Exploring the Zoonotic Risk of <i>Bartonella henselae</i> : A Serological and Molecular Investigation of Veterinary Personnel and Companion Cats in South Korea

<i>Bartonella</i> species are known as candidates for zoonotic transmission, and cats serve as the main reservoir for <i>Bartonella henselae</i>, the primary causative agent of cat scratch disease (CSD). However, research on the transmission of bartonellosis to humans remains very limited. In East Asia, there is a lack of comprehensive studies regarding the prevalence of <i>B. henselae</i> infection and its associated risk factors among companion cats, their owners, and individuals working in veterinary professions. This study aimed to investigate both the molecular and seroprevalence of <i>B. henselae</i> in veterinary personnel and companion cats in South Korea, along with a questionnaire-based analysis of transmission risk factors. Blood and saliva samples were collected from humans, whereas blood, saliva, claw, and fecal samples were obtained from cats. Seroprevalence and molecular prevalence were measured for all these samples. Additionally, participants were required to complete an epidemiological information questionnaire related to CSD. The study enrolled 300 veterinary professionals and 126 companion cats owned by them. The serum IgG prevalence in humans was 64.6% (190/294), whereas, in cats, it was 5.5% (6/108). The molecular prevalence in human blood and saliva was 3% (9/298) and 1.7% (5/298), respectively. In cats, it was 10.1% (12/119) for blood, 0% (0/123) for saliva, 1.7% (2/119) for nails, and 4.5% (5/112) for feces. Phylogenetic analysis of the PCR-positive samples confirmed that all of them were <i>B. henselae</i>. This study demonstrates that Bartonella species are widespread among veterinary professionals in South Korea, highlighting their significance as zoonotic pathogens. Given the potential for indirect transmission from cats, enhancing awareness of Bartonella exposure risk among veterinary personnel is warranted, along with emphasizing preventive education for cat owners, including strict ectoparasite control.