The burden of some of the most common zoonoses in primary care: a population-based study in Italy.

Background: Preventing and managing zoonoses mandate the combined efforts of physicians, veterinarians, and environmental and social scientists. The systematic recording of zoonoses in humans is rarely carried out through dedicated surveillance systems, and there is a need to boost awareness among general practitioners about these diseases. Companion animals, especially dogs and cats which constitute a reservoir for zoonotic infective agents, are frequently present in Italian families. We therefore conducted an assessment of the burden of certain zoonoses in primary care settings in Italy.

Methods: Using an Italian primary care database, we identified the active population aged 15 years or older in the database on 31 December 2022, the study index date. We calculated the lifetime prevalence of zoonoses transmissible by domestic animals through different vectors. These estimates were stratified by the presence of immunodeficiencies and the level of frailty in older adults.

Results: The most common zoonosis was Lyme disease (4.7 per 10 000) followed by rickettsioses (3 per 10 000). Leishmania and Bartonella-related infections showed prevalence lower than 1 out of 10 000. Those with a positive history of immunodeficiencies showed greater occurrence of zoonoses (7.60 vs. 5.05 per 10 000). The proportion of zoonoses increased according to frailty level, from 14.73 to 18.62 per 10 000 moving from fit to severe frailty.

Conclusions: These findings suggest that improved surveillance and greater awareness among healthcare providers should support general practitioner-veterinarian interactions to minimize zoonosis transmission, especially for immunodeficient and frail older patients. Main messagesDogs and cats, which are frequently found in Italian families, constitute a reservoir of zoonotic infective agents.Zoonoses in humans are rarely systematically recorded using surveillance systems and there are no dedicated surveillance systems in Italy for zoonotic diseases, especially for primary care.The most common zoonoses in Italian primary care settings were Lyme disease and rickettsioses.The proportion of zoonoses increased with frailty levels in older adults and was almost double in those with immunodeficiencies relative to the general population.Enhancing knowledge and establishing dedicated monitoring systems within primary healthcare, as well as interdisciplinary collaboration between general practitioners and veterinarians, are essential for the prevention and control of zoonotic diseases.