Submitted to: BioMed Central (BMC) Veterinary Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 21, 2013
Publication Date: May 8, 2013
Repository URL: http://handle.nal.usda.gov/10113/56527
Citation: Thacker, T.C., Robbe-Austerman, S., Harris, B., Palmer, M.V., Waters, W.R. 2013. Isolation of Mycobacteria from clinical samples collected in the United States from 2004 to 2011. BioMed Central (BMC) Veterinary Research. 9(1):100. Interpretive Summary: Mycobacterium bovis causes tuberculosis in humans, cattle and deer. Mycobacteria other than Mycobacterium bovis are found in the environment and can infect animals. When these environmental mycobacteria infect an animal they can interfere with current diagnostic tests making them less effective. The interference from environmental mycobacteria becomes greater as the number of animals with tuberculosis decreases, resulting in more false positive test results. To improve current diagnostic tests and develop new tests, it is critical to identify the mycobacteria that are infecting cattle and deer. Here we report the mycobacteria that are grown from animal samples that were suspected of having tuberculosis. These results will be used to compare the genomes of the environmental mycobacteria with Mycobacterium bovis to identify proteins or genes that can be used to improve the current diagnostic tests and to develop new tests.
Technical Abstract: Background: Mycobacteria other than M. bovis (i.e. atypical mycobacteria) may interfere with current bovine tuberculosis diagnostic tests resulting in false positive test results. In populations with low prevalence of M. bovis (i.e., as detected within the United States), interference from atypical mycobacteria play an increasingly important role in preventing the eradication of M. bovis. To help characterize the atypical mycobacteria that may be interfering with current diagnostic tests, mycobacteria isolated from clinical tissues at the National Veterinary Services Laboratories were speciated, enumerated and compared by season, host species, region, and type of submission (i.e., field vs abattoir surveillance). Results: Between 1 January 2004 and 9 October 2001, 2,366 atypical mycobacteria were isolated from samples submitted for clinical diagnosis of M. bovis. Fifty-five mycobacterial species were isolated during this time period. In cattle, M. avium complex, M. fortuitum/fortuitum complex, M. smegmatis, M. kansasii, and M. terrea complex were the predominate species other than M. bovis isolated from tissues submitted for culture. Mycobacteria other then M. bovis isolated from deer were predominantly M. avium complex, M. terrae/terrae complex, and M. fortuitum/fortuitum complex. Conclusions: These data provide information characterizing the mycobacterial species and relative prevalence of atypical mycobacteria that may be interfering with current diagnostic tests.