Molecular Screening of Arthropod-Borne Pathogens in Domestic Cats from Northeast of Mexico: First Report of Infection and Coinfection in the Country

Background: Cat-associated pathogens transmitted by arthropods are of global public and veterinary health importance. Cats, as well as dogs, have historically coexisted with humans in rural and urban environments. However, studies on microorganisms associated with cats are much less extensive than those on dogs. Materials and Methods: Therefore, the present study aims to document natural infections of Anaplasma , Bartonella , Ehrlichia , and Rickettsia in cats ( Felis catus ) using PCR in northeastern Mexico. Blood samples were collected from cats with the support of the Canine and Feline Control Centers and veterinary clinics. Specific pathogens were amplified by PCR, and some positive samples were sequenced. Results: A total of 250 cats were obtained from three municipalities in Nuevo Leon, Mexico. Specific PCR testing showed that 33.6% (84/250) cats tested positive for at least one of the pathogens. The overall natural pathogen infection rates were Ehrlichia with 20.8% (52/250), followed by Anaplasma with 8% (20/250), Bartonella with 3.2% (8/250), and Rickettsia with 1.6% (4/250). Phylogenetic analysis placed the Bartonella sequence within a well-supported B. quintana clade . The partial 16S rRNA sequence obtained from Ehrlichia was conservatively classified as Ehrlichia sp. closely related to E. chaffeensis . Conclusion: These findings document exposure or infection of cats with multiple arthropod-borne bacteria and support continued molecular surveillance using additional discriminatory loci.