The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Henry W. Murray - One of the best experts on this subject based on the ideXlab platform.
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Cutaneous Leishmaniasis: Current Treatment Practices in the USA for Returning Travelers
Current Treatment Options in Infectious Diseases, 2015Co-Authors: Daniel P. Eiras, Laura A. Kirkman, Henry W. MurrayAbstract:Leishmaniasis, a Protozoal Infection transmitted by sandfly bite, produces a clinical spectrum of disease ranging from asymptomatic Infection to ulcerative skin and mucosal lesions to visceral involvement. Leishmaniasis is endemic in regions of Africa, the Middle East, south Asia, southern Europe, northern South America, and Central America. There has been an increase in imported leishmaniasis into developed, non-endemic countries due to increasing global travel. While pentavalent antimonials have been the mainstay of antileishmanial treatment for decades, newer therapeutic options have become available for all forms of Infection, including liposomal amphotericin B, miltefosine, fluconazole, and ketoconazole. For the returning traveler with cutaneous leishmaniasis in the USA, treatment approaches are determined based on infecting species, initial presentation, extent and progression of disease, the advantages and drawbacks of available parenteral and oral drugs, and clinician-consultant experience.
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Progress in the treatment of a neglected infectious disease: visceral leishmaniasis.
Expert review of anti-infective therapy, 2004Co-Authors: Henry W. MurrayAbstract:Visceral leishmaniasis (kala-azar) is a disseminated intracellular Protozoal Infection. Most cases (90%) occur in the rural regions of five countries: India, Sudan, Nepal, Bangladesh and Brazil. As...
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clinical and experimental advances in treatment of visceral leishmaniasis
Antimicrobial Agents and Chemotherapy, 2001Co-Authors: Henry W. MurrayAbstract:Visceral leishmaniaisis (kala-azar) is a disseminated Protozoal Infection, transmitted by sandfly bite, in which macrophages of the liver, spleen, and bone marrow are preferentially parasitized and support intracellular replication. Most human Infections caused by visceralizing strains of Leishmania are probably subclinical (13, 101, 139), attesting to innate resistance or, more likely, to T (Th1)-cell-dependent immune responses which induce acquired resistance (33, 39, 79, 101, 102). While treatment is not given for subclinical Infection, remote recrudescence still remains a possibility, especially if the host becomes T-cell deficient (62, 66, 76, 123). In contrast, if the initial Th1-cell-associated immune response fails to develop or its effector mechanisms are disabled or not properly maintained (122, 123), recently acquired (or reactivated) kala-azar evolves to full expression as a subacute or chronic illness for which treatment is required.
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Trial of oral miltefosine for visceral leishmaniasis
The Lancet, 1998Co-Authors: Shyam Sundar, Frank Rosenkaimer, Manoj K. Makharia, Ashish K Goyal, Ashim K Mandal, Andreas Voss, Peter Hilgard, Henry W. MurrayAbstract:Summary Background There is no effective oral treatment for visceral leishmaniasis (kala-azar), a disseminated intracellular Protozoal Infection that occurs worldwide. Miltefosine, an alkyl phospholipid developed as an oral antineoplastic agent, is active against visceral Infection in animal models. We tested safety, tolerance, and efficacy of miltefosine in kalaazar. Methods Oral doses of miltefosine were given to six groups of five Indian men for 28 days: 50 mg every second day (group 1), 100 mg every second day (group 2), 100 mg/day (group 3), 150 mg/day (group 4), 200 mg/day (group 5), and 250 mg/day (group 6). Assessment for apparent cure—taken as an afebrile state with decreased spleen size and a splenic-aspirate parasite-density score of 0-was done on days 14 and 28. Definitive cure at 8 months required a parasite-free bone-marrow aspirate and no clinical evidence of relapse. Findings 21 of 30 patients were apparently cured on day 14. Transient episodes of vomiting and diarrhoea, were common during weeks 1–2 and were seen in 22 patients. Four other patients in groups 5 and 6 had miltefosine withdrawn after 7–10 days because of vomiting. One patient in group 6 developed renal insufficiency and severe diarrhoea and died on day 21. On day 28, all 29 remaining patients were apparently cured. By 8 months, seven of ten patients in groups 1 and 2 had relapsed; however, 18 of 19 patients treated daily (groups 3–6) appeared to be cured. Among the 21 definitive cures were the four patients treated for 10 days or less and 12 for whom previous therapy with pentavalent antimony had failed. Interpretation Treatment with miltefosine at 100–150 mg/day for 4 weeks has promise as an effective oral treatment of visceral leishmaniasis including antimonyresistant Infection.
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short course low dose amphotericin b lipid complex therapy for visceral leishmaniasis unresponsive to antimony
Annals of Internal Medicine, 1997Co-Authors: Shyam Sundar, N Agrawal, Prabhat R Sinha, Gary S Horwith, Henry W. MurrayAbstract:Background: Visceral leishmaniasis (kala-azar) is a world-wide, disseminated intracellular Protozoal Infection for which prolonged, conventional therapy with pentavalent antimony has become increas...
J. M. Pemberton - One of the best experts on this subject based on the ideXlab platform.
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epidemiology of parasitic protozoan Infections in soay sheep ovis aries l on st kilda
Parasitology, 2007Co-Authors: B. H. Craig, J. G. Pilkington, L. E. B. Kruuk, J. M. PembertonAbstract:The feral Soay sheep (Ovis aries L.) population on Hirta, St Kilda, is host to a diverse component parasite community, but previous parasitological studies of the population have only focussed on the metazoan species. This paper reports the first epidemiological study of the protozoan species comprising Cryptosporidium parvum, Giardia duodenalis and 11 species of Eimeria in Soay sheep across 3 years of varying host population density. Prevalence and intensity of almost all species of protozoa significantly decreased with host age, with the exception of E. granulosa, which increased in prevalence with host age. The prevalence of C. parvum appeared to vary positively with host population density but that of G. duodenalis did not vary significantly with density. Most species of Eimeria showed a distinct lag in Infection level following the host population crash of 2002, taking up to 2 years to decrease. Mixed Eimeria species intensity and diversity were highest in 2002, a year of low host density. Parasite diversity decreased with host age and was higher in males. There were 5 positive pair-wise associations between protozoa species in terms of prevalence. The results of this study highlight the potential for Protozoal Infection to shape the evolution of parasite resistance in wild host populations harbouring diverse parasite species.
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Epidemiology of parasitic protozoan Infections in Soay sheep (Ovis ariesL.) on St Kilda
Parasitology, 2006Co-Authors: B. H. Craig, J. G. Pilkington, L. E. B. Kruuk, J. M. PembertonAbstract:The feral Soay sheep (Ovis ariesL.) population on Hirta, St Kilda, is host to a diverse component parasite community, but previous parasitological studies of the population have only focussed on the metazoan species. This paper reports the first epidemiological study of the protozoan species comprisingCryptosporidium parvum,Giardia duodenalisand 11 species ofEimeriain Soay sheep across 3 years of varying host population density. Prevalence and intensity of almost all species of protozoa significantly decreased with host age, with the exception ofE. granulosa, which increased in prevalence with host age. The prevalence ofC. parvumappeared to vary positively with host population density but that ofG. duodenalisdid not vary significantly with density. Most species ofEimeriashowed a distinct lag in Infection level following the host population crash of 2002, taking up to 2 years to decrease. MixedEimeriaspecies intensity and diversity were highest in 2002, a year of low host density. Parasite diversity decreased with host age and was higher in males. There were 5 positive pair-wise associations between protozoa species in terms of prevalence. The results of this study highlight the potential for Protozoal Infection to shape the evolution of parasite resistance in wild host populations harbouring diverse parasite species.
B. H. Craig - One of the best experts on this subject based on the ideXlab platform.
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epidemiology of parasitic protozoan Infections in soay sheep ovis aries l on st kilda
Parasitology, 2007Co-Authors: B. H. Craig, J. G. Pilkington, L. E. B. Kruuk, J. M. PembertonAbstract:The feral Soay sheep (Ovis aries L.) population on Hirta, St Kilda, is host to a diverse component parasite community, but previous parasitological studies of the population have only focussed on the metazoan species. This paper reports the first epidemiological study of the protozoan species comprising Cryptosporidium parvum, Giardia duodenalis and 11 species of Eimeria in Soay sheep across 3 years of varying host population density. Prevalence and intensity of almost all species of protozoa significantly decreased with host age, with the exception of E. granulosa, which increased in prevalence with host age. The prevalence of C. parvum appeared to vary positively with host population density but that of G. duodenalis did not vary significantly with density. Most species of Eimeria showed a distinct lag in Infection level following the host population crash of 2002, taking up to 2 years to decrease. Mixed Eimeria species intensity and diversity were highest in 2002, a year of low host density. Parasite diversity decreased with host age and was higher in males. There were 5 positive pair-wise associations between protozoa species in terms of prevalence. The results of this study highlight the potential for Protozoal Infection to shape the evolution of parasite resistance in wild host populations harbouring diverse parasite species.
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Epidemiology of parasitic protozoan Infections in Soay sheep (Ovis ariesL.) on St Kilda
Parasitology, 2006Co-Authors: B. H. Craig, J. G. Pilkington, L. E. B. Kruuk, J. M. PembertonAbstract:The feral Soay sheep (Ovis ariesL.) population on Hirta, St Kilda, is host to a diverse component parasite community, but previous parasitological studies of the population have only focussed on the metazoan species. This paper reports the first epidemiological study of the protozoan species comprisingCryptosporidium parvum,Giardia duodenalisand 11 species ofEimeriain Soay sheep across 3 years of varying host population density. Prevalence and intensity of almost all species of protozoa significantly decreased with host age, with the exception ofE. granulosa, which increased in prevalence with host age. The prevalence ofC. parvumappeared to vary positively with host population density but that ofG. duodenalisdid not vary significantly with density. Most species ofEimeriashowed a distinct lag in Infection level following the host population crash of 2002, taking up to 2 years to decrease. MixedEimeriaspecies intensity and diversity were highest in 2002, a year of low host density. Parasite diversity decreased with host age and was higher in males. There were 5 positive pair-wise associations between protozoa species in terms of prevalence. The results of this study highlight the potential for Protozoal Infection to shape the evolution of parasite resistance in wild host populations harbouring diverse parasite species.
Matthew C Freeman - One of the best experts on this subject based on the ideXlab platform.
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associations between soil transmitted helminthiasis and viral bacterial and Protozoal enteroInfections a cross sectional study in rural laos
Parasites & Vectors, 2019Co-Authors: Anna N Chard, Kelly K Baker, Kevin Tsai, Karen Levy, Jeticia R Sistrunk, Howard H Chang, Matthew C FreemanAbstract:Humans are susceptible to over 1400 pathogens. Co-Infection by multiple pathogens is common, and can result in a range of neutral, facilitative, or antagonistic interactions within the host. Soil-transmitted helminths (STH) are powerful immunomodulators, but evidence of the effect of STH Infection on the direction and magnitude of concurrent enteric microparasite Infections is mixed. We collected fecal samples from 891 randomly selected children and adults in rural Laos. Samples were analyzed for 5 STH species, 6 viruses, 9 bacteria, and 5 protozoa using a quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. We utilized logistic regression, controlling for demographics and household water, sanitation, and hygiene access, to examine the effect of STH Infection on concurrent viral, bacterial, and Protozoal Infection. We found that STH Infection was associated with lower odds of concurrent viral Infection [odds ratio (OR): 0.48, 95% confidence interval (CI): 0.28–0.83], but higher odds of concurrent bacterial Infections (OR: 1.81, 95% CI: 1.06–3.07) and concurrent Protozoal Infections (OR: 1.50, 95% CI: 0.95–2.37). Trends were consistent across STH species. The impact of STH on odds of concurrent microparasite co-Infection may differ by microparasite taxa, whereby STH Infection was negatively associated with viral Infections but positively associated with bacterial and Protozoal Infections. Results suggest that efforts to reduce STH through preventive chemotherapy could have a spillover effect on microparasite Infections, though the extent of this impact requires additional study. The associations between STH and concurrent microparasite Infection may reflect a reverse effect due to the cross-sectional study design. Additional research is needed to elucidate the exact mechanism of the immunomodulatory effects of STH on concurrent enteric microparasite Infection.
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Associations between soil-transmitted helminthiasis and viral, bacterial, and Protozoal enteroInfections: a cross-sectional study in rural Laos
BMC, 2019Co-Authors: Anna N Chard, Kelly K Baker, Kevin Tsai, Karen Levy, Jeticia R Sistrunk, Howard H Chang, Matthew C FreemanAbstract:Abstract Background Humans are susceptible to over 1400 pathogens. Co-Infection by multiple pathogens is common, and can result in a range of neutral, facilitative, or antagonistic interactions within the host. Soil-transmitted helminths (STH) are powerful immunomodulators, but evidence of the effect of STH Infection on the direction and magnitude of concurrent enteric microparasite Infections is mixed. Methods We collected fecal samples from 891 randomly selected children and adults in rural Laos. Samples were analyzed for 5 STH species, 6 viruses, 9 bacteria, and 5 protozoa using a quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. We utilized logistic regression, controlling for demographics and household water, sanitation, and hygiene access, to examine the effect of STH Infection on concurrent viral, bacterial, and Protozoal Infection. Results We found that STH Infection was associated with lower odds of concurrent viral Infection [odds ratio (OR): 0.48, 95% confidence interval (CI): 0.28–0.83], but higher odds of concurrent bacterial Infections (OR: 1.81, 95% CI: 1.06–3.07) and concurrent Protozoal Infections (OR: 1.50, 95% CI: 0.95–2.37). Trends were consistent across STH species. Conclusions The impact of STH on odds of concurrent microparasite co-Infection may differ by microparasite taxa, whereby STH Infection was negatively associated with viral Infections but positively associated with bacterial and Protozoal Infections. Results suggest that efforts to reduce STH through preventive chemotherapy could have a spillover effect on microparasite Infections, though the extent of this impact requires additional study. The associations between STH and concurrent microparasite Infection may reflect a reverse effect due to the cross-sectional study design. Additional research is needed to elucidate the exact mechanism of the immunomodulatory effects of STH on concurrent enteric microparasite Infection
L M Ortegamora - One of the best experts on this subject based on the ideXlab platform.
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occurrence of neospora caninum and toxoplasma gondii Infections in ovine and caprine abortions
Veterinary Parasitology, 2012Co-Authors: B Moreno, Esther Collantesfernandez, A Villa, A Navarro, Javier Regidorcerrillo, L M OrtegamoraAbstract:Neospora caninum and Toxoplasma gondii are closely related cyst-forming apicomplexan parasites identified as important causes of reproductive failure in cattle and small ruminants, respectively. Protozoan abortion in small ruminants is traditionally associated with T. gondii, but the importance of N. caninum remains uncertain. The aim of this study was to investigate the presence of N. caninum and T. gondii Infections in abortion cases in small ruminants submitted for diagnosis. For this purpose, 74 ovine and 26 caprine aborted foetuses were recovered from different areas in Spain. Foetal histopathology was used to detect the presence of Protozoal-associated lesions in brain. The presence of N. caninum and T. gondii was confirmed by PCR. Protozoal Infection was detected in 17 out of 100 (17%) foetuses examined by at least one of the diagnostic techniques used. Lesions suggestive of Protozoal Infection were observed in 10.8% (8/74) and 15.4% (4/26) of the ovine and caprine abortions respectively. N. caninum and T. gondii Infection was detected by PCR in 6.8% (5/74) and 5.4% (4/74) of sheep foetuses, respectively, of which five showed Protozoal-associated lesions. N. caninum DNA was detected in 11.5% (3/26) of goat foetuses, of which two showed Protozoal-associated lesions, whereas T. gondii DNA was detected in one goat foetus with no lesions. The simultaneous presence of N. caninum and T. gondii DNA was detected in one sheep foetus with severe lesions. This study demonstrates that N. caninum plays a significant role in abortion in small ruminants in the studied population. In addition, our results highlight the importance of differentiating between protozoa whenever characteristic lesions are observed.
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evaluation of neospora caninum and toxoplasma gondii Infections in alpaca vicugna pacos and llama lama glama aborted foetuses from peru
Veterinary Parasitology, 2007Co-Authors: Enrique Serranomartinez, Esther Collantesfernandez, A Chavezvelasquez, Antonio Rodriguezbertos, E Casasastos, V Riscocastillo, R Rosadioalcantara, L M OrtegamoraAbstract:Abstract The aim of this study was to investigate the participation of Neospora caninum and Toxoplasma gondii in abortion cases of Peruvian llamas and alpacas. Fifteen aborted foetuses were recovered from two main rearing areas of camelids in Peru (Central or South Andean region). Foetal histopathology was used to detect the presence of Protozoal-associated lesions in target organs. N. caninum and T. gondii Infections were confirmed by immunohistochemistry (IHC) combined with PCR and by PCR alone, respectively. The influence of the species (llama and alpaca), foetal age (first, second and third gestational periods) and geographical location (Central or South Andean region) of the foetuses was also studied. Thirteen of the samples (26%, 13/50) showed lesions suggestive of Protozoal Infection. N. caninum Infection was detected by either IHC or specific PCR in 14 out of 50 foetuses (28%), of which 8 also showed Protozoal-associated lesions. T. gondii DNA was not detected in any of the foetuses analysed. Protozoal Infection was more frequent in the foetuses from the second gestational period ( P F -test). No significant association was observed between Protozoal Infection and species or geographical location ( P > 0.05, χ 2 test). The results of the present study indicate that neosporosis should be included during the differential diagnosis of abortion in llamas and alpacas.
