high annual risk of tuberculosis infection among nursing students in south india a cohort study高年度感染肺结核的风险在印度南部的护理学生队列研究.pdfVIP

High Annual Risk of Tuberculosis Infection among Nursing Students in South India: A Cohort Study 1 1 2 1 1 Devasahayam J. Christopher , Prince James , Peter Daley , Lois Armstrong , Barney T. J. Isaac , 1 1 3 3 Balamugesh Thangakunam , Beulah Premkumar , Alice Zwerling , Madhukar Pai * 1 Christian Medical College, Vellore, India, 2 Memorial University, St. John’s, New Foundland, Canada, 3 McGill University, Montreal, Quebec, Canada Abstract Background: Nurses in developing countries are frequently exposed to infectious tuberculosis (TB) patients, and have a high prevalence of TB infection. To estimate the incidence of new TB infection, we recruited a cohort of young nursing trainees at the Christian Medical College in Southern India. Annual tuberculin skin testing (TST) was conducted to assess the annual risk of TB infection (ARTI) in this cohort. Methodology/Principal Findings: 436 nursing students completed baseline two-step TST testing in 2007 and 217 were TST- negative and therefore eligible for repeat testing in 2008. 181 subjects completed a detailed questionnaire on exposure to tuberculosis from workplace and social contacts. A physician verified the questionnaire and clinical log book and screened the subjects for symptoms of active TB. The majority of nursing students (96.7%) were females, almost 84% were under 22 years of age, and 80% had BCG scars. Among those students who underwent repeat testing in 2008, 14 had TST conversions using the ATS/CDC/IDSA conversion definition of 10 mm or greater increase over baseline. The ARTI was therefore estimated as 7.8%