Human Toxocariasis in Rural Brazilian Amazonia: Seroprevalence, Risk Factors, and Spatial Distribution

Abstract

Abstract. This population-based cross-sectional study of 403 rural settlers in Brazilian Amazonia revealed an overall rate of IgG seropositivity to Toxocara canis excretory-secretory larval antigen of 26.8% (95% confidence interval [CI], 22.5-31.4%). Multilevel logistic regression analysis identified current infection with hookworm (odds ratio [OR], 2.32; 95% CI, 1.11-4.86) and residence in the most recently occupied sectors of the settlement (OR, 1.81; 95%CI, 1.3-2.52) as significant risk factors for Toxocara seropositivity; age > 14 years (OR, 0.46; 95% CI, 0.28-0.73) and the presence of cats in the household (OR, 0.57; 95% CI, 0.32-1.02) appeared to be protective. Two significant high-prevalence clusters were detected in the area, together comprising 38.9% of the seropositive subjects; households in the clusters had slightly lower socioeconomic status and were less likely to have cats as pets. The obstacles for controlling human toxocariasis in this and other tropical rural settings are discussed.

Anti-Toxocara spp. antibodies in an adult healthy population: serosurvey and risk factors in Southeast Brazil

“…The influence of cat ownership on a positive ELISA test has been less studied. In recent serosurveys in Brazil, having a cat was identified as both a protective factor and a risk factor [33,34] . A third survey in Poland [31] , but not a large country-wide study in the United States [25] found cat ownership to be a significant predictor of Toxocara seropositivity.…”

“…However, having a pet was not considered a risk/protective factor for toxocariasis. Keeping a dog in a household has been recognised as a risk factor in some [31,32] but not all surveys [21,33] . The influence of cat ownership on a positive ELISA test has been less studied.…”

A Systematic Review of Toxocariasis: A Neglected But High-Prevalence Disease in Brazil

“…10,[24][25][26][27][28][29][31][32][33][34][36][37][38][39][40][41][42][43][44] One study did not describe the diagnostic methodology applied. 35 As T. canis and T. cati cannot be distinguished serologically, we identified the study population as having toxocariasis.…”

Toxocariasis in the Americas: Burden and Disease Control

“…The different reports indicate seroprevalence rates ranging from 2.8 % to 54.8 %, identifying associated risk factors with the presence of antibodies anti-Toxocara, in which stands the classicallyknown frequent contact with contaminated soils, interaction with dogs, bad hygiene habits, and in association with the last factor, socioeconomic conditions [38][39][40][41][42][43][44][45][46].…”