Molecular epidemiology of Blastocystis isolated from animals in the state of Rio de Janeiro, Brazil

Abstract

The enteric protist Blastocystis is one of the most frequently reported parasites infecting both humans and many other animal hosts worldwide. A remarkable genetic diversity has been observed in the species, with 17 different subtypes (STs) on a molecular phylogeny based on small subunit RNA genes (SSU rDNA). Nonetheless, information regarding its distribution, diversity and zoonotic potential remains still scarce, especially in groups other than primates. In Brazil, only a few surveys limited to human isolates have so far been conducted on Blastocystis STs. The aim of this study is to determine the occurrence of Blastocystis subtypes in non-human vertebrate and invertebrate animal groups in different areas of the state of Rio de Janeiro, Brazil. A total of 334 stool samples were collected from animals representing 28 different genera. Blastocystis cultivated samples were subtyped using nuclear small subunit ribosomal DNA (SSU rDNA) sequencing. Phylogenetic analyses and BLAST searches revealed six subtypes: ST5 (28.8%), ST2 (21.1%), ST1 and ST8 (19.2%), ST3 (7.7%) and ST4 (3.8%). Our findings indicate a considerable overlap between STs in humans and other animals. This highlights the importance of investigating a range of hosts for Blastocystis to understand the eco-epidemiological aspects of the parasite and its host specificity.

Prevalence of Blastocystis sp. infection in several hosts in Brazil: a systematic review and meta-analysis

“…Our phylogenetic inference revealed a relationship between ST1 and ST2 as well as between ST8 and ST4. Such a relationship was also proposed in a recent study that analyzed SSU rDNA sequences in fecal samples from animals of various orders [36]. After analyzing sequences from several STs in fecal samples from humans and other mammals, birds, reptiles and cockroaches, we observed a considerable overlap between different hosts and the Blastocystis subtypes.…”

“…Our study retrieved 1740 manuscripts using the search strategies employed. After the eligibility criteria were applied (duplicate texts, articles related to other topics, text excluded based on the review or methodological quality criteria), 40 studies were retained for analysis (Table 1) [9,36,37,. Of these 40 studies, 35 evaluated the prevalence of Blastocystis sp.…”

“…Valença-Barbosa et al [36] Moura et al [37] Wild Valença-Barbosa et al [36] Subtotal (I^2 = .%, p = . )…”

“…Valença-Barbosa et al [36] Marietto-Gonçalves et al [79] 0. 21 rates, at 39.0% (95% CI: 21.0-56.0%; weight 47.31%), followed by birds at 18.0% (95% CI: 10.0-27.0%; weight 39.31%).…”

First Report on the Prevalence and Subtype Distribution of Blastocystis sp. in Edible Marine Fish and Marine Mammals: A Large Scale-Study Conducted in Atlantic Northeast and on the Coasts of Northern France

“…Because of this risk of zoonotic transmission, the prevalence and ST distribution of Blastocystis sp. were reported in numerous surveys focused on various animal groups mainly housed in zoological gardens [15,16,20,[23][24][25]. Despite the strong interest in identifying animal reservoirs of human infection, aquatic animals such as edible marine fish and marine mammals have received very little attention so far, and available data are still scarce.…”