Toxoplasmagondii oocysts, Giardia cysts and Cryptosporidium oocysts in outdoor swimming pools in Brazil.

The accidental ingestion of treated recreational water is an important transmission route of waterborne protozoa worldwide. The present study aimed to provide the first evaluation of swimming pools in Brazil, analysing the presence of pathogenic protozoa (Toxoplasma gondii, Cryptosporidium spp. and Giardia spp.) by parasitological and molecular methods. A total of 57 samples were collected from 21 public swimming pools, either directly from the pool or filter backwash water and concentrated using the membrane filtration technique. Giardia cysts and Cryptosporidium oocysts were visualized by direct immunofluorescence assay after purification by immunomagnetic separation. Toxoplasma gondii oocysts were detected by autofluorescence visualization using the supernatant discarded during the purification step as a sample. Positive samples were submitted to molecular analysis. The molecular markers were used: SSU-rRNA, tpi, gdh and bg, for Giardia DNA amplification, and 18S rRNA gene fragment amplification was used for the Cryptosporidium oocysts. The 529-bp repeat element (REP529) fragment and the 35-fold repetitive B1 gene were employed as a target for T. gondii. Amplified products were submitted to sequencing and phylogenetic analysis. Giardia cysts were detected in 19.0% and Cryptosporidium oocysts in 9.5% of swimming pools. In one swimming pool (4.7%), both protozoa were detected on at least one occasion. Structures similar to T. gondii oocysts were detected in 33.3% of the samples, ranging from one to 23 per slide. Giardia was confirmed by DNA amplification in three swimming pools; Giardia duodenalis Assemblage A was identified by the phylogenetic positioning of the ß-giardin gene. Toxoplasma gondii DNA was detected in 14.2% of swimming pools. The present study represents the first report of the occurrence of T. gondii oocysts in swimming pools. Recreational activity in swimming pools contaminated by chlorine-resistant protozoa can represent a high risk of infection for bathers and swimmers.

Occurrence of zoonotic Enterocytozoon bieneusi in cats in Brazil / Ocorrência de Enterocytozoon bieneusi zoonótico em gatos no Brasil

Abstract Enterocytozoon bieneusi is an opportunistic intestinal pathogen that infects humans and a wide variety of animals worldwide. Our aim in this study was to investigate the occurrence of E. bieneusi in a domestic cat population in Campo Grande, Mato Grosso do Sul, Brazil. Sixty fecal samples from diarrheic cats were subjected to polymerase chain reaction (PCR) and the amplicons were sequenced for identification. E. bieneusi was detected in two samples (3.3%), both identified as genotype D. This genotype has already been reported in animals and humans and is considered a zoonotic genotype. Our findings represent the first report of E. bieneusi in domestic cats in Brazil, reinforcing the importance of identifying this agent as a source of infection in animals and humans.

Resumo Enterocytozoon bieneusi é um patógeno intestinal oportunista que infecta humanos e uma variedade de animais em todo o mundo. O objetivo no presente estudo foi investigar a ocorrência de E. bieneusi em uma população de gatos domésticos em Campo Grande, Mato Grosso do Sul, Brasil. Sessenta amostras fecais de gatos diarréicos foram submetidas a reação em cadeia da polimerase (PCR) e os produtos de amplificação foram sequenciados para identificação molecular. E. bieneusi foi detectado em duas amostras (3,3%), ambos identificados como genótipo D. Esse genótipo tem sido relatado em animais e humanos e é considerado um genótipo zoonótico. Nossos resultados representam a primeira descrição de E. bieneusi em gatos domésticos no Brasil, reforçando a importância desse agente como fonte de infecção para animais e humanos.

Occurrence of zoonotic Enterocytozoon bieneusi in cats in Brazil.

Enterocytozoon bieneusi is an opportunistic intestinal pathogen that infects humans and a wide variety of animals worldwide. Our aim in this study was to investigate the occurrence of E. bieneusi in a domestic cat population in Campo Grande, Mato Grosso do Sul, Brazil. Sixty fecal samples from diarrheic cats were subjected to polymerase chain reaction (PCR) and the amplicons were sequenced for identification. E. bieneusi was detected in two samples (3.3%), both identified as genotype D. This genotype has already been reported in animals and humans and is considered a zoonotic genotype. Our findings represent the first report of E. bieneusi in domestic cats in Brazil, reinforcing the importance of identifying this agent as a source of infection in animals and humans.

Pre-ozonation of source water: Assessment of efficacy against Giardia duodenalis cysts and effects on natural organic matter.

The protozoan Giardia duodenalis is one of the parasites of primary concern in drinking water treatment plants, due to its resistance to chlorination. Another matter of concern regarding chlorination of drinking water is the formation of disinfection by-products in the presence of precursors such as natural organic matter (NOM). In this study, the effects of ozonation (5 mg L-1) on G. duodenalis cysts in raw surface water from a drinking water treatment plant were evaluated, and the presence and alteration of NOM were assessed, as an indicative of the potential to prevent total organic halogen (TOX) formation during post-chlorination. Following ozone treatment, the presence of damaged cysts was observed by direct immunofluorescence assay (IFA) and confirmed by the molecular approach propidium monoazide-polymerase chain reaction (PMA-PCR). Using an animal model, analysis of the intestinal tissues revealed that 80% of the animals inoculated with ozonated water were positive for trophozoites. This study shows that analysis of intestinal fragments is imperative to accurately assess animal infection following inoculation of treated cysts. More importantly, considering the low infective dose of Giardia cysts in susceptible hosts, an ozone dosage usually applied in drinking water treatment plants did not completely inactivate G. duodenalis cysts in surface water. Nonetheless, the results suggest that competitive reactions with NOM have occurred, and the applied ozone dosage has proven useful to remove NOM reactivity, and thus prevent halogenated DBP formation during post-chlorination.

Enterocytozoon bieneusi detected by molecular methods in raw sewage and treated effluent from a combined system in Brazil.

BACKGROUND: Enterocytozoon bieneusi are the most common microsporidia associated with different clinical manifestations such as diarrhoea, respiratory tract inflammation and acalculous cholecystitis, especially in immunocompromised patients. Infection usually occurs by ingestion of food and water contaminated with spores, but can also result from direct contact with spores through broken skin, eye lesions, and sexual transmission, depending on the microsporidian species. Although there are reports of E. bieneusi found in humans and animals in Brazil, there are no published studies of environmental samples examined by molecular methods. OBJECTIVES: The purpose of this study was to verify the presence of E. bieneusi in raw sewage and treated effluent from a combined system by molecular methods. METHODS: Raw sewage and treated effluent samples collected from a combined system were analysed for the presence of E. bieneusi using the internal transcriber spacer (ITS) region of E. bieneusi by nested polymerase chain reaction. FINDINGS: The analysis revealed E. bieneusi presence and a novel genotype (EbRB) in one raw sewage sample and one treated effluent. MAIN CONCLUSIONS: The presence of E. bieneusi in final effluent indicates that the combined system may not remove microsporidian spores. This study is the first report of E. bieneusi in environmental samples in Brazil.

Enterocytozoon bieneusi detected by molecular methods in raw sewage and treated effluent from a combined system in Brazil

BACKGROUND Enterocytozoon bieneusi are the most common microsporidia associated with different clinical manifestations such as diarrhoea, respiratory tract inflammation and acalculous cholecystitis, especially in immunocompromised patients. Infection usually occurs by ingestion of food and water contaminated with spores, but can also result from direct contact with spores through broken skin, eye lesions, and sexual transmission, depending on the microsporidian species. Although there are reports of E. bieneusi found in humans and animals in Brazil, there are no published studies of environmental samples examined by molecular methods. OBJECTIVES The purpose of this study was to verify the presence of E. bieneusi in raw sewage and treated effluent from a combined system by molecular methods. METHODS Raw sewage and treated effluent samples collected from a combined system were analysed for the presence of E. bieneusi using the internal transcriber spacer (ITS) region of E. bieneusi by nested polymerase chain reaction. FINDINGS The analysis revealed E. bieneusi presence and a novel genotype (EbRB) in one raw sewage sample and one treated effluent. MAIN CONCLUSIONS The presence of E. bieneusi in final effluent indicates that the combined system may not remove microsporidian spores. This study is the first report of E. bieneusi in environmental samples in Brazil.

Zoonotic Enterocytozoon bieneusi genotypes found in brazilian sheep.

The presence of Enterocytozoon bieneusi in sheep has been reported in only three countries worldwide. The present study has found E. bieneusi in Brazilian sheep for the first time; in 24/125 (19.2%) fecal samples by PCR and on 8/10 (80%) farms from three diverse locations. A significantly greater number of lambs (34.1%) were found infected than older sheep (11.1%) (P=0.0036); most of the lambs were less than 6months of age. Farms with an intensive production system had a lower infection rate (10.5%) of infection than semi-intensive farms (23%), but this difference was not statistically significant. Sequencing analysis of the internal transcribed spacer (ITS) region of the rRNA gene revealed four known E. bieneusi genotypes (BEB6, BEB7, I, and LW1) and two novel genotypes (BEB18 and BEB19). Genotypes LW1 and BEB19 clustered within designated zoonotic Group 1 while genotypes BEB6, BEB7, I, and BEB18, and clustered within Group 2. BEB6 was the most prevalent (45.8%), followed by BEB7 (33.3%). Genotypes BEB6, I, and LW1 are zoonotic and can pose a risk to human health for immunocompromised individuals.

Compromised nutrition in gerbils infected by Cystoisospora felis detected through an animal performance analysis tool.

The impact of Cystoisospora felis infection on the nutritional efficiency of gerbils was studied. The variables weight gain and feed intake were measured during four weeks in 28 laboratory gerbils, of which 14 were inoculated with 3.5 × 10(5) sporulated oocysts of C. felis and the remaining 14 were controls. The animals from both groups were weighted, killed, eviscerated and had their carcasses and tissues weighted and compared. A modern tool designed for measuring nutritional performance of farm animals was applied. The results showed compromised nutritional efficiency of the infected animals within the first week after infection. The consequences of these results are discussed here, including the potential impact of infection on farm animals performance.

Compromised nutrition in gerbils infected by Cystoisospora felis detected through an animal performance analysis tool / Comprometimento nutricional em gerbis infectados por Cystoisospora felis detectado através de uma ferramenta de análise de desempenho animal

The impact of Cystoisospora felis infection on the nutritional efficiency of gerbils was studied. The variables weight gain and feed intake were measured during four weeks in 28 laboratory gerbils, of which 14 were inoculated with 3.5 × 10(5) sporulated oocysts of C. felis and the remaining 14 were controls. The animals from both groups were weighted, killed, eviscerated and had their carcasses and tissues weighted and compared. A modern tool designed for measuring nutritional performance of farm animals was applied. The results showed compromised nutritional efficiency of the infected animals within the first week after infection. The consequences of these results are discussed here, including the potential impact of infection on farm animals performance.

O impacto da infecção por Cystoisospora felis na eficiência nutricional de gerbis foi estudado. As variáveis ganho de peso e consumo de ração foram mensuradas durante quatro semanas em 28 gerbis de laboratório, dos quais 14 foram inoculados com 3,5 × 10(5) oocistos esporulados de C. felis e os 14 restantes serviram como controle. Os animais de ambos os grupos foram pesados, mortos, eviscerados e tiveram suas carcaças e tecidos pesados e comparados. Uma ferramenta moderna desenvolvida para mensurar o desempenho nutricional de animais de produção foi aplicada. Os resultados mostraram eficiência nutricional comprometida dos animais infectados na primeira semana após a infecção. As consequências destes resultados são discutidas aqui, incluindo o possível impacto de infecção no desempenho de animais de produção.

Molecular characterization of Cryptosporidium in Brazilian sheep.

Feces were collected from 125 sheep between January and December 2007, on ten farms in the State of Rio de Janeiro, Brazil, and examined for the presence of Cryptosporidium. Ninety samples were collected from lambs 2 to 6 months of age, and 35 were from sheep over 12 months of age. All samples were subjected to molecular analysis by polymerase chain reaction (nested PCR) in two steps of the SSU rRNA. Two samples (1.6%) from the lambs were positive, and after sequencing were identified as Cryptosporidium ubiquitum. This species has been reported worldwide and it is considered a zoonotic pathogen since it has been found and in several animal species and humans. However, because of the low frequency of C. ubiquitum found, the risk for public health in this region may not be high.

Infecção experimental de gerbis (Meriones unguiculatus) com nematódeos de ovinos: eficiência bionutricional / Experimental infection of jirds (Meriones unguiculatus) with larve of sheep nematodes: bio-nutritional efficiency

O parasitismo por nematódeos gastrintestinais constitui uma importante causa de danos à saúde e de perdas econômicas na produção de pequenos ruminantes. O modelo laboratorial para estudos de nematódeos de ruminantes utilizando gerbis (Meriones unguiculatus) torna-se mais adequado quando estes animais são imunossuprimidos. Os corticosteróides são drogas freqüentemente usadas na imunossupressão de animais de biotério. O índice de eficiência bionutricional é considerado um parâmetro efetivo para avaliar os efeitos de tratamentos sobre a performance nutricional dos animais. O objetivo deste trabalho foi avaliar a eficiência bionutricional de gerbis imunossuprimidos e infectados experimentalmente com larvas de nematódeos de ovinos. Os resultados indicaram que os animais que receberam a droga apresentaram maior número de nematódeos à necropsia que o grupo de animais apenas infectados. Não foi observado efeito nocivo da infecção sobre a performance dos animais. Os animais não infectados e que receberam a droga metilprednisolona tiveram performance significativamente menor que os não infectados que não receberam a mesma.

The gastrointestinal parasitism by nematodes constitutes an important cause of damages to the health and of economical losses in the production of small ruminants. Studies with nematodes of ruminants using jirds (Meriones unguiculatus) as a laboratorial model become more appropriate when the animals are immunossupressed. Corticosteroids are drugs quite used in the immunossuppression of biotery animals. The bio-nutritional efficiency index is considered an effective parameter to evaluate the effect of treatments on the animal nutritional performance. The objective of this work was to evaluate the bio-nutritional efficiency index of jirds immunossupressed and infected experimentally with larves of sheep nematodes. The results indicated that the animals that received the drug presented a major number of nematodes in necropsia in relation to the group of animals just infected. There was not harmful effect of infection on the performance of animals. The noninfected animals and treated with the drug methylprednisolone had a performance significantly lower than the noninfected animals and without drug application.