The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Jinyong Zhang - One of the best experts on this subject based on the ideXlab platform.
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outbreak of Trypanosomiasis in net cage cultured barramundi lates calcarifer perciformes latidae associated with trypanosoma epinepheli kinetoplastida in south china sea
Aquaculture, 2019Co-Authors: Dan Luo, X H Liu, Hiroshi Sato, Jinyong ZhangAbstract:Abstract The barramundi or Asian Sea bass (Lates calcarifer) is of high economic importance for aquaculture worldwide. The present work report a trypanosomiosis of net cage reared barramundi in South China Sea and identified Trypanosoma epinepheli to be the causative agent, which expand the host range of this blood flagellate. This epizootic trypanosomiosis was of distinctly seasonal pattern which occurred from middle-to-late March to middle-to-late May, when water temperature ranged from 21 to 28°C and salinity from 30-33ppt.The infected fish showed typical clinical symptoms of fish trypanosomiosis, including loss of appetite, lethargy, slight emaciation, slightly darken body, swimming lonely and restlessly at the water surface. Mild anemia in gills and remarkable splenomegaly were observed after necropsy. Histopathological investigations showed distinct pathological changes in gill, brain, liver, spleen and kidney, almost consistent with the previous report. This study is the first report of Trypanosomiasis in this increasingly important mariculture fish in China.
Paul Mccord - One of the best experts on this subject based on the ideXlab platform.
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Population vulnerability and disability in Kenya's tsetse fly habitats.
PLOS Neglected Tropical Diseases, 2011Co-Authors: Sue C. Grady, Joseph P Messina, Paul MccordAbstract:Background Human African Trypanosomiasis (HAT), also referred to as sleeping sickness, and African Animal Trypanosomaisis (AAT), known as nagana, are highly prevalent parasitic vector-borne diseases in sub-Saharan Africa. Humans acquire Trypanosomiasis following the bite of a tsetse fly infected with the protozoa Trypanosoma brucei (T.b.) spp. –i.e., T.b. gambiense in West and Central Africa and T.b. rhodesiense in East and Southern Africa. Over the last decade HAT diagnostic capacity to estimate HAT prevalence has improved in active case-finding areas but enhanced passive surveillance programs are still lacking in much of rural sub-Saharan Africa.
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Population vulnerability and disability in Kenya's tsetse fly habitats.
PLoS neglected tropical diseases, 2011Co-Authors: Sue C. Grady, Joseph P Messina, Paul MccordAbstract:Human African Trypanosomiasis (HAT), also referred to as sleeping sickness, and African Animal Trypanosomaisis (AAT), known as nagana, are highly prevalent parasitic vector-borne diseases in sub-Saharan Africa. Humans acquire Trypanosomiasis following the bite of a tsetse fly infected with the protozoa Trypanosoma brucei (T.b.) spp. -i.e., T.b. gambiense in West and Central Africa and T.b. rhodesiense in East and Southern Africa. Over the last decade HAT diagnostic capacity to estimate HAT prevalence has improved in active case-finding areas but enhanced passive surveillance programs are still lacking in much of rural sub-Saharan Africa. This retrospective-cross-sectional study examined the use of national census data (1999) to estimate population vulnerability and disability in Kenya's 7 tsetse belts to assess the potential of HAT-acquired infection in those areas. A multilevel study design estimated the likelihood of disability in individuals, nested within households, nested within tsetse fly habitats of varying levels of poverty. Residents and recent migrants of working age were studied. Tsetse fly's impact on disability was conceptualised via two exposure pathways: directly from the bite of a pathogenic tsetse fly resulting in HAT infection or indirectly, as the potential for AAT takes land out of agricultural production and diseased livestock leads to livestock morbidity and mortality, contributing to nutritional deficiencies and poverty. Tsetse belts that were significantly associated with increased disability prevalence were identified and the direct and indirect exposure pathways were evaluated. Incorporating reports on disability from the national census is a promising surveillance tool that may enhance future HAT surveillance programs in sub-Saharan Africa. The combined burdens of HAT and AAT and the opportunity costs of agricultural production in AAT areas are likely contributors to disability within tsetse-infested areas. Future research will assess changes in the spatial relationships between high tsetse infestation and human disability following the release of the Kenya 2009 census at the local level.
Harry Noyes - One of the best experts on this subject based on the ideXlab platform.
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apol1 renal risk variants have contrasting resistance and susceptibility associations with african Trypanosomiasis
eLife, 2017Co-Authors: Anneli Cooper, Sophie Ravel, Hamidou Ilboudo, Pius V Alibu, John Enyaru, William Weir, Harry NoyesAbstract:Reduced susceptibility to infectious disease can increase the frequency of otherwise deleterious alleles. In populations of African ancestry, two apolipoprotein-L1 (APOL1) variants with a recessive kidney disease risk, named G1 and G2, occur at high frequency. APOL1 is a trypanolytic protein that confers innate resistance to most African trypanosomes, but not Trypanosoma brucei rhodesiense or T.b. gambiense, which cause human African Trypanosomiasis. In this case-control study, we test the prevailing hypothesis that these APOL1 variants reduce Trypanosomiasis susceptibility, resulting in their positive selection in sub-Saharan Africa. We demonstrate a five-fold dominant protective association for G2 against T.b. rhodesiense infection. Furthermore, we report unpredicted strong opposing associations with T.b. gambiense disease outcome. G2 associates with faster progression of T.b. gambiense Trypanosomiasis, while G1 associates with asymptomatic carriage and undetectable parasitemia. These results implicate both forms of human African Trypanosomiasis in the selection and persistence of otherwise detrimental APOL1 kidney disease variants.
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Multiorgan dysfunction caused by travel-associated African Trypanosomiasis.
Emerging infectious diseases, 2012Co-Authors: Lucy E. Cottle, Harry Noyes, Joanna R. Peters, Alison Hall, J. Wendi Bailey, Jane E. Rimington, Nicholas J. Beeching, S. Bertel Squire, Mike B.j. BeadsworthAbstract:We describe a case of multiorgan dysfunction secondary to Trypanosoma brucei rhodesiense infection acquired on safari in Zambia. This case was one of several recently reported to ProMED-mail in persons who had traveled to this region. Trypanosomiasis remains rare in travelers but should be considered in febrile patients who have returned from Trypanosomiasis-endemic areas of Africa.
Sue C. Grady - One of the best experts on this subject based on the ideXlab platform.
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Population vulnerability and disability in Kenya's tsetse fly habitats.
PLOS Neglected Tropical Diseases, 2011Co-Authors: Sue C. Grady, Joseph P Messina, Paul MccordAbstract:Background Human African Trypanosomiasis (HAT), also referred to as sleeping sickness, and African Animal Trypanosomaisis (AAT), known as nagana, are highly prevalent parasitic vector-borne diseases in sub-Saharan Africa. Humans acquire Trypanosomiasis following the bite of a tsetse fly infected with the protozoa Trypanosoma brucei (T.b.) spp. –i.e., T.b. gambiense in West and Central Africa and T.b. rhodesiense in East and Southern Africa. Over the last decade HAT diagnostic capacity to estimate HAT prevalence has improved in active case-finding areas but enhanced passive surveillance programs are still lacking in much of rural sub-Saharan Africa.
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Population vulnerability and disability in Kenya's tsetse fly habitats.
PLoS neglected tropical diseases, 2011Co-Authors: Sue C. Grady, Joseph P Messina, Paul MccordAbstract:Human African Trypanosomiasis (HAT), also referred to as sleeping sickness, and African Animal Trypanosomaisis (AAT), known as nagana, are highly prevalent parasitic vector-borne diseases in sub-Saharan Africa. Humans acquire Trypanosomiasis following the bite of a tsetse fly infected with the protozoa Trypanosoma brucei (T.b.) spp. -i.e., T.b. gambiense in West and Central Africa and T.b. rhodesiense in East and Southern Africa. Over the last decade HAT diagnostic capacity to estimate HAT prevalence has improved in active case-finding areas but enhanced passive surveillance programs are still lacking in much of rural sub-Saharan Africa. This retrospective-cross-sectional study examined the use of national census data (1999) to estimate population vulnerability and disability in Kenya's 7 tsetse belts to assess the potential of HAT-acquired infection in those areas. A multilevel study design estimated the likelihood of disability in individuals, nested within households, nested within tsetse fly habitats of varying levels of poverty. Residents and recent migrants of working age were studied. Tsetse fly's impact on disability was conceptualised via two exposure pathways: directly from the bite of a pathogenic tsetse fly resulting in HAT infection or indirectly, as the potential for AAT takes land out of agricultural production and diseased livestock leads to livestock morbidity and mortality, contributing to nutritional deficiencies and poverty. Tsetse belts that were significantly associated with increased disability prevalence were identified and the direct and indirect exposure pathways were evaluated. Incorporating reports on disability from the national census is a promising surveillance tool that may enhance future HAT surveillance programs in sub-Saharan Africa. The combined burdens of HAT and AAT and the opportunity costs of agricultural production in AAT areas are likely contributors to disability within tsetse-infested areas. Future research will assess changes in the spatial relationships between high tsetse infestation and human disability following the release of the Kenya 2009 census at the local level.
Jacques Pepin - One of the best experts on this subject based on the ideXlab platform.
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Iatrogenic transmission of human T cell lymphotropic virus type 1 and hepatitis C virus through parenteral treatment and chemoprophylaxis of sleeping sickness in colonial Equatorial Africa.
Clinical Infectious Diseases, 2010Co-Authors: Jacques Pepin, Annie-claude Labbé, Fleurie Mamadou-yaya, Pascal M'belesso, Sylvestre Mbadingaï, Sylvie Deslandes, Marie-claude Locas, Eric FrostAbstract:BACKGROUND: The simultaneous emergence of human immunodeficiency virus (HIV)-1 group M and HIV-2 into human populations, circa 1921-1940, is attributed to urbanization and changes in sexual behavior. We hypothesized that the initial dissemination of HIV-1, before sexual transmission predominated, was facilitated by the administration, via reusable syringes and needles, of parenteral drugs against tropical diseases. As proxies for highly lethal HIV-1, we investigated risk factors for hepatitis C virus (HCV) and human T cell lymphotropic virus 1 (HTLV-1) infections, blood-borne viruses compatible with prolonged survival, in an area known in 1936-1950 as the most virulent focus of African Trypanosomiasis. METHODS: Cross-sectional survey of individuals 55 years and older in Mbimou land and Nola, Central African Republic. Dried blood spots were used for HCV and HTLV-1 serologic testing and nucleic acid detection. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were measured by logistic regression. RESULTS: The only risk factor for HCV genotype 4 infection was treatment of Trypanosomiasis before 1951 (OR, 3.13; 95% CI, 1.38-7.09). HTLV-1 infection was associated with having received 2 injections of pentamidine for Trypanosomiasis chemoprophylaxis (adjusted OR, 2.03; 95% CI, 1.01-4.06) and with transfusions (adjusted OR, 2.82; 95% CI, 1.04-7.67). From historical data, we predicted that 59% of Mbimous 65 years and older would report treatment for Trypanosomiasis before 1951; only 11% did so. CONCLUSIONS: Treatment of Trypanosomiasis before 1951 may have caused iatrogenic HCV transmission. Population-wide half-yearly intramuscular pentamidine for Trypanosomiasis chemoprophylaxis in 1947-1953 may have caused iatrogenic HTLV-1 transmission. These and other interventions against tropical diseases could have iatrogenically transmitted SIV(cpz), jump-starting the HIV-1 epidemic. The excess mortality among patients with Trypanosomiasis treated before 1951 supports this hypothesis.
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the epidemiology and control of human african Trypanosomiasis
Advances in Parasitology, 2001Co-Authors: Jacques Pepin, Honore MedaAbstract:Abstract Human African Trypanosomiasis is caused by Trypanosoma brucei gambiense in West and Central Africa, and by Trypanosoma brucei rhodesiense in East and southern Africa. In recent years there has been a dramatic resurgence of Gambian trypabosomiasis in Central Africa, especially in the Democratic Republic of Congo, Angola and Sudan. The disease is quiescent in most of West Africa, as is Rhodesian Trypanosomiasis the other side of the continent. The epidemiology of Gambian Trypanosomiasis is reviewed in detail. The long duration of infection in human hosts with cycles of intermittent parasitaemia, the vector's feeding habits and the intensity of human-fly contact are the major determinants of the dynamics of transmission of this parasite. The development of immunity may lead to a reduction in the fraction of the population that is susceptible to infection and the burning out of epidemics after 20 to 30 years. So far, the acquired immune deficiency syndrom pandemic has had no impact on the epidemiology of Gambian Trypanosomiasis. A brief review of the epidemiology of Rhodesian Trypanosomiasis highlights the differences from Gambian Trypanosomiasis that, to some extent, explain its lower propensity to cause epidemics: it is a more aggressive disease that rapidly kills its human host, and its transmission involves mostly domestic and game animals, humans being in most circumstances an accidental host. The various methods and strategies for the surveillance and control of both diseases are reviewed.
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epidemiological evidence for immunity following trypanosoma brucei gambiense sleeping sickness
Transactions of The Royal Society of Tropical Medicine and Hygiene, 1995Co-Authors: Nzambi Khonde, Jacques Pepin, Theophile Niyonsenga, F Milord, Philippe De WalsAbstract:In order to investigate whether protective immunity appears after Trypanosoma brucei gambiense sleeping sickness, we undertook a retrospective cohort study of 3 remote villages in central Zaire (total population 1431), in which 38% of all adults had a past history of human African Trypanosomiasis. Among adults previously diagnosed with Trypanosomiasis and treated, the risk of a second episode of Trypanosomiasis during the 10 years period of observation was only 15% (with a 24 months refractory period) and 30% (without a refractory period) of the risk of a first episode in adults never previously diagnosed. We could not demonstrate a similar difference among children, to some extent because only a few of them were diagnosed for a first time with Trypanosomiasis. Our findings suggest that very significant immunity appears after Gambian sleeping sickness, and that developing a vaccine against this subspecies of trypanosomes is biologically plausible.
