Introduction

Tuberculosis (TB) is a global disease, found in every country in the world. It is one of the leading infectious causes of death worldwide. The World Health Organization estimates that 1.8 billion people close to one quarter of the world's population are infected with Mycobacterium tuberculosis (M.tb), the bacteria that causes TB. Last year, 10.6 million fell ill from TB and 1.6 million died. TB is an airborne disease that can be spread by coughing or sneezing and is the leading cause of infectious disease worldwide. It is responsible for economic devastation with the cycle of poverty and illness that entraps families, communities and even entire countries. Among the most vulnerable are women, children, and those with HIV/AIDS. There is growing resistance to available drugs, which means the disease is becoming more deadly and difficult to treat. There were more than half a million cases of drug resistant TB last year.⁽¹⁾ 

The current WHO guidelines for the treatment of drug-susceptible pulmonary TB have recommended a 6-month regimen comprising four first-line anti-TB drugs in the intensive phase (for 2 months) and two drugs in the continuation phase (for 4 months) i.e.  2 months of Isoniazid/ Rifampicin/Pyrazinamide/Ethambutoland 4 months of Isoniazid/Rifampicin (2HRZE/4HR).⁽²⁾

India and TB: With 28% cases, India was among the eight countries accounting for more than two-third (68.3%) of the total TB patients’ count. The other countries were Indonesia (9.2% cases), China (7.4%), the Philippines (7%), Pakistan (5.8%), Nigeria (4.4%), Bangladesh (3.6%) and the Democratic Republic of the Congo (2.9%). India accounted for 36% of the global TB related deaths among HIV negative people. India was among the three countries (along with Indonesia and the Philippines) that accounted for most of the reduction in 2020 (67% of the global) and made partial recoveries in 2021.⁽¹⁾

1. Tuberculosis Report 2022: WHO.
2. World Health Organization WHO Consolidated Guidelines on Tuberculosis: Module 4: Treatment: Drug-Susceptible Tuberculosis Treatment.; Available online: https://www.who.int/publications/i/item/9789240048126.
3. Mathema B, Kurepina NE, Bifani PJ, et al. Molecular epidemiology of tuberculosis: Current insights. Clinical Microbiology Reviews. 2006;19(4):658-685. DOI: 10.1128/CMR.00061-05.
4. Panjabi R, Comstock GW, Recurrent GJE. Tuberculosis and its risk factors: Adequately treated patients are still at high risk. The International Journal of Tuberculosis and Lung Disease. 2007;11(8):828-837
5. Gomes MG, Aguas R, Lopes JS, et al. How host heterogeneity governs tuberculosis reinfection? ProcBiol Sci. 2012;279:2473–8.
6. Lambert ML, Hasker E, Van Deun A, Roberfroid D, Boelaert M, Van der Stuyft P. Recurrence in tuberculosis: relapse or reinfection? Lancet Infect Dis. 2003;3:282–7.
7. Benator D, Bhattacharya M, Bozeman L, et al. Rifapentine and isoniazid once a week versus rifampicin and isoniazid twice a week for treatment of drug-susceptible pulmonary tuberculosis in HIV-negative patients: a randomised clinical trial. Lancet. 2002;360:528–34.
8. Shen G, Xue Z, Shen X, et al. Recurrent tuberculosis and exogenous reinfection, Shanghai, China. Emerg Infect Dis. 2006;12:1776–8.
9. van Rie A, Warren R, Richardson M, et al. Exogenous reinfection as a cause of recurrent tuberculosis after curative treatment. N Engl J Med. 1999;341:1174–9
10. Glynn JR, Murray J, Bester A, et al. High rates of recurrence in HIV-infected and HIV-uninfected patients with tuberculosis. The Journal of Infectious Diseases. 2010;201(5):704-711.
11. Charalambous S, Grant AD, Moloi V, et al. Contribution of reinfection to recurrent tuberculosis in South African gold miners. The International Journal of Tuberculosis and Lung Disease. 2008;12:942-948.
12. Narayanan S, Swaminathan S, Supply P, et al. Impact of HIV infection on the recurrence of tuberculosis in South India. The Journal of Infectious Diseases. 2010;201:691-703.
13. World Health Organization. WHO Report 2009. Global tuberculosis control: epidemiology, strategy, financing. 2009 Jul 11; WHO/HTM/TB/2009.411. http://www.who.int/entity/tb/publications/global_report/2009/pdf/full_report.pdf.
14. Golub JE, Durovni B, King BS, et al. Recurrent tuberculosis in HIV-infected patients in Rio de Janeiro, Brazil. AIDS. 2008;22:2527–2533.
15. Korenromp EL, Scano F, Williams BG, Dye C, Nunn P. Effects of human immunodeficiency virus infection on recurrence of tuberculosis after rifampin-based treatment: an analytical review. Clin Infect Dis. 2003;37:101–12.
16. Rosenthal IM, Zhang M, Williams KN, et al. Daily dosing of rifapentine cures tuberculosis in three months or less in the murine model. PLoS Med. 2007 Dec 18;4(12):e344.

Dr Rajendra Tatu Nanavare

Chest Physician (SMC) and Unit head IV Group of T.B. Hospitals, Sewri, Mumbai-15