The prevalence of latent tuberculosis infection among final year medical students of the university of Nairobi, Kenya

Abstract

Background: Health care workers (HCWs) are at higher than average risk of infection with mycobacterium tuberculosis (TB) and of developing tuberculosis disease. The risk includes infection with multi-drug resistant TB (MDR TB) strains. Little is known about the prevalence of latent tuberculosis infections (LTBI) in HCWs in Kenyatta National Hospital oramong medical students who carry out clerkship in the medical wards. Objective: The aim of the study was to determine the prevalence of latent TB Infection in fifth year medical students ofthe University of Nairobi using the interferon gamma release assay (IGRA)-Quantiferon Tb Gold (QFT-Gold) and to evaluate factors associated with the TB infection. Design:A cross sectional study. Methodology: The study was conducted between September and November 2013. A total of 181 final year medical students were interviewed using a standardized questionnaire and underwentQFT-Gold testing. Results: The median age of the participants was 24 years (Range 22-31 years). Over half (51%)of the students were female. Majority (89.5%) had close contact with a person with TB. Many (72.9%) had been in boarding schools. The students had undergone a clerkship course in the medical wards for a mean duration of 19.2 weeks. The prevalence of TB infection using QFT-Gold was 30% (54/181). The prevalence of latent TB infection among final year medical students at was 24.9%. No variable was found to influence the prevalence of latent TB significantly. Conclusion: A high prevalence of LTBI was found among final year medical students at the national referral hospital.