Indian Journal of Respiratory Care
Volume 12 | Issue 1 | Year 2023

Impact of COVID-19 Coinfection on Management of Tuberculosis Patients registered at DOTS center in a Tertiary Care Hospital

Ruchi A Sachdeva1, Litika Verma2, Lokesh Parashar3, Manas Kamal Sen4, Kamran Chaudhary5, Harshita6, Avinash Kumar7, Amrita Swati8

1-8Department of Respiratory Medicine, ESIC Medical College and Hospital, Faridabad, Haryana, India

Corresponding Author: Ruchi A Sachdeva, Department of Respiratory Medicine, ESIC Medical College and Hospital, Faridabad, Haryana, India, Phone: +91 9999571169, e-mail: drruchiarorasachdevaesic@gmail.com

Received on: 09 March 2022; Accepted on: 06 December 2022; Published on: 14 March 2023


Introduction: This study was conducted to determine the impact of coronavirus disease 2019 (COVID-19) and the ensuing lockdown on tuberculosis (TB) management undergoing treatment under the National Tuberculosis Elimination Program (NTEP) and vice-versa.

Aims: To study (1) the occurrence of COVID-19 and its severity among patients suffering from TB and (2) the impact of a pandemic on TB management under NTEP.

Materials and methods: A retrospective observational study was conducted in patients registered at Directly observed therapy short-course (DOTS) center from 1st April 2020 to 31st July 2021 at ESIC Medical College and Hospital, Faridabad, Haryana, India, using a semi-structured predesigned questionnaire administered telephonically.

Results: Out of 387 TB patients registered at the DOTS center, 191 participated in the study. The occurrence of COVID-19 in patients with TB was 10 (5.2%), of which five (50%) were symptomatic; four (40%) had pulmonary TB, and six (60%) had extrapulmonary TB. Nine (90%) patients had mild and one (10%) moderately severe disease requiring hospitalization. Amongst 191 patients, 29 (15.2%) missed anti-TB treatment (ATT); 15 (51.7%) could not access the DOTS center due to restrictions, and seven (24.1%) due to personal reasons, eight (27.5%) forgot to take medication, and one (0.34%) migrated elsewhere.

Conclusions: The occurrence of COVID-19 in patients with TB was found to be 5.2% in this study. The severity of COVID-19 was mostly mild and the mortality rate in patients with a coinfection of TB and COVID-19 was 10%. The COVID-19 pandemic had a negative impact on TB management under NTEP due to the imposed lockdown. The limitation of this study was the small sample size.

How to cite this article: Sachdeva RA, Verma L, Parashar L, et al. Impact of COVID-19 Coinfection on Management of Tuberculosis Patients registered at DOTS center in a Tertiary Care Hospital. Indian J Respir Care 2023;12(1):17-22.

Source of support: Nil

Conflict of interest: None

Keywords: Antituberculosis treatment, Coronavirus disease 2019, Directly observed therapy, National tuberculosis elimination program.


An outbreak of an influenza-like illness (ILI), COVID-19, caused by a virus named novel coronavirus in Wuhan, was declared by Chinese authorities in December 2019.1 World Health Organization declared it a pandemic on 11th March 2020 because of its rapid spread, morbidity, and mortality.2 The first case of COVID-19 in India was confirmed in the last week of January 20203 and since then has been causing havoc resulting in 4,24,773 deaths to date.4 On 24th March 2020, India declared a strict lockdown5 and one of the consequences was an impact on NTEP.6 The new health crisis caused by the emergent COVID-19 severely impacted the diagnosis, surveillance, and management of TB, as the already overwhelmed healthcare facilities were mainly focusing on COVID-19. This resulted in the nonavailability of drugs and delay in the treatment of TB, and curtailment of its notification.6,10 This study was conducted to evaluate the magnitude of the impact of the pandemic on the management of TB as well as to inspect the profile of increase in morbidity in cases of coinfection of COVID-19 and TB. TB and COVID-19 affect the lungs largely and present with common symptoms like cough, fever, and dyspnoea. The severity, as well as mortality of the COVID-19 among patients with TB, is likely to be higher due to compromised lungs and other comorbidities or living conditions (diabetes, human immunodeficiency virus, smoking, poorly ventilated spaces, etc.) that increase their vulnerability to being chronically debilitated and malnourished.7,10

A history of active as well as latent TB is a significant risk factor for COVID-19 infection. These patients were more susceptible to COVID-19 infection, quick progression, development of severe disease, and poor outcome.7,16 The present study was conducted to evaluate the severity of COVID-19 in these patients and study the impact of COVID-19 on TB outcomes.

In view of the advisory issued by the Government of India, it is important to differentiate these two diseases from each other.6,7 To address the dual stigma being faced by TB patients, it emphasizes bidirectional TB-COVID-19 screening that is, COVID-19 screening for all diagnosed TB patients and TB screening for all COVID-19 positive patients; TB screening for ILI cases and TB screening for severe acute respiratory infection cases.7



The study included patients registered at the DOTS center, ESIC Medical College and Hospital, Faridabad, Haryana, India, from 1st April 2020 to 31st July 2021. The study was conducted with prior approval of the Institutional Ethics Committee. Informed written consent was taken from all patients. Each patient was interviewed telephonically or in person. The consent of the patients who were interviewed telephonically was obtained by mailing the consent performa to their DOTS center. Diagnosis of TB confirmed microbiologically or radiologically by a recognized specialist was accepted. For diagnosis of COVID-19, a positive report of reverse transcription–polymerase chain reaction (RT-PCR) or rapid antigen test (RAT) was acceptable.

The severity of COVID-19 was defined as follows:20

Moderate any one of the following:

Severe any one of the following:

Study Design

This was a retrospective observational study.

The inclusion criteria were as follows:

  • Tuberculosis (TB) patients registered at the DOTS center at ESIC Medical College and Hospital, Faridabad, Haryana, India.

  • Patients registered at the DOTS center who contracted COVID-19, confirmed by RT-PCR or RAT after being diagnosed with TB.

  • Patients registered at the DOTS center, who contracted TB after COVID-19 infection confirmed by RTPCR or RAT.

The exclusion criteria were as follows:

  • Patients who could not be contacted telephonically or patients not willing to participate.

  • Patients with no confirmed diagnostic test for COVID-19 infection.

  • The patients are not able to complete the questionnaire due to any cause.

Data Collection

Each patient was interviewed telephonically or in person. We used a semi-structured predesigned questionnaire to record the data collected from participants who qualified the criteria and consented to the study. We included the sociodemographic profile,21 relevant clinical histories, course of treatment, disease outcome, and vaccination status of Bacille Calmette-Guérin (BCG) and COVID-19 in the study tool. Epidemiological data were analyzed to study the prevalence of COVID-19 and its severity among patients suffering from TB and to study the impact of the pandemic on the management of TB in patients registered with NTEP.

Statistical Analysis

All data were entered into Microsoft Excel 2019 software. Categorical variables were expressed as frequencies and percentages. Continuous variables were presented as mean with standard deviations or median with interquartile range. Data were analyzed using the Statistical Package for the Social Sciences 25th version. Chi-squared test was used for the analysis of qualitative data. Significant p-value < 0.05 (Table 1).

Table 1: Clinical profile of the patients with TB and COVID-19 coinfection
Profile of COVID-19-positive TB patients
COVID-19 positive patient Age(years)/ sex Comorbidity COVID-19 vaccine BCG TB site/status or outcome COVID-19 presentation Severity of COVID-19/ oxygen requirement Hospitalisation/ duration
1 14/female Cardiovascular disease No Yes EPTB/on treatment Symptomatic Mild No
2 18/male Nil No Yes PTB/cured Symptomatic Mild No
3 20/female Lung disease No Yes EPTB/on treatment Symptomatic Mild No
4 22/female Nil No No PTB/cured Asymptomatic Mild No
5 24/male Nil No Yes EPTB/on treatment Asymptomatic Mild No
6 24/male Nil No Yes PTB/on treatment Symptomatic Mild No
7 33/female Nil No No PTB/completed Asymptomatic Mild No
8 35/male Cardiovascular and renal disease No No EPTB/died Asymptomatic Mild Yes/<10 days
9 36/female Nil No No PTB/on treatment Symptomatic Mild No
10 39/male Renal disease No Yes EPTB/completed Asymptomatic Moderate/simple mask Yes/>10 days

EPTB, extrapulmonary tuberculosis; PTB, pulmonary tuberculosis


Out of 387 TB patients registered at DOTS center over the duration from 1st April 2020 to 31st July 2021 in ESIC Medical College and Hospital, Faridabad, Haryana, India, 191 patients participated in the study.

There were 97 (50.7%) females and 94 (49.2%) males, 155 (81.1%) patients were from urban areas, and 36 (18.8%) were from rural areas. A total of 91 (47.6%) patients were between 26 and 50 years of age, 83 (43.5%) were <25 years of age, and 17 (8.9%) patients were of >50 years. A total of 108 (56.5%) patients belonged to the upper-lower (IV) class, 58 (30.4%) patients belonged to the lower middle (III) class, 14 (7.3%) patients belonged to the lower (V) class, and 11 (5.8%) patients belonged to the upper middle (II) class.

Out of all the TB patients, 20 (10.5%) were smokers, 15 (7.9%) had a history of alcohol consumption, and 16 (8.4%) had a history of tobacco chewing. A total of 41 (21.5%) patients had associated comorbidities along with TB, out of which 30 (73.1%) patients had one comorbidity, six (14.6%) had two comorbidities, and five (12.1%) had more than two comorbidities. Out of them, 24 (58.5%) patients had diabetes, 13 (31.7%) patients had cardiovascular disease, six (1.4%) had renal disease, one patient had asthma, and one patient had chronic obstructive pulmonary disease (COPD) (Fig. 1).


Fig. 1: Diagrammatic representation of the number of tuberculosis patients suffering from various comorbidities

Around 111(58.1%) patients were vaccinated with BCG vaccine at birth. A total of 62 (32.4%) patients had received the COVID-19 vaccine, out of which 47 (24.6%) patients had received one dose and 15 (7.9%) patients had received both doses. Out of the 129 (67.5%) patients who were not vaccinated against COVID-19, 49 (25.7%) were <18 years of age, 46 (24.1%) patients were concerned regarding the safety of the vaccine, 26 (13.6%) were willing to get vaccinated but hadn’t registered yet, and six (3.1%) patients were hesitant because of the adverse reactions related to the vaccine (Figs 2 and 3).


Figs 2A and B: Diagrammatic representation of the site of TB in patients who tested. (A) Negative for COVID-19; (B) Positive for COVID-19


Fig. 3: Impact of COVID-19 on the management of TB. A total of 13 patients missed their dose of ATT because of the nationwide lockdown imposed due to COVID-19

Among the patients registered at the DOTS center, 118 (61.8%) had extrapulmonary TB and 73 (38.2%) patients had pulmonary TB; 31 (16.2%) patients had a family history of TB, and 18 (9.4%) patients had a previous history of TB. A total of 98 (51.3%) patients were on ATT, 35 (18.3%) patients were cured, 50 (26.1%) patients had completed their treatment, six (3.1%) patients died, one patient was lost to follow-up, and one patient had stopped the treatment after 1 month. During the lockdown period, eight (4.2%) patients switched to the private sector for their TB treatment.

Three (1.6%) patients had rifampicin-resistant TB, out of which one patient had a previous history of TB for which the treatment was completed.

Out of the 191 patients who participated in the study, bidirectional screening for TB and COVID-19 was done for all patients. Among them, 10 (5.2%) patients tested positive for COVID-19, of which five were symptomatic at the time of presentation and five were asymptomatic.

Two (20%) of them were diagnosed with COVID-19 before being diagnosed with TB and eight (80%) were diagnosed with COVID-19 after they had been diagnosed with TB and were on ATT. Out of these eight patients, two were cured of TB, two had completed their TB treatment, three were still on ATT, and one patient died within a month after COVID-19 diagnosis.

Among the patients who tested positive for COVID-19, none of them was vaccinated against COVID-19, six (60.0%) patients had extrapulmonary TB and four (40.0%) patients had pulmonary TB. Based on the severity of COVID-19 disease, nine patients had a mild infection, of which one had a moderate infection, which required oxygen via a simple face mask.

Eight (80%) patients were in home isolation. Two (20%) patients required hospital admission, of which one patient with a moderate disease was admitted for more than 10 days and one patient had a mild disease but died after a month of hospitalization because of COVID-19-related sequel.

During the pandemic, 29 (15.2%) TB patients missed their dose. In total, 13 patients faced problems either because the center was closed, they could not go to the center, or drugs were not available. Eight patients forgot to take the dose despite having their medication, seven patients had personal reasons that led to delay in visiting the DOTS center, and one patient had migrated.

Out of the total 191 patients, 99% of them followed hand hygiene, 56% followed social distancing guidelines, 91.6% wore a mask in public places, and 33% avoided going outside during the pandemic.


Tuberculosis (TB) is an airborne, bacterial infectious disease spread by respiratory droplets. It is caused by Mycobacterium TB.27 Pulmonary TB is the most common type of TB, accounting for 90% of TB cases.28 It is gradual in onset and the symptoms are progressive.

Coronavirus disease (COVID-19) is an airborne, viral infectious disease transmitted by droplets and fomites. The incubation period is 5–14 days. Studies suggest a period of 5 days as the mean incubation period29 and a period of 3 days as the median incubation period.30 Various studies suggest a higher risk of death for COVID-19 patients with preexisting comorbidities like hypertension, diabetes, and cardiovascular disease, but only a few studies have involved COVID-19 patients coinfected with other respiratory infectious diseases.33

Both COVID-19 and TB, are mainly transmitted by respiratory droplets and target the respiratory system mainly, So the outcome can be worse among patients with COVID-19 and TB coinfection (aptly abbreviated COVID-19 and TB).13,32 Both diseases primarily target the lungs and present with common clinical features like cough, fever, and shortness of breath.7,10,22 It is important to differentiate between these two diseases and make an appropriate diagnosis. Following the advisory issued by the Government of India7 bidirectional TB-COVID-19 screening was done in all the patients.

Our study reveals that COVID-19 occurrence in patients with TB is 5.2%. In a similar study in Ahmedabad, none of the TB patients was infected with COVID-19.12 In the limited number of studies on COVID-19 and TB coinfection, the prevalence of TB among COVID-19 patients was 0.37–4.47%.9 COVID-19 has negatively impacted the clinical development of TB and vice versa.9,14,18,19

Because of the impaired lung function, patients suffering from any preexisting respiratory disease such as TB, asthma, COPD, interstitial lung disease (ILD), bronchiectasis, etc., would be at risk of severe disease and poor outcomes in patients with COVID-19 and TB coinfection. It may lead to acute respiratory distress syndrome, which may progress to respiratory failure and might result in death.

The risk of the severe outcome of COVID-19 in people with preexisting asthma is relatively low. It appears that the patients with COVID-19 and ILD have a high risk of severe disease outcomes, but their risk of death from COVID-19 at the peak of the epidemic was mostly far lower than the ordinary risk of death due to COVID-19.31

The severity of COVID-19 in our study was mostly mild. The results are comparable to a study at an Italian reference hospital where COVID-19 in TB patients was clinically manageable.15

In our study, the mortality rate in COVID-19 and TB coinfection patients was 10%, which can be compared to other studies worldwide with a rate of 11–13%.13,14

Biosocial determinants like poverty, poor hygiene, pollution, overcrowding, and comorbidities are common in both TB and COVID-19.22 In terms of the sociodemographic profile of the patients, our study had female dominance, with most of the patients being between 26 and 50 years of age and least number of patients were of >50 years of age. Around 56.5% of patients belonged to the upper-lower (IV) socioeconomic class.

Various Chinese studies have shown that old age and associated comorbidities are independent risk factors of a poor prognosis of those infected with COVID-1912,16,17 further, TB alone has been associated with a 2–2.5 fold increased risk of severe COVID-19 disease.9,18,19

Various studies indicate that patients in the female subjects, younger age group and without any comorbidity respond better to COVID-19 infection and have a better immune response.23 These results justify the low occurrence of COVID-19 in our study as the major participating population comprised females, the young age group, and with no associated comorbidity.

In our study, 78.5% of TB patients had no other associated comorbidity, and 21.5% had associated comorbidities. In a separate study at an Italian reference hospital, 33% of patients had associated comorbidities15 comparable to another Indian cohort where 27% of TB patients had associated comorbidities.11

In our study, 32.4% of patients had received the COVID-19 vaccination, out of which none of the patients with coinfection had received the vaccine. Both the vaccines developed in India have been proven to confer protection against COVID-19 infection. Moreover, studies have shown that the vaccine protects from the progression of disease severity, and its efficacy is dose-dependent.24,25

Management of COVID-19 was prioritized throughout the country in the year 2020. As the virus spread, COVID-19 dedicated beds in the hospital wards and intensive care unit were increased; and the demand for supplemental oxygen, drugs, diagnostic methods, and other resources increased simultaneously. All existing equipment, finances, infrastructure, and resources under various health programs were redirected to the management of COVID-19. A nationwide lockdown was imposed, leading to disruption of the smooth dispensing of non-emergent healthcare services, including TB.

In 2020 and 2021, the COVID-19 pandemic impacted hugely health, society, and the economy. Essential TB services like national disease surveillance systems, TB diagnosis, notification, and disease burden (incidence and mortality) were impacted. The impact was on access to diagnosis and treatment on both the supply side (e.g., capacity to continue to provide services) and the demand side (e.g., willingness and ability to seek care in the context of lockdowns and associated restrictions on movement, concerns about the risks of going to healthcare facilities during a pandemic, and stigma associated with similarities in symptoms related to TB and COVID-19).26

There were challenges in the smooth implementation of the TB program due to the pandemic. Initially, diagnosis and management of TB were hampered due to changes in the priorities of the healthcare system. Similar presenting symptoms of both diseases and a shift in focus toward COVID-19 might have resulted in the underdiagnosis of TB cases, in turn decreasing the true number of patients that might have suffered from coinfection. The imposition of the lockdown made it difficult for patients to access routine healthcare facilities. Patients could not go to the nearest center to take the next dose of their medication due to transportation issues. At times the center was closed, drugs were unavailable, or non-COVID-19 facilities were at a halt. Patients turned to private healthcare systems to seek treatment.

There have been many apprehensions that ones with previous respiratory diseases are at more risk for COVID-19 infection. This fear may have led to the observance of safety measures religiously by the patients, which helped in reducing their exposure and breaking the chain of disease transmission.

Coronavirus disease (COVID-19) appropriate behavior like social distancing, use of face masks, hand hygiene, strict implementation of lockdown, and practice of self-isolation may have been responsible for decreasing the transmission of TB along with COVID-19.


The limitation of this study was the small sample size.


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