Prospects for Tuberculosis Elimination in the United States: Results of a Transmission Dynamic Model

Abstract

We estimated long-term tuberculosis (TB) trends in the US population and assessed prospects for TB elimination. We used a detailed simulation model allowing for changes in TB transmission, immigration, and other TB risk determinants. Five hypothetical scenarios were evaluated from 2017 to 2100: 1) maintain current TB prevention and treatment activities (base case); 2) provision of latent TB infection testing and treatment for new legal immigrants; 3) increased uptake of latent TB infection screening and treatment among high-risk populations, including a 3-month isoniazid-rifapentine regimen; 4) improved TB case detection; and 5) improved TB treatment quality. Under the base case, we estimate that by 2050, TB incidence will decline to 14 cases per million, a 52% (95% posterior interval (PI): 35, 67) reduction from 2016, and 82% (95% posterior interval: 78, 86) of incident TB will be among persons born outside of the United States. Intensified TB control could reduce incidence by 77% (95% posterior interval: 66, 85) by 2050. We predict TB may be eliminated in US-born but not non-US-born persons by 2100. Results were sensitive to numbers of people entering the United States with latent or active TB, and were robust to alternative interpretations of epidemiologic evidence. TB elimination in the United States remains a distant goal; however, strengthening TB prevention and treatment could produce important health benefits.

Tuberculosis — United States, 2018

“…CDC also recommends testing for TB in health care workers and others who work in places where there is a high risk of TB transmission, persons who are contacts of a person with infectious TB disease, and immunocompromised persons, who have a higher risk for developing TB disease once infected . According to one model, increased uptake of LTBI screening and treatment among populations at higher risk for TB would result in an incidence of 26 new infections per million by 2050 . Detection of LTBI can be improved by the preferential use of interferon‐γ release assays over the tuberculin skin test, especially in persons with a history of Bacillus Calmette‐Guérin vaccination or who are unlikely to return to have their tuberculin skin test read .…”

“…This report summarizes provisional TB surveillance data reported to CDC's National Tuberculosis Surveillance System (NTSS) through 2018. Although the total number of cases and incidence are the lowest ever reported in the United States, a recent model predicted that the U.S. TB elimination goal (annual incidence of <1 case per 1 million persons) will not be attained in the 21st century without greatly increased investment in detection and treatment of latent TB infection (LTBI) . Programs to identify, test, and treat populations at high risk for TB remain important to eliminating TB in the United States.…”

Latent tuberculosis infection: recent progress and challenges in South Korea

“…Multiple modeling studies have consistently suggested the solution to this critical question. TB elimination can be achieved through comprehensive strategies directed toward integrated LTBI management with proper active TB management [5,6]. Programmatic management of LTBI is emerging as a critical component of TB control programs for TB elimination [7].…”

Capturing heterogeneous infectiousness in transmission dynamic models of tuberculosis: a compartmental modelling approach

“…This approach implies that all pulmonary TB patients are equally infectious, while all extrapulmonary patients are entirely non-infectious, and so does not capture the heterogeneity among pulmonary patients. Other TB models have considered sputum smear status as a factor in stratifying patients' levels of infectiousness, considering both smear-negative and smearpositive pulmonary TB to be infectious, with the relative infectiousness of smear-negative patients compared to smear-positive typically set between 15 and 25% [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. While stratifying pulmonary TB patients based on smear status captures an additional clinical attribute that is important in determining infectiousness, even these models still do not capture the full picture of TB patients' infectiousness variation, since several behavioural and demographic factors other than smear status can affect the level of infectiousness [5].…”