Toxocara canis infection in dogs and risk of human toxocariasis, Honduras

Abstract

Background. A case of human toxocariasis prompted a study of Toxocara canis and other zoonosis in dogs in Honduras. Objective. Document the prevalence of T. canis in pets, in a commercial dog kennel and free-roaming dogs in Tegucigalpa, Tatumbla, Zambrano and Danli. Methodology. During 12 non consecutive months (March 2012-Oct 2013) a parasitologist and medical students collaborated in the collection and examination of fresh fecal samples of dogs from owners (n=82), a commercial kennel (n= 69) and street dogs (n= 52). Stools were transported to and examined microscopically at the Parasitology Service of the University Hospital by a direct smear, and concentration by passive hypertonic saline flotation in all and stained by acid resistant modified method in 18 samples. Results. A total of 34.7% (72/207) feces were positive for different parasitic infections, street dogs more infected (36, 64.2%) than kennel dogs (31, 44.9%) or domestic pets (15, 18.2%). Overall T. canis infection prevalence was 3.8%, with 8.9% (5 cases) in street dogs, 2.4% (2 cases) in pets and 1.4% (one case) in the kennel. Ancylostomiasis (42 /207, 20.2%) was more prevalent in street dogs (28 cases, 50%) and pets (14.6%, 12 cases), than the kennel (2.8%, 2 cases). Giardia duodenalis cysts were recognized in 11 samples (5.9%) as were Trichuris vulpis eggs (0.9%), apicomplexan oocysts (5.9%) and a trichomonad species (3.3%), as were two cestode infections (0.9%). Conclusion. First documented T. canis cases and other zoonotic infections in dogs in Honduras exposed the need to develop better clinical and laboratory capacity to diagnose and treat human toxocariasis and stimulate veterinary participation for the control of zoonosis in dogs in Honduras.