Publications by authors named "Alexandre J Dasilva"

There is a critical need for developing new malaria diagnostic tools that are sensitive, cost effective and capable of performing large scale diagnosis. The real-time PCR methods are particularly robust for large scale screening and they can be used in malaria control and elimination programs. We have designed novel self-quenching photo-induced electron transfer (PET) fluorogenic primers for the detection of P.

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Background: In 2006, a pediatric diarrhea outbreak occurred in Botswana, coinciding with heavy rains. Surveillance recorded a 3 times increase in cases and a 25 fold increase in deaths between January and March. Botswana has high HIV prevalence among pregnant women (33.

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Effluents from a small-scale free-surface flow constructed wetland, used for polishing of secondary treated wastewater, contained significantly higher concentrations of potentially viable Giardia duodenalis cysts and Enterocytozoon bieneusi spores than did wetland influents consisting of secondary treated wastewater. Zoonotic Assemblage A of G. duodenalis cysts was identified in wetland inflows, while Assemblage A and two nonhuman infective Assemblages (i.

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In order to assess the applicability of multiplexed fluorescence in situ hybridization (FISH) assay for the clinical setting, we conducted retrospective analysis of 110 formalin-stored diarrheic stool samples from human immunodeficiency virus (HIV)/AIDS patients with intestinal microsporidiosis collected between 1992 and 2003. The multiplexed FISH assay identified microsporidian spores in 94 of 110 (85.5%) samples: 49 (52.

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The epidemiological importance of increasing reports worldwide on Cryptosporidium contamination of oysters remains unknown in relation to foodborne cryptosporidiosis. Thirty market-size oysters (Crassostrea virginica), collected from each of 53 commercial harvesting sites in Chesapeake Bay, MD, were quantitatively tested in groups of six for Cryptosporidium sp. oocysts by immunofluorescent antibody (IFA).

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Long term field studies and laboratory experiments demonstrated that synanthropic filth flies can mechanically transmit infectious oocysts of Cryptosporidium parvum, an anthropozoonotic protozoan parasite which significantly contributes to the mortality of immunocompromised or immunosuppressed people. C. parvum oocysts are acquired from unhygienic sources, and can pass trough fly gastrointestinal track without alteration of their infectivity and can be subsequently deposited on visited surfaces.

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Zebra mussels ( Dreissena polymorpha) from throughout the Shannon River drainage area in Ireland were tested for the anthropozoonotic waterborne parasites Cryptosporidium parvum, Giardia lamblia, Encephalitozoon intestinalis, E. hellem, and Enterocytozoon bieneusi, by the multiplexed combined direct immunofluorescent antibody and fluorescent in situ hybridization method, and PCR. Parasite transmission stages were found at 75% of sites, with the highest mean concentration of 16, nine, and eight C.

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Cryptosporidiosis, a zoonotic diarrheal disease, significantly contributes to the mortality of people with impaired immune systems worldwide. Infections with an animal-adapted genotype (Genotype 2) of Cryptosporidium parvum were found in a human population in Uganda that shares habitats with free-ranging gorillas, from which the same genotype of C. parvum had been recovered previously.

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Synopsis of recent research by authors named "Alexandre J Dasilva"

  • - Recent research by Alexandre J Dasilva primarily focuses on the molecular diagnostics of infectious diseases, including innovative techniques like photo-induced electron transfer (PET) for more effective malaria detection, addressing the need for cost-efficient diagnostic tools.
  • - Dasilva's work also highlights the epidemiology of zoonotic parasites and human pathogens, emphasizing studies on the transmission of Cryptosporidium parvum and the impact of environmental factors on outbreaks, such as during a severe diarrhea outbreak in Botswana.
  • - His research spans diverse geographic contexts, from identifying human waterborne parasites in the Shannon River in Ireland to investigating zoonotic parasite interactions in regions sharing habitats with endangered species, illustrating a commitment to understanding the complexities of pathogens in human and ecological health.