Genotyping indicates marked heterogeneity of tuberculosis transmission in the United States, 2009–2018. (14th September 2021)

• Record Type: Journal Article
• Authors: Rodriguez, Carly A.; Li, Tenglong; Self, Julie L.; Jenkins, Helen E.; Horsburgh, Charles R.; White, Laura F.
• Is Part Of: Epidemiology and infection. Volume 149(2021)
• Publication Date: 2021-09-14
• Subjects: epidemiology -- tuberculosis (TB); Communicable diseases -- Periodicals; Epidemiology -- Periodicals; 614.4
• DOI: 10.1017/S0950268821002041
• Languages: English
• ISSNs: 0950-2688

Abstract

Abstract: Heterogeneity in the number of secondary tuberculosis (TB) cases per source case, the effective reproductive number, R, is important in modelling prevention strategies' impact on incidence. We estimated mean R ( R m ) and calculate the dispersion parameter of this distribution, k, using surveillance and genotyping data for U.S. cases during 2009–2018. We modelled transmission assuming cases in a cluster have matching genotypes and share characteristics related to geography, temporal proximity (i.e. serial interval) and time since U.S. arrival among non-U.S.-born persons. Complete data were available for 55 330/85 958 cases. Varying the serial interval and geographic proximity used to derive clusters, we consistently estimated R m <1.0 and k < 0.08; the low value of k indicates a small number of source cases produce a disproportionate number of secondary cases. U.S. TB reproductive number has a highly skewed distribution, indicating a minority of source cases disproportionately contribute to transmission.