Serological Evidence of Rickettsia spp. in Western Australian Dogs

It has been claimed that dogs can be useful sentinels for public health monitoring of vector-borne infectious diseases, including Rickettsia spp. We used 153 canine blood samples opportunistically collected at Murdoch University Veterinary Hospital and 156 canine sera collected from Aboriginal communities in northwest Western Australia to test for evidence of Rickettsia spp. exposure, using microimmunofluorescence (MIF) in the latter case, and both MIF and polymerase chain reaction (PCR) in the former. Conventional and real-time PCR failed to amplify any Rickettsia spp. DNA. The seroprevalence for spotted fever group/transitional group Rickettsia spp. in Western Australian dogs was 17.3% (54/312), and for typhus group (TG) Rickettsia spp., 18.4% (57/310), with a cut-off titer of 1:128. Young dogs (≤ 2 years) from Aboriginal communities had significantly lower seropositivity to TG Rickettsia spp. compared with all other groups, and young Perth dogs had a significantly higher seropositivity to TG Rickettsia spp. than all Aboriginal community dogs.