We have identified a globally important clonal complex of M. bovis by deletion analysis of over one thousand strains from over 30 countries. We initially show that over 99% of the strains of Mycobacterium bovis, the cause of bovine tuberculosis, isolated from cattle in the Republic of Ireland and the UK are closely related and are members of a single clonal complex marked by the deletion of chromosomal region RDEu,1 and we named this clonal complex European 1 (Eu1). Eu1 strains were present at less than

Captive and free-ranging wildlife animals are implicated in the maintenance and transmission of bovine tuberculosis and therefore pose a significant obstacle to eradication of the disease from domestic livestock. The current antemortem diagnostic method, the intradermal tuberculin skin test, is impractical for routine use with many wild animals. Antibody-based assays are particularly attractive because the animals are handled only once and immediate processing of the sample is not required. This report characterizes the antibody responses of red deer-elk hybrids (Cervus elaphus) against Mycobacterium bovis and subsequently evaluates the diagnostic performance of select antigens in a rapid-test format. Sequential serum samples were collected from 10 animals experimentally infected with M. bovis and 5 noninfected animals over a 7-month period postinfection (p.i.). Samples were evaluated by enzyme-linked immunosorbent assays, immunoblot analyses, and multiantigen print immunoassays for seroreactivity to mycobacterial antigens. Although all infected animals produced antibodies to M. bovis protein antigens, there was significant animal-to-animal variation in the kinetics and magnitudes of responses and the antigens recognized. The most frequently recognized antigens included MPB83, ESAT-6, CFP10, and MPB70. Responses to some antigens, such as MPB83, were consistently detected as early as 4 weeks after inoculation, whereas other antigens were detected only much later (>140 days p.i.). Antibody responses were boosted by injection of tuberculin for intradermal tuberculin skin testing. Comparison of single-antigen (fluorescence polarization assay) with multiantigen (CervidTB STAT-PAK) rapid tests demonstrated that a highly sensitive and specific serodiagnostic test for tuberculosis in cervids will require multiple and carefully selected seroreactive antigens covering a broad spectrum of antibody specificities.Mycobacterium bovis, the etiological agent of bovine tuberculosis (TB), has an extraordinarily broad mammalian host range that includes humans, domestic livestock, and wildlife. Globally, several wildlife species have been implicated in the maintenance and transmission of M. bovis. In North America, these include white-tailed deer (Odocoileus virginianus) in northeastern Michigan (37), elk (Cervus elaphus) in and around Riding Mountain National Park, Manitoba, Canada (31), and wood bison (Bison bison athabascae) in and around Wood Buffalo National Park, Alberta, Canada, and the Northwest Territories (31). The continued transmission of M. bovis from free-ranging wildlife reservoirs to domestic livestock results in significant economic losses and is a significant barrier to the success of national eradication and control programs (5). Similarly, TB agent-infected captive wildlife maintained in farms or animal parks (e.g., zoos or game farms) may also serve as foci of infection for domestic animals, free-ranging wildlife, and humans (7, 42). The existing methods for diagnosing bovine TB that rely on cell-mediated immun...