Multilocus Genotyping of Giardia duodenalis in Mostly Asymptomatic Indigenous People from the Tapirapé Tribe, Brazilian Amazon.

Little information is available on the occurrence and genetic variability of the diarrhoea-causing enteric protozoan parasite Giardia duodenalis in indigenous communities in Brazil. This cross-sectional epidemiological survey describes the frequency, genotypes, and risk associations for this pathogen in Tapirapé people (Brazilian Amazon) at four sampling campaigns during 2008-2009. Microscopy was used as a screening test, and molecular (PCR and Sanger sequencing) assays targeting the small subunit ribosomal RNA, the glutamate dehydrogenase, the beta-giardin, and the triosephosphate isomerase genes as confirmatory/genotyping methods. Associations between G. duodenalis and sociodemographic and clinical variables were investigated using Chi-squared test and univariable/multivariable logistic regression models. Overall, 574 individuals belonging to six tribes participated in the study, with G. duodenalis prevalence rates varying from 13.5-21.7%. The infection was positively linked to younger age and tribe. Infected children <15 years old reported more frequent gastrointestinal symptoms compared to adults. Assemblage B accounted for three out of four G. duodenalis infections and showed a high genetic diversity. No association between assemblage and age or occurrence of diarrhoea was demonstrated. These data indicate that the most likely source of infection was anthropic and that different pathways (e.g., drinking water) may be involved in the transmission of the parasite.

Isolation and genetic characterization of Toxoplasma gondii from free-ranging and captive birds and mammals in Pernambuco state, Brazil

Abstract Recent genetic population studies on Toxoplasma gondii in Brazil have shown large genetic variability. The objective of the present study was to isolate and genotypically characterize T. gondii from free-ranging and captive wild mammals and birds in Pernambuco state, Brazil. Fragments of heart, brain, skeletal muscle and diaphragm tissue from 71 birds and 34 mammals, which were either free-ranging or captive, were collected. Samples from 32 of these animals were subjected to bioassays in mice. Samples from the remaining 73 animals underwent biomolecular diagnosis, using PCR technique, targeting a repetitive DNA fragment of 529 bp in T. gondii. A non-virulent isolate (TgButstBrPE1) was obtained from a free-ranging striated heron (Butorides striata) and, based on primary samples, seven animals were found to be positive. The primary samples and the isolate obtained were subjected to PCR-RFLP using the markers SAG1, 53SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3. ToxoDB-RFLP genotype /13 from the striated heron isolate and Type BrIII genotype from a captive otter ( Lontra longicaudis) (PS-TgLonloBrPE1) were obtained. The present study describes the first isolation and genotypic characterization of T. gondii in free-ranging striated heron, and the first genotypic characterization of T. gondii in a captive otter.

Resumo Recentes estudos genéticos nas populações deste parasita no Brasil têm mostrado grande variabilidade genética. O objetivo do presente estudo foi isolar e caracterizar genotipicamente T. gondii de aves e mamíferos de vida livre e de cativeiro no estado de Pernambuco, Brazil. Fragmentos de tecido do coração, cérebro, músculo esquelético e diafragma de 71 aves e 34 mamíferos de vida livre ou cativeiro foram colhidos. Amostras de 32 destes animais foram submetidas a bioensaios em camundongos. As amostras dos 73 animais restantes foram submetidas a diagnóstico biomolecular usando a técnica de PCR, tendo como alvo o fragmento repetitivo de 529 pb do DNA de T. gondii. Dentre os 32 bioensaios conduzidos, obteve-se um isolado não-virulento (TgButstBrPE1) de um socozinho (Butorides striata ) de vida livre, e dentre as amostras primárias, sete animais foram positivos. As amostras primárias e o isolado foram submetidos a PCR-RFLP usando os marcadores SAG1, 53SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico e CS3. Foram obtidos o genótipo ToxoDB-RFLP /13 do isolado do socozinho e o genótipo Type BrIII de uma lontra (Lontra longicaudis) de cativeiro (PS-TgLonloBrPE1). O presente estudo descreve o primeiro isolamento e caracterização genotípica de T. gondii em socozinho de vida livre, e a primeira caracterização genotípica de T. gondii em lontra em cativeiro.

Toxoplasma gondii antibodies in wild rodents and marsupials from the Atlantic Forest, state of São Paulo, Brazil

Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and marsupials play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 48 marsupials, captured in the Atlantic Forest, São Paulo State, southeastern Brazil, were analyzed for the presence of T. gondii antibodies. Antibodies detected by the modified agglutination test (MAT 25) were found in 8.6% (13/151) of the rodents and 10.4% (5/48) of the marsupials, with titers ranging from 25 to 6400 and from 25 to 3200, respectively for the rodents and marsupials. Three of the eight species of rodents (Akodon spp., Oligoryzomys nigripesand Rattus norvegicus), and one from the four marsupial species (Didelphis aurita) presented positive animals. T. gondii was described for the first time in the rodent Oligoryzomys nigripes.

Toxoplasma gondii é um protozoário parasita que infecta animais de sangue quente, incluindo seres humanos. Pequenos roedores e marsupiais têm papel importante na epidemiologia do T. gondii, pois são fontes de infecção para os felídeos domésticos e selvagens. Amostras de soro de 151 roedores e 48 marsupiais, capturados na Mata Atlântica, Estado de São Paulo, Sudeste do Brasil, foram analisadas para a pesquisa de anticorpos anti-T. gondii. Os anticorpos foram detectados pelo Teste de Aglutinação Modificada (MAT 25), com 8,6% (13/151) dos roedores e 10,4% (5/48) dos marsupiais soropositivos, com títulos variando de 25 a 6.400 e de 25 a 3.200, respectivamente, para os roedores e os marsupiais. Três das oito espécies de roedores (Akodon spp., Oligoryzomys nigripes e Rattus norvegicus) e uma das quatro espécies de marsupiais (Didelphis aurita) apresentaram animais positivos. A presença de anticorpos anti-T. gondii foi descrita pela primeira vez no roedor Oligoryzomys nigripes.