First report of multiple infection by Anaplasma platys, Bartonella henselae, and hemoplasmas in clinically healthy domestic cats from Southern Brazil

Hemoparasitoses in domestic cats are increasingly recognized as an emerging challenge for veterinary medicine and public health due to their subclinical persistence and zoonotic potential. This study aimed to detect Anaplasma platys, Bartonella henselae, and hemotropic mycoplasmas (Mycoplasma haemofelis [Mhf] and ‘Candidatus Mycoplasma haemominutum’ [CMhm]) in clinically healthy cats from Pelotas, southern Brazil, using molecular assays. A total of 151 blood samples collected between 2022 and 2024 were analyzed by conventional and nested PCR. Detection rates were 21.9% (33/151) for (A) platys, 15.2% (23/151) for (B) henselae, and 21.9% (33/151) for hemoplasmas, with a higher occurrence of CMhm (17.2%; 26/151) than Mhf (4.0%; 6/151). Coinfections occurred in 10.7% (16/151) of cats, including dual infections and one triple infection (0.7%; 1/151) involving (A) platys, (B) henselae, and CMhm. Statistical analyses showed that (A) platys infection was significantly associated with adult age (p = 0.01), (B) henselae was more frequent in kittens (p = 0.04), and hemoplasma infection occurred more often in males (p = 0.03). To our knowledge, this is the first molecular evidence of concurrent infection by (A) platys, (B) henselae, and ‘Candidatus Mycoplasma haemominutum’ in a cat from Brazil. These findings highlight the influence of host factors on pathogen dynamics and reinforce the need for molecular surveillance and integrated vector control under a One Health perspective.