High Positivity Rate for Leptospira Infection in Symptomatic Urban Owned Dogs in Guayaquil, Ecuador

Leptospirosis is a zoonotic disease caused by spirochete bacteria of the genus Leptospira, with a wide global distribution. In Ecuador, leptospirosis is endemic, particularly in low-resource tropical areas, and multiple animal reservoirs have been identified either in rural or urban areas, including stray dogs. In this study, a total of 81 domestic dogs presenting clinical manifestations compatible with leptospirosis were recruited at the Municipal Center for Animal Welfare in Guayaquil, Ecuador, in 2023. A survey regarding clinical, demographic, and environmental risk factors was filled in by every dog's owner; urine and blood samples were collected for pathogenic Leptospira diagnosis by qPCR for lipL32, rrs, and secY gene targets. A very high (62.96%) positivity rate for Leptospira infection was found. Almost 90% of the dogs were not vaccinated against Leptospira. Although the animals exhibited multiple clinical signs, none showed a statistically significant association with Leptospira positivity, confirming the nonspecific presentation of the disease and its potential for misdiagnosis. The consumption of bulk food emerged as a significant environmental risk factor only in the multivariate logistic regression and not in the univariate analysis, suggesting the need for improved food safety practices. Moreover, we reported very frequent close-contact behaviors between owners and dogs. Overall, our study underscores the potential role of owned urban dogs as reservoirs of Leptospira in the city of Guayaquil in Ecuador, emphasizing the need for public health policies to increase awareness and improve diagnosis in domestic animals under a comprehensive One Health vision.