Shiloh
Editor, Senior Moderator
Source: https://www.cdc.gov/mmwr/volumes/75/wr/mm7516a1.htm
Large Tuberculosis Outbreaks — United States, 2017–2023
Weekly / April 30, 2026 / 75(16);205–210
Kala M. Raz, MPH[SUP]1[/SUP]; Maryam B. Haddad, PhD[SUP]1[/SUP]; Sandy P. Althomsons, MA, MHS[SUP]1[/SUP]; Lauren Cowan, PhD[SUP]1[/SUP]; J. Steve Kammerer, MBA[SUP]1[/SUP]; Chee Kin Lam, MS, MPH[SUP]1[/SUP]; Clinton J. McDaniel, MPH[SUP]1[/SUP]; James Posey, PhD[SUP]1[/SUP]; Sarah Talarico, PhD[SUP]1[/SUP]; William L. Walker, DVM, PhD[SUP]1[/SUP]; Noah G. Schwartz, MD[SUP]1,[/SUP]*; Jonathan M. Wortham, MD[SUP]1,[/SUP]* (View author affiliations)
Summary
What is already known about this topic?
During 2014–2016, a total of 24 large tuberculosis (TB) outbreaks (10 or more related TB cases within a 3-year period) were identified within the United States, primarily affecting U.S.-born persons.
What is added by this report?
During 2017–2023, a total of 50 large TB outbreaks were identified in 23 states, primarily involving U.S.-born persons. Persons with TB in large outbreaks reported substance use, homelessness, and incarceration more often than did other persons with TB. Two thirds of large outbreaks occurred within family and social networks.
What are the implications for public health practice?
Nationwide capacity for outbreak detection, prevention, and response is critical for reducing outbreak-associated morbidity. Building trust within affected communities and overcoming barriers to diagnosis and treatment associated with homelessness and substance use are critical for outbreak prevention.
Related Materials
Abstract
During 2017–2023, based on an analysis of national genomic and tuberculosis (TB) case surveillance data, 50 large TB outbreaks (10 or more related TB cases in a 3-year period) involving 1,092 cases were identified in 23 states. Compared with 61,993 other persons who received a diagnosis of TB during this period, persons included in large outbreaks were more frequently U.S.-born (79% versus 26%), and a higher percentage reported substance use (27% versus 12%), homelessness (9% versus 5%), and incarceration (11% versus 3%). Approximately one fourth of these large outbreak-related cases were identified through contact tracing; these cases less commonly had clinical markers of highly infectious disease (23%) than did large outbreak-related cases identified through other methods (including evaluation associated with symptoms, targeted testing, or incidental findings) (61%), suggesting that contact tracing might have facilitated earlier diagnosis. Among the 50 large outbreaks, 34 (68%) were primarily associated with family or social networks, and 13 (26%) were primarily associated with congregate settings. Maintaining state and local public health capacity for outbreak detection, prevention, and response is essential, even in low-incidence jurisdictions. Effective outbreak responses must overcome barriers to diagnosis and treatment associated with homelessness and substance use and include efforts to build trust with affected communities. Procedures to promptly identify and isolate persons with infectious TB remain critical in congregate settings...
Large Tuberculosis Outbreaks — United States, 2017–2023
Weekly / April 30, 2026 / 75(16);205–210
Kala M. Raz, MPH[SUP]1[/SUP]; Maryam B. Haddad, PhD[SUP]1[/SUP]; Sandy P. Althomsons, MA, MHS[SUP]1[/SUP]; Lauren Cowan, PhD[SUP]1[/SUP]; J. Steve Kammerer, MBA[SUP]1[/SUP]; Chee Kin Lam, MS, MPH[SUP]1[/SUP]; Clinton J. McDaniel, MPH[SUP]1[/SUP]; James Posey, PhD[SUP]1[/SUP]; Sarah Talarico, PhD[SUP]1[/SUP]; William L. Walker, DVM, PhD[SUP]1[/SUP]; Noah G. Schwartz, MD[SUP]1,[/SUP]*; Jonathan M. Wortham, MD[SUP]1,[/SUP]* (View author affiliations)
Summary
What is already known about this topic?
During 2014–2016, a total of 24 large tuberculosis (TB) outbreaks (10 or more related TB cases within a 3-year period) were identified within the United States, primarily affecting U.S.-born persons.
What is added by this report?
During 2017–2023, a total of 50 large TB outbreaks were identified in 23 states, primarily involving U.S.-born persons. Persons with TB in large outbreaks reported substance use, homelessness, and incarceration more often than did other persons with TB. Two thirds of large outbreaks occurred within family and social networks.
What are the implications for public health practice?
Nationwide capacity for outbreak detection, prevention, and response is critical for reducing outbreak-associated morbidity. Building trust within affected communities and overcoming barriers to diagnosis and treatment associated with homelessness and substance use are critical for outbreak prevention.
Related Materials
Abstract
During 2017–2023, based on an analysis of national genomic and tuberculosis (TB) case surveillance data, 50 large TB outbreaks (10 or more related TB cases in a 3-year period) involving 1,092 cases were identified in 23 states. Compared with 61,993 other persons who received a diagnosis of TB during this period, persons included in large outbreaks were more frequently U.S.-born (79% versus 26%), and a higher percentage reported substance use (27% versus 12%), homelessness (9% versus 5%), and incarceration (11% versus 3%). Approximately one fourth of these large outbreak-related cases were identified through contact tracing; these cases less commonly had clinical markers of highly infectious disease (23%) than did large outbreak-related cases identified through other methods (including evaluation associated with symptoms, targeted testing, or incidental findings) (61%), suggesting that contact tracing might have facilitated earlier diagnosis. Among the 50 large outbreaks, 34 (68%) were primarily associated with family or social networks, and 13 (26%) were primarily associated with congregate settings. Maintaining state and local public health capacity for outbreak detection, prevention, and response is essential, even in low-incidence jurisdictions. Effective outbreak responses must overcome barriers to diagnosis and treatment associated with homelessness and substance use and include efforts to build trust with affected communities. Procedures to promptly identify and isolate persons with infectious TB remain critical in congregate settings...