Levels of Toxocara Infections in Dogs and Cats from Urban Vietnam Together with Associated Risk Factors for Transmission.

The aims of the present study were to assess the prevalence of Toxocara infection in household cats and dogs, together with the presence of anti-Toxocara IgG antibodies in humans and the level of egg contamination in soil and vegetable samples from the local environment. Prevalence values of 47.8% of 253 cats and 37.7% of 284 dogs were recorded, together with 35.8% of eggs in soil samples, 25.0% in garden vegetables and in 56.3% of 16 dog-hair samples. The risk of the infection was higher for dogs and cats in households with egg-contaminated soil compared to those without evidence of soil contamination. The high prevalence of dog and cat Toxocara infection and their indiscriminate defecation behaviour contribute to a significant risk of transmission to humans as 58.7% of human blood samples were seropositive for Toxocara. Anthelmintic treatment of dogs and cats, plus educating household members, must be emphasized in any prevention programme in Vietnam.