Epidemiological aspects of Toxoplasma gondii infection in riverside communities in the Southern Brazilian Amazon

Abstract

Introduction:Toxoplasma gondii infection is widely prevalent in humans and other animals worldwide. Information on the prevalence of T. gondii infection is scarce in some regions of Brazil, including riverside communities along the Amazon River basin. Methods: The prevalence of T. gondii in 231 people, aged 1-85 years, who were living in four riverside communities along the Purus River, Lábrea, State of Amazonas, Brazil, was determined. Antibodies against T. gondii were assayed using a commercial enzyme-linked immunosorbent assay (ELISA) kit. The hearts and brains of 50 chickens, which were raised freerange in the communities, were pooled according to the community of origin and bioassayed in mice. The isolates were genotyped using polymorphisms at 12 nuclear markers (SAG1, 5' and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3). Results: The overall seroprevalence of T. gondii was 56.7% (131/231). IgG antibodies were presented by 117 (89.3%) and IgM by 14 (10.7%) of the 131 positive individuals. No association between age group and gender with prevalence was observed (chi-square test, p > 0.05); however, the comparison between localities showed that the seroprevalence of T. gondii was signifi cantly lower among the individuals living in the Boca do Ituxi (p < 0.05) community. Five isolates of T. gondii were obtained in the mouse bioassay, and genotyping revealed two complete genotypes that had not been described previously and three mixed isolates. Conclusions: These results support previous fi ndings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities.

Serosurvey of anti-Toxoplasma gondii and anti-HIV antibodies in homeless persons of southeastern Brazil

“…Interestingly, the seroprevalence of anti-T. gondii antibodies in the present study was lower than other Brazilian neglected populations, such as 131/231 (56.7%) persons of riverside communities in the northern and 119/148 (80.4%) indigenous persons in the central-western region [53,54]. In São Paulo, similar results were found, with 110/339 (32.4%) seropositive children from a lowsocioeconomic community [55].…”

Anti-Toxoplasma gondii antibodies in beef cattle slaughtered in the metropolitan region of Belém, Brazilian Amazon

“…A serological survey performed in the metropolitan area of the City of Belém (Pará state), involving 2.740 individuals showed that the seroprevalence of toxoplasmosis in the general population was approximately 78% (CARMO, 2011). In studies conducted in other urban or rural areas in the Brazilian Amazon the seroprevalence was lower than the Belém one, but still high (CAVALCANTE et al, 2006;FERREIRA et al, 2009;CARMO et al, 2010a;VITALIANO et al, 2015).…”

Surto de toxoplasmose aguda no Município de Ponta de Pedras, Arquipélago do Marajó, Estado do Pará, Brasil: características clínicas, laboratoriais e epidemiológicas

“…Na Região Amazônica brasileira, alguns estudos demonstraram que, por suas características ecoepidemiológicas, a prevalência da infecção é alta 13,14,15 e, ainda assim, surtos de toxoplasmose aguda têm ocorrido eventualmente. Em 2004, em Monte Dourado, no Estado do Pará, foi relatado um surto envolvendo 40 indivíduos com perfil clínico e sorológico compatível com a toxoplasmose aguda, cuja transmissão foi, provavelmente, por ingestão de alimentos e/ou a inalação de poeira contaminada com oocistos de T. gondii 16 .…”