Main Article Content
Airborne and Tuberculosis (TB) control measures have been implemented in Songklanagarind hospital. The infection control unit of the hospital has provided a voluntary two-step tuberculin skin test (TST) for pre-clinical medical students and serial TST for clinical medical students. This study aimed to determine the incidence of negative outcome and booster phenomenon from two-step TST as well as the TST conversion rate from serial TST among medical students in the hospital.
MATERIALS AND METHODS:
Percentages of negative cases and boosting phenomenon were calculated from the two-step TST records. Conversion rates of each year were calculated from serial TST data. Then the TST conversion rates were predicted based on the Jointpoint model.
Two-step TSTs performed from 2001 to 2016 showed 40 to 100% of negative cases and zero to 14% of boosting phenomenon among 2,271 medical students. Serial TSTs from 2002 to 2016 among 665 medical students showed 60 conversion cases. Conversion rates varied from zero to 13.6%. The decline of conversion rates after the year 2006 is demonstrated in 1-Joinpoint model with statistical significance (p = 0.0129). The model corresponded with the timeline data of airborne infection control measures which were mostly implemented after 2006.
A decline in TST conversion rate was shown after 2006. This coincided with airborne infection control measures at the institute.
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2. World Health Organization. Global tuberculosis report 2017. Geneva: WHO; 2015.
3. Committee on regulating occupational exposure to tuberculosis, division of health promotion and disease prevention. Tuberculosis in the workplace. Washington, D.C. United States of America: National Academy Press; 2001.
4. Bonnoci FG, Nair N, Kamble SP. Tuberculosis control in the workplace. In: Schaaf HS, Zumala A, editors. Tuberculosis. A comprehensive clinical reference: Saunders Elsavier; 2009:903-7.
5. World Health Organization. Guidelines on the management of latent tuberculosis infection. Spain: WHO; 2015.
6. Joshi R, Reingold AL, Menzies D, et al. Tuberculosis among health-care workers in low- and middle-income countries: a systematic review. PLoS Med 2006;3:e494.
7. Nasreen S, Shokoohi M, Malvankar-Mehta MS. Prevalence of latent tuberculosis among health care workers in high burden countries: a systematic review and meta-analysis. PLoS One 2016;11.
8. Hohmuth BA. Latent tuberculosis infection: risks to health care students at a hospital in Lima, Peru. Int J Tuberc Lung Dis 2006;10:1146-51.
9. Jirasmitha S, Natekaew P, Siriwat T, et al. Tuberculous infection among clinical year medical students in Budhachinaraj Hospital at Phitsanulok. Thai J Tuberc Chest Dis Cnt Care 2007;28:129-34.
10. Na Narong M, Thongpiyapoom S, Dilpapajakul K, et al. Tuberculin skin test conversion in health care personnel in a university hospital. J Infect Dis Antimicrob Agents 1999;16: 13-5.
11. Schepisi MS, Sotgiu G, Contini S, et al. Tuberculosis transmission from healthcare workers to patients and co-workers: a systematic literature review and meta-analysis. PLoS One 2015;10:e0121639.
12. Menzis D, Schwartzman K, Pai M. Immune-bases tests for tuberculosis. In: Schaaf HS, Zumala A, editors. Tuberculosis. A comprehensive clinical reference: Saunders Elsevier; 2009:179-85.
13. Udompanich V. TB diagnosis. Thai J Tuberc Chest Dis Cnt Care 2009;30:3-22.
14. Casas I, Esteve M, Guerola R, et al. Incidence of tuberculosis infection among healthcare workers: risk factors and 20-year evolution. Respir Med 2013;107:601-7.
15. da Costa PA, Trajman A, Mello FC, et al. Administrative measures for preventing Mycobacterium tuberculosis infection among healthcare workers in a teaching hospital in Rio de Janeiro, Brazil. J Hosp Infect 2009;72:57-64.
16. Incidence of tuberculosis [Internet]. The World Bank Group, 2018 (Accessed Janaury 19, 2018, at https://databank. worldbank.org/data/reports.aspx?source=2&series=SH.TBS. INCD&country=)