Surveillance of Bovine Tuberculosis and Risk Estimation of a Future Reservoir Formation in Wildlife in Switzerland and Liechtenstein
Open Access
- 21 January 2013
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 8 (1), e54253
- https://doi.org/10.1371/journal.pone.0054253
Abstract
Bovine tuberculosis (bTB) caused by Mycobacterium bovis or M. caprae has recently (re-) emerged in livestock and wildlife in all countries bordering Switzerland (CH) and the Principality of Liechtenstein (FL). Comprehensive data for Swiss and Liechtenstein wildlife are not available so far, although two native species, wild boar (Sus scrofa) and red deer (Cervus elaphus elaphus), act as bTB reservoirs elsewhere in continental Europe. Our aims were (1) to assess the occurrence of bTB in these wild ungulates in CH/FL and to reinforce scanning surveillance in all wild mammals; (2) to evaluate the risk of a future bTB reservoir formation in wild boar and red deer in CH/FL. Tissue samples collected from 2009 to 2011 from 434 hunted red deer and wild boar and from eight diseased ungulates with tuberculosis-like lesions were tested by direct real-time PCR and culture to detect mycobacteria of the Mycobacterium tuberculosis complex (MTBC). Identification of suspicious colonies was attempted by real-time PCR, genotyping and spoligotyping. Information on risk factors for bTB maintenance within wildlife populations was retrieved from the literature and the situation regarding identified factors was assessed for our study areas. Mycobacteria of the MTBC were detected in six out of 165 wild boar (3.6%; 95% CI: 1.4–7.8) but none of the 269 red deer (0%; 0–1.4). M. microti was identified in two MTBC-positive wild boar, while species identification remained unsuccessful in four cases. Main risk factors for bTB maintenance worldwide, including different causes of aggregation often resulting from intensive wildlife management, are largely absent in CH and FL. In conclusion, M. bovis and M. caprae were not detected but we report for the first time MTBC mycobacteria in Swiss wild boar. Present conditions seem unfavorable for a reservoir emergence, nevertheless increasing population numbers of wild ungulates and offal consumption may represent a risk.This publication has 95 references indexed in Scilit:
- Bovine viral diarrhea virus in free-ranging wild ruminants in Switzerland: low prevalence of infection despite regular interactions with domestic livestockBMC Veterinary Research, 2012
- Risk factors for contacts between wild boar and outdoor pigs in Switzerland and investigations on potential Brucella suis spill-overBMC Veterinary Research, 2012
- Evaluation of Cobas TaqMan MTB PCR for Detection of Mycobacterium tuberculosisJournal of Clinical Microbiology, 2011
- Lesion Distribution and Epidemiology ofMycobacterium bovisin Elk and White-Tailed Deer in South-Western Manitoba, CanadaVeterinary Medicine International, 2011
- Preventing the Establishment of a Wildlife Disease Reservoir: A Case Study of Bovine Tuberculosis in Wild Deer in Minnesota, USAVeterinary Medicine International, 2011
- Mycobacterium microti : More Diverse than Previously ThoughtJournal of Clinical Microbiology, 2009
- The importance of parasite life history and host density in predicting the impact of infections in red deerOecologia, 2007
- Bovine tuberculosis in African buffaloes: observations regarding Mycobacterium bovis shedding into water and exposure to environmental mycobacteriaBMC Veterinary Research, 2007
- Estimation of European wild boar relative abundance and aggregation: a novel method in epidemiological risk assessmentEpidemiology and Infection, 2006
- Herd-level risk factors associated with tuberculosis breakdowns among cattle herds in England before the 2001 foot‐and‐mouth disease epidemicBiology Letters, 2005