A CDC analysis of the initial cases leading to 26 tuberculosis (TB) outbreaks in the U.S. found many common characteristics among the source patients, including long infectious periods and several social risk factors. Specifically, source patients were mostly U.S.-born men and many had infectious periods lasting 10 months or longer, which is concerning because TB can spread to others and be fatal if not properly diagnosed and treated.
Most reported substance abuse, half were incarcerated at some point previously, and nearly half were homeless in the year before diagnosis. These findings underscore the importance of timely diagnosis of TB cases and thorough efforts to identify contacts of those individuals in order to help reduce the risk for further transmission, especially among marginalized populations. Given the continued decline of TB in the U.S., it is also critical that providers remain alert for symptomatic patients to avoid later-stage diagnosis.
Characteristics of Tuberculosis Cases that Started Outbreaks in the United States, 2002-2011, Maryam B. Haddad, Kiren Mitruka, John E. Oeltmann, Emma B. Johns, Thomas R. Navin, Emerging Infectious Diseases, DOI: 10.3201/eid2103.141475, published online 11 February 2015.