A unique Russian report indicated that three different strains of M. tuberculosis, including the H37Rv strain studied
herein, could be cultured for no longer than 3 months after being seeded in natural turf–podzol sandy soil (Kozlov & Rotov, 1977). Several reports have indicated that M. bovis is able to survive in soil (Walter et al., 2012). One previous study, using PCR-based detection, found mpb64 and mpb70 MTC-specific sequences in soil sampled from an Irish farm that had a history of bovine tuberculosis, and no incoming infected bovines and badgers after culling, for as long as 15 months after possible contamination. The sequences exhibited .99% identity to reference M. bovis sequences (Young et al., 2005). Nevertheless, experimental inoculation of other farm soil with the M. bovis BCG Pasteur strain revealed a rapid decrease in both living cells and DNA content, and the influence of both temperature and humidity in such decay processes (Young et al., 2005).