Visceral larva migrans: a seroepidemiological survey in five municipalities of São Paulo State, Brazil Síndrome de larva migrans visceral: inquérito soroepidemiológico em cinco municípios do estado de São Paulo, Brasil

Abstract

An enzyme-linked immunosorbent assay (ELISA), employing antigens from Toxocara canis larvae and the absortion of suspected sera with Ascaris lumbricoides extracts was used in a seroepidemiological study performed in five municipalities of São Paulo State, Brazil (São Paulo, Campinas, Santos, Marília and Presidente Prudente) in order to determine the frequency of antibodies to Toxocara. In 2,025 blood samples collected, 806 proceeded from male subjects and 1,219 from females; 483 samples were collected from subjects under 15 years of age and the remaining 1,542 from subjects aged 15 years or over. Among the 2,025 sera investigated, 3.60% had antibodies to Toxocara at significant levels. A moderate predominance of infection with Toxocara among male subjects (3.72%) was observed, although the difference was not statistically significant when this rate was compared with that for female (3.28%). Related to age, a higher frequency of positive results was detected among subjects under 15 years (6.41%) against the older group (2.53%). A trend of more elevated rates of infection was observed in municipalities with high demographic densities (São Paulo, Campinas and Santos). Nevertheless, such findings only appeared to be statistically significant in subjects younger than 15 years.Realizou-se inquérito soroepidemiológico, para detecção de anticorpos anti-Toxocara, em 2.025 soros de indivíduos residentes em cinco municípios do Estado de São Paulo (São Paulo, Campinas, Santos, Marília e Presidente Prudente), através de técnica imunoenzimática (ELISA) e emprego de antígenos obtidos a partir de larvas de 2º - 3º estádio de Toxocara canis. Após absorção com extratos de Ascaris lumbricoides, revelou-se a presença de anticorpos anti-Toxocara, em níveis significativos, em 3,60% dos soros examinados, com predominância de indivíduos com idade inferior a 15 anos (6,41%). Observou-se, ainda, tendência a ocorrerem índices mais elevados de infecção por larvas de Toxocara entre indivíduos residentes em municípios com maior densidade demográfica (São Paulo, Campinas e Santos), especialmente no grupo com menos de 15 anos de idade.

Keywords

• Visceral Larva Migrans
• Toxocara sp.
• Toxocara canis
• Seroepidemiological survey