Molecular Prevalence of Zoonotic Pathogens in Pet and Stray Dogs in Southern Taiwan

Abstract

The prevalence of important zoonotic diseases including Lyme disease, Q fever, heartworm disease, leptospirosis and toxoplasmosis in pet and stray dogs in southern Taiwan (Kaohsiung City and Pingtung County) was assessed using nested, semi-nested or traditional polymerase chain reaction. The correlations between the prevalence and regional demiographic data were also analyzed. Blood samples were randomly collected from pet and stray dogs monthly from September 2009 to August 2011. The PCR sensitivity for Borrelia burgdorferi was 10 pg, 100 fg for Coxiella burnetii, 1 pg for Dirofilaria immitis, 100 pg for Leptospira spp. and 10 fg for Toxoplasma gondii, respectively, in 0.8~1.5 g total DNA from the blood sample. No cross-reaction was observed between the nucleic acids of interest and DNA extracted from Ehrlichia canis, Babesia canis and Babesia gibsoni for the selected PCR primers. The 5 zoonotic pathogens and their prevalence rates in dogs were B. burgdorferi 0.07% (1/1440), C. burnetii 4.79% (69/1440), D. immitis 7.08% (102/1440), Leptospira spp. 0.07 % (1/1440) and T. gondii 0.14% (2/1440), which highlights the importance of C. burnetii and D. immitis among dogs in southern Taiwan. Further analysis between the prevalence and associated epidemiological factors demonstrated that prevalence of C. burnetii is correlated with the season, age and source (pet or stray) but not breed and gender. The prevalence of D. immitis was relevant to age and source but not with season, breed or gender. Overall, this study reveals hygienic implications as seen with the prevalence of Q fever and heartworm disease and raises public health awareness in southern Taiwan as well as the neighboring areas and countries.