Despite being preventable and curable, tuberculosis (TB) remains a persistent health threat across the world. TB is now the number one infectious disease killer worldwide, causing 1.25 million deaths in 2023. As a respiratory infection prone to drug resistance, TB poses a persistent threat to global health security.
Progress against the disease rebounded quickly after the disruptions caused by COVID-19, but recent reductions in development assistance for health pose a serious threat to sustaining this momentum. Many of the most affected countries face significant gaps in funding for tests and treatments. Yet any let-up in the fight against TB will only increase the costs and risks.
TB is an extremely dangerous disease. In 2023, an estimated 10.8 million people fell ill with TB worldwide. In fact, new TB cases have been on an upward trend since 2020. In our hyper-interconnected world, TB can be found in every major city in every country. A person with active, untreated TB can spread the disease to as many as 10 to 15 people in a single year.
The 1.25 million deaths caused by TB in 2023 reflect a fatality rate of almost 12%, far higher than COVID-19. Most of these deaths are avoidable. The vast majority of TB cases are “drug sensitive”, meaning that they can be cured using relatively inexpensive, if somewhat protracted treatment. The primary challenges in fighting this form of TB are to find those who have fallen ill, to get them on treatment and to ensure they complete it. Given that most TB cases occur in poor and marginalized populations, none of these challenges are straightforward to overcome.
Yet there is also a far nastier form of TB. In 2023, an estimated 400,000 people developed different types of “drug resistant” TB, which are much more difficult to treat, and far more likely to cause death. Because drug-resistant TB is hard to diagnose, and so costly and complex to treat, only 2 in 5 people who got drug-resistant TB received treatment in 2023. Not all of those treated survived, and most of those who didn’t, died. Drug-resistant TB is one of the biggest causes of death from antimicrobial resistance.
Looked at through a global health security lens, the nightmare scenario is a serious proliferation in drug-resistant versions of TB, given how hard it is to treat and how deadly it is. This could happen through untreated people with drug-resistant TB infecting others. But it could also happen because people with drug-sensitive TB fail to complete their treatment, allowing the pathogen to resurface in drug-resistant form. We must also recognize that the processes of genetic evolution that produce drug-resistance are always in motion, so the threat of even more resistant or easy to transmit versions of the disease cannot be discounted.
Failing to control TB creates huge risks for everyone. Right now, TB is the “pandemic of the poor”, with most of the deaths occurring in the poorest communities, people living with HIV, or in otherwise marginalized populations, such as displaced people and refugees, prisoners, and those who inject drugs. Stigma and discrimination impede access to life-saving services and exacerbate the vulnerability of such populations. But left unchecked, TB is a threat to us all. Remember that it is less than 100 years since TB was the biggest killer in almost all the rich nations in the world.
In addition to this health security imperative, there is also a compelling economic argument for investing to defeat TB. Given that it disproportionally affects those of working age, and can be costly and complex to treat, TB generates huge costs in terms of lost productivity and health system expenditures. Investments in TB prevention, early detection and treatment yield extremely high returns.
Despite the current turmoil in global health, there are reasons to be optimistic. At the last United Nations High Level Meeting on the Fight Against Tuberculosis, countries reaffirmed their commitment to global targets to end the disease. New innovations promise significant improvements in diagnosis, prevention and treatment. Market-shaping efforts led by global partners working with the private sector are delivering important price reductions in key TB commodities, making lifesaving tools more accessible and affordable. Investments in TB programs are also strengthening health and community systems, making them more inclusive, more resilient and better prepared for other health threats. In 2024, more people were accurately diagnosed and successfully treated for TB than ever before.
This is not the moment to slow down the fight or turn our backs on TB. No, now is the moment to redouble our commitment to defeat the disease – to save millions of lives and to safeguard our collective future. We have the tools, and we know what works. What we need is political will and money.
