A statement from the U.S. Preventive Services Task Force (USPSTF) recommends screening for latent tuberculosis infection in populations at increased risk for this important preventable disease.
The document, published Tuesday in JAMA Network, was based on a systematic review designed to update USPSTF’s 2016 recommendations.
Tuberculosis includes active tuberculosis, which may be infectious, and latent tuberculosis infection (LTBI), which is asymptomatic and not infectious, but can progress to active disease. The prevalence rate of LTBI in the U.S. is estimated at about 5%, or up to 13 million persons.
Tuberculosis is spread through respiratory transmission. Approximately 30% of persons exposed to Mycobacterium tuberculosis will develop LTBI and, if left untreated, approximately 5% to 10% will progress to active tuberculosis. The disease disproportionately affects certain U.S. populations, including Asian, Black, Hispanic, Native American, and Native Hawaiian/Pacific Islanders.
Tuberculosis incidence varies by geography and living accommodations, suggesting an association with social determinants of health. Populations at increased risk for LTBI include persons who were born in or are former residents of countries with high tuberculosis rates, and persons who live in, or have lived in, high-risk congregate settings, including homeless shelters and correctional facilities. An effective strategy for reducing the transmission, morbidity, and mortality of active tuberculosis is the identification and treatment of LTBI.
The USPSTF commissioned a review on LTBI screening and treatment in asymptomatic adults at increased risk for tuberculosis, as well as the accuracy of LTBI screening tests. They found that available tests — in particular, the tuberculin skin test and interferon-γ release assays — were sufficiently accurate to identify persons with LTBI who might benefit from treatment to prevent progression to active tuberculosis. They concluded that recommended TB preventive treatment (TPT) regimens provide moderate net benefits to persons identified via screening.
However, to achieve screening’s full benefits, they note the importance of follow-up and treatment for persons who screen positive for LTBI, including offering TPT to all who are eligible, and education, counseling, and subsequent monitoring for those who accept TPT, to ensure adherence as well as to detect and manage any adverse effects.
A related editorial published on Thursday in JAMA Network Open by Dr. Dick Menzies, director of the McGill International TB Centre, recommends that the screening of this large and otherwise healthy population be shifted from public clinics to primary care — an underutilized sector for TB prevention in the U.S. He notes that this would require a paradigm shift.
Dr. Menzies said that he believes successful implementation of LTBI screening in primary care requires three things: simple, accurate screening tests; short, simple, and safe TPT; and cost reimbursement. Evidence is needed that these requirements are feasible and that retention of individuals would be high throughout the LTBI cascade of care, from initial identification, screening, evaluation, and initiation, to TPT completion.
“In this way, the full benefits of LTBI screening will be realized for individuals and the long-term goal of TB elimination in the U.S. may be achieved,” Dr. Menzies writes.
