Tuberculosis and Substance Abuse in the United States, 1997-2006

Substance abuse is the most commonly reported behavioral risk factor among patients with TB in the United States. Patients who abuse substances are more contagious (eg, smear positive) and remain contagious longer because treatment failure presumably extends periods of infectiousness. Increased transmission is consistent with our finding that patients who abuse substances were more likely to be involved in a localized genotype cluster, which can represent recent transmission.[ Arch Intern Med. 2009;169(2):189-197.]