal, spatial and space-time clusters of malaria at a district levels. RESULTS: The study revealed that malaria case distribution has spatial, temporal, and spatiotemporal heterogeneity in unstable transmission areas. Most likely spatial malaria clusters were detected at Dera, Fogera, Farta, Libokemkem and Misrak Este districts (LLR =197764.1, p<0.001. Significant spatiotemporal malaria clusters were detected at Dera, Fogera, Farta, Libokemkem and Misrak Este districts (LLR=197764.1, p<0.001 between 2003/1/1 and 2012/12/31. A temporal scan statistics identified two high risk periods from 2009/1/1 to 2010/12/31 (LLR=72490.5, p<0.001 and from 2003/1/1 to 2005/12/31 (LLR=26988.7, p<0.001. CONCLUSION: In unstable malaria transmission areas, detecting and considering the spatiotemporal heterogeneity would be useful to strengthen malaria control efforts and ultimately achieve elimination.

Malaria, desnutrición y parasitosis intestinal en los niños colombianos: interrelaciones interrrelations between malaria, malnutrition and intestinal parasitism in colombian children

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Jaime Carmona Fonseca

2004-09-01

Full Text Available Este trabajo resume datos colombianos y los hallazgos del Grupo Malaria (Universidad de Antioquia sobre las relaciones entre malaria, desnutrición y funcionamiento inmunitario, trabajos realizados en niños (4-11 años de las poblaciones antioqueñas de Turbo, El Bagre y Zaragoza. Se hace énfasis en las relaciones malaria, parásitos intestinales y desnutrición (desnutrición crónica, hipovitaminosis A, las cuales se exploran a través de su articulación en el sistema inmunitario. Se formulan recomendaciones para la aplicación clínica (individual y epidemiológica (colectiva con respecto a la formulación de suplemento de vitamina A y antihelmínticos de amplio espectro. En Turbo y en El Bagre y Zaragoza: 1 la frecuencia de malaria registra índices parasitarios anuales de 39 (Turbo y 156 casos por cada mil sujetos expuestos (El Bagre-Zaragoza en 1996-2000; 2 el riesgo de desnutrición crónica (índice talla/ edad es de 63% en los niños de 3-11 años; 3 se encontró anemia en el 26% de los palúdicos y 17% de los no palúdicos; 4 el 65% de los niños con malaria y el 35% de aquellos sin malaria mostraron valores de retinol bajos (<0,3 µg/mL; 5 se hallaron niveles anormalmente bajos de apoproteína A-1, tanto en los niños sin malaria como, sobre todo, en los que sí la tenían; 6 el 96% de los niños (4-9 años con malaria mostraron títulos de interleuquina 10 (IL10 muy altos con relación a lo normal y estadísticamente superiores a los exhibidos por los niños sin malaria; 7 los títulos de IgE total y específica anti-Plasmodium estuvieron anormalmente altos en los niños de ambos municipios e igual sucedió con los niveles de FNT-; 8 en estudiantes y docentes de enfermería, aparentemente sanos, con edades de 18-44 años, hallamos parásitos intestinales en el 97% y parásitos intestinales patógenos en el 42%. En menores de 5 años de Turbo hay parásitos intestinales patógenos en un 30-35% de los niños, con predominio de G

The use of a GIS-based malaria information system for malaria research and control in South Africa.

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Martin, Carrin; Curtis, Bronwyn; Fraser, Colleen; Sharp, Brian

2002-12-01

The paper aims to outline the innovative development and application of a Geographical Information System based Malaria Information System for malaria research and control in South Africa. This system is a product of collaboration between the Malaria Control Programmes and the Malaria Research Programme of the Medical Research Council of South Africa. The ability of such a system to process data timeously into a usable format is discussed, as well as its relevance to malaria research, appropriate malaria control measures, tourism, and social and economic development.

Severe malaria in Europe

DEFF Research Database (Denmark)

Kurth, Florian; Develoux, Michel; Mechain, Matthieu

2017-01-01

BACKGROUND: Malaria remains one of the most serious infections for travellers to tropical countries. Due to the lack of harmonized guidelines a large variety of treatment regimens is used in Europe to treat severe malaria. METHODS: The European Network for Tropical Medicine and Travel Health (Trop......Net) conducted an 8-year, multicentre, observational study to analyse epidemiology, treatment practices and outcomes of severe malaria in its member sites across Europe. Physicians at participating TropNet centres were asked to report pseudonymized retrospective data from all patients treated at their centre...... for microscopically confirmed severe Plasmodium falciparum malaria according to the 2006 WHO criteria. RESULTS: From 2006 to 2014 a total of 185 patients with severe malaria treated in 12 European countries were included. Three patients died, resulting in a 28-day survival rate of 98.4%. The majority of infections...

Public health system readiness to treat malaria in Odisha State of India.

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Hussain, Mohammad A; Dandona, Lalit; Schellenberg, David

2013-10-02

Early diagnosis and prompt treatment is a cornerstone of malaria control. In India, artemisinin combination therapy (ACT) became the first-line treatment for falciparum malaria and rapid diagnostic test (RDTs) kits were recommended for use at the grass-root level in the new malaria treatment policy (2010). Odisha State contributes about one-fourth of the total Indian malaria burden and 40% of falciparum infection. The present study assessed the health system readiness to deploy RDTs and ACT for malaria control across the State. Data collection was carried out from February to July 2012. Five of Odisha's 30 districts were selected through stratified random sampling, with stratification based on the phased roll-out of ACT and RDT. Two administrative 'blocks' were selected randomly in each district and data collected through health facility, auxiliary nurse midwives (ANMs) and accredited social health activist (ASHAs) assessments. Key informant interviews were conducted with individuals involved in the implementation of the malaria control programme. Of the 220 ANMs interviewed, 51.4% had been trained in malaria case management, including the use of ACT and RDT. A high proportion of ANM (80%) and AHSA (77%) had the necessary level of knowledge to be able to use RDT for malaria diagnosis. The proportion of ASHAs trained on malaria case management was 88.9% (209/235). However, 71% of ANM and 55% of ASHAs usually referred falciparum-positive patients to the health facility for treatment, the major reason for referral being the non-availability of drugs at the ANM and ASHA level. The relatively high level of knowledge about how to diagnose and treat malaria at the grass-root level was undermined by the poor availability of RDTs, ACT and primaquine tablets. This was associated with an unnecessarily high referral rate and potential delays in the treatment of this potentially life-threatening infection. Improvements in the supply chain for RDTs and ACT could dramatically

The Malaria Transition on the Arabian Peninsula: Progress toward a Malaria-Free Region between 1960–2010

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Snow, Robert W.; Amratia, Punam; Zamani, Ghasem; Mundia, Clara W.; Noor, Abdisalan M.; Memish, Ziad A.; Al Zahrani, Mohammad H.; Al Jasari, Adel; Fikri, Mahmoud; Atta, Hoda

2014-01-01

The transmission of malaria across the Arabian Peninsula is governed by the diversity of dominant vectors and extreme aridity. It is likely that where malaria transmission was historically possible it was intense and led to a high disease burden. Here, we review the speed of elimination, approaches taken, define the shrinking map of risk since 1960 and discuss the threats posed to a malaria-free Arabian Peninsula using the archive material, case data and published works. From as early as the 1940s, attempts were made to eliminate malaria on the peninsula but were met with varying degrees of success through to the 1970s; however, these did result in a shrinking of the margins of malaria transmission across the peninsula. Epidemics in the 1990s galvanised national malaria control programmes to reinvigorate control efforts. Before the launch of the recent global ambition for malaria eradication, countries on the Arabian Peninsula launched a collaborative malaria-free initiative in 2005. This initiative led a further shrinking of the malaria risk map and today locally acquired clinical cases of malaria are reported only in Saudi Arabia and Yemen, with the latter contributing to over 98% of the clinical burden. PMID:23548086

Timing of in utero malaria exposure influences fetal CD4 T cell regulatory versus effector differentiation

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Mary Prahl

2016-10-01

Full Text Available Abstract Background In malaria-endemic areas, the first exposure to malaria antigens often occurs in utero when the fetal immune system is poised towards the development of tolerance. Children exposed to placental malaria have an increased risk of clinical malaria in the first few years of life compared to unexposed children. Recent work has suggested the potential of pregnancy-associated malaria to induce immune tolerance in children living in malaria-endemic areas. A study was completed to evaluate the effect of malaria exposure during pregnancy on fetal immune tolerance and effector responses. Methods Using cord blood samples from a cohort of mother-infant pairs followed from early in pregnancy until delivery, flow cytometry analysis was completed to assess the relationship between pregnancy-associated malaria and fetal cord blood CD4 and dendritic cell phenotypes. Results Cord blood FoxP3+ Treg counts were higher in infants born to mothers with Plasmodium parasitaemia early in pregnancy (12–20 weeks of gestation; p = 0.048, but there was no association between Treg counts and the presence of parasites in the placenta at the time of delivery (by loop-mediated isothermal amplification (LAMP; p = 0.810. In contrast, higher frequencies of activated CD4 T cells (CD25+FoxP3−CD127+ were observed in the cord blood of neonates with active placental Plasmodium infection at the time of delivery (p = 0.035. This population exhibited evidence of effector memory differentiation, suggesting priming of effector T cells in utero. Lastly, myeloid dendritic cells were higher in the cord blood of infants with histopathologic evidence of placental malaria (p < 0.0001. Conclusion Together, these data indicate that in utero exposure to malaria drives expansion of both regulatory and effector T cells in the fetus, and that the timing of this exposure has a pivotal role in determining the polarization of the fetal immune response.

History of malaria control in Tajikistan and rapid malaria appraisal in an agro-ecological setting.

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Matthys, Barbara; Sherkanov, Tohir; Karimov, Saifudin S; Khabirov, Zamonidin; Mostowlansky, Till; Utzinger, Jürg; Wyss, Kaspar

2008-10-26

Reported malaria cases in rice growing areas in western Tajikistan were at the root of a rapid appraisal of the local malaria situation in a selected agro-ecological setting where only scarce information was available. The rapid appraisal was complemented by a review of the epidemiology and control of malaria in Tajikistan and Central Asia from 1920 until today. Following a resurgence in the 1990s, malaria transmission has been reduced considerably in Tajikistan as a result of concerted efforts by the government and international agencies. The goal for 2015 is transmission interruption, with control interventions and surveillance currently concentrated in the South, where foci of Plasmodium vivax and Plasmodium falciparum persist. The rapid malaria appraisal was carried out in six communities of irrigated rice cultivation during the peak of malaria transmission (August/September 2007) in western Tajikistan. In a cross-sectional survey, blood samples were taken from 363 schoolchildren and examined for Plasmodium under a light microscope. A total of 56 farmers were interviewed about agricultural activities and malaria. Potential Anopheles breeding sites were characterized using standardized procedures. A literature review on the epidemiology and control of malaria in Tajikistan was conducted. One case of P. vivax was detected among the 363 schoolchildren examined (0.28%). The interviewees reported to protect themselves against mosquito bites and used their own concepts on fever conditions, which do not distinguish between malaria and other diseases. Three potential malaria vectors were identified, i.e. Anopheles superpictus, Anopheles pulcherrimus and Anopheles hyrcanus in 58 of the 73 breeding sites examined (79.5%). Rice paddies, natural creeks and man-made ponds were the most important Anopheles habitats. The presence of malaria vectors and parasite reservoirs, low awareness of, and protection against malaria in the face of population movements and inadequate

History of malaria control in Tajikistan and rapid malaria appraisal in an agro-ecological setting

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Utzinger Jürg

2008-10-01

Full Text Available Abstract Background Reported malaria cases in rice growing areas in western Tajikistan were at the root of a rapid appraisal of the local malaria situation in a selected agro-ecological setting where only scarce information was available. The rapid appraisal was complemented by a review of the epidemiology and control of malaria in Tajikistan and Central Asia from 1920 until today. Following a resurgence in the 1990s, malaria transmission has been reduced considerably in Tajikistan as a result of concerted efforts by the government and international agencies. The goal for 2015 is transmission interruption, with control interventions and surveillance currently concentrated in the South, where foci of Plasmodium vivax and Plasmodium falciparum persist. Methods The rapid malaria appraisal was carried out in six communities of irrigated rice cultivation during the peak of malaria transmission (August/September 2007 in western Tajikistan. In a cross-sectional survey, blood samples were taken from 363 schoolchildren and examined for Plasmodium under a light microscope. A total of 56 farmers were interviewed about agricultural activities and malaria. Potential Anopheles breeding sites were characterized using standardized procedures. A literature review on the epidemiology and control of malaria in Tajikistan was conducted. Results One case of P. vivax was detected among the 363 schoolchildren examined (0.28%. The interviewees reported to protect themselves against mosquito bites and used their own concepts on fever conditions, which do not distinguish between malaria and other diseases. Three potential malaria vectors were identified, i.e. Anopheles superpictus, Anopheles pulcherrimus and Anopheles hyrcanus in 58 of the 73 breeding sites examined (79.5%. Rice paddies, natural creeks and man-made ponds were the most important Anopheles habitats. Conclusion The presence of malaria vectors and parasite reservoirs, low awareness of, and protection against

The association of genetic markers and malaria infection in the Brazilian Western Amazonian region

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B Beiguelman

2003-06-01

Full Text Available Almost all individuals (182 belonging to an Amazonian riverine population (Portuchuelo, RO, Brazil were investigated for ascertaining data on epidemiological aspects of malaria. Thirteen genetic blood polymorphisms were investigated (ABO, MNSs, Rh, Kell, and Duffy systems, haptoglobins, hemoglobins, and the enzymes glucose-6-phosphate dehydrogenase, glyoxalase, phosphoglucomutase, carbonic anhydrase, red cell acid phosphatase, and esterase D. The results indicated that the Duffy system is associated with susceptibility to malaria, as observed in other endemic areas. Moreover, suggestions also arose indicating that the EsD and Rh loci may be significantly associated with resistance to malaria. If statistical type II errors and sample stratification could be ruled out, hypotheses on the existence of a causal mechanism or an unknown closely linked locus involved in susceptibility to malaria infection may explain the present findings.

Audiologic and otoacoustic emission evaluation in individuals exposed to noise and plaguecides

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Morini, Renata Graziele

2009-09-01

Full Text Available Introduction: The noise induced hearing loss (NIHL has been studied for many years and today the specialized literature also studies the synergic action of chemicals. Objective: To research the audiologic findings and DPOAE in workers exposed to occupational noise and plaguecides and to compare them with data obtained in individuals without exposure to these harmful elements. Method: 51 individuals were evaluated (102 ears, divided into three groups. Group I was composed by 17 workers with exposure to noise and plaguecides, all with neurosensorial auditory loss; group II was composed by 17 workers with exposure to noise and plaguecides with audiometric thresholds within normality standards (up to 25 dBNA and group III by 17 healthy individuals without auditory alterations and without exposure to noise and plaguecides, control group. Results: In the audiologic anamnesis, as for groups I and II, we observed that the main auditory complaints presented by the workers were those of recruitment (29.5%, tinnitus (26.5%, allergy (23.5% and arterial hypertension (12%. The findings of the audiometry appointed that the research's individuals did not present with auditory losses in the frequencies of 500 Hz, 1 and 2 kHz, the losses occurred in the frequencies of 3 and 8 kHz. As for the distortion-product otoacoustic emissions (DPOAEs, we observed that the individuals in group III had a major incidence of responses when compared to those of groups I and II. Conclusion: The results analysis allowed us to conclude that the DPOAE test represents an important tool for follow up and prevention of NIHL.

Stable malaria incidence despite scaling up control strategies in a malaria vaccine-testing site in Mali.

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Coulibaly, Drissa; Travassos, Mark A; Kone, Abdoulaye K; Tolo, Youssouf; Laurens, Matthew B; Traore, Karim; Diarra, Issa; Niangaly, Amadou; Daou, Modibo; Dembele, Ahmadou; Sissoko, Mody; Guindo, Bouréima; Douyon, Raymond; Guindo, Aldiouma; Kouriba, Bourema; Sissoko, Mahamadou S; Sagara, Issaka; Plowe, Christopher V; Doumbo, Ogobara K; Thera, Mahamadou A

2014-09-19

The recent decline in malaria incidence in many African countries has been attributed to the provision of prompt and effective anti-malarial treatment using artemisinin-based combination therapy (ACT) and to the widespread distribution of long-lasting, insecticide-treated bed nets (LLINs). At a malaria vaccine-testing site in Bandiagara, Mali, ACT was introduced in 2004, and LLINs have been distributed free of charge since 2007 to infants after they complete the Expanded Programme of Immunization (EPI) schedule and to pregnant women receiving antenatal care. These strategies may have an impact on malaria incidence. To document malaria incidence, a cohort of 400 children aged 0 to 14 years was followed for three to four years up to July 2013. Monthly cross-sectional surveys were done to measure the prevalence of malaria infection and anaemia. Clinical disease was measured both actively and passively through continuous availability of primary medical care. Measured outcomes included asymptomatic Plasmodium infection, anaemia and clinical malaria episodes. The incidence rate of clinical malaria varied significantly from June 2009 to July 2013 without a clear downward trend. A sharp seasonality in malaria illness incidence was observed with higher clinical malaria incidence rates during the rainy season. Parasite and anaemia point prevalence also showed seasonal variation with much higher prevalence rates during rainy seasons compared to dry seasons. Despite the scaling up of malaria prevention and treatment, including the widespread use of bed nets, better diagnosis and wider availability of ACT, malaria incidence did not decrease in Bandiagara during the study period.

Malaria epidemiology in an area of stable transmission in tribal population of Jharkhand, India.

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Das, Manoj K; Prajapati, Brijesh K; Tiendrebeogo, Régis W; Ranjan, Kumud; Adu, Bright; Srivastava, Amit; Khera, Harvinder K; Chauhan, Narendra; Tevatiya, Sanjay; Kana, Ikhlaq H; Sharma, Surya Kant; Singh, Subhash; Theisen, Michael

2017-05-02

Malaria remains an important health problem in India with approximately 1 million cases in 2014. Of these, 7% occurred in the Jharkhand state mainly in the tribal population. This study was conducted in Dumargarhi, a tribal village about 42 km east of Ranchi city, Jharkhand, from May 2014 to September 2016. Four point prevalence surveys were carried out during consecutive high (October-December) and low (June-August) transmission seasons. Malaria cases were recorded from April 2015 to April 2016 through fortnightly visits to the village. Adult mosquito densities were monitored fortnightly by manual catching using suction tube method. The study area consists of five hamlets inhabited by 945 individuals living in 164 households as recorded through a house-to-house census survey performed at enrollment. The study population consisted predominantly of the Munda (n = 425, 45%) and Oraon (n = 217, 23%) ethnic groups. Study participants were categorized as per their age 0-5, 6-10, 11-15 and >15 years. There were 99 cases of clinical malaria from April 2015 to April 2016 and all malaria cases confirmed by microscopy were attributed to Plasmodium falciparum (94 cases) and Plasmodium vivax (5 cases), respectively. During the high transmission season the mean density of P. falciparum parasitaemia per age group increased to a peak level of 23,601 parasites/μl in the 6-10 years age group and gradually declined in the adult population. Malaria attack rates, parasite prevalence and density levels in the study population showed a gradual decrease with increasing age. This finding is consistent with the phenomenon of naturally acquired immunity against malaria. Three vector species were detected: Anopheles fluviatilis, Anopheles annularis, and Anopheles culicifacies. The incoherence or complete out of phase pattern of the vector density peaks together with a high prevalence of parasite positive individuals in the study population explains the year-round malaria

Plasmodium vivax Malaria in Cambodia

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Siv, Sovannaroth; Roca-Feltrer, Arantxa; Vinjamuri, Seshu Babu; Bouth, Denis Mey; Lek, Dysoley; Rashid, Mohammad Abdur; By, Ngau Peng; Popovici, Jean; Huy, Rekol; Menard, Didier

2016-01-01

The Cambodian National Strategic Plan for Elimination of Malaria aims to move step by step toward elimination of malaria across Cambodia with an initial focus on Plasmodium falciparum malaria before achieving elimination of all forms of malaria, including Plasmodium vivax in 2025. The emergence of artemisinin-resistant P. falciparum in western Cambodia over the last decade has drawn global attention to support the ultimate goal of P. falciparum elimination, whereas the control of P. vivax lags much behind, making the 2025 target gradually less achievable unless greater attention is given to P. vivax elimination in the country. The following review presents in detail the past and current situation regarding P. vivax malaria, activities of the National Malaria Control Program, and interventional measures applied. Constraints and obstacles that can jeopardize our efforts to eliminate this parasite species are discussed. PMID:27708187

Laboratory diagnostics of malaria

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Siahaan, L.

2018-03-01

Even now, malaria treatment should only be administered after laboratory confirmation. There are several principal methods for diagnosing malaria. All these methods have their disadvantages.Presumptive treatment of malaria is widely practiced where laboratory tests are not readily available. Microscopy of Giemsa-stained thick and thin blood films remains the gold standard for the diagnosis of malaria infection. The technique of slide preparation, staining and reading are well known and standardized, and so is the estimate of the parasite density and parasite stages. Microscopy is not always available or feasible at primary health services in limited resource settings due to cost, lack of skilled manpower, accessories and reagents required. Rapid diagnostic tests (RDTs) are potential tools for parasite-based diagnosis since the tests are accurate in detecting malaria infections and are easy to use. The test is based on the capture of parasite antigen that released from parasitized red blood cells using monoclonal antibodies prepared against malaria antigen target. Polymerase Chain Reaction (PCR), depend on DNA amplification approaches and have higher sensitivity than microscopy. PCR it is not widely used due to the lack of a standardized methodology, high costs, and the need for highly-trained staff.

Malaria prophylaxis in the French armed forces: evolution of concepts.

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Touze, J E; Paule, P; Baudon, D; Boutin, J P

2001-01-01

Malaria is still a serious public health problem in the world and control remains a major priority for the approximately 25.000 French troops deployed, mostly on permanent assignment, in malaria transmission regions. Epidemiological surveillance of malaria provides data necessary to assess morbidity, monitor changing patterns of Plasmodium falciparum drug-sensitivity, and evaluate the efficacy of malaria control measures. About 540 cases were observed in 1999 for an incidence of 4.1 p. 100 men. year. Since 1991, strong emphasis has been placed on prophylaxis. In addition to vector control measures and individual protection against mosquito bites (impregnated bednets, protective clothing, application of repellents, and indoor insecticide spraying), drug prophylaxis has been recommended using a combination of 100 mg of chloroquine and 200 mg of proguanil chlorhydrate (CQ + PG) in a single capsule manufactured by the French Health Army Service. Initially this policy led to a significant decrease in malaria cases among French soldiers. However the incidence of malaria rose in 1995 and 1996. This recrudescence was attributed to poor compliance with chemoprophylaxis and to the declining efficacy of the CQ + PG combination. In response to these problems, a new policy was implemented especially in countries where cycloguanil-resistant Plasmodium falciparum incidence rate is increasing. The new chemoprophylactic regimen calls for a personal prescription of mefloquine. Doxycycline monohydrate is used in case of mefloquine contra-indication or intolerance. Combination of CQ + PG delivered in a single capsule remains a suitable chemoprophylactic regimen in Sahel countries as well as Horn of Africa.

Malaria early warning tool: linking inter-annual climate and malaria variability in northern Guadalcanal, Solomon Islands.

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Smith, Jason; Tahani, Lloyd; Bobogare, Albino; Bugoro, Hugo; Otto, Francis; Fafale, George; Hiriasa, David; Kazazic, Adna; Beard, Grant; Amjadali, Amanda; Jeanne, Isabelle

2017-11-21

Malaria control remains a significant challenge in the Solomon Islands. Despite progress made by local malaria control agencies over the past decade, case rates remain high in some areas of the country. Studies from around the world have confirmed important links between climate and malaria transmission. This study focuses on understanding the links between malaria and climate in Guadalcanal, Solomon Islands, with a view towards developing a climate-based monitoring and early warning for periods of enhanced malaria transmission. Climate records were sourced from the Solomon Islands meteorological service (SIMS) and historical malaria case records were sourced from the National Vector-Borne Disease Control Programme (NVBDCP). A declining trend in malaria cases over the last decade associated with improved malaria control was adjusted for. A stepwise regression was performed between climate variables and climate-associated malaria transmission (CMT) at different lag intervals to determine where significant relationships existed. The suitability of these results for use in a three-tiered categorical warning system was then assessed using a Mann-Whitney U test. Of the climate variables considered, only rainfall had a consistently significant relationship with malaria in North Guadalcanal. Optimal lag intervals were determined for prediction using R 2 skill scores. A highly significant negative correlation (R = - 0.86, R 2  = 0.74, p malaria transmission periods in January-June. Cross-validation emphasized the suitability of this relationship for forecasting purposes [Formula: see text]  as did Mann-Whitney U test results showing that rainfall below or above specific thresholds was significantly associated with above or below normal malaria transmission, respectively. This study demonstrated that rainfall provides the best predictor of malaria transmission in North Guadalcanal. This relationship is thought to be underpinned by the unique hydrological conditions

Prevalence of malaria and use of malaria risk reduction measures among resettled pregnant women in South Sudan

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Dræbel, Tania; Gueth Kueil, Bill; Meyrowitsch, Dan Wolf

2013-01-01

Background: The study assessed aspects of malaria infection, prevention and treatment in a population of resettled pregnant women in South Sudan. Methods: During April and May 2008, a cross-sectional study was carried out to estimate malaria prevalence and to assess the use of malaria risk...... ¼ 3.20, 95% CI 1.26–8.16; p ¼ 0.015). Conclusions: The results suggest that educational attainment need not be very advanced to affect practices of malaria prevention and treatment. Primary school attendance was a stronger predictor for use of malaria risk reduction measures than any of the other...... selected background characteristics. Educational attainment, information and communication about malaria prevention and control play a pivotal role in increasing and improving use of malaria risk reduction measures....

Influence Of Demographic Factors And History Of Malaria With The Incidence Malaria In MORU PHC

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Sudirman Manumpa

2017-01-01

Full Text Available Malaria morbidity in Moru health center, with parameter Annual Parasite Incident (API, amounted to 16.9% in 2014. This figure was still high when compared to the target of eliminating malaria in Indonesia about <1% in 2030. Incidence of malaria is more common in children aged 5 months - <12 years. This high rates of malaria leads to poverty, low level of learning achievement of children and in pregnant women causing low birth weight in babies and death. The purpose of this study was to analyze the factors that influence the incidence of tertian and Tropikana malaria or combined Tropikana and tertian (mix in Moru PHC in sub-district Alor Southwestern, Alor Regency.This study used a cross-sectional design, the population of study were all patients undergoing peripheral blood examination in Moru PHC’s laboratory from June to October 2015. The number of samples in this study was 173 respondents. The sampling technique was Simple Random Sampling. Instruments of data collection were a questionnaire and observation sheet.Results of the study by Chi-Square test showed that the factors influencing the incidence of malaria were socioeconomic status (sig 0,000, education level (sig 0.001. By using multivariate analysis with logistic regression test, results were obtained the age of 5 months - <12 value (sig 0.025 and socioeconomic status (sig 0,000 influencing the incidence of malaria.Variables that affect the incidence of malaria were demographic factors such as age, education level, socioeconomic status. It is advisable to harness swamp thus improving the economic status of society and build permanent house. Keywords: incidence malaria, demographic factors, history of malaria

[Imported malaria and HIV infection in Madrid. Clinical and epidemiological features].

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Ramírez-Olivencia, G; Herrero, M D; Subirats, M; de Juanes, J R; Peña, J M; Puente, S

2012-01-01

Few data are available in Spain data on human immunodeficiency virus (HIV) patients coinfected with malaria. This study has aimed to determine the epidemiological and clinical characteristics of imported malaria in patients coinfected with HIV. A case-series retrospective study was performed using the patient's medical records. The study population consisted on patients diagnosed with malaria attended in our center from january 1, 2002 to december 31, 2007. A total of 484 episodes of malaria, 398 of which were included in this study, were identified. Co-infection with HIV was described in 32 cases. All of them occurred in individuals presumably with some degree of semi-immunity. In the coinfected group, there were 13 cases (40.6%) asymptomatic, whereas this event occurred in 99 cases of patients not coinfected (37.2%) (P=0.707). The greater presence of anemia in co-infected patients (62.5% vs 32.3% in non-coinfected [P=0.001]) stands out. In present study, the clinical presentation forms were similar, regardless of the presence or absence of HIV infection. Although the study population does not reflect all possible scenarios of malaria and HIV coinfection, our results indicate the reality of patients attended in the Autonomous Community of Madrid. Copyright © 2011 Elsevier España, S.L. All rights reserved.

The role of age, ethnicity and environmental factors in modulating malaria risk in Rajasthali, Bangladesh

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Haque Ubydul

2011-12-01

Full Text Available Abstract Background Malaria is endemic in the Rajasthali region of the Chittagong Hill Tracts in Bangladesh and the Rajasthali region is the most endemic area of Bangladesh. Quantifying the role of environmental and socio-economic factors in the local spatial patterns of malaria endemicity can contribute to successful malaria control and elimination. This study aimed to investigate the role of environmental factors on malaria risk in Rajasthali and to quantify the geographical clustering in malaria risk unaccounted by these factors. Method A total of 4,200 (78.9%; N = 5,322 households were targeted in Rajasthali in July, 2009, and 1,400 individuals were screened using a rapid diagnostic test (Falci-vax. These data were linked to environmental and socio-economic data in a geographical information system. To describe the association between environmental factors and malaria risk, a generalized linear mixed model approach was utilized. The study investigated the role of environmental factors on malaria risk by calculating their population-attributable fractions (PAF, and used residual semivariograms to quantify the geographical clustering in malaria risk unaccounted by these factors. Results Overall malaria prevalence was 11.7%. Out of 5,322 households, 44.12% households were living in areas with malaria prevalence of ≥ 10%. The results from statistical analysis showed that age, ethnicity, proximity to forest, household density, and elevation were significantly and positively correlated with the malaria risk and PAF estimation. The highest PAF of malaria prevalence was 47.7% for third tertile (n = 467 of forest cover, 17.6% for second tertile (n = 467 of forest cover and 19.9% for household density >1,000. Conclusion Targeting of malaria health interventions at small spatial scales in Bangladesh should consider the social and socio-economic risk factors identified as well as alternative methods for improving equity of access to interventions

Simulation of the Impact of Climate Variability on Malaria Transmission in the Sahel

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Bomblies, A.; Eltahir, E.; Duchemin, J.

2007-12-01

A coupled hydrology and entomology model for simulation of malaria transmission and malaria transmitting mosquito population dynamics is presented. Model development and validation is done using field data and observations collected at Banizoumbou and Zindarou, Niger spanning three wet seasons, from 2005 through 2007. The primary model objective is the accurate determination of climate variability effects on village scale malaria transmission. Malaria transmission dependence on climate variables is highly nonlinear and complex. Temperature and humidity affect mosquito longevity, temperature controls parasite development rates in the mosquito as well as subadult mosquito development rates, and precipitation determines the formation and persistence of adequate breeding pools. Moreover, unsaturated zone hydrology influences overland flow, and climate controlled evapotranspiration rates and root zone uptake therefore also influence breeding pool formation. High resolution distributed hydrologic simulation allows representation of the small-scale ephemeral pools that constitute the primary habitat of Anopheles gambiae mosquitoes, the dominant malaria vectors in the Niger Sahel. Remotely sensed soil type, vegetation type, and microtopography rasters are used to assign the distributed parameter fields for simulation of the land surface hydrologic response to precipitation and runoff generation. Predicted runoff from each cell flows overland and into topographic depressions, with explicit representation of infiltration and evapotranspiration. The model's entomology component interacts with simulated pools. Subadult (aquatic stage) mosquito breeding is simulated in the pools, and water temperature dependent stage advancement rates regulate adult mosquito emergence into the model domain. Once emerged, adult mosquitoes are tracked as independent individual agents that interact with their immediate environment. Attributes relevant to malaria transmission such as gonotrophic

Maps of the Sri Lanka malaria situation preceding the tsunami and key aspects to be considered in the emergency phase and beyond

DEFF Research Database (Denmark)

Briët, Olivier J T; Galappaththy, Gawrie N L; Konradsen, Flemming

2005-01-01

is necessary, especially as December-February is normally the peak transmission season. Despite some losses, the Sri Lanka public health system is capable of dealing with the possible threat of a malaria outbreak after the tsunami. The influx of foreign medical assistance, drugs, and insecticides may interfere......BACKGROUND: Following the tsunami, a detailed overview of the area specific transmission levels is essential in assessing the risk of malaria in Sri Lanka. Recent information on vector insecticide resistance, parasite drug resistance, and insights into the national policy for malaria diagnosis...... of published reports and routinely collected information was performed. RESULTS: The incidence of malaria was only 1 case per thousand population in the 10 months leading up to the disaster, in the districts with the highest transmission. CONCLUSION: Although relocated people may be more exposed to mosquito...

Incidence of Severe Malaria Syndromes and Status of Immune Responses among Khat Chewer Malaria Patients in Ethiopia.

Directory of Open Access Journals (Sweden)

Tsige Ketema

Full Text Available Although more emphasis has been given to the genetic and environmental factors that determine host vulnerability to malaria, other factors that might have a crucial role in burdening the disease have not been evaluated yet. Therefore, this study was designed to assess the effect of khat chewing on the incidence of severe malaria syndromes and immune responses during malaria infection in an area where the two problems co-exist. Clinical, physical, demographic, hematological, biochemical and immunological data were collected from Plasmodium falciparum mono-infected malaria patients (age ≥ 10 years seeking medication in Halaba Kulito and Jimma Health Centers. In addition, incidences of severe malaria symptoms were assessed. The data were analyzed using SPSS (version 20 software. Prevalence of current khat chewer malaria patients was 57.38% (95%CI =53-61.56%. Malaria symptoms such as hyperpyrexia, prostration and hyperparasitemia were significantly lower (P0.05, IgG3 antibody was significantly higher (P<0.001 among khat chewer malaria patients. Moreover, IgM, IgG, IgG1and IgG3 antibodies had significant negative association (P<0.001 with parasite burden and clinical manifestations of severe malaria symptoms, but not with severe anemia and hypoglycemia. Additionally, a significant increment (P<0.05 in CD4+ T-lymphocyte population was observed among khat users. Khat might be an important risk factor for incidence of some severe malaria complications. Nevertheless, it can enhance induction of humoral immune response and CD4+ T-lymphocyte population during malaria infection. This calls for further investigation on the effect of khat on parasite or antigen-specifc protective malaria immunity and analysis of cytokines released upon malaria infection among khat chewers.

Anaemia and malaria in Yanomami communities with differing access to healthcare.

Science.gov (United States)

Grenfell, P; Fanello, C I; Magris, M; Goncalves, J; Metzger, W G; Vivas-Martínez, S; Curtis, C; Vivas, L

2008-07-01

Inequitable access to healthcare has a profound impact on the health of marginalised groups that typically suffer an excess burden of infectious disease morbidity and mortality. The Yanomami are traditionally semi-nomadic people living in widely dispersed communities in Amazonian Venezuela and Brazil. Only communities living in the vicinity of a health post have relatively constant access to healthcare. To monitor the improvement in the development of Yanomami healthcare a cross-sectional survey of 183 individuals was conducted to investigate malaria and anaemia prevalence in communities with constant and intermittent access to healthcare. Demographic and clinical data were collected. Malaria was diagnosed by microscopy and haemoglobin concentration by HemoCue. Prevalence of malaria, anaemia, splenomegaly, fever and diarrhoea were all significantly higher in communities with intermittent access to healthcare (anaemia 80.8% vs. 53.6%, P<0.001; malaria 18.2% vs. 6.0%, P=0.013; splenomegaly 85.4% vs.12.5%, P<0.001; fever 50.5% vs. 28.6%, P=0.003; diarrhoea 30.3% vs.10.7% P=0.001). Haemoglobin level (10.0 g/dl vs. 11.5 g/dl) was significantly associated with access to healthcare when controlling for age, sex, malaria and splenomegaly (P=0.01). These findings indicate a heavy burden of anaemia in both areas and the need for interventions against anaemia and malaria, along with more frequent medical visits to remote areas.

Bedside diagnosis of imported malaria using the Binax Now malaria antigen detection test

DEFF Research Database (Denmark)

Wiese, Lothar; Bruun, Brita; Baek, Leif

2006-01-01

Malaria may be misdiagnosed in non-endemic countries when the necessary experience for rapid expert microscopy is lacking. Rapid diagnostic tests may improve the diagnosis and may play a role as a bedside diagnostic tool. In a multicentre study we recruited patients suspected of malaria over...... a period of 14 months. The Binax Now Malaria rapid test was used at the bedside and in the clinical microbiology laboratory. The training of clinical staff was monitored and their experience with the use of the test was recorded. 542 patients were included, 80 of whom had malaria diagnosed by microscopy...... be useful for the diagnosis of P. falciparum malaria when used by routine laboratory staff, but could lead to misdiagnoses when used at the bedside. Microscopy is still essential in order to identify the few missed diagnoses, to determine the degree of parasitaemia, and to ensure species diagnosis...

Malaria in east African highlands during the past 30 years: impact of environmental changes

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Yousif El - Safi Himeidan

2012-08-01

Full Text Available East African highlands are one of the most populated regions in Africa. The population densities in the highlands ranged between 158 persons/km2 in Ethiopia to 410 persons/km2 in Rwanda. According to the United Nations Population Fund, the region has the world's highest population growth rate. These factors are likely behind the high rates of poverty among the populations. As there were no employment opportunities other than agricultural, this demographic pressure of poor populations have included in an extensive unprecedented land use and land cover changes such as modification of bushland, woodland, and grassland on hillsides to farmland and transformation of papyrus swamps in valley bottoms to dairy pastures and cropland and changing of fallows on hillsides from short or seasonal to longer or perennial. Areas harvested for food crops were therefore increased by more than 100% in most of the highlands. The lost of forest areas, mainly due to subsistence agriculture, between 1990 - 2010 ranged between 8000 ha in Rwanda to 2838000 ha in Ethiopia. These unmitigated environmental changes in the highlands led to rise temperature and optimizing the spread and survival of malaria vectors and development of malaria parasites. Malaria in highlands was initially governed by low ambient temperature, trend of malaria transmission was therefore increased and several epidemics were observed in late 1980s and early 2000s. Although, malaria is decreasing through intensified interventions since mid 2000s onwards, these environmental changes might expose population in the highlands of east Africa to an increase risk of malaria and its epidemic particularly if the current interventions are not sustained.

Automated detection of malaria pigment: feasibility for malaria diagnosing in an area with seasonal malaria in northern Namibia

NARCIS (Netherlands)

de Langen, Adrianus J.; van Dillen, Jeroen; de Witte, Piet; Mucheto, Samson; Nagelkerke, Nico; Kager, Piet

2006-01-01

OBJECTIVE: To evaluate the feasibility of automated malaria detection with the Cell-Dyn 3700 (Abbott Diagnostics, Santa Clara, CA, USA) haematology analyser for diagnosing malaria in northern Namibia. METHODS: From April to June 2003, all patients with a positive blood smear result and a subset of

Malaria vectors in Lake Victoria and adjacent habitats in western Kenya.

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Noboru Minakawa

Full Text Available The prevalence of malaria among the residents of the Lake Victoria basin remains high. The environment associated with the lake may maintain a high number of malaria vectors. Lake habitats including water hyacinths have been suspected to be the source of vectors. This study investigated whether malaria vectors breed in the lake habitats and adjacent backwater pools. Anopheline larvae were collected within the littoral zone of the lake and adjacent pools located along approximately 24.3 km of the lakeshore in western Kenya, and their breeding sites characterized. Three primary vector species, Anopheles arabiensis, Anopheles gambiae s.s. and Anopheles funestus s.s., and three potential vectors, were found in the lake habitats. Unexpectedly, An. arabiensis was the most dominant vector species in the lake sampling sites. Its habitats were uncovered or covered with short grass. A potential secondary malaria vector, Anopheles rivulorum, dominated the water hyacinths in the lake. Most breeding sites in the lake were limited to areas that were surrounded by tall emergent plants, including trees, and those not exposed to waves. Nearly half of adjacent habitats were lagoons that were separated from the lake by sand bars. Lagoons contained a variety of microhabitats. Anopheles arabiensis dominated open habitats, whereas An. funestus s.s. was found mainly in vegetated habitats in lagoons. The current study confirmed that several breeding sites are associated with Lake Victoria. Given that Lake Victoria is the second largest lake in the world, the lake related habitats must be extensive; therefore, making targeted vector control difficult. Further exploration is necessary to estimate the effects of lake associated habitats on malaria transmission so as to inform a rational decision-making process for vector control.

Observation of Blood Donor-Recipient Malaria Parasitaemia Patterns in a Malaria Endemic Region

OpenAIRE

Jamilu Abdullahi Faruk; Gboye Olufemi Ogunrinde; Aisha Indo Mamman

2017-01-01

Background. Asymptomatic malaria parasitaemia has been documented in donor blood in West Africa. However, donated blood is not routinely screened for malaria parasites (MPs). The present study therefore aimed to document the frequency of blood transfusion-induced donor-recipient malaria parasitaemia patterns, in children receiving blood transfusion in a tertiary health-centre. Methodology. A cross-sectional, observational study involving 140 children receiving blood transfusion was carried ou...

Malaria and Agriculture in Kenya

International Development Research Centre (IDRC) Digital Library (Canada)

Nancy Minogue

die every day from malaria, conventional efforts to control the disease have not worked. Malaria parasites are .... and other animals. Mosquito nets. Provide insecticide-treated bednets to groups at high risk for malaria, namely young children and pregnant women, through partnerships with nongovernmental organizations ...

MALARIA VACCINE: MYTH OR REALITY?

African Journals Online (AJOL)

Femi Olaleye

Malaria currently remains the highest killer disease nationwide despite existing control measures. Malaria vaccine ... that malaria could be eliminated or at least controlled. However, because of changes in vector behaviour, drug resistance, manpower constraints for public ..... Although animal host models are different from ...

Association of TLR variants with susceptibility to Plasmodium vivax malaria and parasitemia in the Amazon region of Brazil.

Science.gov (United States)

Costa, Allyson Guimarães; Ramasawmy, Rajendranath; Ibiapina, Hiochelson Najibe Santos; Sampaio, Vanderson Souza; Xábregas, Lilyane Amorim; Brasil, Larissa Wanderley; Tarragô, Andréa Monteiro; Almeida, Anne Cristine Gomes; Kuehn, Andrea; Vitor-Silva, Sheila; Melo, Gisely Cardoso; Siqueira, André Machado; Monteiro, Wuelton Marcelo; Lacerda, Marcus Vinicius Guimarães; Malheiro, Adriana

2017-01-01

Plasmodium vivax malaria (Pv-malaria) is still considered a neglected disease despite an alarming number of individuals being infected annually. Malaria pathogenesis occurs with the onset of the vector-parasite-host interaction through the binding of pathogen-associated molecular patterns (PAMPs) and receptors of innate immunity, such as toll-like receptors (TLRs). The triggering of the signaling cascade produces an elevated inflammatory response. Genetic polymorphisms in TLRs are involved in susceptibility or resistance to infection, and the identification of genes involved with Pv-malaria response is important to elucidate the pathogenesis of the disease and may contribute to the formulation of control and elimination tools. A retrospective case-control study was conducted in an intense transmission area of Pv-malaria in the state of Amazonas, Brazil. Genetic polymorphisms (SNPs) in different TLRs, TIRAP, and CD14 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 325 patients infected with P. vivax and 274 healthy individuals without malaria history in the prior 12 months from the same endemic area. Parasite load was determined by qPCR. Simple and multiple logistic/linear regressions were performed to investigate association between the polymorphisms and the occurrence of Pv-malaria and parasitemia. The C/T (TLR5 R392StopCodon) and T/T (TLR9 -1486C/T) genotypes appear to be risk factors for infection by P. vivax (TLR5: C/C vs. C/T [OR: 2.116, 95% CI: 1.054-4.452, p = 0.031]; TLR9: C/C vs. T/T [OR: 1.919, 95% CI: 1.159-3.177, p = 0.010]; respectively). Fever (COEF = 7599.46, 95% CI = 3063.80-12135.12, p = 0.001) and the C/C genotype of TLR9 -1237C/T (COEF = 17006.63, 95% CI = 3472.83-30540.44, p = 0.014) were independently associated with increased parasitemia in patients with Pv-malaria. Variants of TLRs may predispose individuals to infection by P. vivax. The TLR5 R392StopCodon and TLR9 -1486C/T variants

Association of TLR variants with susceptibility to Plasmodium vivax malaria and parasitemia in the Amazon region of Brazil.

Directory of Open Access Journals (Sweden)

Allyson Guimarães Costa

Full Text Available Plasmodium vivax malaria (Pv-malaria is still considered a neglected disease despite an alarming number of individuals being infected annually. Malaria pathogenesis occurs with the onset of the vector-parasite-host interaction through the binding of pathogen-associated molecular patterns (PAMPs and receptors of innate immunity, such as toll-like receptors (TLRs. The triggering of the signaling cascade produces an elevated inflammatory response. Genetic polymorphisms in TLRs are involved in susceptibility or resistance to infection, and the identification of genes involved with Pv-malaria response is important to elucidate the pathogenesis of the disease and may contribute to the formulation of control and elimination tools.A retrospective case-control study was conducted in an intense transmission area of Pv-malaria in the state of Amazonas, Brazil. Genetic polymorphisms (SNPs in different TLRs, TIRAP, and CD14 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis in 325 patients infected with P. vivax and 274 healthy individuals without malaria history in the prior 12 months from the same endemic area. Parasite load was determined by qPCR. Simple and multiple logistic/linear regressions were performed to investigate association between the polymorphisms and the occurrence of Pv-malaria and parasitemia. The C/T (TLR5 R392StopCodon and T/T (TLR9 -1486C/T genotypes appear to be risk factors for infection by P. vivax (TLR5: C/C vs. C/T [OR: 2.116, 95% CI: 1.054-4.452, p = 0.031]; TLR9: C/C vs. T/T [OR: 1.919, 95% CI: 1.159-3.177, p = 0.010]; respectively. Fever (COEF = 7599.46, 95% CI = 3063.80-12135.12, p = 0.001 and the C/C genotype of TLR9 -1237C/T (COEF = 17006.63, 95% CI = 3472.83-30540.44, p = 0.014 were independently associated with increased parasitemia in patients with Pv-malaria.Variants of TLRs may predispose individuals to infection by P. vivax. The TLR5 R392StopCodon and TLR9 -1486C

Willingness to pay for three hypothetical malaria vaccines in Nigeria.

Science.gov (United States)

Udezi, Waka Anthony; Usifoh, Cyril Odianose; Ihimekpen, Omoyeme Oluwatosin

2010-08-01

Unlike some African countries that have reported a approximately 50% reduction in malaria deaths in recent years, Nigeria has shown no evidence of a systematic decline in malaria burden. An important and sustainable reduction in malaria burden cannot be achieved unless an effective and inexpensive malaria vaccine becomes available. The goals of this study were to determine the willingness to pay (WTP) for 3 hypothetical malaria vaccines with different levels of protection (in years), effectiveness, and adverse effects; and to identify factors that influence the price that people are willing to pay in Nigeria. With the aid of a questionnaire, a contingent valuation method using payment cards was used to elicit WTP values for 3 hypothetical malaria vaccines. Payment cards contained both a description of the features of the vaccine being evaluated and price options. The 3 hypothetical vaccines had the following characteristics: vaccine A was 75% effective, protected for 3 years, and was well tolerated; vaccine B was 85% effective, protected for 6 years, and was less well tolerated than vaccine A; and vaccine C was 95% effective and protected for 12 years, but was the least well tolerated. Participants consisted of a convenience sample of individuals who were at the pharmacy waiting area of the state-owned hospitals located in Benin City and Warri, Nigeria. Every third patient or caregiver who was in the pharmacy to fill a prescription was asked to take part in the study as they waited to see the pharmacist. If consent was not granted, the next person in line was approached to be interviewed. Linear multiple regression analysis and nonparametric Kruskal-Wallis, Mann-Whitney, or chi(2) test was applied in inferential analysis, where necessary, to investigate the effects of sociodemographic factors on WTP. Prices on payment cards were expressed in Nigerian naira (NGN 150.00 approximately US $1.00), but study results were expressed in US dollars. A total of 359

Malaria Surveillance - United States, 2014.

Science.gov (United States)

Mace, Kimberly E; Arguin, Paul M

2017-05-26

Malaria in humans is caused by intraerythrocytic protozoa of the genus Plasmodium. These parasites are transmitted by the bite of an infective female Anopheles mosquito. The majority of malaria infections in the United States occur among persons who have traveled to regions with ongoing malaria transmission. However, malaria is occasionally acquired by persons who have not traveled out of the country through exposure to infected blood products, congenital transmission, laboratory exposure, or local mosquitoborne transmission. Malaria surveillance in the United States is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers. This report summarizes cases in persons with onset of illness in 2014 and trends during previous years. Malaria cases diagnosed by blood film, polymerase chain reaction, or rapid diagnostic tests are reported to local and state health departments by health care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System, National Notifiable Diseases Surveillance System, or direct CDC consultations. CDC conducts antimalarial drug resistance marker testing on blood samples submitted by health care providers or local or state health departments. Data from these reporting systems serve as the basis for this report. CDC received reports of 1,724 confirmed malaria cases, including one congenital case and two cryptic cases, with onset of symptoms in 2014 among persons in the United States. The number of confirmed cases in 2014 is consistent with the number of confirmed cases reported in 2013 (n = 1,741; this number has been updated from a previous publication to account for delayed reporting for persons with symptom onset occurring in late 2013). Plasmodium falciparum, P. vivax, P. ovale, and P. malariae were identified in 66.1%, 13.3%, 5.2%, and 2.7% of cases, respectively

Increasing Incidence of Plasmodium knowlesi Malaria following Control of P. falciparum and P. vivax Malaria in Sabah, Malaysia

Science.gov (United States)

William, Timothy; Rahman, Hasan A.; Jelip, Jenarun; Ibrahim, Mohammad Y.; Menon, Jayaram; Grigg, Matthew J.; Yeo, Tsin W.; Anstey, Nicholas M.; Barber, Bridget E.

2013-01-01

Background The simian parasite Plasmodium knowlesi is a common cause of human malaria in Malaysian Borneo and threatens the prospect of malaria elimination. However, little is known about the emergence of P. knowlesi, particularly in Sabah. We reviewed Sabah Department of Health records to investigate the trend of each malaria species over time. Methods Reporting of microscopy-diagnosed malaria cases in Sabah is mandatory. We reviewed all available Department of Health malaria notification records from 1992–2011. Notifications of P. malariae and P. knowlesi were considered as a single group due to microscopic near-identity. Results From 1992–2011 total malaria notifications decreased dramatically, with P. falciparum peaking at 33,153 in 1994 and decreasing 55-fold to 605 in 2011, and P. vivax peaking at 15,857 in 1995 and decreasing 25-fold to 628 in 2011. Notifications of P. malariae/P. knowlesi also demonstrated a peak in the mid-1990s (614 in 1994) before decreasing to ≈100/year in the late 1990s/early 2000s. However, P. malariae/P. knowlesi notifications increased >10-fold between 2004 (n = 59) and 2011 (n = 703). In 1992 P. falciparum, P. vivax and P. malariae/P. knowlesi monoinfections accounted for 70%, 24% and 1% respectively of malaria notifications, compared to 30%, 31% and 35% in 2011. The increase in P. malariae/P. knowlesi notifications occurred state-wide, appearing to have begun in the southwest and progressed north-easterly. Conclusions A significant recent increase has occurred in P. knowlesi notifications following reduced transmission of the human Plasmodium species, and this trend threatens malaria elimination. Determination of transmission dynamics and risk factors for knowlesi malaria is required to guide measures to control this rising incidence. PMID:23359830

The Plasmodium falciparum transcriptome in severe malaria reveals altered expression of genes involved in important processes including surface antigen–encoding var genes

Science.gov (United States)

Tonkin-Hill, Gerry Q.; Trianty, Leily; Noviyanti, Rintis; Nguyen, Hanh H. T.; Sebayang, Boni F.; Lampah, Daniel A.; Marfurt, Jutta; Cobbold, Simon A.; Rambhatla, Janavi S.; McConville, Malcolm J.; Rogerson, Stephen J.; Brown, Graham V.; Day, Karen P.; Price, Ric N.; Anstey, Nicholas M.

2018-01-01

Within the human host, the malaria parasite Plasmodium falciparum is exposed to multiple selection pressures. The host environment changes dramatically in severe malaria, but the extent to which the parasite responds to—or is selected by—this environment remains unclear. From previous studies, the parasites that cause severe malaria appear to increase expression of a restricted but poorly defined subset of the PfEMP1 variant, surface antigens. PfEMP1s are major targets of protective immunity. Here, we used RNA sequencing (RNAseq) to analyse gene expression in 44 parasite isolates that caused severe and uncomplicated malaria in Papuan patients. The transcriptomes of 19 parasite isolates associated with severe malaria indicated that these parasites had decreased glycolysis without activation of compensatory pathways; altered chromatin structure and probably transcriptional regulation through decreased histone methylation; reduced surface expression of PfEMP1; and down-regulated expression of multiple chaperone proteins. Our RNAseq also identified novel associations between disease severity and PfEMP1 transcripts, domains, and smaller sequence segments and also confirmed all previously reported associations between expressed PfEMP1 sequences and severe disease. These findings will inform efforts to identify vaccine targets for severe malaria and also indicate how parasites adapt to—or are selected by—the host environment in severe malaria. PMID:29529020

The ¿/d T-cell response to Plasmodium falciparum malaria in a population in which malaria is endemic

DEFF Research Database (Denmark)

Hviid, L; Kurtzhals, J A; Dodoo, D

1996-01-01

Frequencies and absolute numbers of peripheral gamma/delta T cells have been reported to increase after episodes of Plasmodium falciparum malaria in adults with limited or no previous malaria exposure. In contrast, little is known about the gamma/delta T-cell response to malaria in children from...... areas where malaria is endemic, who bear the burden of malaria-related morbidity and mortality. We investigated the gamma/delta T-cell response in 19 Ghanaian children from an area of hyperendemic, seasonal malaria transmission. The children presented with cerebral malaria (n = 7), severe malarial...... anemia (n = 5), or uncomplicated malaria (n = 7) and were monitored from admission until 4 weeks later. We found no evidence of increased frequencies of gamma/delta T cells in any of the patient groups, whereas one adult expatriate studied in Ghana and three adults admitted to the hospital in Copenhagen...

Phase 1 study in malaria naïve adults of BSAM2/Alhydrogel®+CPG 7909, a blood stage vaccine against P. falciparum malaria.

Directory of Open Access Journals (Sweden)

Ruth D Ellis

Full Text Available A Phase 1 dose escalating study was conducted in malaria naïve adults to assess the safety, reactogenicity, and immunogenicity of the blood stage malaria vaccine BSAM2/Alhydrogel®+ CPG 7909. BSAM2 is a combination of the FVO and 3D7 alleles of recombinant AMA1 and MSP1(42, with equal amounts by weight of each of the four proteins mixed, bound to Alhydrogel®, and administered with the adjuvant CPG 7909. Thirty (30 volunteers were enrolled in two dose groups, with 15 volunteers receiving up to three doses of 40 µg total protein at Days 0, 56, and 180, and 15 volunteers receiving up to three doses of 160 µg protein on the same schedule. Most related adverse events were mild or moderate, but 4 volunteers experienced severe systemic reactions and two were withdrawn from vaccinations due to adverse events. Geometric mean antibody levels after two vaccinations with the high dose formulation were 136 µg/ml for AMA1 and 78 µg/ml for MSP1(42. Antibody responses were not significantly different in the high dose versus low dose groups and did not further increase after third vaccination. In vitro growth inhibition was demonstrated and was closely correlated with anti-AMA1 antibody responses. A Phase 1b trial in malaria-exposed adults is being conducted.Clinicaltrials.gov NCT00889616.

Retrospective genetic study of germinative mutations in Str loci of individuals potentially exposed to ionizing radiation

International Nuclear Information System (INIS)

Costa, Emilia Oliveira Alves

2010-01-01

The Brazilian radiological accident that occurred in 1987, in Goiania, it was a terrible radiation episode. As a consequence, hundreds of people were contaminated due to the Cesium-137 radiation. Recently, many studies had shown that genome instabilities, such as, mutations, chromosomal aberrations, micronuclei formation and micro satellite instability and a delay on cellular death are usually reported on mammal cells exposed to ionizing radiation, being considered as a manly risk to humans. Mutations can be spontaneous, and the occurrence is dependent on the organism, or, induced, being associated to mutagenic exposition. Ionizing radiations are an example of physical and mutagenic agents that could harm the cell repair and could cause the development of many types of cancer. The evaluation of the biological effects of the ionizing radiation, in somatic and germ line cells, with a consequent determination of the radio-induced mutations, it is extremely important to estimate the genetic risks, manly in population exposed to radiation. The analyses of repetitive DNA sequences have been demonstrated that such sequences are prone to high rates of spontaneous mutations. The minisatellites and microsatellites have been used to demonstrate the induction of germ line mutation rates on mouse, humans, among others organisms. The aim of the present study was to analyze the frequency of microsatellite alterations to determine the mutation rates occurred in germ cells of the parents exposed to the ionizing radiation of the Cesium-137. The studied group was constitute of 10 families of individuals accidentally exposed to Cesium-137 and by the control group constituted by 645 healthy individuals who carried out paternity tests on 2009. We found only one mutation of paternal origin in the D8S1179 locus on the exposed group, being the mutation rate of 0.002. In the control group, we found 01 mutation on D16S539 loei and on D3S1358; 02 mutations on Penta E loeus; 04 mutations on D

Malaria burden and control in Bangladesh and prospects for elimination: an epidemiological and economic assessment.

Science.gov (United States)

Haque, Ubydul; Overgaard, Hans J; Clements, Archie C A; Norris, Douglas E; Islam, Nazrul; Karim, Jahirul; Roy, Shyamal; Haque, Waziul; Kabir, Moktadir; Smith, David L; Glass, Gregory E

2014-02-01

Malaria is endemic in 13 of 64 districts in Bangladesh. About 14 million people are at risk. Some evidence suggests that the prevalence of malaria in Bangladesh has decreased since the the Global Fund to Fight AIDS, Tuberculosis and Malaria started to support the National Malaria Control Program (NMCP) in 2007. We did an epidemiological and economic assessment of malaria control in Bangladesh. We obtained annually reported, district-level aggregated malaria case data and information about disbursed funds from the NMCP. We used a Poisson regression model to examine the associations between total malaria, severe malaria, malaria-attributable mortality, and insecticide-treated net coverage. We identified and mapped malaria hotspots using the Getis-Ord Gi* statistic. We estimated the cost-effectiveness of the NMCP by estimating the cost per confirmed case, cost per treated case, and cost per person of insecticide-treated net coverage. During the study period (from Jan 1, 2008, to Dec 31, 2012) there were 285,731 confirmed malaria cases. Malaria decreased from 6.2 cases per 1000 population in 2008, to 2.1 cases per 1000 population in 2012. Prevalence of all malaria decreased by 65% (95% CI 65-66), severe malaria decreased by 79% (78-80), and malaria-associated mortality decreased by 91% (83-95). By 2012, there was one insecticide-treated net for every 2.6 individuals (SD 0.20). Districts with more than 0.5 insecticide-treated nets per person had a decrease in prevalence of 21% (95% CI 19-23) for all malaria, 25% (17-32) for severe malaria, and 76% (35-91) for malaria-associated mortality among all age groups. Malaria hotspots remained in the highly endemic districts in the Chittagong Hill Tracts. The cost per diagnosed case was US$0.39 (SD 0.02) and per treated case was $0.51 (0.27); $0.05 (0.04) was invested per person per year for health education and $0.68 (0.30) was spent per person per year for insecticide-treated net coverage. Malaria elimination is an achievable

Hysteresis in simulations of malaria transmission

Science.gov (United States)

Yamana, Teresa K.; Qiu, Xin; Eltahir, Elfatih A. B.

2017-10-01

Malaria transmission is a complex system and in many parts of the world is closely related to climate conditions. However, studies on environmental determinants of malaria generally consider only concurrent climate conditions and ignore the historical or initial conditions of the system. Here, we demonstrate the concept of hysteresis in malaria transmission, defined as non-uniqueness of the relationship between malaria prevalence and concurrent climate conditions. We show the dependence of simulated malaria transmission on initial prevalence and the initial level of human immunity in the population. Using realistic time series of environmental variables, we quantify the effect of hysteresis in a modeled population. In a set of numerical experiments using HYDREMATS, a field-tested mechanistic model of malaria transmission, the simulated maximum malaria prevalence depends on both the initial prevalence and the initial level of human immunity in the population. We found the effects of initial conditions to be of comparable magnitude to the effects of interannual variability in environmental conditions in determining malaria prevalence. The memory associated with this hysteresis effect is longer in high transmission settings than in low transmission settings. Our results show that efforts to simulate and forecast malaria transmission must consider the exposure history of a location as well as the concurrent environmental drivers.

[Establishment of malaria early warning system in Jiangsu Province II application of digital earth system in malaria epidemic management and surveillance].

Science.gov (United States)

Wang, Wei-Ming; Zhou, Hua-Yun; Liu, Yao-Bao; Li, Ju-Lin; Cao, Yuan-Yuan; Cao, Jun

2013-04-01

To explore a new mode of malaria elimination through the application of digital earth system in malaria epidemic management and surveillance. While we investigated the malaria cases and deal with the epidemic areas in Jiangsu Province in 2011, we used JISIBAO UniStrong G330 GIS data acquisition unit (GPS) to collect the latitude and longitude of the cases located, and then established a landmark library about early-warning areas and an image management system by using Google Earth Free 6.2 and its image processing software. A total of 374 malaria cases were reported in Jiangsu Province in 2011. Among them, there were 13 local vivax malaria cases, 11 imported vivax malaria cases from other provinces, 20 abroad imported vivax malaria cases, 309 abroad imported falciparum malaria cases, 7 abroad imported quartan malaria cases (Plasmodium malaria infection), and 14 abroad imported ovale malaria cases (P. ovale infection). Through the analysis of Google Earth Mapping system, these malaria cases showed a certain degree of aggregation except the abroad imported quartan malaria cases which were highly sporadic. The local vivax malaria cases mainly concentrated in Sihong County, the imported vivax malaria cases from other provinces mainly concentrated in Suzhou City and Wuxi City, the abroad imported vivax malaria cases concentrated in Nanjing City, the abroad imported falciparum malaria cases clustered in the middle parts of Jiangsu Province, and the abroad imported ovale malaria cases clustered in Liyang City. The operation of Google Earth Free 6.2 is simple, convenient and quick, which could help the public health authority to make the decision of malaria prevention and control, including the use of funds and other health resources.

Is there evidence for dual causation between malaria and socioeconomic status? Findings from rural Tanzania.

Science.gov (United States)

Somi, Masha F; Butler, James R G; Vahid, Farshid; Njau, Joseph; Kachur, S Patrick; Abdulla, Salim

2007-12-01

Malaria's relationship with socioeconomic status at the macroeconomic level has been established. This is the first study to explore this relationship at the microeconomic (household) level and estimate the direction of association. Malaria prevalence was measured by parasitemia, and household socioeconomic status was measured using an asset based index. Results from an instrumental variable probit model suggest that socioeconomic status is negatively associated with malaria parasitemia. Other variables that are significantly associated with parasitemia include age of the individual, use of a mosquito net on the night before interview, the number of people living in the household, whether the household was residing at their farm home at the time of interview, household wall construction, and the region of residence. Matching estimators indicate that malaria parasitemia is associated with reduced household socioeconomic status.

Assessing the quality of service of village malaria workers to strengthen community-based malaria control in Cambodia

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Ly Po

2010-04-01

Full Text Available Abstract Background Malaria continues to be a major public health problem in remote forested areas in Cambodia. As a national strategy to strengthen community-based malaria control, the Cambodian government has been running the Village Malaria Worker (VMW project since 2001. This study sought to examine the nature and quality of the VMWs' services. Methods Data collection was carried out in February and March 2008 through interviews with one of the two VMWs who takes the lead in malaria control activities in each of the 315 VMW villages (n = 251. The questionnaire addressed 1 the sociodemographic characteristics of VMWs, 2 service quality, 3 actions for malaria prevention and vector control, and 4 knowledge of malaria epidemiology and vector ecology. Results VMWs were effective in conducting diagnosis with Rapid Diagnostic Tests (RDTs and prescribing anti-malarials to those who had positive RDT results, skills that they had acquired through their training programmes. However, most other services, such as active detection, explanations about compliance, and follow-up of patients, were carried out by only a small proportion of VMWs. The variety of actions that VMWs took for malaria prevention and vector control was small (average action index score 12.8/23, and their knowledge was very limited with less than 20% of the VMWs giving correct answers to six out of seven questions on malaria epidemiology and vector ecology. Knowledge of vector breeding places and malaria transmission were significant determinants of both the quality of VMWs' services and the variety of their actions for malaria prevention and vector control. Conclusions VMWs' services focused primarily on diagnosis and treatment. Their focus needs to be broadened to cover other aspects of malaria control in order to further strengthen community-based malaria control. VMWs' actions and knowledge also need substantial improvement. Strengthening training programmes can help achieve better

A Review of the New European Technical Recommendations for Monitoring Individuals Occupationally Exposed to External Radiation

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Dijk, J.W.E. van; Alves, J.G.; Ambrosi, P.; Bartlett, D.T.; Currivan, L.; Fantuzzi, E.; Kamenopoulou, V.

2013-01-01

This paper reviews the revised Technical Recommendations for Monitoring Individuals Occupationally Exposed to External Radiation as issued by the European Commission as Radiation Protection 160. These recommendations are aimed at all stakeholders in radiation protection dosimetry with an emphasis in the responsible technical staff of approved dosimetry services. This paper briefly touches each Chapter and ends with a more in depth section on the uncertainty evaluation of dose measurements. -- Highlights: ► Recommendations on all aspects of running an approved dosimetry service. ► Radiation protection framework. ► Metrology of personal dosimeters. ► QC and QA of individual monitoring

A longitudinal cohort study of malaria exposure and changing serostatus in a malaria endemic area of rural Tanzania.

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Simmons, Ryan A; Mboera, Leonard; Miranda, Marie Lynn; Morris, Alison; Stresman, Gillian; Turner, Elizabeth L; Kramer, Randall; Drakeley, Chris; O'Meara, Wendy P

2017-08-02

Measurements of anti-malarial antibodies are increasingly used as a proxy of transmission intensity. Most serological surveys are based on the use of cross-sectional data that, when age-stratified, approximates historical patterns of transmission within a population. Comparatively few studies leverage longitudinal data to explicitly relate individual infection events with subsequent antibody responses. The occurrence of seroconversion and seroreversion events for two Plasmodium falciparum asexual stage antigens (MSP-1 and AMA-1) was examined using three annual measurements of 691 individuals from a cohort of individuals in a malaria-endemic area of rural east-central Tanzania. Mixed-effect logistic regression models were employed to determine factors associated with changes in serostatus over time. While the expected population-level relationship between seroprevalence and disease incidence was observed, on an individual level the relationship between individual infections and the antibody response was complex. MSP-1 antibody responses were more dynamic in response to the occurrence and resolution of infection events than AMA-1, while the latter was more correlated with consecutive infections. The MSP-1 antibody response to an observed infection seemed to decay faster over time than the corresponding AMA-1 response. Surprisingly, there was no evidence of an age effect on the occurrence of a conversion or reversion event. While the population-level results concur with previously published sero-epidemiological surveys, the individual-level results highlight the more complex relationship between detected infections and antibody dynamics than can be analysed using cross-sectional data. The longitudinal analysis of serological data may provide a powerful tool for teasing apart the complex relationship between infection events and the corresponding immune response, thereby improving the ability to rapidly assess the success or failure of malaria control programmes.

Malaria Treatment (United States)

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... Providers, Emergency Consultations, and General Public. Contact Us Malaria Treatment (United States) Recommend on Facebook Tweet Share Compartir Treatment of Malaria: Guidelines For Clinicians (United States) Download PDF version ...

Modelling the epidemiological impact of intermittent preventive treatment against malaria in infants.

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Amanda Ross

Full Text Available BACKGROUND: Trials of intermittent preventive treatment against malaria in infants (IPTi using sulphadoxine-pyrimethamine (SP have shown a positive, albeit variable, protective efficacy against clinical malaria episodes. The impact of IPTi in different epidemiological settings and over time is unknown and predictions are hampered by the lack of knowledge about how IPTi works. We investigated mechanisms proposed for the action of IPTi and made predictions of the likely impact on morbidity and mortality. METHODS/PRINCIPAL FINDINGS: We used a comprehensive, individual-based, stochastic model of malaria epidemiology to simulate recently published trials of IPTi using SP with site-specific characteristics as inputs. This baseline model was then modified to represent hypotheses concerning the duration of action of SP, the temporal pattern of fevers caused by individual infections, potential benefits of avoiding fevers on immunity and the effect of sub-therapeutic levels of SP on parasite dynamics. The baseline model reproduced the pattern of results reasonably well. None of the models based on alternative hypotheses improved the fit between the model predictions and observed data. Predictions suggest that IPTi would have a beneficial effect across a range of transmission intensities. IPTi was predicted to avert a greater number of episodes where IPTi coverage was higher, the health system treatment coverage lower, and for drugs which were more efficacious and had longer prophylactic periods. The predicted cumulative benefits were proportionately slightly greater for severe malaria episodes and malaria-attributable mortality than for acute episodes in the settings modelled. Modest increased susceptibility was predicted between doses and following the last dose, but these were outweighed by the cumulative benefits. The impact on transmission intensity was negligible. CONCLUSIONS: The pattern of trial results can be accounted for by differences between

Severe falciparum malaria: A case report

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Arcelia, F.; Asymida, F.; Lubis, N. F. M.; Pasaribu, A. P.

2018-03-01

Plasmodium parasites caused Malaria. Indonesia is one of the countries in Southeast Asia that endemic to malaria. The burden of malaria is more in the eastern part of Indonesia than the Western part as well as the endemicity. Some cases of malaria will develop to severe form. Usually, the manifestation of children and adult are different. We reported a severe case of malaria in a 14-year-old boy who develops several manifestations such as anemia, hypoglycemia, sepsis and black water fever. We successfully treated the patient with Artesunate intravenous and continued with Dihydroartemisinin-piperaquine.

Changes in serum thioredoxin among individuals chronically exposed to arsenic in drinking water

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Li, Yuanyuan; Gao, Yanhui; Zhao, Lijun [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China); Wei, Yudan [Department of Community Medicine, Mercer University School of Medicine, Macon 31207, GA (United States); Feng, Hongqi; Wang, Cheng; Wei, Wei; Ding, Yunpeng [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China); Sun, Dianjun, E-mail: hrbmusdj@163.com [Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Hei Long Jiang Province and Ministry of Health (23618104), Harbin 150081 (China)

2012-02-15

It is well known that oxidative damage plays a key role in the development of chronic arsenicosis. There is a complex set of mechanisms of redox cycling in vivo to protect cells from the damage. In this study, we examined the differences in the levels of serum thioredoxin1 (TRX1) among individuals exposed to different levels of arsenic in drinking water and detected early biomarkers of arsenic poisoning before the appearance of skin lesions. A total of 157 subjects from endemic regions of China were selected and divided into arsenicosis group with skin lesions (total intake of arsenic: 8.68–45.71 mg-year) and non-arsenicosis group without skin lesions, which further divided into low (0.00–1.06 mg-year), medium (1.37–3.55 mg-year), and high (4.26–48.13 mg-year) arsenic exposure groups. Concentrations of serum TRX1 were analyzed by an ELISA method. Levels of water arsenic and urinary speciated arsenics, including inorganic arsenic (iAs), monomethylated arsenic (MMA), and dimethylated arsenic (DMA), were determined by hydride generation atomic absorption spectrometry. Our results showed that the levels of serum TRX1 in arsenicosis patients were significantly higher than that of the subjects who were chronically exposed to arsenic, but without skin lesions. A positive correlation was seen between the levels of serum TRX1 and the total water arsenic intake or the levels of urinary arsenic species. The results of this study indicate that arsenic exposure could significantly change the levels of human serum TRX1, which can be detected before arsenic-specific dermatological symptoms occur. This study provides further evidence on revealing the mechanism of arsenic toxicity. -- Highlights: ► Three regions are selected as the areas affected by endemic arsenicosis of China. ► We first examine changes in serum TRX1 among individuals exposed to arsenic. ► A positive correlation was seen between serum TRX1 and total water arsenic intake. ► The same relationship

Changes in serum thioredoxin among individuals chronically exposed to arsenic in drinking water

International Nuclear Information System (INIS)

Li, Yuanyuan; Gao, Yanhui; Zhao, Lijun; Wei, Yudan; Feng, Hongqi; Wang, Cheng; Wei, Wei; Ding, Yunpeng; Sun, Dianjun

2012-01-01

It is well known that oxidative damage plays a key role in the development of chronic arsenicosis. There is a complex set of mechanisms of redox cycling in vivo to protect cells from the damage. In this study, we examined the differences in the levels of serum thioredoxin1 (TRX1) among individuals exposed to different levels of arsenic in drinking water and detected early biomarkers of arsenic poisoning before the appearance of skin lesions. A total of 157 subjects from endemic regions of China were selected and divided into arsenicosis group with skin lesions (total intake of arsenic: 8.68–45.71 mg-year) and non-arsenicosis group without skin lesions, which further divided into low (0.00–1.06 mg-year), medium (1.37–3.55 mg-year), and high (4.26–48.13 mg-year) arsenic exposure groups. Concentrations of serum TRX1 were analyzed by an ELISA method. Levels of water arsenic and urinary speciated arsenics, including inorganic arsenic (iAs), monomethylated arsenic (MMA), and dimethylated arsenic (DMA), were determined by hydride generation atomic absorption spectrometry. Our results showed that the levels of serum TRX1 in arsenicosis patients were significantly higher than that of the subjects who were chronically exposed to arsenic, but without skin lesions. A positive correlation was seen between the levels of serum TRX1 and the total water arsenic intake or the levels of urinary arsenic species. The results of this study indicate that arsenic exposure could significantly change the levels of human serum TRX1, which can be detected before arsenic-specific dermatological symptoms occur. This study provides further evidence on revealing the mechanism of arsenic toxicity. -- Highlights: ► Three regions are selected as the areas affected by endemic arsenicosis of China. ► We first examine changes in serum TRX1 among individuals exposed to arsenic. ► A positive correlation was seen between serum TRX1 and total water arsenic intake. ► The same relationship

DDT and Malaria Prevention: Addressing the Paradox

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Bouwman, Hindrik; van den Berg, Henk; Kylin, Henrik

2011-01-01

Background The debate regarding dichlorodiphenyltrichloroethane (DDT) in malaria prevention and human health is polarized and can be classified into three positions: anti-DDT, centrist-DDT, pro-DDT. Objective We attempted to arrive at a synthesis by matching a series of questions on the use of DDT for indoor residual spraying (IRS) with literature and insights, and to identify options and opportunities. Discussion Overall, community health is significantly improved through all available malaria control measures, which include IRS with DDT. Is DDT “good”? Yes, because it has saved many lives. Is DDT safe as used in IRS? Recent publications have increasingly raised concerns about the health implications of DDT. Therefore, an unqualified statement that DDT used in IRS is safe is untenable. Are inhabitants and applicators exposed? Yes, and to high levels. Should DDT be used? The fact that DDT is “good” because it saves lives, and “not safe” because it has health and environmental consequences, raises ethical issues. The evidence of adverse human health effects due to DDT is mounting. However, under certain circumstances, malaria control using DDT cannot yet be halted. Therefore, the continued use of DDT poses a paradox recognized by a centrist-DDT position. At the very least, it is now time to invoke precaution. Precautionary actions could include use and exposure reduction. Conclusions There are situations where DDT will provide the best achievable health benefit, but maintaining that DDT is safe ignores the cumulative indications of many studies. In such situations, addressing the paradox from a centrist-DDT position and invoking precaution will help design choices for healthier lives. PMID:21245017

Home-based malaria management in children by women: Evidence from a malaria endemic community in sub-Saharan Africa

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Doreen Nkiru Eugene-Ezebilo

2015-07-01

Full Text Available Objective: To examine the medicines and dosage that mothers who engage in home-based malaria management administer to children aged ≤ 5 years having signs and symptoms associated with malaria and to discuss the possibilities of designing an effective home-based malaria management strategy. Methods: The data were obtained from face-to-face semi-structured interviews conducted with mothers in the Ugbowo Community of Benin City, Nigeria who were selected using multistage systematic random sampling technique. The data were analyzed by qualitative content analysis, arithmetic mean, simple percentages and bar chart. Results: Approximately 90% of the interviewees engaged in home-based malaria management and 10% patronized the hospital. Most of the interviewees who engaged in home-based malaria management administered medicines that stimulates the production of red blood cells and supplies vitamins to children having signs and symptoms of malaria, followed by painkillers and anti-malaria and cough medicine was the least. Of the anti-malaria medicines administered to children, almost 80% of the interviewees administered chloroquine to children, 15% quinine and 3% halfan. Approximately 60% of the interviewees had the correct knowledge of the dosage regime for chloroquine, 38% for quinine and 9% for halfan. Conclusions: Although home-based malaria management is important, it cannot serve as a substitute to the hospital. Some diseases have signs and symptoms that are similar to that of malaria which implies that administering anti-malaria medicines to a child without confirmatory tests might lead to irredeemable complications in that child. If the strategy is to make home-based malaria management effective and sustainable mothers, community health officials should be involved in designing the strategy. Simple rapid diagnostic test kits for malaria should be made available to community health officials and pharmacists so that confirmatory tests could be

A simplified model for predicting malaria entomologic inoculation rates based on entomologic and parasitologic parameters relevant to control.

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Killeen, G F; McKenzie, F E; Foy, B D; Schieffelin, C; Billingsley, P F; Beier, J C

2000-05-01

Malaria transmission intensity is modeled from the starting perspective of individual vector mosquitoes and is expressed directly as the entomologic inoculation rate (EIR). The potential of individual mosquitoes to transmit malaria during their lifetime is presented graphically as a function of their feeding cycle length and survival, human biting preferences, and the parasite sporogonic incubation period. The EIR is then calculated as the product of 1) the potential of individual vectors to transmit malaria during their lifetime, 2) vector emergence rate relative to human population size, and 3) the infectiousness of the human population to vectors. Thus, impacts on more than one of these parameters will amplify each other's effects. The EIRs transmitted by the dominant vector species at four malaria-endemic sites from Papua New Guinea, Tanzania, and Nigeria were predicted using field measurements of these characteristics together with human biting rate and human reservoir infectiousness. This model predicted EIRs (+/- SD) that are 1.13 +/- 0.37 (range = 0.84-1.59) times those measured in the field. For these four sites, mosquito emergence rate and lifetime transmission potential were more important determinants of the EIR than human reservoir infectiousness. This model and the input parameters from the four sites allow the potential impacts of various control measures on malaria transmission intensity to be tested under a range of endemic conditions. The model has potential applications for the development and implementation of transmission control measures and for public health education.

Why use of interventions targeting outdoor biting mosquitoes will be necessary to achieve malaria elimination

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Nicodem James Govella

2012-06-01

Full Text Available By definition, elimination of malaria means permanent reduction to zero of locally incidence of infections. Achieving this goal among other reasons, it requires fully understanding on where and when persons are most exposed to malaria vectors as these are fundamental for targeting interventions to achieve maximum impact. While elimination can be possible in some settings with low malaria transmission intensity and dominated with late and indoor biting of vectors using Long Lasting Insecticidal Nets (LLIN and Indoor Residual Spraying (IRs, it’s difficult and even impossible in areas with high and where majority of human exposure to transmission occurs outside human dwellings. Recently in response to wide spread use of LLIN and IRS, human risk of exposure to transmission is increasingly spread across the entire night so that much of it occurs outdoors and before bed time. This modification of vector populations and behaviour has now been reported from across Africa, Asia and from the Solomon Islands. Historical evidence shows that even in areas with intervention coverage exceeding 90% of human population it was so hard to even push prevalence down below the pre elimination threshold of 1% being compromised mainly with the outdoor residual transmission. Malaria control experts must however continue to deliver interventions that tackle indoor transmission but considerable amount of resources that target mosquitoes outside of houses and outside of sleeping hours will therefore be required to sustain and go beyond existing levels of malaria control and achieve elimination.

Lack of association of interferon regulatory factor 1 with severe malaria in affected child-parental trio studies across three African populations.

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Valentina D Mangano

Full Text Available Interferon Regulatory Factor 1 (IRF-1 is a member of the IRF family of transcription factors, which have key and diverse roles in the gene-regulatory networks of the immune system. IRF-1 has been described as a critical mediator of IFN-gamma signalling and as the major player in driving TH1 type responses. It is therefore likely to be crucial in both innate and adaptive responses against intracellular pathogens such as Plasmodium falciparum. Polymorphisms at the human IRF1 locus have been previously found to be associated with the ability to control P. falciparum infection in populations naturally exposed to malaria. In order to test whether genetic variation at the IRF1 locus also affects the risk of developing severe malaria, we performed a family-based test of association for 18 Single Nucleotide Polymorphisms (SNPs across the gene in three African populations, using genotype data from 961 trios consisting of one affected child and his/her two parents (555 from The Gambia, 204 from Kenya and 202 from Malawi. No significant association with severe malaria or severe malaria subphenotypes (cerebral malaria and severe malaria anaemia was observed for any of the SNPs/haplotypes tested in any of the study populations. Our results offer no evidence that the molecular pathways regulated by the transcription factor IRF-1 are involved in the immune-based pathogenesis of severe malaria.

An open source business model for malaria.

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Årdal, Christine; Røttingen, John-Arne

2015-01-01

Greater investment is required in developing new drugs and vaccines against malaria in order to eradicate malaria. These precious funds must be carefully managed to achieve the greatest impact. We evaluate existing efforts to discover and develop new drugs and vaccines for malaria to determine how best malaria R&D can benefit from an enhanced open source approach and how such a business model may operate. We assess research articles, patents, clinical trials and conducted a smaller survey among malaria researchers. Our results demonstrate that the public and philanthropic sectors are financing and performing the majority of malaria drug/vaccine discovery and development, but are then restricting access through patents, 'closed' publications and hidden away physical specimens. This makes little sense since it is also the public and philanthropic sector that purchases the drugs and vaccines. We recommend that a more "open source" approach is taken by making the entire value chain more efficient through greater transparency which may lead to more extensive collaborations. This can, for example, be achieved by empowering an existing organization like the Medicines for Malaria Venture (MMV) to act as a clearing house for malaria-related data. The malaria researchers that we surveyed indicated that they would utilize such registry data to increase collaboration. Finally, we question the utility of publicly or philanthropically funded patents for malaria medicines, where little to no profits are available. Malaria R&D benefits from a publicly and philanthropically funded architecture, which starts with academic research institutions, product development partnerships, commercialization assistance through UNITAID and finally procurement through mechanisms like The Global Fund to Fight AIDS, Tuberculosis and Malaria and the U.S.' President's Malaria Initiative. We believe that a fresh look should be taken at the cost/benefit of patents particularly related to new malaria

Elimination of Plasmodium falciparum malaria in Tajikistan.

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Kondrashin, Anatoly V; Sharipov, Azizullo S; Kadamov, Dilshod S; Karimov, Saifuddin S; Gasimov, Elkhan; Baranova, Alla M; Morozova, Lola F; Stepanova, Ekaterina V; Turbabina, Natalia A; Maksimova, Maria S; Morozov, Evgeny N

2017-05-30

Malaria was eliminated in Tajikistan by the beginning of the 1960s. However, sporadic introduced cases of malaria occurred subsequently probably as a result of transmission from infected mosquito Anopheles flying over river the Punj from the border areas of Afghanistan. During the 1970s and 1980s local outbreaks of malaria were reported in the southern districts bordering Afghanistan. The malaria situation dramatically changed during the 1990s following armed conflict and civil unrest in the newly independent Tajikistan, which paralyzed health services including the malaria control activities and a large-scale malaria epidemic occurred with more than 400,000 malaria cases. The malaria epidemic was contained by 1999 as a result of considerable financial input from the Government and the international community. Although Plasmodium falciparum constituted only about 5% of total malaria cases, reduction of its incidence was slower than that of Plasmodium vivax. To prevent increase in P. falciparum malaria both in terms of incidence and territory, a P. falciparum elimination programme in the Republic was launched in 200, jointly supported by the Government and the Global Fund for control of AIDS, tuberculosis and malaria. The main activities included the use of pyrethroids for the IRS with determined periodicity, deployment of mosquito nets, impregnated with insecticides, use of larvivorous fishes as a biological larvicide, implementation of small-scale environmental management, and use of personal protection methods by population under malaria risk. The malaria surveillance system was strengthened by the use of ACD, PCD, RCD and selective use of mass blood surveys. All detected cases were timely epidemiologically investigated and treated based on the results of laboratory diagnosis. As a result, by 2009, P. falciparum malaria was eliminated from all of Tajikistan, one year ahead of the originally targeted date. Elimination of P. falciparum also contributed towards

An open source business model for malaria.

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Christine Årdal

Full Text Available Greater investment is required in developing new drugs and vaccines against malaria in order to eradicate malaria. These precious funds must be carefully managed to achieve the greatest impact. We evaluate existing efforts to discover and develop new drugs and vaccines for malaria to determine how best malaria R&D can benefit from an enhanced open source approach and how such a business model may operate. We assess research articles, patents, clinical trials and conducted a smaller survey among malaria researchers. Our results demonstrate that the public and philanthropic sectors are financing and performing the majority of malaria drug/vaccine discovery and development, but are then restricting access through patents, 'closed' publications and hidden away physical specimens. This makes little sense since it is also the public and philanthropic sector that purchases the drugs and vaccines. We recommend that a more "open source" approach is taken by making the entire value chain more efficient through greater transparency which may lead to more extensive collaborations. This can, for example, be achieved by empowering an existing organization like the Medicines for Malaria Venture (MMV to act as a clearing house for malaria-related data. The malaria researchers that we surveyed indicated that they would utilize such registry data to increase collaboration. Finally, we question the utility of publicly or philanthropically funded patents for malaria medicines, where little to no profits are available. Malaria R&D benefits from a publicly and philanthropically funded architecture, which starts with academic research institutions, product development partnerships, commercialization assistance through UNITAID and finally procurement through mechanisms like The Global Fund to Fight AIDS, Tuberculosis and Malaria and the U.S.' President's Malaria Initiative. We believe that a fresh look should be taken at the cost/benefit of patents particularly related

Malaria case in Madagascar, probable implication of a new vector, Anopheles coustani.

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Nepomichene, Thiery N J J; Tata, Etienne; Boyer, Sébastien

2015-12-01

Indoor spraying of insecticides and the use of insecticide-treated bed nets are key strategies for national malaria vector control in the central highlands of Madagascar. During the year 2013, malaria outbreaks were reported by the National Malaria Control Programme in the highlands, including the district of Ankazobe. Entomological trapping was carried out in April and May 2013 and in March 2014, using human landing catches, collection of mosquitoes resting in stables and in houses by oral aspirators, and Centers for Disease Control and Prevention light traps. Detection of Plasmodium in mosquitoes was carried out on head and thorax of anopheline females by ELISA, CSP and PCR (Plasmodium falciparum, Plasmodium malariae, Plasmodium vivax, or Plasmodium ovale). Human biting rate (HBR), sporozoite index and entomological infection rate (EIR) were calculated for Anopheles funestus, Anopheles arabiensis, Anopheles mascarensis, and Anopheles coustani. In Ankazobe district, the presence of malaria vectors such as An. funestus, An. arabiensis and An. mascarensis was confirmed, and a new and abundant potential vector, An. coustani was detected. Indeed, one individual of An. funestus and two An. coustani were detected positive with P. falciparum while one An. mascarensis and four An. coustani were positive with P. vivax. For An. coustani, in March 2014, the EIR varied from 0.01 infectious bites/person/month (ipm) outdoors to 0.11 ipm indoors. For An. funestus, in April 2013, the EIR was 0.13 ipm. The highest HBR value was observed for An. coustani, 86.13 ipm outdoors. The highest sporozoite rate was also for An. coustani, 9.5 % of An. coustani caught in stable was sporozoite positive. The implication of An. coustani in malaria transmission was not previously mentioned in Madagascar. Its very high abundance and the detection of Plasmodium coupled with an opportunistic feeding behaviour in villages with malaria cases supports its role in malaria transmission in Madagascar.

Oral iron supplements for children in malaria-endemic areas

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Neuberger, Ami; Okebe, Joseph; Yahav, Dafna; Paul, Mical

2016-01-01

Background Iron-deficiency anaemia is common during childhood. Iron administration has been claimed to increase the risk of malaria. Objectives To evaluate the effects and safety of iron supplementation, with or without folic acid, in children living in areas with hyperendemic or holoendemic malaria transmission. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library, MEDLINE (up to August 2015) and LILACS (up to February 2015). We also checked the metaRegister of Controlled Trials (mRCT) and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) up to February 2015. We contacted the primary investigators of all included trials, ongoing trials, and those awaiting assessment to ask for unpublished data and further trials. We scanned references of included trials, pertinent reviews, and previous meta-analyses for additional references. Selection criteria We included individually randomized controlled trials (RCTs) and cluster RCTs conducted in hyperendemic and holoendemic malaria regions or that reported on any malaria-related outcomes that included children younger than 18 years of age. We included trials that compared orally administered iron, iron with folic acid, and iron with antimalarial treatment versus placebo or no treatment. We included trials of iron supplementation or fortification interventions if they provided at least 80% of the Recommended Dietary Allowance (RDA) for prevention of anaemia by age. Antihelminthics could be administered to either group, and micronutrients had to be administered equally to both groups. Data collection and analysis The primary outcomes were clinical malaria, severe malaria, and death from any cause. We assessed the risk of bias in included trials with domain-based evaluation and assessed the quality of the evidence using the Grading of Recommendations Assessment

Slow and fast dynamics model of a Malaria with Sickle-Cell genetic disease with multi-stage infections of the mosquitoes population

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Dewi Siawanta, Shanti; Adi-Kusumo, Fajar; Irwan Endrayanto, Aluicius

2018-03-01

Malaria, which is caused by Plasmodium, is a common disease in tropical areas. There are three types of Plasmodium i.e. Plasmodium Vivax, Plasmodium Malariae, and Plasmodium Falciparum. The most dangerous cases of the Malaria are mainly caused by the Plasmodium Falciparum. One of the important characteristics for the Plasmodium infection is due to the immunity of erythrocyte that contains HbS (Haemoglobin Sickle-cell) genes. The individuals who has the HbS gene has better immunity against the disease. In this paper, we consider a model that shows the spread of malaria involving the interaction between the mosquitos population, the human who has HbS genes population and the human with normal gene population. We do some analytical and numerical simulation to study the basic reproduction ratio and the slow-fast dynamics of the phase-portrait. The slow dynamics in our model represents the response of the human population with HbS gene to the Malaria disease while the fast dynamics show the response of the human population with the normal gene to the disease. The slow and fast dynamics phenomena are due to the fact that the population of the individuals who have HbS gene is much smaller than the individuals who has normal genes.

Hemozoin Inhibition and Control of Clinical Malaria

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Chibueze Peter Ihekwereme

2014-01-01

Full Text Available Malaria has a negative impact on health and social and economic life of residents of endemic countries. The ultimate goals of designing new treatment for malaria are to prevent clinical infection, reduce morbidity, and decrease mortality. There are great advances in the understanding of the parasite-host interaction through studies by various scientists. In some of these studies, attempts were made to evaluate the roles of malaria pigment or toxins in the pathogenesis of malaria. Hemozoin is a key metabolite associated with severe malaria anemia (SMA, immunosuppression, and cytokine dysfunction. Targeting of this pigment may be necessary in the design of new therapeutic products against malaria. In this review, the roles of hemozoin in the morbidity and mortality of malaria are highlighted as an essential target in the quest for effective control of clinical malaria.

Disruption of var2csa gene impairs placental malaria associated adhesion phenotype.

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Nicola K Viebig

Full Text Available Infection with Plasmodium falciparum during pregnancy is one of the major causes of malaria related morbidity and mortality in newborn and mothers. The complications of pregnancy-associated malaria result mainly from massive adhesion of Plasmodium falciparum-infected erythrocytes (IE to chondroitin sulfate A (CSA present in the placental intervillous blood spaces. Var2CSA, a member of the P. falciparum erythrocyte membrane protein 1 (PfEMP1 family is the predominant parasite ligand mediating CSA binding. However, experimental evidence suggests that other host receptors, such as hyaluronic acid (HA and the neonatal Fc receptor, may also support placental binding. Here we used parasites in which var2csa was genetically disrupted to evaluate the contribution of these receptors to placental sequestration and to identify additional adhesion receptors that may be involved in pregnancy-associated malaria. By comparison to the wild-type parasites, the FCR3delta var2csa mutants could not be selected for HA adhesion, indicating that var2csa is not only essential for IE cytoadhesion to the placental receptor CSA, but also to HA. However, further studies using different pure sources of HA revealed that the previously observed binding results from CSA contamination in the bovine vitreous humor HA preparation. To identify CSA-independent placental interactions, FCR3delta var2csa mutant parasites were selected for adhesion to the human placental trophoblastic BeWo cell line. BeWo selected parasites revealed a multi-phenotypic adhesion population expressing multiple var genes. However, these parasites did not cytoadhere specifically to the syncytiotrophoblast lining of placental cryosections and were not recognized by sera from malaria-exposed women in a parity dependent manner, indicating that the surface molecules present on the surface of the BeWo selected population are not specifically expressed during the course of pregnancy-associated malaria. Taken

History of malaria research and its contribution to the malaria control success in Suriname: a review

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Breeveld, Florence J. V.; Vreden, Stephen G. S.; Grobusch, Martin P.

2012-01-01

Suriname has cleared malaria from its capital city and coastal areas mainly through the successful use of chloroquine and DDT (dichloro-diphenyl-trichloroethane) during the Global Malaria Eradication programme that started in 1955. Nonetheless, malaria transmission rates remained high in the

Challenges for malaria elimination in Brazil.

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Ferreira, Marcelo U; Castro, Marcia C

2016-05-20

Brazil currently contributes 42 % of all malaria cases reported in the Latin America and the Caribbean, a region where major progress towards malaria elimination has been achieved in recent years. In 2014, malaria burden in Brazil (143,910 microscopically confirmed cases and 41 malaria-related deaths) has reached its lowest levels in 35 years, Plasmodium falciparum is highly focal, and the geographic boundary of transmission has considerably shrunk. Transmission in Brazil remains entrenched in the Amazon Basin, which accounts for 99.5 % of the country's malaria burden. This paper reviews major lessons learned from past and current malaria control policies in Brazil. A comprehensive discussion of the scientific and logistic challenges that may impact malaria elimination efforts in the country is presented in light of the launching of the Plan for Elimination of Malaria in Brazil in November 2015. Challenges for malaria elimination addressed include the high prevalence of symptomless and submicroscopic infections, emerging anti-malarial drug resistance in P. falciparum and Plasmodium vivax and the lack of safe anti-relapse drugs, the largely neglected burden of malaria in pregnancy, the need for better vector control strategies where Anopheles mosquitoes present a highly variable biting behaviour, human movement, the need for effective surveillance and tools to identify foci of infection in areas with low transmission, and the effects of environmental changes and climatic variability in transmission. Control actions launched in Brazil and results to come are likely to influence control programs in other countries in the Americas.

Contribution of the private sector healthcare service providers to malaria diagnosis in a prevention of re-introduction setting.

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Fernando, Sumadhya Deepika; Dharmawardana, Priyani; Epasinghe, Geethanee; Senanayake, Niroshana; Rodrigo, Chaturaka; Premaratne, Risintha; Wickremasinghe, Rajitha

2016-10-18

Sri Lanka is currently in the prevention of re-introduction phase of malaria. The engagement of the private sector health care institutions in malaria surveillance is important. The purpose of the study was to determine the number of diagnostic tests carried out, the number of positive cases identified and the referral system for diagnosis in the private sector and to estimate the costs involved. This prospective study of private sector laboratories within the Colombo District of Sri Lanka was carried out over a 6-month period in 2015. The management of registered private sector laboratories was contacted individually and the purpose of the study was explained. A reporting format was developed and introduced for monthly reporting. Forty-one laboratories were eligible to be included in the study and 28 participated by reporting data on a monthly basis. Excluding blood bank samples and routine testing for foreign employment, malaria diagnostic tests were carried out on 973 individuals during the 6-month period and nine malaria cases were identified. In 2015, a total of 36 malaria cases were reported from Sri Lanka. Of these, 24 (67 %) were diagnosed in the Colombo District and 50 % of them were diagnosed in private hospitals. An equal number of cases were diagnosed from the private sector and government sector in the Colombo District in 2015. The private sector being a major contributor in the detection of imported malaria cases in the country should be actively engaged in the national malaria surveillance system.

Local topographic wetness indices predict household malaria risk better than land-use and land-cover in the western Kenya highlands.

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Cohen, Justin M; Ernst, Kacey C; Lindblade, Kim A; Vulule, John M; John, Chandy C; Wilson, Mark L

2010-11-16

Identification of high-risk malaria foci can help enhance surveillance or control activities in regions where they are most needed. Associations between malaria risk and land-use/land-cover are well-recognized, but these environmental characteristics are closely interrelated with the land's topography (e.g., hills, valleys, elevation), which also influences malaria risk strongly. Parsing the individual contributions of land-cover/land-use variables to malaria risk requires examining these associations in the context of their topographic landscape. This study examined whether environmental factors like land-cover, land-use, and urban density improved malaria risk prediction based solely on the topographically-determined context, as measured by the topographic wetness index. The topographic wetness index, an estimate of predicted water accumulation in a defined area, was generated from a digital terrain model of the landscape surrounding households in two neighbouring western Kenyan highland communities. Variables determined to best encompass the variance in this topographic wetness surface were calculated at a household level. Land-cover/land-use information was extracted from a high-resolution satellite image using an object-based classification method. Topographic and land-cover variables were used individually and in combination to predict household-level malaria in the communities through an iterative split-sample model fitting and testing procedure. Models with only topographic variables were compared to those with additional predictive factors related to land-cover/land-use to investigate whether these environmental factors improved prediction of malaria based on the shape of the land alone. Variables related to topographic wetness proved most useful in predicting the households of individuals contracting malaria in this region of rugged terrain. Other variables related to human modification of the environment also demonstrated clear associations with

Local topographic wetness indices predict household malaria risk better than land-use and land-cover in the western Kenya highlands

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Vulule John M

2010-11-01

Full Text Available Abstract Background Identification of high-risk malaria foci can help enhance surveillance or control activities in regions where they are most needed. Associations between malaria risk and land-use/land-cover are well-recognized, but these environmental characteristics are closely interrelated with the land's topography (e.g., hills, valleys, elevation, which also influences malaria risk strongly. Parsing the individual contributions of land-cover/land-use variables to malaria risk requires examining these associations in the context of their topographic landscape. This study examined whether environmental factors like land-cover, land-use, and urban density improved malaria risk prediction based solely on the topographically-determined context, as measured by the topographic wetness index. Methods The topographic wetness index, an estimate of predicted water accumulation in a defined area, was generated from a digital terrain model of the landscape surrounding households in two neighbouring western Kenyan highland communities. Variables determined to best encompass the variance in this topographic wetness surface were calculated at a household level. Land-cover/land-use information was extracted from a high-resolution satellite image using an object-based classification method. Topographic and land-cover variables were used individually and in combination to predict household-level malaria in the communities through an iterative split-sample model fitting and testing procedure. Models with only topographic variables were compared to those with additional predictive factors related to land-cover/land-use to investigate whether these environmental factors improved prediction of malaria based on the shape of the land alone. Results Variables related to topographic wetness proved most useful in predicting the households of individuals contracting malaria in this region of rugged terrain. Other variables related to human modification of the

Choosing a Drug to Prevent Malaria

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... Malaria About Malaria FAQs Fast Facts Disease Biology Ecology Human Factors Sickle Cell Mosquitoes Parasites Where Malaria ... medicines, also consider the possibility of drug-drug interactions with other medicines that the person might be ...

Predicting the impact of insecticide-treated bed nets on malaria transmission: the devil is in the detail

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Novak Robert J

2009-11-01

Full Text Available Abstract Background Insecticide-treated bed nets (ITNs, including long-lasting insecticidal nets (LLINs, play a primary role in global campaigns to roll back malaria in tropical Africa. Effectiveness of treated nets depends on direct impacts on individual mosquitoes including killing and excite-repellency, which vary considerably among vector species due to variations in host-seeking behaviours. While monitoring and evaluation programmes of ITNs have focuses on morbidity and all-cause mortality in humans, local entomological context receives little attention. Without knowing the dynamics of local vector species and their responses to treated nets, it is difficult to predict clinical outcomes when ITN applications are scaled up across African continent. Sound model frameworks incorporating intricate interactions between mosquitoes and treated nets are needed to develop the predictive capacity for scale-up applications of ITNs. Methods An established agent-based model was extended to incorporate the direct outcomes, e.g. killing and avoidance, of individual mosquitoes exposing to ITNs in a hypothetical village setting with 50 houses and 90 aquatic habitats. Individual mosquitoes were tracked throughout the life cycle across the landscape. Four levels of coverage, i.e. 40, 60, 80 and 100%, were applied at the household level with treated houses having only one bed net. By using Latin hypercube sampling scheme, parameters governing killing, diverting and personal protection of net users were evaluated for their relative roles in containing mosquito populations, entomological inoculation rates (EIRs and malaria incidence. Results There were substantial gaps in coverage between households and individual persons, and 100% household coverage resulted in circa 50% coverage of the population. The results show that applications of ITNs could give rise to varying impacts on population-level metrics depending on values of parameters governing interactions of

Predicting the impact of insecticide-treated bed nets on malaria transmission: the devil is in the detail.

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Gu, Weidong; Novak, Robert J

2009-11-16

Insecticide-treated bed nets (ITNs), including long-lasting insecticidal nets (LLINs), play a primary role in global campaigns to roll back malaria in tropical Africa. Effectiveness of treated nets depends on direct impacts on individual mosquitoes including killing and excite-repellency, which vary considerably among vector species due to variations in host-seeking behaviours. While monitoring and evaluation programmes of ITNs have focuses on morbidity and all-cause mortality in humans, local entomological context receives little attention. Without knowing the dynamics of local vector species and their responses to treated nets, it is difficult to predict clinical outcomes when ITN applications are scaled up across African continent. Sound model frameworks incorporating intricate interactions between mosquitoes and treated nets are needed to develop the predictive capacity for scale-up applications of ITNs. An established agent-based model was extended to incorporate the direct outcomes, e.g. killing and avoidance, of individual mosquitoes exposing to ITNs in a hypothetical village setting with 50 houses and 90 aquatic habitats. Individual mosquitoes were tracked throughout the life cycle across the landscape. Four levels of coverage, i.e. 40, 60, 80 and 100%, were applied at the household level with treated houses having only one bed net. By using Latin hypercube sampling scheme, parameters governing killing, diverting and personal protection of net users were evaluated for their relative roles in containing mosquito populations, entomological inoculation rates (EIRs) and malaria incidence. There were substantial gaps in coverage between households and individual persons, and 100% household coverage resulted in circa 50% coverage of the population. The results show that applications of ITNs could give rise to varying impacts on population-level metrics depending on values of parameters governing interactions of mosquitoes and treated nets at the individual level

Malaria parasite carriage and risk determinants in a rural population: a malariometric survey in Rwanda.

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Kateera, Fredrick; Mens, Petra F; Hakizimana, Emmanuel; Ingabire, Chantal M; Muragijemariya, Liberata; Karinda, Parfait; Grobusch, Martin P; Mutesa, Leon; van Vugt, Michèle

2015-01-21

Based on routine health facility case data, Rwanda has achieved a significant malaria burden reduction in the past ten years. However, community-based malaria parasitaemia burden and reasons for continued residual infections, despite a high coverage of control interventions, have yet to be characterized. Measurement of malaria parasitaemia rates and evaluation of associated risk factors among asymptomatic household members in a rural community in Rwanda were conducted. A malariometric household survey was conducted between June and November 2013, involving 12,965 persons living in 3,989 households located in 35 villages in a sector in eastern Rwanda. Screening for malaria parasite carriage and collection of demographic, socio-economic, house structural features, and prior fever management data, were performed. Logistic regression models with adjustment for within- and between-households clustering were used to assess malaria parasitaemia risk determinants. Overall, malaria parasitaemia was found in 652 (5%) individuals, with 518 (13%) of households having at least one parasitaemic member. High malaria parasite carriage risk was associated with being male, child or adolescent (age group 4-15), reported history of fever and living in a household with multiple occupants. A malaria parasite carriage risk-protective effect was associated with living in households of, higher socio-economic status, where the head of household was educated and where the house floor or walls were made of cement/bricks rather than mud/earth/wood materials. Parasitaemia cases were found to significantly cluster in the Gikundamvura area that neighbours marshlands. Overall, Ruhuha Sector can be classified as hypo-endemic, albeit with a particular 'cell of villages' posing a higher risk for malaria parasitaemia than others. Efforts to further reduce transmission and eventually eliminate malaria locally should focus on investments in programmes that improve house structure features (that limit

Remotely Sensed Environmental Conditions and Malaria Mortality in Three Malaria Endemic Regions in Western Kenya.

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Maquins Odhiambo Sewe

Full Text Available Malaria is an important cause of morbidity and mortality in malaria endemic countries. The malaria mosquito vectors depend on environmental conditions, such as temperature and rainfall, for reproduction and survival. To investigate the potential for weather driven early warning systems to prevent disease occurrence, the disease relationship to weather conditions need to be carefully investigated. Where meteorological observations are scarce, satellite derived products provide new opportunities to study the disease patterns depending on remotely sensed variables. In this study, we explored the lagged association of Normalized Difference Vegetation Index (NVDI, day Land Surface Temperature (LST and precipitation on malaria mortality in three areas in Western Kenya.The lagged effect of each environmental variable on weekly malaria mortality was modeled using a Distributed Lag Non Linear Modeling approach. For each variable we constructed a natural spline basis with 3 degrees of freedom for both the lag dimension and the variable. Lag periods up to 12 weeks were considered. The effect of day LST varied between the areas with longer lags. In all the three areas, malaria mortality was associated with precipitation. The risk increased with increasing weekly total precipitation above 20 mm and peaking at 80 mm. The NDVI threshold for increased mortality risk was between 0.3 and 0.4 at shorter lags.This study identified lag patterns and association of remote- sensing environmental factors and malaria mortality in three malaria endemic regions in Western Kenya. Our results show that rainfall has the most consistent predictive pattern to malaria transmission in the endemic study area. Results highlight a potential for development of locally based early warning forecasts that could potentially reduce the disease burden by enabling timely control actions.

Cerebral malaria: susceptibility weighted MRI

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Vinit Baliyan

2015-03-01

Full Text Available Cerebral malaria is one of the fatal complications of Plasmodium falciparum infection. Pathogenesis involves cerebral microangiopathy related to microvascular plugging by infected red blood cells. Conventional imaging with MRI and CT do not reveal anything specific in case of cerebral malaria. Susceptibility weighted imaging, a recent advance in the MRI, is very sensitive to microbleeds related to microangiopathy. Histopathological studies in cerebral malaria have revealed microbleeds in brain parenchyma secondary to microangiopathy. Susceptibility weighted imaging, being exquisitely sensitive to microbleeds may provide additional information and improve the diagnostic accuracy of MRI in cerebral malaria.

Malaria in Dielmo, a Senegal village: Is its elimination possible after seven years of implementation of long-lasting insecticide-treated nets?

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Amélé Nyedzie Wotodjo

Full Text Available The malaria burden has decreased significantly in recent years in Africa through the widespread use of artemisinin-based combination therapy (ACT and long-lasting insecticide-treated nets (LLINs. However, the occurrence of malaria resurgences, the loss of immunity of exposed populations constitute among other factors, serious concerns about the future of malaria elimination efforts. This study investigated the evolution of malaria morbidity in Dielmo (Senegal before and after the implementation of LLINs.A longitudinal study was carried out in Dielmo over eight years, from July 2007 to July 2015. In July 2008, LLINs were offered to all villagers, and in July 2011 and August 2014 the LLINs were renewed. A survey on LLINs use was done each quarter of the year. Thick smears stained with Giemsa, a rapid diagnostic test (RDT and quantitative polymerase chain reaction (PCR methods were performed for all cases of fever to assess malaria clinical attacks. Malaria cases were treated with ACT since June 2006.Malaria morbidity has decreased significantly since the implementation of LLINs in Dielmo, together with ACT. However, malaria resurgences have occurred twice during the seven years of LLINs use. These resurgences occurred the first time during the third year after the introduction of LLINs (aIRR (adjusted incidence-rate ratio [95%CI] = 5.90 [3.53; 9.88] p< 0.001 and a second time during the third year after the renewal of LLINs (aIRR [95%CI] = 5.60 [3.34; 9.39] p< 0.001. Sixty-nine percent (69% of the nets tested for their long-lasting insecticidal activity remained effective after 3 years of use.Good management of malaria cases by the use of ACT as first-line treatment against malaria in addition to the use of LLINs has significantly reduced malaria in Dielmo and allowed to reach the phase of pre-elimination of the disease. However, the occurrence of malaria resurgences raised serious concerns about malaria elimination, which would require additional

Housing Improvements and Malaria Risk in Sub-Saharan Africa: A Multi-Country Analysis of Survey Data.

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Lucy S Tusting

2017-02-01

Full Text Available Improvements to housing may contribute to malaria control and elimination by reducing house entry by malaria vectors and thus exposure to biting. We tested the hypothesis that the odds of malaria infection are lower in modern, improved housing compared to traditional housing in sub-Saharan Africa (SSA.We analysed 15 Demographic and Health Surveys (DHS and 14 Malaria Indicator Surveys (MIS conducted in 21 countries in SSA between 2008 and 2015 that measured malaria infection by microscopy or rapid diagnostic test (RDT. DHS/MIS surveys record whether houses are built with finished materials (e.g., metal or rudimentary materials (e.g., thatch. This information was used to develop a binary housing quality variable where houses built using finished wall, roof, and floor materials were classified as "modern", and all other houses were classified as "traditional". Conditional logistic regression was used to determine the association between housing quality and prevalence of malaria infection in children aged 0-5 y, adjusting for age, gender, insecticide-treated net (ITN use, indoor residual spraying, household wealth, and geographic cluster. Individual survey odds ratios (ORs were combined to determine a summary OR using a random effects meta-analysis. Of 284,532 total children surveyed, 139,318 were tested for malaria infection using microscopy (n = 131,652 or RDT (n = 138,540. Within individual surveys, malaria prevalence measured by microscopy ranged from 0.4% (Madagascar 2011 to 45.5% (Burkina Faso 2010 among children living in modern houses and from 0.4% (The Gambia 2013 to 70.6% (Burkina Faso 2010 in traditional houses, and malaria prevalence measured by RDT ranged from 0.3% (Senegal 2013-2014 to 61.2% (Burkina Faso 2010 in modern houses and from 1.5% (The Gambia 2013 to 79.8% (Burkina Faso 2010 in traditional houses. Across all surveys, modern housing was associated with a 9% to 14% reduction in the odds of malaria infection (microscopy

Alternative transmission routes in the malaria elimination era: an overview of transfusion-transmitted malaria in the Americas.

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Alho, Regina M; Machado, Kim Vinícius Amaral; Val, Fernando F A; Fraiji, Nelson A; Alexandre, Marcia A A; Melo, Gisely C; Recht, Judith; Siqueira, André M; Monteiro, Wuelton M; Lacerda, Marcus V G

2017-02-15

Transfusion-transmitted (TT) malaria is an alternative infection route that has gained little attention from authorities, despite representing a life-threatening condition. There has been no systematic review of this health problem in American countries. The aim of this study was to describe the clinical and epidemiological characteristics of TT malaria in the Americas and identify factors associated with lethality based on the studies published in the literature. Potentially relevant papers in all languages were retrieved from MEDLINE and LILACS. Additional articles were obtained from reviews and original papers. Publications on screening of candidate blood donors and on surveillance of TT malaria cases were included. Odds ratios with respective 95% confidence intervals (95% CI) were calculated. Epidemiological characteristics of blood donors of TT malaria cases, including a pooled positivity of different tests for malaria diagnosis, were retrieved. A total of 63 publications regarding TT malaria from seven countries were included, from 1971 to 2016. A total of 422 cases of TT malaria were recorded. Most TT malaria cases were in females (62.0%) and 39.5% were in the ≥61 years-old age group. About half of all cases were from Mexico (50.7%), 40.3% from the United States of America (USA) and 6.6% from Brazil. Gyneco-obstetrical conditions (67.3%), surgical procedures (20.6%) and complications from neoplasias (6.1%) were the most common indications of transfusion. Packed red blood cells (RBCs) (50.7%) and whole blood (43.3%) were the blood products mostly associated with TT malaria. Cases were mostly caused by Plasmodium malariae (58.4%), followed by Plasmodium vivax (20.7%) and Plasmodium falciparum (17.9%). A total of 66.6% of cases were diagnosed by microscopy. Incubation period of 2-3 weeks was the most commonly observed (28.6%). Lethality was seen in 5.3% of cases and was associated with living in non-endemic countries, P. falciparum infection and concomitant

Integrating child health services into malaria control services of village malaria workers in remote Cambodia: service utilization and knowledge of malaria management of caregivers.

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Hasegawa, Aya; Yasuoka, Junko; Ly, Po; Nguon, Chea; Jimba, Masamine

2013-08-23

Malaria and other communicable diseases remain major threats in developing countries. In Cambodia, village malaria workers (VMWs) have been providing malaria control services in remote villages to cope with the disease threats. In 2009, the VMW project integrated child health services into the original malaria control services. However, little has been studied about the utilization of VMWs' child health services. This study aimed to identify determinants of caregivers' VMW service utilization for childhood illness and caregivers' knowledge of malaria management. A cross-sectional study was conducted in 36 VMW villages of Kampot and Kampong Thom provinces in July-September 2012. An equal number of VMW villages with malaria control services only (M) and those with malaria control plus child health services (M+C) were selected from each province. Using structured questionnaires, 800 caregivers of children under five and 36 VMWs, one of the two VMWs who was providing VMW services in each study village were interviewed. Among the caregivers, 23% in M villages and 52% in M+C villages utilized VMW services for childhood illnesses. Determinants of caregivers' utilization of VMWs in M villages included their VMWs' length of experience (AOR = 11.80, 95% confidence interval [CI] = 4.46-31.19) and VMWs' service quality (AOR = 2.04, CI = 1.01-4.11). In M+C villages, VMWs' length of experience (AOR = 2.44, CI = 1.52-3.94) and caregivers' wealth index (AOR = 0.35, CI = 0.18-0.68) were associated with VMW service utilization. Meanwhile, better service quality of VMWs (AOR = 3.21, CI = 1.34-7.66) and caregivers' literacy (AOR = 9.91, CI = 4.66-21.05) were positively associated with caregivers' knowledge of malaria management. VMWs' service quality and length of experience are important determinants of caregivers' utilization of VMWs' child health services and their knowledge of malaria management. Caregivers are seeking VMWs' support for childhood illnesses even if they are

Population hemoglobin mean and anemia prevalence in Papua New Guinea: new metrics for defining malaria endemicity?

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Nicolas Senn

Full Text Available BACKGROUND: The hypothesis is that hemoglobin-based metrics are useful tools for estimating malaria endemicity and for monitoring malaria control strategies. The aim of this study is to compare population hemoglobin mean and anemia prevalence to established indicators of malaria endemicity, including parasite rates, rates of enlarged spleens in children, and records of (presumptive malaria diagnosis among populations living with different levels of malaria transmission. METHODOLOGY/PRINCIPAL FINDINGS: Convenience sample, multisite cross-sectional household surveys conducted in Papua New Guinea. Correlations (r(2 between population Hb mean and anemia prevalence and altitude, parasite rate, and spleen rate were investigated in children ages 2 to 10 years, and in the general population; 21,664 individuals from 156 different communities were surveyed. Altitude ranged from 5 to 2120 meters. In young children, correlations between altitude and parasite rate, population Hb mean, anemia prevalence, and spleen rate were high (r(2: -0.77, 0.73, -0.81, and -0.68; p1500 m (p<0.001. CONCLUSIONS/SIGNIFICANCE: In PNG, where Plasmodium vivax accounts for an important part of all malaria infections, population hemoglobin mean and anemia prevalence correlate well with altitude, parasite, and spleen rates. Hb measurement is simple and affordable, and may be a useful new tool, alone or in association with other metrics, for estimating malaria endemicity and monitoring effectiveness of malaria control programs. Further prospective studies in areas with different malaria epidemiology and different factors contributing to the burden of anemia are warranted to investigate the usefulness of Hb metrics in monitoring malaria transmission intensity.

Immunomodulation by heavy metals tested individually or in mixtures in rainbow trout (Oncorhynchus mykiss) exposed in vivo

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Sanchez-Dardon, J.; Voccia, I.; Hontela, A.; Chilmonczyk, S.; Dunier, M.; Boermans, H.; Blakley, B.; Fournier, M.

1999-07-01

The objective of this study was to evaluate the effect of heavy metals, at environmentally relevant concentrations, on the immune response of rainbow trout. Trout were exposed for 30 d to cadmium chloride (CdCl{sub 2}), mercuric chloride (HgCl{sub 2}), or zinc chloride (ZnCl{sub 2}) either individually or in combinations: CdCl{sub 2}/HgCl{sub 2}, CdCl{sub 2}/ZnCl{sub 2}, HgCl{sub 2}/ZnCl{sub 2}, or CdCl{sub 2}/HgCl{sub 2}/ZnCl{sub 2}. Following the 30-d exposure, parameters of the nonspecific cellular immune response (phagocytosis, respiratory burst, and lymphoblastic proliferation) and of the nonspecific humoral immune response (lysozyme activity and the level of immunoglobulin) were measured. The results obtained indicate that individually, all three metals induce significant immunomodulations. However, the toxicity of mercury or cadmium is significantly reduced in fish simultaneously exposed to zinc, indicating that a protection is afforded by zinc against cadmium- and mercury-induced immunotoxicity.

Challenges for modelling spatio-temporal variations of malaria risk in Malawi

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Lowe, R.; Chirombo, J.; Tompkins, A. M.

2012-04-01

Malaria is the leading cause of morbidity and mortality in Malawi with more than 6 million episodes reported each year. Malaria poses a huge economic burden to Malawi in terms of the direct cost of treating malaria patients and also indirect costs resulting from workdays lost in agriculture and industry and absenteeism from school. Malawi implements malaria control activities within the Roll Back Malaria framework, with the objective to provide those most at risk (i.e. children under five years, pregnant woman and individuals with suppressed immune systems) access to personal and community protective measures. However, at present there is no mechanism by which to target the most 'at risk' populations ahead of an impending epidemic. Malaria transmission is influenced by variations in meteorological conditions, which impact the biology of the mosquito and the availability of breeding sites, but also socio-economic conditions such as levels of urbanisation, poverty and education, which influence human vulnerability and vector habitat. The many potential drivers of malaria, both extrinsic, such as climate, and intrinsic, such as population immunity are often difficult to disentangle. This presents a challenge for modelling of malaria risk in space and time. Using an age-stratified spatio-temporal dataset of malaria cases at the district level from July 2004 - June 2011, we use a spatio-temporal modelling framework to model variations in malaria risk in Malawi. Climatic and topographic variations are accounted for using an interpolation method to relate gridded products to administrative districts. District level data is tested in the model to account for confounding factors, including the proportion of the population living in urban areas; residing in traditional housing; with no toilet facilities; who do not attend school, etc, the number of health facilities per population and yearly estimates of insecticide-treated mosquito net distribution. In order to account for

Barriers to prompt and effective malaria treatment among the poorest population in Kenya

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Okungu Vincent

2010-05-01

Full Text Available Abstract Background Prompt access to effective malaria treatment is central to the success of malaria control worldwide, but few fevers are treated with effective anti-malarials within 24 hours of symptoms onset. The last two decades saw an upsurge of initiatives to improve access to effective malaria treatment in many parts of sub-Saharan Africa. Evidence suggests that the poorest populations remain least likely to seek prompt and effective treatment, but the factors that prevent them from accessing interventions are not well understood. With plans under way to subsidize ACT heavily in Kenya and other parts of Africa, there is urgent need to identify policy actions to promote access among the poor. This paper explores access barriers to effective malaria treatment among the poorest population in four malaria endemic districts in Kenya. Methods The study was conducted in the poorest areas of four malaria endemic districts in Kenya. Multiple data collection methods were applied including: a cross-sectional survey (n = 708 households; 24 focus group discussions; semi-structured interviews with health workers (n = 34; and patient exit interviews (n = 359. Results Multiple factors related to affordability, acceptability and availability interact to influence access to prompt and effective treatment. Regarding affordability, about 40 percent of individuals who self-treated using shop-bought drugs and 42 percent who visited a formal health facility reported not having enough money to pay for treatment, and having to adopt coping strategies including borrowing money and getting treatment on credit in order to access care. Other factors influencing affordability were seasonality of illness and income sources, transport costs, and unofficial payments. Regarding acceptability, the major interrelated factors identified were provider patient relationship, patient expectations, beliefs on illness causation, perceived effectiveness of treatment, distrust in

Towards a strategy for malaria in pregnancy in Afghanistan: analysis of clinical realities and women's perceptions of malaria and anaemia.

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Howard, Natasha; Enayatullah, Sayed; Mohammad, Nader; Mayan, Ismail; Shamszai, Zohra; Rowland, Mark; Leslie, Toby

2015-11-04

Afghanistan has some of the worst maternal and infant mortality indicators in the world and malaria is a significant public health concern. Study objectives were to assess prevalence of malaria and anaemia, related knowledge and practices, and malaria prevention barriers among pregnant women in eastern Afghanistan. Three studies were conducted: (1) a clinical survey of maternal malaria, maternal anaemia, and neonatal birthweight in a rural district hospital delivery-ward; (2) a case-control study of malaria risk among reproductive-age women attending primary-level clinics; and (3) community surveys of malaria and anaemia prevalence, socioeconomic status, malaria knowledge and reported behaviour among pregnant women. Among 517 delivery-ward participants (1), one malaria case (prevalence 1.9/1000), 179 anaemia cases (prevalence 346/1000), and 59 low-birthweight deliveries (prevalence 107/1000) were detected. Anaemia was not associated with age, gravidity, intestinal parasite prevalence, or low-birthweight at delivery. Among 141 malaria cases and 1010 controls (2), no association was found between malaria infection and pregnancy (AOR 0.89; 95 % CI 0.57-1.39), parity (AOR 0.95; 95 % CI 0.85-1.05), age (AOR 1.02; 95 % CI 1.00-1.04), or anaemia (AOR 1.00; 95 % CI 0.65-1.54). Those reporting insecticide-treated net usage had 40 % reduced odds of malaria infection (AOR 0.60; 95 % CI 0.40-0.91). Among 530 community survey participants (3), malaria and anaemia prevalence were 3.9/1000 and 277/1000 respectively, with 34/1000 experiencing severe anaemia. Despite most women having no formal education, malaria knowledge was high. Most expressed reluctance to take malaria preventive medication during pregnancy, deeming it potentially unsafe. Given the low malaria risk and reported avoidance of medication during pregnancy, intermittent preventive treatment is hard to justify or implement. Preventive strategy should instead focus on long-lasting insecticidal nets for all pregnant

Maps of the Sri Lanka malaria situation preceding the tsunami and key aspects to be considered in the emergency phase and beyond

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Konradsen Flemming

2005-01-01

Full Text Available Abstract Background Following the tsunami, a detailed overview of the area specific transmission levels is essential in assessing the risk of malaria in Sri Lanka. Recent information on vector insecticide resistance, parasite drug resistance, and insights into the national policy for malaria diagnosis and treatment are important in assisting national and international agencies in their control efforts. Methods Monthly records over the period January 1995 – October 2004 of confirmed malaria cases were used to perform an analysis of malaria distribution at district spatial resolution. Also, a focused review of published reports and routinely collected information was performed. Results The incidence of malaria was only 1 case per thousand population in the 10 months leading up to the disaster, in the districts with the highest transmission. Conclusion Although relocated people may be more exposed to mosquito bites, and their capacity to handle diseases affected, the environmental changes caused by the tsunami are unlikely to enhance breeding of the principal vector, and, given the present low parasite reservoir, the likelihood of a malaria outbreak is low. However, close monitoring of the situation is necessary, especially as December – February is normally the peak transmission season. Despite some losses, the Sri Lanka public health system is capable of dealing with the possible threat of a malaria outbreak after the tsunami. The influx of foreign medical assistance, drugs, and insecticides may interfere with malaria surveillance, and the long term malaria control strategy of Sri Lanka, if not in accordance with government policy.

Malaria in inter-war British India.

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Bynum, W F

2000-06-01

British India was an important site of much important malaria research. Although Ronald Ross left India in 1899, a number of malariologists continued the task of evaluating the incidence and distribution of malaria in the country. Implementing practical solutions was hampered by formidable social and economic problems. This paper examines the Indian situation in the late 1920s, through a retrospective selection of writings chosen by J.A. Sinton for reproduction in an early issue of 'The records of the malaria survey of India', and the analysis of the Indian malaria situation through a visit of the League of Nations Malaria Commission in 1929.

Immunoinformatics of Placental Malaria Vaccine Development

DEFF Research Database (Denmark)

Jessen, Leon Eyrich

Malaria is an infectious disease caused by a protozoan parasite of the genus Plasmodium, which is transferred by female Anopheles mosquitos. WHO estimates that in 2012 there were 207 million cases of malaria, of which 627,000 were fatal. People living in malaria-endemic areas, gradually acquire...... immunity with multiple infections. Placental malaria (PM) is caused by P. falciparum sequestering in the placenta of pregnant women due to the presence of novel receptors in the placenta. An estimated 200,000 infants die a year as a result of PM. In 2004 the specific protein responsible...... and development in the field of placental malaria vaccine development....

Epidemiological characterization of Plasmodium falciparum in the Republic of Cabo Verde: implications for potential large-scale re-emergence of malaria

Science.gov (United States)

Alves, Joana; Roque, Ana Luísa; Cravo, Pedro; Valdez, Tomás; Jelinek, Tomas; do Rosário, Virgílio E; Arez, Ana Paula

2006-01-01

Background Malaria has come near eradication at archipelago of Cabo Verde in 1970. Infections are now only observed in Santiago, where outbreaks occur. In these islands, malaria is considered by the international community as being of limited risk and, therefore, no prophylaxis is recommended. Since the understanding of factors that determine malaria outbreaks are crucial for controlling the disease, the present study aimed to investigate if the malaria infections observed in Santiago Island are maintained in isolated foci and in asymptomatic individuals. Methods The occurrence of asymptomatic carriers in villages with history of malaria as well as the level of exposure of these populations were investigated using PCR and serological analyses. Results Results indicate that malaria is maintained as asymptomatic and sub-patent infections and that the majority of the circulating parasite populations harbour chloroquine-resistant mutations. Conclusion These observations highlight the alarming prospect of malaria to become a serious public health problem and underscore the need for a tighter surveillance. PMID:16630349

[Malaria in Poland in 2010].

Science.gov (United States)

Stepień, Małgorzata

2012-01-01

The objective of this study was to describe the epidemiology of imported malaria in Poland in 2010 in comparison to previous years. The study included malaria cases that were collected and registered by the State Sanitary Inspection in 2010 in Poland. Data reported was verified, processed and published by National Institute of Public Health - National Institute of Hygiene. All cases were laboratory confirmed by blood film, polymerase chain reaction or rapid diagnostic tests outlined by the EU case definition. Differences in the distribution of demographic, parasitological and clinical characteristics, and incidence were analyzed. In 2010, a total of 35 confirmed malaria cases were notified in Poland, 13 more than 2009. All cases were imported, 49% from Africa, including 1 case with relapsing malaria caused by P. vivax and 2 cases of recrudescence falciparum malaria following failure of treatment. The number of cases acquired in Asia (37% of the total), mainly from India and Indonesia, was significantly higher than observed in previous years. Among cases with species-specific diagnosis 19 (63%) were caused by P. falciparum, 9 (30%) by P. vivax, one by P. ovale and one by P. malariae. The median age of all cases was 42 years (range 9 months to 71 years), males comprised 69% of patients, females 31%, three patients were Indian citizens temporarily in Poland. Common reasons for travel to endemic countries were tourism (57%), work-related visits (37%), one person visited family and in one case the reason for travel was unknown. Sixteen travelers took chemoprophylaxis, but only three of them appropriately (adherence to the recommended drug regimen, continuation upon return and use of appropriate medicines). In 2010, there were no deaths due to malaria and clinical course of disease was severe in 7 cases. When compared with 2009, there was a marked increase in the number of imported malaria cases in Poland, however the total number of notified cases remained low. Serious

Hidden burden of malaria in Indian women

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Sharma Vinod P

2009-12-01

Full Text Available Abstract Malaria is endemic in India with an estimated 70-100 million cases each year (1.6-1.8 million reported by NVBDCP; of this 50-55% are Plasmodium vivax and 45-50% Plasmodium falciparum. A recent study on malaria in pregnancy reported from undivided Madhya Pradesh state (includes Chhattisgarh state, that an estimated over 220,000 pregnant women contract malaria infection each year. Malaria in pregnancy caused- abortions 34.5%; stillbirths 9%; and maternal deaths 0.45%. Bulk of this tragic outcome can be averted by following the Roll Back Malaria/WHO recommendations of the use of malaria prevention i.e. indoor residual spraying (IRS/insecticide-treated bed nets (ITN preferably long-lasting treated bed nets (LLIN; intermittent preventive therapy (IPT; early diagnosis, prompt and complete treatment using microscopic/malaria rapid diagnostics test (RDT and case management. High incidence in pregnancy has arisen because of malaria surveillance lacking coverage, lack of age and sex wise data, staff shortages, and intermittent preventive treatment (IPT applicable in high transmission states/pockets is not included in the national drug policy- an essential component of fighting malaria in pregnancy in African settings. Inadequate surveillance and gross under-reporting has been highlighted time and again for over three decades. As a result the huge problem of malaria in pregnancy reported occasionally by researchers has remained hidden. Malaria in pregnancy may quicken severity in patients with drug resistant parasites, anaemia, endemic poverty, and malnutrition. There is, therefore, urgent need to streamline malaria control strategies to make a difference in tackling this grim scenario in human health.

Malaria control in the African Region: perceptions and viewspoints on proceedings of the Africa Leaders Malaria Alliance (ALMA

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Sambo Luis

2011-06-01

Full Text Available Abstract Background In 2009 a total of 153,408 malaria deaths were reported in Africa. Eleven countries showed a reduction of more than 50% in either confirmed malaria cases or malaria admissions and deaths in recent years. However, many African countries are not on track to achieve the malaria component of the Millennium Development Goal (MDG 6. The African Leaders Malaria Alliance (ALMA working session at the 15th African Union Summit discussed the bottlenecks to achieving MDG 6 (specifically halting and beginning to reverse the incidence of malaria by 2015, success factors, and what countries needed to do to accelerate achievement of the MDG. The purpose of this article is to reflect on the proceedings of the ALMA working session. Methods Working methods of the session included speeches and statements by invited speakers and high-level panel discussions. Discussion The main bottlenecks identified related to the capacity of the health systems to deliver quality care and accessibility issues; need for strong, decentralized malaria-control programmes with linkages with other health and development sectors, the civil society and private sector entities; benefits of co-implementation of malaria control programmes with child survival or other public health interventions; systematic application of integrated promotive, preventive, diagnostic and case management interventions with full community participation; adapting approaches to local political, socio-cultural and administrative environments. The following prerequisites for success were identified: a clear vision and effective leadership of national malaria control programmes; high level political commitment to ensure adequate capacity in expertise, skill mix and number of managers, technicians and service providers; national ownership, intersectoral collaboration and accountability, as well as strong civil society and private sector involvement; functional epidemiological surveillance systems

Can slide positivity rates predict malaria transmission?

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Bi Yan

2012-04-01

Full Text Available Abstract Background Malaria is a significant threat to population health in the border areas of Yunnan Province, China. How to accurately measure malaria transmission is an important issue. This study aimed to examine the role of slide positivity rates (SPR in malaria transmission in Mengla County, Yunnan Province, China. Methods Data on annual malaria cases, SPR and socio-economic factors for the period of 1993 to 2008 were obtained from the Center for Disease Control and Prevention (CDC and the Bureau of Statistics, Mengla, China. Multiple linear regression models were conducted to evaluate the relationship between socio-ecologic factors and malaria incidence. Results The results show that SPR was significantly positively associated with the malaria incidence rates. The SPR (β = 1.244, p = 0.000 alone and combination (SPR, β = 1.326, p  Conclusion SPR is a strong predictor of malaria transmission, and can be used to improve the planning and implementation of malaria elimination programmes in Mengla and other similar locations. SPR might also be a useful indicator of malaria early warning systems in China.

Air pollution and vulnerability of exposed individuals: the case of downtown Medellín

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Gabriel J. González

2012-02-01

Full Text Available The presence of respiratory problems in high level pollution areas is linked to factors such as exposure, susceptibility, and social coping. Objective: To present statistical evidence regarding the relationship between the probability of experiencing symptoms or contracting a respiratory disease and factors such as exposure to pollution, susceptibility, and social coping among people inhabiting areas with particulate matter pollution. Methodology: The study used unique information collected from a survey conducted on 1000 people in downtown Medellin who were exposed to this problem. This information was used to perform a descriptive statistic analysis and to build 27 probit models. The dependent variables were: the patient has a symptom or disease –emf-, the patient has a symptom –leve-, and the patient has a respiratory disease –grave-. Results: The results evidence that exposure is a key variable affecting the presence of respiratory symptoms or diseases (vulnerability; however, exposed individuals may also experience health problems not only due to air pollution per se, but also to implicit personal and social conditions.

Insecticide-treated nets for the prevention of malaria in pregnancy: a systematic review of randomised controlled trials.

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Carol Gamble

2007-03-01

Full Text Available BACKGROUND: Protection from malaria with insecticide-treated bednets (ITNs during pregnancy is widely advocated, but evidence of benefit has been inconsistent. We undertook a systematic review of randomised trials. METHODS AND FINDINGS: Three cluster-randomised and two individually randomised trials met the inclusion criteria; four from Africa (n = 6,418 and one from Thailand (n = 223. In Africa, ITNs compared to no nets increased mean birth weight by 55 g (95% confidence interval [CI] 21-88, reduced low birth weight by 23% (relative risk [RR] 0.77, 95% CI 0.61-0.98, and reduced miscarriages/stillbirths by 33% (RR 0.67, 0.47-0.97 in the first few pregnancies. Placental parasitaemia was reduced by 23% in all gravidae (RR 0.77, 0.66-0.90. The effects were apparent in the cluster-randomised trials and the one individually randomised trial in Africa. The trial in Thailand, which randomised individuals to ITNs or untreated nets, showed reductions in anaemia and fetal loss in all gravidae, but not reductions in clinical malaria or low birth weight. CONCLUSIONS: ITNs used throughout pregnancy or from mid-pregnancy onwards have a beneficial impact on pregnancy outcome in malaria-endemic Africa in the first few pregnancies. The potential impact of ITNs in pregnant women and their newborns in malaria regions outside Africa requires further research.

Within-host selection of drug resistance in a mouse model of repeated incomplete malaria treatment : Comparison between atovaquone and pyrimethamine

NARCIS (Netherlands)

Nuralitha, Suci; Siregar, Josephine E.; Syafruddin, Din; Roelands, Jessica; Verhoef, Jan; Hoepelman, Andy I M; Marzuki, Sangkot

2016-01-01

The evolutionary selection of malaria parasites within individual hosts is an important factor in the emergence of drug resistance but is still not well understood. We have examined the selection process for drug resistance in the mouse malaria agent Plasmodium berghei and compared the dynamics of

Malaria and Vascular Endothelium

Energy Technology Data Exchange (ETDEWEB)

Alencar, Aristóteles Comte Filho de, E-mail: aristoteles.caf@gmail.com [Universidade Federal do Amazonas, Manaus, AM (Brazil); Lacerda, Marcus Vinícius Guimarães de [Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), Manaus, AM (Brazil); Okoshi, Katashi; Okoshi, Marina Politi [Faculdade de Medicina de Botucatu (Unesp), Botucatu, SP (Brazil)

2014-08-15

Involvement of the cardiovascular system in patients with infectious and parasitic diseases can result from both intrinsic mechanisms of the disease and drug intervention. Malaria is an example, considering that the endothelial injury by Plasmodium-infected erythrocytes can cause circulatory disorders. This is a literature review aimed at discussing the relationship between malaria and endothelial impairment, especially its effects on the cardiovascular system. We discuss the implications of endothelial aggression and the interdisciplinarity that should guide the malaria patient care, whose acute infection can contribute to precipitate or aggravate a preexisting heart disease.

Malaria and Vascular Endothelium

International Nuclear Information System (INIS)

Alencar, Aristóteles Comte Filho de; Lacerda, Marcus Vinícius Guimarães de; Okoshi, Katashi; Okoshi, Marina Politi

2014-01-01

Involvement of the cardiovascular system in patients with infectious and parasitic diseases can result from both intrinsic mechanisms of the disease and drug intervention. Malaria is an example, considering that the endothelial injury by Plasmodium-infected erythrocytes can cause circulatory disorders. This is a literature review aimed at discussing the relationship between malaria and endothelial impairment, especially its effects on the cardiovascular system. We discuss the implications of endothelial aggression and the interdisciplinarity that should guide the malaria patient care, whose acute infection can contribute to precipitate or aggravate a preexisting heart disease

Management of imported malaria in Europe

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Askling Helena H

2012-09-01

Full Text Available Abstract In this position paper, the European Society for Clinical Microbiology and Infectious Diseases, Study Group on Clinical Parasitology, summarizes main issues regarding the management of imported malaria cases. Malaria is a rare diagnosis in Europe, but it is a medical emergency. A travel history is the key to suspecting malaria and is mandatory in patients with fever. There are no specific clinical signs or symptoms of malaria although fever is seen in almost all non-immune patients. Migrants from malaria endemic areas may have few symptoms. Malaria diagnostics should be performed immediately on suspicion of malaria and the gold- standard is microscopy of Giemsa-stained thick and thin blood films. A Rapid Diagnostic Test (RDT may be used as an initial screening tool, but does not replace urgent microscopy which should be done in parallel. Delays in microscopy, however, should not lead to delayed initiation of appropriate treatment. Patients diagnosed with malaria should usually be hospitalized. If outpatient management is preferred, as is the practice in some European centres, patients must usually be followed closely (at least daily until clinical and parasitological cure. Treatment of uncomplicated Plasmodium falciparum malaria is either with oral artemisinin combination therapy (ACT or with the combination atovaquone/proguanil. Two forms of ACT are available in Europe: artemether/lumefantrine and dihydroartemisinin/piperaquine. ACT is also effective against Plasmodium vivax, Plasmodium ovale, Plasmodium malariae and Plasmodium knowlesi, but these species can be treated with chloroquine. Treatment of persistent liver forms in P. vivax and P. ovale with primaquine is indicated after excluding glucose 6 phosphate dehydrogenase deficiency. There are modified schedules and drug options for the treatment of malaria in special patient groups, such as children and pregnant women. The potential for drug interactions and the role of food in the

Plasmodium coatneyi in Rhesus Macaques Replicates the Multisystemic Dysfunction of Severe Malaria in Humans

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Cabrera-Mora, Monica; Garcia, AnaPatricia; Orkin, Jack; Strobert, Elizabeth; Barnwell, John W.; Galinski, Mary R.

2013-01-01

Severe malaria, a leading cause of mortality among children and nonimmune adults, is a multisystemic disorder characterized by complex clinical syndromes that are mechanistically poorly understood. The interplay of various parasite and host factors is critical in the pathophysiology of severe malaria. However, knowledge regarding the pathophysiological mechanisms and pathways leading to the multisystemic disorders of severe malaria in humans is limited. Here, we systematically investigate infections with Plasmodium coatneyi, a simian malaria parasite that closely mimics the biological characteristics of P. falciparum, and develop baseline data and protocols for studying erythrocyte turnover and severe malaria in greater depth. We show that rhesus macaques (Macaca mulatta) experimentally infected with P. coatneyi develop anemia, coagulopathy, and renal and metabolic dysfunction. The clinical course of acute infections required suppressive antimalaria chemotherapy, fluid support, and whole-blood transfusion, mimicking the standard of care for the management of severe malaria cases in humans. Subsequent infections in the same animals progressed with a mild illness in comparison, suggesting that immunity played a role in reducing the severity of the disease. Our results demonstrate that P. coatneyi infection in rhesus macaques can serve as a highly relevant model to investigate the physiological pathways and molecular mechanisms of malaria pathogenesis in naïve and immune individuals. Together with high-throughput postgenomic technologies, such investigations hold promise for the identification of new clinical interventions and adjunctive therapies. PMID:23509137

T-cell responses in malaria

DEFF Research Database (Denmark)

Hviid, L; Jakobsen, P H; Abu-Zeid, Y A

1992-01-01

Malaria is caused by infection with protozoan parasites of the genus Plasmodium. It remains one of the most severe health problems in tropical regions of the world, and the rapid spread of resistance to drugs and insecticides has stimulated intensive research aimed at the development of a malaria...... vaccine. Despite this, no efficient operative vaccine is currently available. A large amount of information on T-cell responses to malaria antigens has been accumulated, concerning antigens derived from all stages of the parasite life cycle. The present review summarizes some of that information......, and discusses factors affecting the responses of T cells to malaria antigens....

Micro-heterogeneity of malaria transmission in the Peruvian Amazon: a baseline assessment underlying a population-based cohort study.

Science.gov (United States)

Rosas-Aguirre, Angel; Guzman-Guzman, Mitchel; Gamboa, Dionicia; Chuquiyauri, Raul; Ramirez, Roberson; Manrique, Paulo; Carrasco-Escobar, Gabriel; Puemape, Carmen; Llanos-Cuentas, Alejandro; Vinetz, Joseph M

2017-08-04

Understanding the dynamics of malaria transmission in diverse endemic settings is key for designing and implementing locally adapted and sustainable control and elimination strategies. A parasitological and epidemiological survey was conducted in September-October 2012, as a baseline underlying a 3-year population-based longitudinal cohort study. The aim was to characterize malaria transmission patterns in two contrasting ecological rural sites in the Peruvian Amazon, Lupuna (LUP), a riverine environment, and Cahuide (CAH), associated with road-linked deforestation. After a full population census, 1941 individuals 3 years and older (829 in LUP, 1112 in CAH) were interviewed, clinically examined and had a blood sample taken for the detection of malaria parasites by microscopy and PCR. Species-specific parasite prevalence was estimated overall and by site. Multivariate logistic regression models assessed risk factors for parasite infection by PCR, while SaTScan detected spatial clusters of PCR-positive individuals within each site. In addition, data from routine malaria surveillance in the period 2009-2012 were obtained. Parasite prevalence by PCR was higher in CAH than in LUP for Plasmodium vivax (6.2% vs. 3.9%) and for Plasmodium falciparum (2.6% vs. 1.2%). Among PCR-confirmed infections, asymptomatic (Asy) parasite carriers were always more common than symptomatic (Sy) infections for P. vivax (Asy/Sy ratio: 2/1 in LUP and 3.7/1 in CAH) and for P. falciparum (Asy/Sy ratio: 1.3/1 in LUP and 4/1 in CAH). Sub-patent (Spat) infections also predominated over patent (Pat) infections for both species: P. vivax (Spat/Pat ratio: 2.8/1 in LUP and 3.7/1 in CAH) and P. falciparum malaria (Spat/Pat ratio: 1.9/1 in LUP and 26/0 in CAH). For CAH, age, gender and living in a household without electricity were significantly associated with P. vivax infection, while only age and living in a household with electricity was associated with P. falciparum infection. For LUP, only

Identifying malaria hotspots in Keur Soce health and demographic surveillance site in context of low transmission.

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Ndiath, Mansour; Faye, Babacar; Cisse, Badara; Ndiaye, Jean Louis; Gomis, Jules François; Dia, Anta Tal; Gaye, Oumar

2014-11-24

Malaria is major public health problem in Senegal. In some parts of the country, it occurs almost permanently with a seasonal increase during the rainy season. There is evidence to suggest that the prevalence of malaria in Senegal has decreased considerably during the past few years. Recent data from the Senegalese National Malaria Control Programme (NMCP) indicates that the number of malaria cases decrease from 1,500,000 in 2006 to 174,339 in 2010. With the decline of malaria morbidity in Senegal, the characterization of the new epidemiological profile of this disease is crucial for public health decision makers. SaTScan™ software using the Kulldorf method of retrospective space-time permutation and the Bernoulli purely spatial model was used to identify malaria clusters using confirmed malaria cases in 74 villages. ArcMAp was used to map malaria hotspots. Logistic regression was used to investigate risk factors for malaria hotspots in Keur Soce health and demographic surveillance site. A total of 1,614 individuals in 440 randomly selected households were enrolled. The overall malaria prevalence was 12%. The malaria prevalence during the study period varied from less than 2% to more than 25% from one village to another. The results showed also that rooms located between 50 m to 100 m away from livestock holding place [adjusted O.R = 0.7, P = 0.044, 95% C.I (1.02 - 7.42)], bed net use [adjusted O.R = 1.2, P = 0.024, 95% C.I (1.02 -1.48)], are good predictors for malaria hotspots in the Keur Soce health and demographic surveillance site. The socio economic status of the household also predicted on hotspots patterns. The less poor household are 30% less likely to be classified as malaria hotspots area compared to the poorest household [adjusted O.R = 0.7, P = 0.014, 95% C.I (0.47 - 0.91)]. The study investigated risk factors for malaria hotspots in small communities in the Keur Soce site. The result showed considerable variation of malaria

Acceptability by community health workers in Senegal of combining community case management of malaria and seasonal malaria chemoprevention

DEFF Research Database (Denmark)

Tine, Roger Ck; Ndiaye, Pascal; Ndour, Cheikh T

2013-01-01

Community case management of malaria (CCMm) and seasonal malaria chemoprevention (SMC) are anti-malarial interventions that can lead to substantial reduction in malaria burden acting in synergy. However, little is known about the social acceptability of these interventions. A study was undertaken...... to assess whether combining the interventions would be an acceptable approach to malaria control for community health workers (CHWs)....

Important advances in malaria vaccine research

Directory of Open Access Journals (Sweden)

Priyanka Jadhav

2012-01-01

Full Text Available Malaria is one of the most widespread parasitic infection in Asian countries affecting the poor of the poor. In an effort to develop an effective vaccine for the treatment of malaria, various attempts are being made worldwide. If successful, such a vaccine can be effective for treatment of both Plasmodium vivax and Plasmodium falciparum. This would also be able to avoid complications such as drug resistance, resistance to insecticides, nonadherence to the treatment schedule, and eventually high cost of treatment in the resource-limited settings. In the current compilation, the details from the literature were collected by using PubMed and Medline as search engines and searched for terms such as malaria, vaccine, and malaria treatment. This review collates and provides glimpses of the information on the recent malaria vaccine development. The reader will be taken through the historical perspective followed by the approaches to the malaria vaccine development from pre-erythrocytic stage vaccines, asexual stage vaccines, transmission blocking vaccines, etc. Looking at the current scenario of the malaria and treatment strategies, it is an absolute need of an hour that an effective malaria vaccine should be developed. This would bring a revolutionary breakthrough in the treatment modalities especially when there is increasing emergence of resistance to existing drug therapy. It would be of great purpose to serve those living in malaria endemic region and also for travelers which are nonimmune and coming to malaria endemic region. As infection by P. vivax is more prevalent in India and other Asian subcontinent and is often prominent in areas where elimination is being attempted, special consideration is required of the role of vaccines in blocking transmission, regardless of the stages being targeted. Development of vaccines is feasible but with the support of private sector and government organization in terms of regulatory and most importantly

Factors impeding the acceptability and use of malaria preventive measures: implications for malaria elimination in eastern Rwanda

NARCIS (Netherlands)

Ingabire, Chantal Marie; Rulisa, Alexis; van Kempen, Luuk; Muvunyi, Claude; Koenraadt, Constantianus J. M.; van Vugt, Michele; Mutesa, Leon; van den Borne, Bart; Alaii, Jane

2015-01-01

Long-lasting insecticidal nets (LLIN), indoor residual spraying (IRS) and malaria case treatment with artemisinin-based combination therapy (ACT) have been proven to significantly reduce malaria, but may not necessarily lead to malaria elimination. This study explored factors hindering the

Impact of folate supplementation on the efficacy of sulfadoxine/pyrimethamine in preventing malaria in pregnancy: the potential of 5-methyl-tetrahydrofolate.

Science.gov (United States)

Nzila, Alexis; Okombo, John; Molloy, Anne M

2014-02-01

Malaria remains the leading cause of mortality and morbidity in children under the age of 5 years and pregnant women. To counterbalance the malaria burden in pregnancy, an intermittent preventive treatment strategy has been developed. This is based on the use of the antifolate sulfadoxine/pyrimethamine, taken at specified intervals during pregnancy, and reports show that this approach reduces the malaria burden in pregnancy. Pregnancy is also associated with the risk of neural tube defects (NTDs), especially in women with low folate status, and folic acid supplementation is recommended in pregnancy to lower the risk of NTDs. Thus, in malaria-endemic areas, pregnant women have to take both antifolate medication to prevent malaria and folic acid to lower the risk of NTDs. However, the concomitant use of folate and antifolate is associated with a decrease in antifolate efficacy, exposing pregnant women to malaria. Thus, there is genuine concern that this strategy may not be appropriate. We have reviewed work carried out on malaria folate metabolism and antifolate efficacy in the context of folate supplementation. This review shows that: (i) the folate supplementation effect on antifolate efficacy is dose-dependent, and folic acid doses required to protect pregnant women from NTDs will not decrease antifolate activity; and (ii) 5-methyl-tetrahydrofolate, the predominant form of folate in the blood circulation, could be administered (even at high dose) concomitantly with antifolate without affecting antifolate efficacy. Thus, strategies exist to protect pregnant women from malaria while maintaining adequate folate levels in the body to reduce the occurrence of NTDs.

Malaria programme personnel's experiences, perceived barriers and facilitators to implementing malaria elimination strategy in South Africa.

Science.gov (United States)

Hlongwana, Khumbulani Welcome; Sartorius, Benn; Tsoka-Gwegweni, Joyce

2018-01-10

South Africa has set an ambitious goal targeting to eliminate malaria by 2018, which is consistent with the United Nations Sustainable Development Goals' call to end the epidemic of malaria by 2030 across the globe. There are conflicting views regarding the feasibility of malaria elimination, and furthermore studies investigating malaria programme personnel's perspectives on strategy implementation are lacking. The study was a cross-sectional survey conducted in 2014 through a face-to-face investigator-administered semi-structured questionnaire to all eligible and consenting malaria programme personnel (team leader to senior manager levels) in three malaria endemic provinces (KwaZulu-Natal, Mpumalanga, and Limpopo) of South Africa. The overall response rate was 88.6% (148/167) among all eligible malaria personnel. The mean age of participants was 47 years (SD 9.7, range 27-70), and the mean work experience of 19.4 years (SD 11.1, range 0-42). The majority were male (78.4%), and 66.9% had secondary level education. Awareness of the malaria elimination policy was high (99.3%), but 89% contended that they were never consulted when the policy was formulated and few had either seen (29.9%) or read (23%) the policy, either in full or in part. Having read the policy was positively associated with professional job designations (managers, EHPs and entomologists) (p = 0.010) and tertiary level education (p = 0.042). There was a sentiment that the policy was neither sufficiently disseminated to all key healthcare workers (76.4%) nor properly adapted (68.9%) for the local operational context in the elimination strategy. Most (89.1%) participants were not optimistic about eliminating malaria by 2018, as they viewed the elimination strategy in South Africa as too theoretical with unrealistic targets. Other identified barriers included inadequate resources (53.5%) and high cross-border movements (19.8%). Most participants were not positive that South Africa could achieve

Advances and challenges in malaria vaccine development.

Science.gov (United States)

Crompton, Peter D; Pierce, Susan K; Miller, Louis H

2010-12-01

Malaria caused by Plasmodium falciparum remains a major public health threat, especially among children and pregnant women in Africa. An effective malaria vaccine would be a valuable tool to reduce the disease burden and could contribute to elimination of malaria in some regions of the world. Current malaria vaccine candidates are directed against human and mosquito stages of the parasite life cycle, but thus far, relatively few proteins have been studied for potential vaccine development. The most advanced vaccine candidate, RTS,S, conferred partial protection against malaria in phase II clinical trials and is currently being evaluated in a phase III trial in Africa. New vaccine targets need to be identified to improve the chances of developing a highly effective malaria vaccine. A better understanding of the mechanisms of naturally acquired immunity to malaria may lead to insights for vaccine development.

Cytogenetic study of in utero exposed individuals, 2

Energy Technology Data Exchange (ETDEWEB)

Itoh, Masahiro; Honda, Takeo

1986-11-01

In 20 persons exposed in uterus to atomic radiation, chromosomes in the peripheral lymphocytes were examined using G-band differential staining and conventional Giemsa staining techniques. The subjects were divided into Group A of the mothers receiving 17 - 535 rad and Group B of the mothers receiving 0 rad. Chromosome aberrations were observed in 72 (5%) of 1,463 cells in Group A and in 19 (1%) of 1503 cells in Group B. Most of the chromosome aberrations were stable type involving translocation, inversion, and deletion. In one person whose mother was exposed to 453 rad, structural chromosome aberrations were observed in 53 (38%) of 141 cells. Furthermore, 11 cells had two kinds of clones. This finding may provide clues for elucidating the promotion of cloning of cells with stable type structural chromosome aberrations due to in uterus exposure to high doses of atomic radiation. (Namekawa, K.).

Cytogenetic study of in utero exposed individuals, 2

International Nuclear Information System (INIS)

Itoh, Masahiro; Honda, Takeo

1986-01-01

In 20 persons exposed in uterus to atomic radiation, chromosomes in the peripheral lymphocytes were examined using G-band differential staining and conventional Giemsa staining techniques. The subjects were divided into Group A of the mothers receiving 17 - 535 rad and Group B of the mothers receiving 0 rad. Chromosome aberrations were observed in 72 (5 %) of 1,463 cells in Group A and in 19 (1 %) of 1503 cells in Group B. Most of the chromosome aberrations were stable type involving translocation, inversion, and deletion. In one person whose mother was exposed to 453 rad, structural chromosome aberrations were observed in 53 (38 %) of 141 cells. Furthermore, 11 cells had two kinds of clones. This finding may provide clues for elucidating the promotion of cloning of cells with stable type structural chromosome aberrations due to in uterus exposure to high doses of atomic radiation. (Namekawa, K.)

Changing pattern of malaria in Bissau, Guinea Bissau

DEFF Research Database (Denmark)

Rodrigues, Amabelia; Schellenberg, Joanna Armstrong; Kofoed, Poul-Erik

2008-01-01

OBJECTIVE: To describe the epidemiology of malaria in Guinea-Bissau, in view of the fact that more funds are available now for malaria control in the country. METHODS: From May 2003 to May 2004, surveillance for malaria was conducted among children less than 5 years of age at three health centres...... covering the study area of the Bandim Health Project (BHP) and at the outpatient clinic of the national hospital in Bissau. Cross-sectional surveys were conducted in the community in different malaria seasons. RESULTS: Malaria was overdiagnosed in both health centres and hospital. Sixty-four per cent...... of the children who presented at a health centre were clinically diagnosed with malaria, but only 13% of outpatient children who tested for malaria had malaria parasitaemia. Only 44% (963/2193) of children admitted to hospital with a diagnosis of malaria had parasitaemia. The proportion of positive cases...

Randomized, placebo-controlled trial of atovaquone/proguanil for the prevention of Plasmodium falciparum or Plasmodium vivax malaria among migrants to Papua, Indonesia.

Science.gov (United States)

Ling, Judith; Baird, J Kevin; Fryauff, David J; Sismadi, Priyanto; Bangs, Michael J; Lacy, Mark; Barcus, Mazie J; Gramzinski, Robert; Maguire, Jason D; Kumusumangsih, Marti; Miller, Gerri B; Jones, Trevor R; Chulay, Jeffrey D; Hoffman, Stephen L

2002-10-01

The increasing prevalence of resistance to antimalarial drugs reduces options for malaria prophylaxis. Atovaquone/proguanil (Malarone; GlaxoSmithKline) has been >95% effective in preventing Plasmodium falciparum malaria in lifelong residents of areas of holoendemicity, but data from persons without clinical immunity or who are at risk for Plasmodium vivax malaria have not been described. We conducted a randomized, double-blinded study involving 297 people from areas of nonendemicity in Indonesia who migrated to Papua (where malaria is endemic) proguanil hydrochloride; n=148) or placebo (n=149) per day for 20 weeks. Hematologic and clinical chemistry values did not change significantly. The protective efficacy of atovaquone/proguanil was 84% (95% confidence interval [CI], 44%-95%) for P. vivax malaria, 96% (95% CI, 72%-99%) for P. falciparum malaria, and 93% (95% CI, 77%-98%) overall. Atovaquone/proguanil was well tolerated, safe, and effective for the prevention of drug-resistant P. vivax and P. falciparum malaria in individuals without prior malaria exposure who migrated to Papua, Indonesia.

Malaria in pregnancy | Okpere | Nigerian Medical Journal

African Journals Online (AJOL)

Malaria remains one of the highest contributors to the precarious maternal mortality figures in sub-Saharan Africa. At least 6 million women worldwide are at risk of malaria infection in pregnancy. Malaria contributes to at least 10,000 maternal deaths and to at least 200,000 newborn deaths annually. Malaria is a contributor ...

Seeking treatment for symptomatic malaria in Papua New Guinea

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Siba Peter

2010-10-01

Full Text Available Abstract Background Malaria places a significant burden on the limited resources of many low income countries. Knowing more about why and where people seek treatment will enable policy makers to better allocate the limited resources. This study aims to better understand what influences treatment-seeking behaviour for malaria in one such low-income country context, Papua New Guinea (PNG. Methods Two culturally, linguistically and demographically different regions in PNG were selected as study sites. A cross sectional household survey was undertaken in both sites resulting in the collection of data on 928 individuals who reported suffering from malaria in the previous four weeks. A probit model was then used to identify the factors determining whether or not people sought treatment for presumptive malaria. Multinomial logit models also assisted in identifying the factors that determined where people sought treatments. Results Results in this study build upon findings from other studies. For example, while distance in PNG has previously been seen as the primary factor in influencing whether any sort of treatment will be sought, in this study cultural influences and whether it was the first, second or even third treatment for a particular episode of malaria were also important. In addition, although formal health care facilities were the most popular treatment sources, it was also found that traditional healers were a common choice. In turn, the reasons why participants chose a particular type of treatment differed according to the whether they were seeking an initial or subsequent treatments. Conclusions Simply bringing health services closer to where people live may not always result in a greater use of formal health care facilities. Policy makers in PNG need to consider within-country variation in treatment-seeking behaviour, the important role of traditional healers and also ensure that the community fully understands the potential implications

Malaria problem in Afghanistan: malaria scanning results of the Turkish medical aid group after the war.

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Oner, Yaşar Ali; Okutan, Salih Erkan; Artinyan, Elizabeth; Kocazeybek, Bekir

2005-04-01

Malaria is a parasitic infection caused by Plasmodium species and it is especially seen in tropical and subtropical areas. We aimed to evaluate the effects of the infection in Afghanistan, which is an endemic place for malaria and had severe socio-economical lost after the war. We also compared these data with the ones that were recorded before the war. Blood samples were taken from 376 malaria suspected patients who come to the health center, established by the medical group of Istanbul Medical Faculty in 2002, Afghanistan. Blood samples were screened using the OPTIMAL Rapid Malaria Test and Giemsa staining method. In 95 (25.3%) patients diagnosis was malaria. In 65 patients (17.3%) the agent of the infection was P. falciparum and in 30 patients (8%) agents were other Plasmodium species.

The role of vitamin D in malaria.

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Lương, Khanh Vinh Quốc; Nguyễn, Lan Thi Hoàng

2015-01-15

An abnormal calcium-parathyroid hormone (PTH)-vitamin D axis has been reported in patients with malaria infection. A role for vitamin D in malaria has been suggested by many studies. Genetic studies have identified numerous factors that link vitamin D to malaria, including human leukocyte antigen genes, toll-like receptors, heme oxygenase-1, angiopoietin-2, cytotoxic T lymphocyte antigen-4, nucleotide-binding oligomerization domain-like receptors, and Bcl-2. Vitamin D has also been implicated in malaria via its effects on the Bacillus Calmette-Guerin (BCG) vaccine, matrix metalloproteinases, mitogen-activated protein kinase pathways, prostaglandins, reactive oxidative species, and nitric oxide synthase. Vitamin D may be important in malaria; therefore, additional research on its role in malaria is needed.

Management of malaria in pregnancy

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Stephen J Rogerson

2017-01-01

Full Text Available Pregnant women are especially susceptible to malaria infection. Without existing immunity, severe malaria can develop requiring emergency treatment, and pregnancy loss is common. In semi-immune women, consequences of malaria for the mother include anaemia while stillbirth, premature delivery and foetal growth restriction affect the developing foetus. Preventive measures include insecticide-treated nets and (in some African settings intermittent preventive treatment. Prompt management of maternal infection is key, using parenteral artemisinins for severe malaria, and artemisinin combination treatments (ACTs in the second and third trimesters of pregnancy. ACTs may soon also be recommended as an alternative to quinine as a treatment in the first trimester of pregnancy. Monitoring the safety of antimalarials and understanding their pharmacokinetics is particularly important in pregnancy with the altered maternal physiology and the risks to the developing foetus. As increasing numbers of countries embrace malaria elimination as a goal, the special needs of the vulnerable group of pregnant women and their infants should not be overlooked.

Plasmodium vivax associated severe malaria complications among children in some malaria endemic areas of Ethiopia.

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Ketema, Tsige; Bacha, Ketema

2013-07-08

Although, Plasmodium vivax is a rare parasite in most parts of Africa, it has significant public health importance in Ethiopia. In some parts of the country, it is responsible for majority of malaria associated morbidity. Recently severe life threatening malaria syndromes, frequently associated to P. falciparum, has been reported from P. vivax mono-infections. This prompted designing of the current study to assess prevalence of severe malaria complications related to P. vivax malaria in Ethiopia. The study was conducted in two study sites, namely Kersa and Halaba Kulito districts, located in southwest and southern parts of Ethiopia, respectively. Children, aged ≤ 10 years, who visited the two health centers during the study period, were recruited to the study. Clinical and demographic characteristics such as age, sex, temperature, diarrhea, persistent vomiting, confusion, respiratory distress, hepatomegaly, splenomegaly, hemoglobinuria, and epitaxis were assessed for a total of 139 children diagnosed to have P. vivax mono-infection. Parasitological data were collected following standard procedures. Hemoglobin and glucose level were measured using portable hemocue instrument. Median age of children was 4.25 ± 2.95 years. Geometric mean parasite count and mean hemoglobin level were 4254.89 parasite/μl and 11.55 g/dl, respectively. Higher prevalence rate of malaria and severe malaria complications were observed among children enrolled in Halaba district (P infection (OR = 1.9, 95% CI, 1.08 to 3.34), while female had higher risk to anemia (OR = 1.91, 95% CI, 1.08 - 3.34). The observed number of anemic children was 43%, of which most of them were found in age range from 0-3 years. Furthermore, P. vivax malaria was a risk factor for incidence of anemia (P lower than those reported from other countries. However, incidence of severe malaria complications in one of the sites, Halaba district, where there is highest treatment failure to first line drug, could have

The incidence of malaria in travellers to South-East Asia: is local malaria transmission a useful risk indicator?

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Jänisch Thomas

2010-10-01

Full Text Available Abstract Background The presence of ongoing local malaria transmission, identified though local surveillance and reported to regional WHO offices, by S-E Asian countries, forms the basis of national and international chemoprophylaxis recommendations in western countries. The study was designed to examine whether the strategy of using malaria transmission in a local population was an accurate estimate of the malaria threat faced by travellers and a correlate of malaria in returning travellers. Methods Malaria endemicity was described from distribution and intensity in the local populations of ten S-E Asian destination countries over the period 2003-2008 from regionally reported cases to WHO offices. Travel acquired malaria was collated from malaria surveillance reports from the USA and 12 European countries over the same period. The numbers of travellers visiting the destination countries was based on immigration and tourism statistics collected on entry of tourists to the destination countries. Results In the destination countries, mean malaria rates in endemic countries ranged between 0.01 in Korea to 4:1000 population per year in Lao PDR, with higher regional rates in a number of countries. Malaria cases imported into the 13 countries declined by 47% from 140 cases in 2003 to 66 in 2008. A total of 608 cases (27.3% Plasmodium falciparum (Pf were reported over the six years, the largest number acquired in Indonesia, Thailand and Korea. Four countries had an incidence > 1 case per 100,000 traveller visits; Burma (Myanmar, Indonesia, Cambodia and Laos (range 1 to 11.8-case per 100,000 visits. The remaining six countries rates were Conclusion The intensity of malaria transmission particularly sub-national activity did not correlate with the risk of travellers acquiring malaria in the large numbers of arriving visitors. It is proposed to use a threshold incidence of > 1 case per 100,000 visits to consider targeted malaria prophylaxis

Zinc and copper levels in children with severe plasmodium falciparum malaria in an area of unstable malaria transmission in eastern Sudan

International Nuclear Information System (INIS)

Doka, Y. A.

2012-08-01

The aim of this study is to measure the levels of zinc and copper in children suffering from plasmodium falciparum malaria in an area of unstable malaria transmission in Eastern Sudan. The importance of the study emanates from the fact that this type of malaria is prevalent in a serious manner and causes many fatalities and problems. In this study the analytic statistical methodology was adopted using Atomic Absorption Spectroscopy. Subject target groups, confirmed microscopically to be infected with malaria, (severe malaria 35 samples and two control groups: 35 samples of uncomplicated malaria and 35 samples of apparently healthy). The study revealed that there is a significant increase in the level of copper for both types of malaria ( the severe and the uncomplicated) while uncomplicated malaria decreased the level of zinc significantly. The study recommended that zinc supplement could be used for the patients suffering from severe malaria. (Author)

Dynamics of malaria transmission and susceptibility to clinical malaria episodes following treatment of Plasmodium falciparum asymptomatic carriers: results of a cluster-randomized study of community-wide screening and treatment, and a parallel entomology study.

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Tiono, Alfred B; Guelbeogo, Moussa W; Sagnon, N Falé; Nébié, Issa; Sirima, Sodiomon B; Mukhopadhyay, Amitava; Hamed, Kamal

2013-11-12

In malaria-endemic countries, large proportions of individuals infected with Plasmodium falciparum are asymptomatic and constitute a reservoir of parasites for infection of newly hatched mosquitoes. Two studies were run in parallel in Burkina Faso to evaluate the impact of systematic identification and treatment of asymptomatic carriers of P. falciparum, detected by rapid diagnostic test, on disease transmission and susceptibility to clinical malaria episodes. A clinical study assessed the incidence of symptomatic malaria episodes with a parasite density >5,000/μL after three screening and treatment campaigns ~1 month apart before the rainy season; and an entomological study determined the effect of these campaigns on malaria transmission as measured by entomological inoculation rate. The intervention arm had lower prevalence of asymptomatic carriers of asexual parasites and lower prevalence of gametocyte carriers during campaigns 2 and 3 as compared to the control arm. During the entire follow-up period, out of 13,767 at-risk subjects, 2,516 subjects (intervention arm 1,332; control arm 1,184) had symptomatic malaria. Kaplan-Meier analysis of the incidence of first symptomatic malaria episode with a parasite density >5,000/μL showed that, in the total population, the two treatment arms were similar until Week 11-12 after campaign 3, corresponding with the beginning of the malaria transmission season, after which the probability of being free of symptomatic malaria was lower in the intervention arm (logrank p entomological inoculation rate was comparable in both arms, with September peaks in both indices. Community screening and targeted treatment of asymptomatic carriers of P. falciparum had no effect on the dynamics of malaria transmission, but seemed to be associated with an increase in the treated community's susceptibility to symptomatic malaria episodes after the screening campaigns had finished. These results highlight the importance of further

A method for assessing the annual dose to the most exposed individual from tritium and 14C reactor discharges to atmosphere

International Nuclear Information System (INIS)

Nair, S.

1979-10-01

A method is described for assessing the annual dose to the most exposed individual from routine releases of tritium and 14 C to the atmosphere during normal reactor operations. A detailed assessment has been made of the resulting equilibrium contamination levels in a range of foodstuffs typical of an average UK diet and of the annual doses resulting from a chronic intake of tritium and 14 C via inhalation, ingestion and, additionally, in the case of tritium, via skin absorption. Equilibrium annual doses from the global circulation of tritium and 14 C have also been calculated. Upper limits to the effective annual dose-equivalents to the most exposed individual were found to be 0.6 rem.yr -1 and 100 rem.yr -1 per Ci.yr -1 release of tritium and 14 C respectively, with the ingestion pathway contributing significantly to the overall exposure. The most exposed individual was found to be a Reference 10 year old child. The methods outlined for calculating the ingestion dose from tritium and 14 C releases hav been incorporated into the more generally applicable code FOODDOSE. The code may be used to make more realistic dose calculations to the individuals based on site-specific surveys of variables such as local meteorology, local diet and local land use for agriculture, which may lead to doses smaller than the upper limit values quoted by factors of 20 and 200 for tritium and 14 C respectively. (author)

Assessing the social vulnerability to malaria in Rwanda.

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Bizimana, Jean-Pierre; Twarabamenye, Emmanuel; Kienberger, Stefan

2015-01-07

Since 2004, malaria interventions in Rwanda have resulted in substantial decline of malaria incidence. However, this achievement is fragile as potentials for local malaria transmissions remain. The risk of getting malaria infection is partially explained by social conditions of vulnerable populations. Since vulnerability to malaria is both influenced by social and environmental factors, its complexity cannot be measured by a single value. The aim of this paper is, therefore, to apply a composite indicator approach for assessing social vulnerability to malaria in Rwanda. This assessment informs the decision-makers in targeting malaria interventions and allocating limited resources to reduce malaria burden in Rwanda. A literature review was used to conceptualize the social vulnerability to malaria and to select the appropriate vulnerability indicators. Indicators used in the index creation were classified into susceptibility and lack of resilience vulnerability domains. The main steps followed include selection of indicators and datasets, imputation of missing values, descriptive statistics, normalization and weighting of indicators, local sensitivity analysis and indicators aggregation. Correlation analysis helped to empirically evidence the association between the indicators and malaria incidence. The high values of social vulnerability to malaria are found in Gicumbi, Rusizi, Nyaruguru and Gisagara, and low values in Muhanga, Nyarugenge, Kicukiro and Nyanza. The most influential susceptibility indicators to increase malaria are population change (r = 0.729), average number of persons per bedroom (r = 0.531), number of households affected by droughts and famines (r = 0.591), and area used for irrigation (r = 0.611). The bed net ownership (r = -0.398) and poor housing wall materials (0.378) are the lack of resilience indicators that significantly correlate with malaria incidence. The developed composite index social vulnerability to malaria

Cutaneous findings in five cases of malaria

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Jignesh B Vaishnani

2011-01-01

Full Text Available Malaria is an infectious disease caused by protozoa of the genus Plasmodium. Cutaneous lesions in malaria are rarely reported and include urticaria, angioedema, petechiae, purpura, and disseminated intravascular coagulation (DIC. Here, five malaria cases associated with cutaneous lesions have been described. Out of the five cases of malaria, two were associated with urticaria and angioedema, one case was associated with urticaria, and other two were associated with reticulated blotchy erythema with petechiae. Most of the cutaneous lesions in malaria were nonspecific and reflected the different immunopathological mechanism in malarial infection.

Efficiency of a Malaria Reactive Test-and-Treat Program in Southern Zambia: A Prospective, Observational Study.

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Deutsch-Feldman, Molly; Hamapumbu, Harry; Lubinda, Jailos; Musonda, Michael; Katowa, Ben; Searle, Kelly M; Kobayashi, Tamaki; Shields, Timothy M; Stevenson, Jennifer C; Thuma, Philip E; Moss, William J; For The Southern Africa International Centers Of Excellence For Malaria Research

2018-05-01

To improve malaria surveillance and achieve elimination, the Zambian National Malaria Elimination Program implemented a reactive test-and-treat program in Southern Province in 2013 in which individuals with rapid diagnostic test (RDT)-confirmed malaria are followed-up at their home within 1 week of diagnosis. Individuals present at the index case household and those residing within 140 m of the index case are tested with an RDT and treated with artemether-lumefantrine if positive. This study evaluated the efficiency of this reactive test-and-treat strategy by characterizing infected individuals missed by the RDT and the current screening radius. The radius was expanded to 250 m, and a quantitative polymerase chain reaction (qPCR) test was performed on dried blood spot specimens. From January 2015 through March 2016, 145 index cases were identified at health centers and health posts. A total of 3,333 individuals residing in 525 households were screened. Excluding index cases, the parasite prevalence was 1.1% by RDT (33 positives of 3,016 participants) and 2.4% by qPCR (73 positives of 3,016 participants). Of the qPCR-positive cases, 62% of 73 individuals tested negative by RDT. Approximately half of the infected individuals resided within the index case household (58% of RDT-positive individuals and 48% of qPCR-positive individuals). The low sensitivity of the RDT and the high proportion of secondary cases within the index case household decreased the efficiency of this reactive test-and-treat strategy. Reactive focal drug administration in index case households would be a more efficient approach to treating infected individuals associated with a symptomatic case.

Economic cost analysis of malaria case management at the household level during the malaria elimination phase in The People's Republic of China.

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Xia, Shang; Ma, Jin-Xiang; Wang, Duo-Quan; Li, Shi-Zhu; Rollinson, David; Zhou, Shui-Sen; Zhou, Xiao-Nong

2016-06-03

In China, malaria has been posing a significant economic burden on households. To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in China. A number of study sites (eight counties in five provinces) were selected from the malaria endemic area in China, representing the different levels of malaria incidence, risk classification, economic development. A number of households with malaria cases (n = 923) were surveyed during the May to December in 2012 to collect information on malaria economic burden. Descriptive statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender, age group, occupation and malaria type. The malaria economic costs were evaluated by direct and indirect costs. Comparisons were carried out by using the chi-square test (or Z-test) and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients, hospitalized/out patients, and treatment hospitals. The average cost of malaria per case was 1 691.23 CNY (direct cost was 735.41 CNY and indirect cost was 955.82 CNY), which accounted for 11.1 % of a household's total income. The average costs per case for local and imported malaria were 1 087.58 CNY and 4271.93 CNY, respectively. The average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above (3 975.43 CNY) was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital (938.80 CNY). This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect costs. There is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria, especially of imported infections, in order to eliminate the disease in China.

Ownership and Use of Insecticide-Treated Nets among People Living in Malaria Endemic Areas of Eastern Myanmar.

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Aung, Tin; Wei, Chongyi; McFarland, Willi; Aung, Ye Kyaw; Khin, Hnin Su Su

2016-01-01

Myanmar has the highest burden of malaria in the Greater Mekong. However, there is limited information on ownership and use of insecticide-treated nets (ITNs) in areas of Myanmar most severely affected by malaria. We describe ownership and use of ITNs among people in the malaria-endemic eastern parts of Myanmar and factors associated with ITN use. A cross-sectional household survey using a multi-stage cluster design was conducted in malaria-endemic townships in eastern Myanmar during the high malaria season of August to September, 2014. An effective ITN was defined as 1) a long-lasting insecticide-treated net obtained within the past three years, or 2) any net treated with insecticide within the past year. In 4,679 households, the average number of ITNs per household was higher in rural compared to urban areas (0.6 vs. 0.4, p Myanmar in comparison to the goal of one for every two household members. Use of ITNs was low even when present. Findings are of concern given the study areas were part of enhanced efforts to reduce artemisinin-resistant malaria. Nonetheless, groups vulnerable to malaria such as individuals in rural settings, lower socio-economic households, and workers in high mosquito exposure jobs, had higher rates of ITN ownership. Malaria knowledge was linked to effective ITN use suggesting that distribution campaigns should be complemented by behavior change communications.

Does radical cure of asymptomatic Plasmodium falciparum place adults in endemic areas at increased risk of recurrent symptomatic malaria?

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Owusu-Agyei, Seth; Binka, Fred; Koram, Kwadwo; Anto, Francis; Adjuik, Martin; Nkrumah, Francis; Smith, Tom

2002-07-01

A cohort of 197 adults in Kassena-Nankana District (northern Ghana) was radically cured of malaria parasites to study subsequent incidence of malaria infection. During the following 20 weeks of the malaria transmission season, 49% experienced clinical attacks associated with Plasmodium falciparum parasitaemia. In a group of 202 adults identically followed-up 1 year later without being treated, only 38% experienced such episodes (log-rank test for equality of survivor functions, P=0.035). Clinical attacks in radically cured individuals presented with lower parasite densities but more symptoms. Randomized studies are needed to test the hypothesis that radical cure of P. falciparum enhances the risk and severity of subsequent clinical malaria attacks.

Association between serum transferrin receptor levels and malaria ...

African Journals Online (AJOL)

user

... and malaria is common in sub-Saharan Africa, and is a complex phenomenon. ... iron status and malaria incidence among children in a high malaria ... seasonally as cash crops. ... Children were followed for presence of malaria parasites by.

Malaria - sick air on the march

International Nuclear Information System (INIS)

Aunan, Kristin

1999-01-01

The article surveys the expansion of the malaria risk zones with increasing temperatures, change in climate and habitat alterations. Factors such as the living conditions for various malaria parasites, climatic changes, immunity and drug resistance are studied. It is evident that the greenhouse effects contribute to the expanding malaria risk zones

[Vaccinations and malaria prophylaxis for international travelers].

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Alberer, Martin; Löscher, Thomas

2015-05-01

The prevention of infectious diseases by vaccination and by counselling about malaria prophylaxis is a central aspect of travel medicine. Besides mandatory vaccinations required for entry to certain countries various vaccinations may be indicated depending on destination and type of travel as well as on individual risks of the traveler. In addition, pre-travel counselling should always include a check-up of standard vaccinations. Protection against mosquito bites is the basis of malaria prophylaxis. The addition of chemoprophylaxis is warranted in high risk areas. When regular chemoprophylaxis is not applied it is recommended to carry an appropriate antimalarial drug which can be used for emergency stand-by treatment in case of unexplained fever and when medical attention is not available within 24 hours. Travelers should realize that self-treatment is a first-aid measure and that they should still seek medical advice as soon as possible. © Georg Thieme Verlag KG Stuttgart · New York.

A review of concurrent infections of malaria and dengue in Asia

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Aruchana A/P Selvaretnam

2016-07-01

Full Text Available Concurrent infections of malaria and dengue are when both of these mosquito-borne diseases occur simultaneously in an individual. In this review, reported cases with these co-infections in Asia are discussed. The focus is on the overlapping clinical presentations and the difficulties encountered in differential diagnosis. Also, cases reported in some special conditions, viz., pregnancy, foetal infections, and co-infections with one or more other infectious agents are highlighted. Due to similar clinical presentations of malaria and dengue, these co-infections may give rise to an incorrect diagnosis. Moreover, the treatment regimens for these co-infections are not the same as those for mono-infections. Hence, a delay in implementing the appropriate treatment regimen for these concurrent infections due to poor diagnosis can be fatal. The present review is intended to increase awareness about the clinical significance and the importance of these co-infections among clinicians, public health workers and health authorities in the Asian region. Though malaria-dengue concurrent infections are seldom reported from the Asian region, it is probably increasing particularly in the countries known to be endemic for both of the above diseases. A compulsory reporting of the incidences of malaria-dengue concurrent infections is recommended.

Gold mining areas in Suriname: reservoirs of malaria resistance?

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Adhin MR

2014-05-01

Full Text Available Malti R Adhin,1 Mergiory Labadie-Bracho,2 Stephen Vreden31Faculty of Medical Sciences, Department of Biochemistry, Anton de Kom Universiteit van Suriname, 2Prof Dr Paul C Flu Institute for Biomedical Sciences, 3Academic Hospital Paramaribo, Paramaribo, SurinameBackground: At present, malaria cases in Suriname occur predominantly in migrants and people living and/or working in areas with gold mining operations. A molecular survey was performed in Plasmodium falciparum isolates originating from persons from gold mining areas to assess the extent and role of mining areas as reservoirs of malaria resistance in Suriname.Methods: The status of 14 putative resistance-associated single nucleotide polymorphisms in the pfdhfr, pfcrt, pfmdr1, and pfATP6 genes was assessed for 28 samples from gold miners diagnosed with P. falciparum malaria using polymerase chain reaction amplification and restriction fragment length polymorphism analysis, and the results were compared with earlier data from nonmining villagers.Results: Isolates from miners showed a high degree of homogeneity, with a fixed pfdhfr Ile51/Asn108, pfmdr1 Phe184/Asp1042/Tyr1246, and pfcrt Thr76 mutant genotype, while an exclusively wild-type genotype was observed for pfmdr1 Asn86 and pfdhfr Ala16, Cys59, and Ile164, and for the pfATP6 positions Leu263/Ala623/Ser769. Small variations were observed for pfmdr1 S1034C. No statistically significant difference could be detected in allele frequencies between mining and nonmining villagers.Conclusion: Despite the increased risk of malaria infection in individuals working/living in gold mining areas, we did not detect an increase in mutation frequency at the 14 analyzed single nucleotide polymorphisms. Therefore, mining areas in Suriname cannot yet be considered as reservoirs for malaria resistance.Keywords: Plasmodium falciparum, gold mining, mutation frequency, Suriname

Development of replication-deficient adenovirus malaria vaccines.

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