As with most lines of progress in various areas of medicine that were underway when COVID-19 emerged, gains in the global fight against tuberculosis (TB) have been threatened as a result of the pandemic. In addition to delays in diagnosis and treatment for individuals with TB, the diversion of resources required to combat COVID-19 also led to disruptions in ongoing TB research and control programs.1
Each year on March 24, the World Health Organization (WHO) commemorates World TB Day to increase awareness and encourage the acceleration of global efforts to eliminate TB. For 2021, the theme of World TB Day is “The Clock Is Ticking” to convey the “sense that the world is running out of time to act on the commitments to end TB made by global leaders.” Since the year 2000, more than 60 million lives have been saved thus far as a result of these endeavors.2
Nonetheless, in 2019 nearly 10 million people fell ill with TB, approximately 1.4 million people died as a result of TB, and 445,000 people fell ill with drug-resistant TB. Staying on track to significantly reduce these numbers is “especially critical in the context of the COVID-19 pandemic that has put the WHO’s End TB Strategy’s progress at risk, and to ensure equitable access to prevention and care in line with WHO’s drive towards achieving Universal Health Coverage.”2
Although the full impact of the pandemic on TB progress remains undetermined, several modeling studies have highlighted the potentially significant impact on TB incidence and mortality in the absence of an adequate response. In a study published in August 2020 in the European Respiratory Journal, results indicated that cumulative TB deaths could increase by as much as 8% to 14% in the next 5 years across China, India, and South Africa alone.3
More recent analyses have produced similar or worse estimates.4,5 Findings from an October 2020 study suggest that even if lockdown requirements result in a 50% decline in TB transmission, a 3-month suspension of TB services could ultimately lead to an additional 1.19 million cases and 361,000 deaths in India alone, with substantial increases in cases and deaths predicted for several other countries as well. “The principal driver of these adverse impacts is the accumulation of undetected TB during a lockdown,” according to Cilloni et al.5
More broadly, disruptions in TB services threaten to undermine commitments to diagnose and treat 40 million patients with TB by 2022 and to administer preventive treatment to 30 million people by then, to include “24 million household contacts of TB patients — 4 million of whom are children under [the age of] 5 — and 6 million people living with HIV.”2 The WHO has called on stakeholders to continue working toward the realization of these goals. Other objectives include sustainable annual financing in the amount of 13 billion dollars to support efforts to end TB, as well as 2 billion dollars for TB research.2
While “short-term disruptions can trigger escalations in TB burden that can take years to return to pre-lockdown levels,” the long-term effect of said disruptions “increases in TB burden could be averted in the short term through supplementary ‘catch-up’ TB case detection and treatment, once restrictions are eased,” wrote Cilloni et al.5
In fact, later this month, the WHO is planning to release guidelines on systematic screening. Systematic screening for TB is “the systematic identification of people at risk for TB disease, in a predetermined target group, by assessing symptoms and using tests, examinations, or other procedures that can be applied rapidly,” according to WHO.2 Early detection and initiation of treatment can improve patient outcomes and reduce associated costs, as well as reducing the prevalence of and preventing more people from developing TB in a community.2
For further discussion regarding TB progress and current challenges, we interviewed C. Finn McQuaid, PhD, assistant professor in the department of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine (LSHTM) in the United Kingdom and co-director of the TB Centre at the LSHTM. Dr McQuaid also co-authored the August 2020 study mentioned above.3
What is the general state of progress in the fight to end TB, and how has the COVID-19 pandemic affected this progress?
In general, we have been making steady progress in the fight to end TB, although this has been much slower than we would like. However, as work by myself and others has shown, the COVID-19 pandemic is likely to have set this progress back by years at the very least, as TB incidence and especially TB mortality are predicted to rise.
What are some of the solutions needed to counter the effect of the pandemic on TB progress?
Some of the solutions are already being implemented, such as provision of additional medicines to patients and the use of digital treatment adherence technologies to support patients in taking their medication, which means patients do not have to attend clinics as often.3,6
As lockdowns ease in various places, another key solution is going to be to actively search for people with undiagnosed TB, as there will likely be a large pool of people who have been unable to access diagnosis for a range of reasons. Because people have, in many cases, been spending significantly more time in their homes and less in communal spaces, a lot of Mycobacterium tuberculosis transmission is likely to have occurred in those homes, so household contact tracing is likely to be particularly important.3
What areas of research should future efforts focus on?
Dr McQuaid: For me, one of the biggest areas to focus on is social determinants. COVID has again highlighted how inequitable the effects of disease can be, and issues like an increase in malnutrition and poverty due to COVID will have long-term repercussions for vulnerability to TB. Tied into this are aspects such as stigma, which is a real issue for TB and may well have worsened due to COVID. I think in TB we are increasingly aiming to be patient-centered in our approaches, and COVID for me has highlighted that, now more than ever, that needs to be our focus.
1. Migliori G, Thong P, Akkerman O, et al. Worldwide effects of coronavirus disease pandemic on tuberculosis services, January–April 2020. Emerg Infect Dis. 2020;26(11):2709-2712.
2. World Health Organization. World TB Day 2021: The Clock Is Ticking. Accessed online March 8, 2021. https://www.who.int/campaigns/world-tb-day/world-tb-day-2021
3. McQuaid CF, McCreesh N, Read JM, et al. The potential impact of COVID-19-related disruption on tuberculosis burden. Eur Respir J. 2020;56(2):2001718. doi:10.1183/13993003.01718-2020
4. Hogan AB, Jewell BL, Sherrard-Smith E, et al. Potential impact of the COVID-19 pandemic on HIV, tuberculosis, and malaria in low-income and middle-income countries: a modelling study. Lancet Glob Health. 2020;8(9):e1132-e1141. doi:10.1016/S2214-109X(20)30288-6
5. Cilloni L, Fu H, Vesga JF, et al. The potential impact of the COVID-19 pandemic on the tuberculosis epidemic a modelling analysis. EClinicalMedicine. 2020;28:100603. doi:10.1016/j.eclinm.2020.100603
6. Dall C. WHO warns of COVID impact on TB services. University of Minnesota Center for Infectious Disease Research and Policy. October 14, 2020. Accessed online March 8, 2020. https://www.cidrap.umn.edu/news-perspective/2020/10/who-warns-covid-impact-tb-services