Serological screening of Coxiella burnetii (Q fever) and Brucella spp. in sheep flocks in the northern prefectures of Japan in 2007

Ovine sera collected from the northern Prefectures of Hokkaido, Iwate and Aomori in Japan, were examined for the presence of antibodies against Coxiella burnetii (Q fever) using the complement fixation test and, against Brucella spp., using both the rapid serum agglutination test and the complement fixation test. None of the sera tested were serologically positive to Brucella spp. A total of 21 animals (8.64%) out of 243 samples tested were seropositive to the C. burnetii antigen. Levels of infection were observed in all of the three Prefectures and in ten flocks of the fourteen sampled. Although no diagnostic measures were in place, the infection could not be linked to losses in sheep production or to the decreased fertility in ewes, a lower lambing rate and mortality in lambs. These data confirmed that Q fever is widespread in the sheep population in the area studied. Considering the zoonotic potential of the disease, further studies to investigate the epidemiology of Q fever in this region are required.