|Fiuza, Vagner Ricardo - Federal University - Brazil|
|Lopes, Carlos Wilson - Federal University - Brazil|
|Cosendey, Rachel Ingrid - Federal University - Brazil|
|Oliviera, Francisco - Federal University - Brazil|
Submitted to: Research in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/6/2016
Publication Date: 6/7/2016
Citation: Fiuza, V., Lopes, C., Cosendey, R., Oliviera, F., Fayer, R., Santin, M. 2016. Zoonotic Enterocytozoon bieneusi Genotypes found in Brazilian sheep. Research in Veterinary Science. 107:196-201.
Interpretive Summary: Microsporidia comprises a diverse group of obligate intracellular parasites that infect all major animal groups from invertebrates to fish to birds and mammals, including domesticated animals and humans. Among Microsporidia, Enterocytozoon bieneusi is the most frequently detected species in humans. It has also been reported worldwide in animals of veterinary importance bringing into question the possible role of animal reservoirs in the epidemiology of this pathogen. The objective of this study was to determine the prevalence of this parasite and identify the genotypes present in sheep in the State of Rio de Janeiro (Brazil) to better understand what risks sheep represent in transmission of E. bieneusi, since there is no such information to date in South America. One hundred and twenty five samples of sheep feces were collected from 10 farms located in the State of Rio de Janeiro. The presence of E. bieneusi was determined by polymerase chain reaction (PCR) and all PCR-positive specimens were sequenced to determine the genotype. Twenty-four sheep were E. bieneusi positive. A higher prevalence was observed in lambs than in older sheep. Gene sequence analysis conducted in all samples positives by PCR revealed the presence of six genotypes; four known E. bieneusi genotypes (BEB6, BEB7, I, and LW1) and two novel genotypes (BEB18 and BEB19). These results constitute the first molecular characterization of E. bieneusi in sheep in South America. The identification of genotypes in Brazilian sheep that have previously been reported in humans suggest a potential risk of zoonotic transmission in this area.
Technical Abstract: 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 in 8/10 (80%) farms from three diverse locations. A significantly greater number of lambs were found infected than older sheep (P=0.0036); most of the lambs were less than 6 months of age. Farms with an intensive production system had a lower prevalence (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 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.