Tuberculosis is a chronic, communicable disease caused principally by M. TB hominis (Koch’s bacillus) and occasionally by M. TB bovis. The risk of TB infection exponentially declined in the 20th century. However, the recent emergence of drug-resistant strains has rekindled interest in TB. The incidence of infection was reported to be around 8 million cases per year with a death rate of 3 million per year. Serological detection of IgM indicates a fresh M. TB infection, while an IgG positive result suggests a previous or chronic infection.