Infectious Disease
We Built This City: Changes to metropolitan TB patterns during the COVID-19 pandemic Victoria Fisher* Victoria Fisher Nadia Abuelezam
Background: After a drop in reported tuberculosis (TB) in 2020, cases in the U.S. are on the rise. The COVID-19 pandemic changed how and where we live, which has implications for infectious diseases, like TB, commonly associated with dense living conditions. The majority of reported TB cases come from large metropolitan areas. We aim to explore if trends in TB incidence have changed in the “post-COVID” era by metro typology.
Methods: County TB case data, the outcome, was taken from the CDC; county-level demographics are from the American Community 5-Year Survey for 2017-2022. The exposure, metro typology score (lower = more “metro”), comes from the USDA. Covariates included pre- (2017-2019) and post-pandemic (2020-2022) eras, county total population, percent male, percent receiving public assistance, average household density, and percent who live below the poverty level. We assessed the relationship between typology category and TB incidence via mixed effect Poisson regression models.
Findings: Across 330 counties (2017-2022), the mean TB cases count was 29.5 (95% CI: 26.7, 32.4). Mean county typology score was 1.64 (95% CI: 1.6, 1.7). There is a weak, negative correlation between total cases and county typology score (R = -0.22, 95% CI: -0.27, -0.17). In the unadjusted model, the least metro counties were significantly associated with a post-COVID TB incidence rate ratio (IRR) of 8.6 (95% CI: 5.3, 14.3); the most metro counties were significantly associated with a 0.83 (95% CI: 0.82, 0.86) post-COVID IRR. In the fully adjusted model, the least metro counties were significantly associated with a post-COVID TB IRR of 5.0 (95% CI: 3.0, 7.0); the most metro counties were significantly associated with a post-COVID TB IRR of 0.82 (95%CI: 0.8, 0.84).
Discussion: Our results suggest that in the post-COVID era large metro counties have continued to see a decrease in TB incidence while smaller metro and micro counties are experiencing steeper incidence rates.