Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are typical retroviruses that are transmitted horizontally among felines. FIV results in symptoms of immunodeficiency such as weight loss, chronic lesions, opportunistic infections, and neurological abnormalities, while FeLV is known to cause a variety of neoplastic and nonneoplastic diseases in cats, such as thymic lymphoma, multicentric lymphoma myelodysplastic syndromes, acute myeloid leukemia, aplastic anemia, and immunodeficiency. The prevalence and genetic diversity of FIV and FeLV in stray cats have not been investigated. In this study, polymerase chain reaction and enzyme-linked immunosorbent assay were used to test 198 blood samples from stray cats from Harbin, China, for FIV infection, FeLV seropositivity, and the prevalent subtypes of FIV. The gag capsid amino terminus and env V3-V5 regions of FIV samples were used to perform phylogenetic analysis. In total, 3% (6/198) of the stray cats from five districts of Harbin was PCR- were ELISA-positive for FIV. The FeLV positivity rate was 1% (2/198). Phylogenetic analysis of the gag and env sequences showed that cats were infected with FIV subtype A. This is the first study examining the prevalence rates of FIV and FeLV and the prevalent subtypes of FIV of stray cats in Harbin. These studies will enrich the epidemiological understanding of FIV and FeLV.

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