Tuberculosis prevention in healthcare workers in China 10 years after the severe acute respiratory syndrome pandemic

Deng, Yunfeng; Li, Yan; Wang, Fengtian; Gao, Dachuan; Li, Liang; Teeter, Larry D.; Graviss, Edward A.; Ma, Xin

The goal of the present study was to investigate and describe latent TB infection (LTBI) among HCWs in China, and the effectiveness of infection control strategies in TB hospitals using the T-SPOT.TB assay and TST. This study was conducted in two major primary referral hospitals for TB patients and other respiratory infectious diseases in Shandong Province, China, in 2013: the Shandong Provincial Chest Hospital (SPCH), Jinan; and Linyi Municipal Chest Hospital (LMCH), Linyi. Approximately 3000 patients with active TB disease are treated in each hospital annually. Since 2004, both hospitals have been equipped with BSL3 laboratories that are used for mycobacterial specimen testing (acid-fast bacillus (AFB) smear test, culture and species identification) and respiratory isolation wards with negative pressure rooms for smear-positive TB patients. As recommended by China's National Tuberculosis Control Programme, the TST was carried out by the Mantoux method using a 5 tuberculin unit dose of BCG purified protein derivative (Chengdu Institute of Biological Products, Chengdu, China). An induration of ⩾10 mm was defined as a positive TST. A blood sample for the T-SPOT.TB assay was drawn from each HCW before the TST was performed. T-SPOT.TB assays were carried out and interpreted according to the manufacturer's instructions. Spot counts were analysed using an ELISPOT reader (CTL-ImmunoSpot S5 Core Analyzer; Cellular Technology Ltd, Shaker Heights, OH, USA). Covariates (age, sex, working year and job category) associated with positive T-SPOT.TB results were analysed by univariate and multivariate analyses. Univariate p-values were determined for each covariate by logistic regression. Covariates with univariate p-values <0.20 were included in multivariate logistic regression models. Statistical analysis was performed using Stata/SE version 13.1 (StataCorp LP, College Station, TX, USA). The study protocol was approved by the institutional review boards of SPCH and LMCH.