key: cord-1019741-by45h3rm
authors: Filardo, Thomas D.; Feng, Pei-Jean; Pratt, Robert H.; Price, Sandy F.; Self, Julie L.
title: Tuberculosis — United States, 2021
date: 2022-03-25
journal: MMWR Morb Mortal Wkly Rep
DOI: 10.15585/mmwr.mm7112a1
sha: 20f0c3edcb3ab9c48925c71967630e17a39fddde
doc_id: 1019741
cord_uid: by45h3rm

During 1993-2019, the incidence of tuberculosis (TB) in the United States decreased steadily; however, during the later years of that period the annual rate of decline slowed (1) until 2020 when a substantial decline (19.9%) was observed. This sharp decrease in TB incidence might have been related to multiple factors coinciding with the COVID-19 pandemic, including delayed or missed TB diagnoses or a true reduction in TB incidence related to pandemic mitigation efforts and changes in immigration and travel (2). During 2021, a total of 7,860 TB cases were provisionally reported to CDC's National Tuberculosis Surveillance System (NTSS) by the 50 U.S. states and the District of Columbia (DC). National incidence of reported TB (cases per 100,000 persons) rose 9.4% during 2021 (2.37) compared with that in 2020 (2.16) but remained 12.6% lower than the rate during 2019 (2.71).* During 2021, TB incidence increased among both U.S.-born and non-U.S.-born persons. The increased TB incidence observed during 2021 compared with 2020 might be partially explained by delayed diagnosis of cases in persons with symptom onset during 2020; however, the continued, substantial reduction from prepandemic levels raises concern for ongoing underdiagnosis. TB control and prevention services, including early diagnosis and complete treatment of TB and latent TB infection, should be maintained and TB awareness promoted to achieve elimination in the United States.

During 1993-2019, the incidence of tuberculosis (TB) in the United States decreased steadily; however, during the later years of that period the annual rate of decline slowed (1) until 2020 when a substantial decline (19.9%) was observed. This sharp decrease in TB incidence might have been related to multiple factors coinciding with the COVID-19 pandemic, including delayed or missed TB diagnoses or a true reduction in TB incidence related to pandemic mitigation efforts and changes in immigration and travel (2) . During 2021, a total of 7,860 TB cases were provisionally reported to CDC's National Tuberculosis Surveillance System (NTSS) by the 50 U.S. states and the District of Columbia (DC). National incidence of reported TB (cases per 100,000 persons) rose 9.4% during 2021 (2.37) compared with that in 2020 (2.16) but remained 12.6% lower than the rate during 2019 (2.71).* During 2021, TB incidence increased among both U.S.-born and non-U.S.-born persons. The increased TB incidence observed during 2021 compared with 2020 might be partially explained by delayed diagnosis of cases in persons with symptom onset during 2020; however, the continued, substantial reduction from prepandemic levels raises concern for ongoing underdiagnosis. TB control and prevention services, including early diagnosis and complete treatment of TB and latent TB infection, should be maintained and TB awareness promoted to achieve elimination in the United States.

Health departments in the 50 U.S. states and DC report TB cases to CDC based on the Council of State and Territorial Epidemiologists' surveillance case definition, which includes both laboratory and clinically verified cases. † For each case, health departments electronically submit a report of a verified TB case to CDC. Midyear U.S. Census Bureau population estimates § were used to calculate national-and state-level TB incidence per 100,000 persons along with incidence stratified by age groups. Persons with TB were grouped by self-reported race and ethnicity according to federal guidelines. ¶ Persons who self-identified as Hispanic were categorized as Hispanic irrespective of self-reported race, persons not identifying as Hispanic were categorized by self-reported race, and non-Hispanic persons who reported more than one race were § 2021 vintage population estimates were used for 2021 and 2020. 2020 vintage population estimates were used for 2011-2019. https://www.census.gov/ programs-surveys/popest/data/tables.html ¶ https://www.census.gov/topics/population/race/about.html categorized as "multiple races." Midyear population estimates from the Current Population Survey** were used to calculate incidence by birth origin † † and race/ethnicity. Percent changes in incidence were calculated using unrounded figures.

A total of 7,860 TB cases were reported during 2021, 687 more than during 2020 (7,173) and 1,040 fewer than during 2019 (8,900) ( Table 1) . From 2020 to 2021, TB incidence (cases per 100,000 population) rose 9.4%, from 2.16 to 2.37, but remained 12.6% lower than during 2019 (2.71). California reported the highest number of cases (1, 750) , and Alaska reported the highest incidence (7.92). Eighteen states and DC reported the same number or fewer TB cases during 2021 than during 2020; the remaining 32 states reported more cases during 2021 than 2020.

During 2021, 71% of TB cases occurred among non-U. 1993, with a slowing pace of decline in recent years (1), larger changes in reported TB have occurred during the COVID-19 pandemic. Similar changes in TB incidence have been reported globally (3, 4) . In the United States, the causes for the changes in TB incidence are likely multifactorial. Probable explanations include a true reduction in TB disease resulting from reduced TB transmission because of pandemic mitigation efforts and fewer new arrivals from countries with higher TB incidence than the United States. In addition, delayed or missed TB diagnoses because of disruptions in health care access or assumptions that patients with respiratory symptoms had COVID-19 might contribute to the observed changes (5) . The reduction in the number of persons with TB disease reported <1 year after arrival in the United States coincides with changes in immigration and travel associated with the pandemic. Immigration to the United States declined by 31% during 2020, † † † and similar patterns are suggested during 2021. § § § However, immigration and travel reductions during 2020-2021 cannot fully account for the reduction in TB, because most TB cases among non-U.S.-born persons occur among those who have lived in the United States for many years and are likely the result of reactivation of latent TB infection (LTBI) (1). Despite overall case count declines, the number of TB cases among non-U.S.-born persons living in the United States for 20 years or longer before diagnosis increased during 2021 compared with average case counts during 2015-2019, highlighting the importance of evaluation and treatment of LTBI to prevent progression to TB disease. CDC is working to raise awareness of TB and LTBI among communities at risk and their health care providers through the new "Think. Test. Treat TB" campaign. ¶ ¶ ¶ The increased TB incidence observed during 2021 compared with 2020 might be partially explained by delayed detection of cases with symptom onset during 2020 that were not diagnosed until 2021 because of delayed health care-seeking behavior, interruptions in health care access, or disrupted TB § § § https://www.census.gov/library/stories/2021/12/net-internationalmigration-at-lowest-levels-in-decades.html ¶ ¶ ¶ https://www.cdc.gov/thinktesttreattb/ services related to the COVID-19 pandemic (6, 7) . The small increase in the prevalence of smear positivity at diagnosis, predominantly among non-U.S.-born persons, suggests more advanced pulmonary disease, which might result from delayed diagnosis. Avoiding missed or delayed diagnosis of TB is crucial to preventing transmission. TB should be considered in the differential diagnosis of patients with prolonged cough (>2 weeks) or TB symptoms such as unintentional weight loss or hemoptysis, particularly among persons with epidemiologic risk factors for TB (e.g., birth or former residence in a country with higher TB incidence than that in the United States, history of living in a congregate setting such as a homeless shelter or a correctional facility, or immune suppression).**** The findings in this report are subject to at least two limitations. First, this analysis is limited to provisional 2021 TB surveillance data and case counts might change. Second, calculated rates are based on population estimates that are subject to change. **** Clinical consultation for potential TB cases is also available through state or local TB programs or the CDC-sponsored TB Centers of Excellence. https://www.cdc.gov/tb/education/professionaltools.htm

What is already known about this topic?

The number of reported U.S. tuberculosis (TB) cases decreased sharply in 2020, possibly related to multiple factors associated with the COVID-19 pandemic.

What is added by this report?

Reported TB incidence (cases per 100,000 persons) increased 9.4%, from 2.2 during 2020 to 2.4 during 2021 but was lower than incidence during 2019 (2.7). Increases occurred among both U.S.-born and non-U.S.-born persons.

What are the implications for public health practice?

Factors contributing to changes in reported TB during 2020-2021 likely include an actual reduction in TB incidence as well as delayed or missed TB diagnoses. Timely evaluation and treatment of TB and latent tuberculosis infection remain critical to achieving U.S. TB elimination.

Ongoing analyses of NTSS data and external data sources, including anti-TB drug dispensing and hospitalization data, will provide more information about the effects of the COVID-19 pandemic on U.S. TB epidemiology, including the extent to which delayed diagnosis has been a factor. Focusing on essential TB activities, including early diagnosis and complete treatment of TB and LTBI, remains critical to achieving TB elimination in the United States.

GA: US Department of Health and Human Services, CDC

Tuberculosis-United States

World Health Organization

COVID-19's devastating effect on tuberculosis care-a path to recovery

Delayed tuberculosis diagnoses during the coronavirus disease 2019 (COVID-19) pandemic in 2020

Tuberculosis-associated hospitalizations and deaths after COVID-19 shelter-in-place

Notes from the field: effects of the COVID-19 response on tuberculosis prevention and control efforts-United States

State, local, and territorial health department personnel; Cynthia Adams, Stacey Parker, Jeanette Roberts, Katrina Williams, Peraton, Herndon, Virginia; Division of Tuberculosis Elimination surveillance team, National Center for HIV, Viral Hepatitis, STD, and TB Prevention, CDC; Molly Deutsch-Feldman, Adam Langer, Jonathan Wortham, National Center for HIV, Viral Hepatitis, STD, and TB Prevention, CDC.All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.