Estimated Rate of Reactivation of Latent Tuberculosis Infection in the United States, Overall and by Population Subgroup

Abstract

We estimated the rate of reactivation tuberculosis (TB) in the United States, overall and by population subgroup, using data on TB cases and Mycobacterium tuberculosis isolate genotyping reported to the Centers for Disease Control and Prevention during 2006–2008. The rate of reactivation TB was defined as the number of non-genotypically clustered TB cases divided by the number of person-years at risk for reactivation due to prevalent latent TB infection (LTBI). LTBI was ascertained from tuberculin skin tests given during the 1999–2000 National Health and Nutrition Examination Survey. Clustering of TB cases was determined using TB genotyping data collected by the Centers for Disease Control and Prevention and analyzed via spatial scan statistic. Of the 39,920 TB cases reported during 2006–2008, 79.7% were attributed to reactivation. The overall rate of reactivation TB among persons with LTBI was estimated as 0.084 (95% confidence interval (CI): 0.083, 0.085) cases per 100 person-years. Rates among persons with and without human immunodeficiency virus coinfection were 1.82 (95% CI: 1.74, 1.89) and 0.073 (95% CI: 0.070, 0.075) cases per 100 person-years, respectively. The rate of reactivation TB among persons with LTBI was higher among foreign-born persons (0.098 cases/100 person-years; 95% CI: 0.096, 0.10) than among persons born in the United States (0.082 cases/100 person-years; 95% CI: 0.080, 0.083). Differences in rates of TB reactivation across subgroups support current recommendations for targeted testing and treatment of LTBI.

The Secreted Protein Rv1860 of Mycobacterium tuberculosis Stimulates Human Polyfunctional CD8+T Cells

“…Several subsets of Rv1860-specific polyfunctional CD4 ϩ and CD8 ϩ T cells were significantly more numerous in HV than in PAT, in contrast to the reported superior CD4 ϩ T cell responses to ESAT-6, CFP-10, Ag85A, and Ag85B in TB patients (21)(22)(23)42). Our results suggest that Rv1860, by virtue of its capacity to stimulate CD8 ϩ T cells, may serve as a useful candidate for inclusion in a TB vaccine with the potential for preventing the reactivation of latent M. tuberculosis infections which accounts for up to 80% of TB cases in some countries (43). We also identified a peptide spanning amino acids (aa) 21 to 39 of the Rv1860 protein sequence that gave rise to a mutually exclusive proliferation and cytokine signature from stimulated peripheral blood mononuclear cells (PBMC) of HV and PAT, revealing the potential for its use for evaluating new therapeutic agents and for monitoring progression from TB latency to disease.…”

Latent tuberculosis infection: An overview

“…Reactivation is the process by which a subclinical latent infection transitions into active TB disease. Thus, individuals with LTBI represent a major reservoir for new active TB cases (9).…”

“…This framework was designed recognizing that in low incidence countries, TB transmission is infrequent within the general population, and aside from occasional outbreaks, most cases of active TB are due to reactivation of LTBI (9,39).…”

A Short Interfering Rna Molecular Beacon for the Attenuation of Mycobacterial Infection

“…Latent Tuberculosis (LTB) is a persistent problem in both highly industrialized and developing countries (WHO, 2013;Shea et al, 2014). LTB is characterized by pulmonary granulomas which allow Mycobacterium tuberculosis (Mtb) to survive for years without detection (Barry et al, 2009;Rajni and Meena, 2011).…”