Abstract
Background & Objective: Identification and treatment of latent-tuberculosis-infection (LTBI) has remained at backstage for long. This study looks at the effect of graded-increase in clinical exposure on incidence of LTBI in health-care students and their non-exposed peers.
Methods: It was a cross-sectional observational study including 817 students (medical and non-medical). A one-step tuberculin-skin-test (TST) was performed using Monteux-technique. A positive TST, induration of ≥10 mm, was considered suggestive of LTBI. Prevalence of LTBI was recorded among students of successive years and comparisons were made, in the two groups, with demographic variables.
Results: Mean age of the study population was 20.83±1.86 years. 73.19% students were from an urban-background and 67.68% were from high-income-group. In medical and nursing group 29.08% and 30.55% students had TST positivity as compared to 14.23% in engineering students. Over four-years, the percentage of medical and nursing students having positive-TST increased from 13% to ≥40% (p<0.05), but no such change was present among engineering students. Relative-risk of acquiring LTBI in medical profession was ≥2.1 as compared to non-medical profession. There was a strong correlation of TST-positivity with increasing clinical exposure in the form of medical/surgical postings even after excluding TST-positivity due to community exposure (p<0.01). There was no association of TST positivity with gender, residence, family income, parents education and occupation and BCG vaccination (p>0.05).
Conclusion: In our study, a higher prevalence of latent tuberculosis infection was demonstrated among medical and nursing students as compared to engineering students. This data favours further studies on the role of heightened infection control practices and potential role of treating LTBI among healthcare-workers.
Keywords: Healthcare workers, Latent-tuberculosis-infection, Medical-students, Monteux-test, tuberculin skin test
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Corresponding Author
Dr Lokesh Kumar Lalwani
Assistant Professor, Department of Tuberculosis & Respiratory Diseases, Post Graduate Institute of Medical Sciences, Rohtak (Haryana), India-124001
DOI: https://dx.doi.org/10.18535/jmscr/v9i5.15
