Prevalence ofspp. Infection in Ticks Collected from Shelter Dogs in Tulcea County, Romania.

Abstract

Ticks are one of the most important vectors of zoonotic pathogens in Europe, includingspp. In Romania, several pathogenic species belonging to the Spotted Fever Group (SFG) transmitted primarily through tick bites have been identified. The aim of the present study was to determine the prevalence ofspp. infection in ticks collected from public shelter dogs in Tulcea County, Romania, as an indicator of pathogen circulation within shelter environments and their potential epidemiological relevance. A total of 730 ticks collected between March 2023 and September 2024 from 216 public shelter dogs, belonging to four species (s.l.,,, and), were morphologically identified and pooled by species, sex, and developmental stage resulting in 132 pools. DNA extracted from pools was tested by Real-Time PCR, targeting thegene, specific forspp. Overall, 123/132 (93.2%) pools tested positive forspp. DNA, while the Minimum Infection Rate (MIR) at tick level was 16.8%. High pool positivity rates were consistently observed across all four species: 93.6% positive pools fors.l. (MIR 15%), 88.2% for(MIR 20.5%), 87.5% for(MIR 58.3%), and 100% for(MIR 21.7%). These findings demonstrate a substantial circulation ofspp. in dog-shelter associated ticks, highlighting the role of dogs as sentinel hosts. Continuous molecular surveillance and identifying circulating species is needed for a better determination of the zoonotic risk.