Prevalence of infection in dogs and egg environmental contamination in Baybay City, Leyte, Philippines.

is a parasitic gastrointestinal nematode of dogs causing toxocariasis in humans, a neglected tropical disease. This study examined the burden of infection in dogs and egg contamination in school playgrounds and public parks in Baybay City, Leyte, Philippines. Fecalysis and egg detection in soils were performed to determine the parasite prevalence in dogs and the environment. In addition, pet owner's survey and GIS mapping were employed to identify the risk factors of infection and map the parasite distribution. Fecalysis revealed a prevalence of 64.44% (95% CI: 48.78-78.13) at the barangay level and 17.96% (95% CI: 14.12-21.80) at the animal level. Rural areas showed a much higher prevalence than urban. Factors associated with high infection included dog's age, specifically puppy (2-8 mo) relative to young (> 8-24 mo) [Adjusted Odds Ratio (AOR): 2.282; 95% CI: 1.137-4.579;  = 0.020] and adult (> 24 mo) (AOR: 3.542; 95% CI: 1.714-7.319;  = 0.001), access to dirty water (AOR: 2.749; 95% CI: 1.575-4.798;  < 0.001), and non-deworming (AOR: 2.961; 95%: CI 1.009-8.684;  = 0.048). Furthermore, we observed high egg contamination in school playgrounds and public parks, with a prevalence of 51.11% (95% CI: 35.77-66.3) at the barangay level and 15.45% (95% CI: 10.67-20.23) in soil samples. This epidemiological study is the first in the central Philippines to report a high burden of infection in dogs and the environment, thus providing crucial data that will help understand the epidemiology of toxocariasis.The online version contains supplementary material available at 10.1007/s12639-022-01525-y.