CDC Morbidity and Mortality Weekly Report (MMWR) January 1, 2016: “Although the number of TB cases in 44 states and Puerto Rico and the percentage of index patients with no contacts elicited declined from 2003 to 2012, the percentage of contacts who were examined did not change, and fewer than half of contacts who received a diagnosis of LTBI completed treatment. In 2012, contacts outnumbered TB cases almost 11 to 1 in the United States, which indicates a burden of public health work that is not evident from TB case counts alone, and is thus not apparent to the public or to policy makers. TB contact investigations are complex interventions, lasting more than 2 years and requiring specialized skills. For example, after public health authorities assess the contagious period of an index TB patient, a list of contacts is elicited by 1) interviewing the index patient or proxies, 2) reviewing administrative records in congregate settings (e.g., schools), and 3) visiting sites frequented by the index patient. The procedures required to confirm TB disease or LTBI can take up to 3 months. The most common regimen for treating LTBI has been daily isoniazid for 9 months, with monthly health care visits for monitoring treatment…”