An Integrated Study of <i>Toxocara</i> Infection in Honduran Children: Human Seroepidemiology and Environmental Contamination in a Coastal Community

• Main Authors: Sergio A. Hernández, José A. Gabrie, Carol Anahelka Rodríguez, Gabriela Matamoros, María Mercedes Rueda, Maritza Canales, Ronald Mergl, Ana Sanchez
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Tropical Medicine and Infectious Disease
• Subjects: <i>Toxocara</i>; toxocariasis; zoonosis; seroepidemiology; neglected tropical diseases; Honduras
• Online Access: https://www.mdpi.com/2414-6366/5/3/135

(1) Background: Infections caused by <i>Toxocara canis</i> and <i>T. cati</i> are considered zoonoses of global importance. Reports from North and South America indicate that human infections are widespread in both continents, but epidemiological information from Central America is still lacking. (2) Methodology: In the present cross-sectional multi-year study, we aimed to undertake the first seroepidemiological and environmental study on toxocariasis in Honduras. This included the determination of seroprevalence of anti-<i>Toxocara</i> spp. antibodies in children using a <i>Toxocara</i> spp. purified excretory-secretory antigens enzyme-linked immunosorbent assay (TES-ELISA) and a confirmatory Western blot. As well, through statistical analysis including logistic regression we aimed at identifying relevant biological and epidemiological factors associated with seropositivity. The study also entailed detection of parasites’ eggs in the soil samples both through Sheather’s concentration method and a nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. (3) Results: The study was undertaken in a coastal community of Honduras in 2 different years, 2015 and 2017. A total of 88 healthy schoolchildren completed the study, with participation of 79% (73/92) and 65% (46/71) of the student body in 2015 and 2017, respectively. Thirty-one children participated in both years (i.e., dual participants). Through both serological tests, seropositivity was confirmed in 88.6% (78/88) of children. Due to the high number of seropositives, logistic regression analysis was not possible for most socio-economic and epidemiological variables. Eosinophilia, on the other hand, was associated with seropositivity, independently of other intestinal helminthic infections. Continued seropositivity was observed in most of the dual participants, while seroconversion was determined in 8 of these children. Microscopic examination of soil samples did not yield any positive results. Through nested PCR-RFLP, 3 of the 50 samples (6%) were positive for <i>Toxocara</i> spp.; two were identified as <i>T. canis</i> and one as <i>T. cati</i>. (4) Conclusions: This work documents for the first time, high levels of human exposure to <i>Toxocara</i> spp. in Honduras. These findings, along with the country’s favorable epidemiological conditions for this zoonosis, emphasize the need for more research to determine whether this infection is underreported in the country.