Association between Birth Region and Time to Tuberculosis Diagnosis among Non-US-Born Persons in the United States.

Amish Talwar,Adam J Langer,Rongxia Li

doi:10.3201/eid2706.203663

Abstract

Approximately 90% of tuberculosis (TB) cases among non–US-born persons in the United States are attributable to progression of latent TB infection to TB disease. Using survival analysis, we investigated whether birthplace is associated with time to disease progression among non–US-born persons in whom TB disease developed. We derived a Cox regression model comparing differences in time to TB diagnosis after US entry among 19 birth regions, adjusting for sex, birth year, and age at entry. After adjusting for age at entry and birth year, the median time to TB diagnosis was lowest among persons from Middle Africa, 128 months (95% CI 116–146 months) for male persons and 121 months (95% CI 108–136 months) for female persons. We found time to TB diagnosis among non–US-born persons varied by birth region, which represents a prognostic indicator for progression of latent TB infection to TB disease.

Highlights

Most incident tuberculosis (TB) cases in the United States occur among non–US-born persons [1]
Most non–US-born persons who developed TB disease not attributed to recent transmission after arrival to the United States emigrated from Asia (Table 1); the subregion or intermediary region with the highest proportion of non–US-born persons who received a TB diagnosis in the United States not attributed to recent transmission was South-eastern Asia
The unadjusted median number of months that a non–US-born person who developed TB disease spent in the United States before receiving a TB diagnosis not attributed to recent transmission was 143 months (IQR 51–292 months)

Summary

Introduction

Most incident tuberculosis (TB) cases in the United States occur among non–US-born persons [1]. Persons recently infected with TB and persons with weakened immune systems are at higher risk for progression to TB disease [6], the factors affecting the time to develop TB disease remain unclear, for non–US-born persons. Information on time to develop TB disease can help public health officials target interventions for LTBI testing and treatment among at-risk populations before LTBI progresses to TB disease. Non– US-born persons are a heterogenous population who differ in health status based on country of origin [8], and the effect of birth country on progression from LTBI to TB disease remains unclear. To clarify disease progression among varying population groups, we evaluated the time to develop TB disease according to birthplace among non–US-born persons with reported cases of TB disease in the United States during 2011–2018

Methods

Results

Conclusion