Molecular survey on vector-borne pathogens in clinically healthy stray cats in Zaragoza (Spain)

Background In Europe, feline vector-borne infections are gaining importance because of the changing climate, expanding habitats of potential vectors and expanding pathogen reservoirs. The main objective of this study was to assess the prevalence of vector-borne pathogens (VBPs) in stray cats in Zaragoza, Spain, and to investigate potential risk factors for infection, including feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV). Methods Blood samples from stray cats presented to the veterinary faculty in Zaragoza between February 2020 and 2022 were tested by polymerase chain reaction (PCR) for the presence of Anaplasma phagocytophilum , Anaplasma platys , Bartonella henselae , Ehrlichia canis , Rickettsia spp., haemotropic Mycoplasma spp., Hepatozoon spp., Leishmania infantum , piroplasms and microfilariae at the LABOKLIN laboratory. The cats were also tested for FeLV and FIV by PCR. Results Nearly half of the cats (158/332, 47.6%) were positive for at least one VBP. Hepatozoon spp. were detected in 25.6%, haemotropic Mycoplasma spp. in 22.9%, B. henselae in 9.3% and L. infantum in 2.1% of the cats. Male sex had a statistically significant association with test results for haemotropic Mycoplasma spp. (odds ratio 1.38 [1.21;1.57]); regionality with Hepatozoon spp., B. henseale and FIV; and seasonality with Hepatozoon spp., haemotropic Mycoplasma spp., L. infantum and FeLV ( P ≤ 0.05 each). A strong positive correlation was reported for the amount of rainfall and the number of cats that tested positive for Hepatozoon spp. ( ρ = 753, P = 0.05). None of the cats tested positive for A. phagocytophilum , A. platys , E. canis , Rickettsia spp., piroplasms, or microfilariae. Co-infections with multiple VBPs were detected in 56 out of 332 cats (16.9%). Thirty-one of the 332 cats included in the study (9.3%) tested positive for FeLV (6.9%) and for FIV (3.6%). In 20/31 cats (64.5%) that tested positive for FeLV/FIV, coinfections with VBP were detected ( P = 0.048, OR 2.15 [0.99; 4.64]). Conclusions VBPs were frequently detected in stray cats in Zaragoza. In particular, regionality and seasonality had a statistically significant association with PCR results for most VBPs included in the study. Graphical Abstract