Epidemiological study of Toxocara canis infection in dogs in selected regions of Egypt

Background Toxocariasis caused by Toxocara canis is a common parasitic disease in dogs with important zoonotic implications. Although fecal examination is traditionally used for diagnosis, it has limitations in detecting prepatent, low-intensity, or intermittent infections. Therefore, serological testing was selected in this study as a more sensitive and time-efficient approach for assessing exposure at the population level. This study aimed to determine the seroprevalence of T. canis infection and identify associated risk factors among dogs in four Egyptian governorates. Methods A total of 409 dogs from Cairo, Qalyubia, Kafr El-Sheikh, and Gharbia were sampled. Serum samples were tested for anti- T. canis IgG antibodies using a sensitive immunoassay. Epidemiological and management-related risk factors, including age, sex, feeding practices, housing conditions, cohabitation with cats, coprophagy, and deworming history, were recorded and analyzed using univariate and multivariate logistic regression models. Results The overall seroprevalence was 25.9% (106/409; 95% CI: 21.91–30.38%), with the highest prevalence in Cairo (32.2%) and the lowest in Qalyubia (19%). Dogs older than 4 years showed the highest seropositivity (37.4%). Seroprevalence was significantly higher among dogs fed homemade food (36%), living outdoors (41.5%), cohabiting with cats (32.4%), exhibiting coprophagy (30.4%), and those without regular deworming (33%). No statistically significant differences were observed between male and female dogs. Multivariate logistic regression identified older age, outdoor living, cohabitation with cats, coprophagy, homemade diet, and irregular deworming as significant risk factors for infection. Conclusion The findings demonstrate substantial exposure of dogs to T. canis in the studied regions and highlight the cumulative impact of environmental and management-related risk factors. The use of serology provided a broader estimate of exposure than fecal examination alone. Regular deworming, improved feeding practices, and environmental hygiene are essential to reduce infection risk and minimize zoonotic transmission.