Prevalence of latent tuberculosis infection in household contacts of pulmonary tuberculosis, time to treat

Submitted: February 23, 2023
Accepted: May 12, 2023
Published: May 22, 2023
Abstract Views: 732
PDF: 297
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Treatment of latent pulmonary tuberculosis (TB) in household contacts has been included in the National Tuberculosis Elimination Program to achieve the target of TB elimination by the Government of India by 2025. However, there are no clear estimates of the prevalence of latent TB among the contacts that could suggest the impact of this intervention. The study was conducted to determine the prevalence of and factors predicting latent TB among household contacts with pulmonary TB. All microbiologically confirmed pulmonary TB patients registered between January 2020 and July 2021 and their household contacts were enrolled. All contacts underwent Mantoux testing to determine the prevalence of latent TB. All symptomatic patients also underwent chest radiographs and sputum examinations to diagnose active pulmonary TB. Thereafter, different demographic and clinical factors were evaluated to find predictors of latent TB using a logistic regression model. A total of 118 pulmonary TB cases and their 330 household contacts were enrolled. The prevalence of latent TB and active TB among the contacts was found to be 26.36% and 3.03%, respectively. The female gender of index TB cases was independently associated with a high proportion of latent TB cases in the family (adjusted odds ratio 2.32; 95% confidence interval 1.07-5.05; p=0.03). Neither the higher sputum smear positivity nor the severity of the chest radiograph of index TB cases had any association with the number of contacts being diagnosed as latent TB or active TB. The results showed a significant prevalence of latent TB among household contacts with pulmonary TB. The severity of the disease in the index patient had no association with the prevalence of latent TB.



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World Health Organization. Global tuberculosis report 2021. Available from: Accessed on: 4/01/2022.
Smith I. Mycobacterium tuberculosis pathogenesis and molecular determinants of virulence. Clin Microbiol Rev 2003;16:463-96.
Doucette K, Cooper R. Tuberculosis. In: Grippi MA, Elias JA, Fishman JA, Kotloff RM, Pack AI, Senior RM, eds. Fishman’s pulmonary diseases and disorders, 5th ed. New York, NY: McGraw-Hill; 2015. pp 2014-15.
World Health Organization. Systematic screening for active tuberculosis: principles and recommendations. World Health Organization; 2013. Available from: Accessed on: 5/11/2019.
Houben RM, Dodd PJ. The global burden of latent tuberculosis infection: a re-estimation using mathematical modelling. PLoS Med 2016;13:e1002152.
Krishnamoorthy Y, Ezhumalai K, Murali S, et al. Prevalence and risk factors associated with latent tuberculosis infection among household contacts of smear positive pulmonary tuberculosis patients in South India. Trop Med Int Health 2021;26:1645-51.
Praveen V. Prevalence of LTBI among household contacts of sputum positive TB patients receiving DOTS chemotherapy. Indian J Tuberc 2020;67:459-65.
Nair D, Rajshekhar N, Klinton JS, et al. Household contact screening and yield of tuberculosis cases - a clinic based study in Chennai, South India. PLoS One 2016;11:e0162090.
Ministry of Health and Family Welfare. Guidelines for programmatic management of drug resistant tuberculosis in India, 2021. Available from: Accessed on: 14/01/2022.
Pai M, Joshi R, Kalantri S. Diagnosis of latent tuberculosis infection: recent advances and future directions. In: Sharma SK, Mohan A, eds. Tuberculosis, 2nd ed. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd; 2009. pp 186-99.
Sprinson JE, Flood J, Fan CS, et al. Evaluation of tuberculosis contact investigations in California. Int J Tuberc Lung Dis 2003;7:S363-8.
Mandal P, Craxton R, Chalmers JD, et al. Contact tracing in pulmonary and non-pulmonary tuberculosis. QJM 2012;105:741-7.
Hector J, Anderson ST, Banda G, et al. TST positivity in household contacts of tuberculosis patients: a case-contact study in Malawi. BMC Infect Dis 2017;17:259.
Xu J, Hu Y, Jiang W, et al. Prevalence and risk factors of latent tuberculosis infection in close contacts of tuberculosis patients among non-resident populations in Shanghai, China. Zhonghua Jie He He Hu Xi Za Zhi 2016;39:25-9. [Article in Chinese].
Khaparde K, Jethani P, Dewan PK, et al. Evaluation of TB case finding through systematic contact investigation, Chhattisgarh, India. Tuberc Res Treat 2015;2015:670167.
Beyanga M, Kidenya BR, Gerwing-Adima L, et al. Investigation of household contacts of pulmonary tuberculosis patients increases case detection in Mwanza City, Tanzania. BMC Infect Dis 2018;18:110.
Kilicaslan Z, Kiyan E, Kucuk C, et al. Risk of active tuberculosis in adult household contacts of smear-positive pulmonary tuberculosis cases. Int J Tuberc Lung Dis 2009;13:93-8.
Htet KKK, Liabsuetrakul T, Thein S, et al. Improving detection of tuberculosis among household contacts of index tuberculosis patients by an integrated approach in Myanmar: a cross-sectional study. BMC Infect Dis 2018;18:660.
Velayutham B, Jayabal L, Watson B, et al. Tuberculosis screening in household contacts of pulmonary tuberculosis patients in an urban setting. PLoS One 2020;15:e0240594.
Little KM, Msandiwa R, Martinson N, et al. Yield of household contact tracing for tuberculosis in rural South Africa. BMC Infect Dis 2018;18:299.
Xu C, Hu B. Prevalence of active pulmonary tuberculosis among household contacts of recently diagnosed pulmonary tuberculosis patients with positive sputum-smear. Zhonghua Jie He He Hu Xi Za Zhi 2008;29:693-5. [Article in Chinese].

Ethics Approval

The study protocol was reviewed and approved by the Institutional Ethics Committee of Government Medical College and Hospital (No.GMCH/IEC/2019/142/).

How to Cite

Sangma, Vinnie Sarah Ch, Surabhi Jaggi, Varinder Saini, Deepak Aggarwal, Pankaj Kumar, and Jagdish Chander. 2023. “Prevalence of Latent Tuberculosis Infection in Household Contacts of Pulmonary Tuberculosis, Time to Treat”. Monaldi Archives for Chest Disease 94 (1).