Contamination and Viability of Toxocara sp. in Feces Collected from Public Parks, Streets and Dogs in Tejupilco at the Subhumid Tropic of Mexico

Toxocara canis and Toxocara cati in domestic dogs and cats in the United States, Mexico, Central America and the Caribbean: A review

Toxocara prevalence ranges from 0 to >87% and 0 to >60% in dogs and cats, respectively, within the United States, Mexico, Central America and the Caribbean. Higher prevalence occurs in animals less than 1 year of age. Overall, prevalence is higher in cats compared to dogs. The lowest prevalence occurs in the US owned dog population. Specific populations in this industrialized nation, in animal shelters or resource-limited locations, have prevalences similar to those seen in populations from other regions reviewed here. Conversely, subpopulations in Central America and the Caribbean have very low prevalence. Apparent contributors to prevalence, excluding animal age and climate, are socio-economic factors, attitudes towards pet management and animal population density. The lack of data from some regions pose a challenge in assessing trends; however, with the exception of the US owned dog population, there is no strong indication of any decrease in prevalence from historical levels.

Presence of anti-Toxocara canis antibodies and risk factors in children from the Amecameca and Chalco regions of México

BACKGROUND

Toxocariasis is a zoonotic disease that poses a threat to public health worldwide. This disease primarily affects children and is caused by the presence in the digestive tract of a common roundworm of dogs, Toxocara canis, or cats, Toxocara cati. Toxocara is responsible for the presentation of various syndromes in humans depending on the affected organs.

METHODS

In this study, the prevalence of anti-T. canis antibodies was investigated in children aged 3-16 years from semirural populations in the municipalities of Amecameca and Chalco in México. An ELISA was used to determine the presence of anti-T. canis antibodies in blood samples.

RESULTS

Of the 183 sera obtained for this study, 22 were positive for anti-T. canis antibodies (12.02%). Of these, 6.50% were from males and 5.4% were from females. Risk factors were investigated and it was found that living near a cattle operation had a statistically significant association with (Chi(2) = 5.51 and p = 0.01) and was a risk factor for (OR = 4.25, p = 0.02) seropositivity to T. canis. Keeping dogs with short hair (Chi(2) = 3.24 and p = 0.07) showed a tendency toward seropositivity for T. canis, as did the habit of sleeping with pets (Chi(2) = 3.46 and p = 0.06).

CONCLUSIONS

Seropositivity to T. canis was confirmed in children in the Amecameca and Chalco regions of México and the risk factors were identified. These findings provide important insight into the prevalence and spread of this zoonotic parasite.

Soil contamination by Toxocara spp. eggs in a University in Mexico City

The contamination levels of Toxocara spp. eggs in soil samples from a university campus in Mexico City were evaluated and analysed according to garden size, and were related with the percentage of Toxocara spp. eggs and its viability according to the soil characteristics. A total of 1458 soil samples collected in 15 gardens (six large and nine small) were analysed by sedimentation-flotation with zinc sulphate solution on at 33%. Contamination was low (12.9%), and egg viability was high (65.5%). The size of the garden had no influence on the presence and viability of Toxocara spp. eggs. Contamination was negatively correlated with the percentage of vegetation (r = -0. 61, P < 0.01) and the viability was negatively associated with the percentage of clay in the soil samples (r = -0.51, P < 0.04). The size of the garden did not influence the presence and viability of Toxocara spp. eggs.