U.S. health care personnel no longer need to undergo routine tuberculosis testing in the absence of known exposure, according to new screening guidelines from the National Tuberculosis Controllers Association and CDC.

The revised guidelines on tuberculosis screening, testing, and treatment of U.S. health care personnel, published in Morbidity and Mortality Weekly Report, are the first update since 2005. The new recommendations reflect a reduction in concern about U.S. health care personnel’s risk of occupational exposure to latent and active tuberculosis infection.

Lynn E. Sosa, MD, from the Connecticut Department of Public Health and National Tuberculosis Controllers Association, and coauthors wrote that rates of tuberculosis infection in the United States have declined by 73% since 1991, from 10.4/100,000 population in 1991 to 2.8/100,000 in 2017. This has been matched by similar declines among health care workers, which the authors said raised questions about the cost-effectiveness of the previously recommended routine serial occupational testing.

“In addition, a recent retrospective cohort study of approximately 40,000 health care personnel at a tertiary U.S. medical center in a low TB-incidence state found an extremely low rate of TST conversion (0.3%) during 1998-2014, with a limited proportion attributable to occupational exposure,” they wrote.

The new guidelines recommend health care personnel undergo baseline or preplacement tuberculosis testing with an interferon-gamma release assay (IGRA) or a tuberculin skin test (TST), as well as individual risk assessment and symptom evaluation.

The individual risk assessment considers whether the person has lived in a country with a high tuberculosis rate, whether they are immunosuppressed, or whether they have had close contact with someone with infectious tuberculosis.

This risk assessment can help decide how to interpret an initial positive test result, the authors said.

“For example, health care personnel with a positive test who are asymptomatic, unlikely to be infected with M. [Mycobacterium] tuberculosis, and at low risk for progression on the basis of their risk assessment should have a second test (either an IGRA or a TST) as recommended in the 2017 TB diagnostic guidelines of the American Thoracic Society, Infectious Diseases Society of America, and CDC,” they wrote. “In this example, the health care personnel should be considered infected with M. tuberculosis only if both the first and second tests are positive.”

After that baseline testing, personnel do not need to undergo routine serial testing except in the case of known exposure or ongoing transmission. The guideline authors suggested serial screening might be considered for health care workers whose work puts them at greater risk – for example, pulmonologists or respiratory therapists – or for those working in settings in which transmission has happened in the past.

For personnel with latent tuberculosis infection, the guidelines recommend “encouragement of treatment” unless it is contraindicated, and annual symptom screening in those not undergoing treatment.

The guideline committee also advocated for annual tuberculosis education for all health care workers.

The new recommendations were based on a systematic review of 36 studies of tuberculosis screening and testing among health care personnel, 16 of which were performed in the United States, and all but two of which were conducted in a hospital setting.

The authors stressed that recommendations from the 2005 CDC guidelines – which do not pertain to health care personnel screening, testing, treatment and education – remain unchanged.

One author declared personal fees from the National Tuberculosis Controllers Association during the conduct of the study. Two others reported unrelated grants and personal fees from private industry. No other conflicts of interest were disclosed.

SOURCE: Sosa L et al. MMWR. 2019;68:439-43.

New recommendations on TB screening for health care workers