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

Abstract

Background: Blastocystis sp. affects a wide variety of animals and is the most common protozoan in human fecal samples with potential pandemic distribution. In the present study, a systematic review and meta-analysis were conducted to determine the prevalence and distribution of Blastocystis sp. in different classes of hosts in Brazil. Methods: Studies that analyzed hosts of various classes, including humans, domestic animals, wild animals or captive animals, were considered. The pooled prevalence of Blastocystis sp. infection was estimated by random effects models. Results: For humans, similar prevalence rates were found for males (31.0%, 95% CI: 17.0-45.0%; weight 10%) and females (28.0%, 95% CI: 16.0-41.0%; weight 10%); the state of Mato Grosso do Sul showed the highest prevalence, with 41.0% positivity (95% CI: 36.0-46.0%; weight 2.9%). The prevalence among immunocompromised patients was 5.0% (95% CI: 3.0-7.0%; weight 10%), and the most common cause of immunosuppression was hemodialysis, with 23.0% (95% CI: 17.0-29.0%; weight 12.4%). Among classifications according to interaction with humans, wild and domestic animals presented values of 19.0% (95% CI: 7.0-31.0%; weight 42.6%) and 17.0% (95% CI: 13.0-21.0%; weight 29.6%), respectively. Among these animals, mammals (39.0%, 95% CI: 21.0-56.0%; weight 47.3%) and birds (18.0%, 95% CI: 10.0-27.0%; weight 39.3%) exhibited the highest prevalence. Phylogenetic analysis of Blastocystis sp. revealed greater genetic diversity for clades of subtypes (STs) ST1, ST2 and ST3. Conclusions: The overall prevalence of Blastocystis sp. in the Brazilian human population was 24%, which reflects the reality in the South, Southeast and Midwest regions, where prevalence rates of up to 40% were found. Among animals, mammals and birds exhibited the highest prevalence.

Current status of Blastocystis sp. in animals from Southeast Asia: a review

“…While chickens were the most studied, a prevalence of 100% was reported in ostriches and a range from 3.8 to 40% in the other birds (Table 1 ). These figures are comparable with records from Australia (Stenzel et al 1994 ), Brazil (Bergamo do Bomfim and Machado do Couto 2013 ; Zanetti et al 2020 ), Iran (Asghari et al 2019 ), and Lebanon (Greige et al 2018 ). In Malaysia, the prevalence of Blastocystis infection among free-range chickens was reported to be significantly higher than that of barn-reared chickens due to exposure of free-range chickens by their scavenging habits to environmental contamination (Farah Haziqah et al 2014 ).…”

Prevalência de Blastocystis spp. provenientes de amostras fecais de moradores de dois biomas mato-grossenses

“…As parasitoses intestinais apresentam frequências elevadas em países em desenvolvimento, como o Brasil, ocorrendo variações quanto à região de cada país, sendo influenciada pelas condições de saneamento básico, nível socioeconômico, graus de escolaridade, idade e os hábitos de higiene dos indivíduos (Machado et al 1999, Silva-Neto et al 2010, Zanetti et al 2020.…”

“…Uma meta-analise sobre infecção por Blastocystis spp. no Brasil, demonstrou que a prevalência combinada na população brasileira geral é de 24%, no Centro-Oeste, as maiores taxas foram encontradas nos estados de Mato Grosso do Sul (41,0%) e Mato Grosso (17,0%) (Zanetti et al 2020).…”

“…Os dados obtidos neste estudo em relação à positividade para Blastocystis spp. e o sexo dos indivíduos estão em consonância com outros descritos na literatura (Garcia et al 1984;Torres et al 1992, Zanetti et al 2020, demonstrando não haver diferença significativa entre a positividade e o sexo, indivíduos do sexo masculino e feminino podem ser acometidos por Blastocystis spp. na mesma proporção.…”

“…No Brasil, a presença de Blastocystis spp. já foi relatada em alguns estudos, seja em portadores hígidos ou em imunodeprimidos (Nascimento e Moitinho 2005;Aguiar et al 2007;Martins et al 2007, Cabrine-Santos et al 2016, Zanetti et al 2020, mas especialmente no território mato-grossense são poucos e incipientes os estudos que revelam a prevalência deste parasita, o que corrobora para o desconhecimento das peculiaridades inerentes ao protozoário. Averigua-se que seu potencial zoonótico, ou seja, sua capacidade de infectar diferentes espécies incluindo a habilidade de infectar humanos.…”