The number of tuberculosis (TB) cases in the United States climbed in 2023, the third straight year of increases, according to new data from the Centers for Disease Control and Prevention (CDC).
The data, published yesterday in Morbidity and Mortality Weekly Report, show that 9,615 TB cases were reported in the United States in 2023, a 16% increase from 2022 and the highest number reported since 2013. The TB incidence rate of 2.9 cases per 100,000 persons represented a 15% increase from 2022. TB incidence increased in every age-group, with the largest increase seen in children ages 5 to 14 years.
As in previous years, most reported TB cases in 2023 (76%) occurred in non–US-born residents. But case counts rose among both US-born and non–US-born residents, who saw increases of 9% and 18%, respectively. Among US-born persons with TB, 33% were Black, 27% Hispanic, 26% White, 6% Asian, 5% American Indian or Native Alaskan, and 3% Native Hawaiian or other Pacific Islander.
Despite the rise in cases and incidence, the United States still has one of the lowest TB rates in the world, and most US residents are at minimal risk of infection. CDC researchers note that roughly 85% of US TB cases are attributed to reactivation of latent TB infection—in which people are infected with Mycobacterium tuberculosis but have no symptoms—rather than recent transmission.
"Therefore, sustained transmission of TB in the United States leading to outbreaks is uncommon," they wrote.
The impact of the COVID-19 pandemic
The CDC says the increase may be related to COVID-19 pandemic–related disruptions to TB services. As was seen in other countries, the pandemic diverted resources and staff from TB programs to COVID response, and timely TB diagnosis and treatment suffered as a result. Cases missed in 2020 then started showing up in subsequent years.
"These factors, along with changes in migration volume, probably contributed to the decrease in the number of cases observed in 2020, and to the subsequent rise in case counts and rates since 2020," the researchers wrote. "Identification of TB cases possibly increased after the pandemic because of renewed attention to infectious diseases other than COVID-19."
Prior to the pandemic, TB incidence in the United States had been steadily declining since 1992.
The CDC says renewed progress toward TB elimination will require strengthened public health systems to carry out TB control and prevention strategies both domestically and globally.
Identification of TB cases possibly increased after the pandemic because of renewed attention to infectious diseases other than COVID-19.