A SEROSURVEY FOR BRUCELLA SPP. AND MYCOBACTERIUM TUBERCULOSIS COMPLEX PREVALENCE IN HUNTED WILD BOAR IN CAMPANIA REGION

Bovine tuberculosis bTB, caused by Mycobacterium bovis and related members of the mycobacterium tuberculosis complex (MTBC) as well Brucellosis are zoonotic diseases undergoing to specific eradication plans worldwide. In Italy the eradication process has led to the eradication of bTB and Brucellosis in several regions, however, it is still present in livestock in Campania region. Both diseases are frequently reported among wildlife populations in Europe and particularly in the Eurasian wild boar which population is in a progressive expansions throughout Europe in the last decades, raising concerns regarding the control of diseases in this species. In fact, in the last decade, a growing attention has been paid to the role that wild animals can have in the epidemiology of tuberculosis and particularly to Eurasian wild boar. Thus, in the present study we carried out a cross-sectional survey in wild boars in Campania region to assess the sero-prevalence against Brucella spp and Mycobacterium bovis or cross-reacting members of the MTBC and to provide information on associated risk factors using an enzyme linked immunosorbent assays developed using MPB83-antigen for MTBC and Rose Bengal Test (RBT) and a competitive enzyme-linked immunosorbent assay form Brucella spp. Fifty-six out of 513 (10.92%; 95% CI: 19.47-2.36%) sampled animals presented antibodies against M. bovis in MPB83-ELISA. Statistical analysis indicated that the sero-positivity to M. bovis was not associated with age, sex or location of sampling. We also evaluated the correlation between the sero-positivity in wild boar and the presence of tuberculosis outbreaks in livestock. The mean distance from a TB outbreak for the seropositive subjects ranged from 0 to 20 km (mean 7.38 km). Our results showed that exposure of wild boar to MTC is consistent with TB outbreaks in cattle, in fact, the mean distance between a seropositive wild boar and the nearest cattle outbreak was 7.38 km which is compatible with the daily movement capacities of a wild boar (1 - 16 km). Furthermore, or results demonstrated an apparent brucellosis prevalence of 11.31% (95% CI 2.61-20.00%). Brucellosis prevalence was significantly affected by the region of sampling but not by age or by sex of the animals. The relative sensitivity of the Rose Bengal test (RBT) versus the cELISA was 8.6% while the relative specificity was 96%. In conclusion, the sero-prevalences observed in the present study indicates a wide exposure to MTBC and Brucella in wild boar in Campania region, which may have important implications not only for conservation but also for animal and public health and could represent a growing risk of spillback to outdoor-farmed herds. However, further investigations are needed using bacterial isolation as well as PCR, to better characterize the responsible Brucella and Mycobacterium involved.