Routine annual tuberculosis testing may be on the way out, following a new recommendation published in the Center for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.
The report, a culmination of extensive research, reveals that tuberculosis (TB) rates have become so rare among healthcare workers that it may not be worth the time and expense to conduct routine testing.
“We were doing, as a country, tens of millions of TB tests annually on a population that doesn’t have TB,” explains Wendy Thanassi, MD, MA, chief of occupational health at VA Palo Alto, associate professor at Stanford University, and co-author of the guidance.
Thanassi and several other authors who worked on the guidance presented their findings and answered questions about their research at the Association of Occupational Health Professionals (AOHP) National Conference Sept. 4-7 in Baltimore, Md.
Routine TB testing stems from the century-old fear of the infection, which—thanks to successful public health programs in the United States—no longer appears to be warranted, she says.
“Tuberculosis is still an incredibly dangerous infection. In the United States, it was the leading cause of death in 1915-16,” Thanassi says. “But in the last 100 years, there has been incredible progress in treatment and environmental controls.”
Nutrition and living conditions have improved to the point that the United States now has one of the lowest rates of TB infection at about 2.8 cases per 100,000 individuals—lower in healthcare workers at approximately 2.5/100,000. This represents a 73 percent decrease in TB prevalence from 1991 to 2017—and a 42 percent drop from 2005 to 2017, according to the report.
With roughly 18 million healthcare workers in the United States, Thanassi says the healthcare cost—as well as the environmental cost related to unnecessary transportation of testing supplies and medical waste—is huge.
“When I look at the sweeping change this can make—we are saving tons of medical waste per year,” Thanassi says. “It all came together to mean we have to stop doing these tests every year on healthcare workers. It doesn’t make sense to do tens of millions of tests looking at the population where TB isn’t.”
The research contained in the MMWR report was based initially on more than 1,800 studies conducted since the last guidance on TB testing in healthcare workers was drafted in 2005. The final report was focused on 36 of the most relevant studies, all of which pointed to the conclusion that routine TB testing of healthcare workers is no longer needed. In fact, prevalence of TB among healthcare workers was so low in the data that Thanassi says workers were more likely to have a false positive result than a true positive one.
Thanassi says extensive databases developed over the last decade enabled this level of research and estimates that 96.6 percent of TB tests on the VA’s own 400,000 healthcare workers test negative on annual screening negative. She said the new recommendation means that public health efforts can now be turned to more at-risk populations.
“We want to divert the focus and spending to treating latent TB in the United States and focus our energies on those who still suffer from this disease,” Thanassi says.
Not all states or all healthcare facilities require annual TB screening for healthcare workers, and even some that do have considered discontinuing the practice, Thanassi says.
This report may give those states and institutions the data they need to support a policy change—although the decision to stop routine TB testing ultimately will be made at the individual healthcare facility level. California is one state that has debated abandoning routine TB testing for healthcare workers, considering the 1.4 million healthcare workers in the state, just 92 cases of TB were identified in 2016. The healthcare savings and positive environmental impact of such a change could be monumental, she says.
A companion report on risk assessments and facility-level recommendations that is forthcoming, and will be published in the Journal of Occupational Health and Environmental Medicine.
Thanassi was also clear that the recommendation in MMWR does not impact post-exposure TB testing for healthcare workers, a practice that she said should continue without question. Routine pre-employment testing of healthcare workers for TB, as well as testing and treatment of workers with TB, also should be continued, according to the report.