Seroepidemiology of Toxocara canis infection among mountain aboriginal schoolchildren living in contaminated districts in eastern Taiwan

We conducted a seroepidemiological study of Toxocara canis infection among mountain aboriginal schoolchildren aged 7-12 years living in contaminated districts in eastern Taiwan. To detect sera IgG (> or =1:64) we used a T. canis larval excretory-secretory antigen-based enzyme-linked immunosorbent assay. A short questionnaire elicited information on the practices of raising dogs, playing with soil, eating raw vegetables, or whether the child normally washed his/her hands before eating. The overall seroprevalence was quite high, reaching 76.6% (252/329). Neither age nor gender seemed to be important factors related to a positive serology. Aboriginal schoolchildren who raised dogs (OR=1.83, 95% CI: 1.04-3.19, P=0.03), or played with soil (OR=2.52, 95% CI: 1.49-4.25, P <0.001) seemed to be more susceptible to T. canis infection than those who did not. Children who habitually washed their hands before eating (OR=0.57, 95% CI: 0.33-0.97, P=0.04) had a lower chance of acquiring T. canis infection than those who did not.