Tuberculosis has such a grip on the world that it has overtaken COVID-19 to once again become the deadliest infectious disease on the planet.
The World Health Organization says TB returned to being the world's leading infectious disease killer in 2023, surpassing COVID-19. It was also the leading killer of people with HIV and a major cause of deaths related to antimicrobial resistance.
"The fact that TB still kills and sickens so many people is an outrage, when we have the tools to prevent it, detect it and treat it," Dr. Tedros Adhanom Ghebreyesus, WHO Director-General, said in a statement. "WHO urges all countries to make good on the concrete commitments they have made to expand the use of those tools, and to end TB."
Tuberculosis is an infectious disease caused by bacteria that most often affects the lungs. It spreads through the air when people with TB cough, sneeze or spit. TB is preventable and curable. Most people with TB infection don't feel sick and aren't contagious. Only a small proportion of people who get infected experience symptoms, which might not appear for months. Symptoms include prolonged cough (sometimes with blood), chest pain, weakness, fatigue, weight loss, fever and night sweats.
In 2023, an estimated 10.8 million people fell ill with TB worldwide, of which 55% were men, 33% were women and 12% were children and young adolescents, according to the WHO's Global Tuberculosis Report 2024. It's the highest number recorded since WHO began global TB monitoring in 1995.
The TB incidence rate (new cases per 100 000 population per year) is estimated to have increased by 4.6% between 2020 and 2023, reversing declines of about 2% per year between 2010 and 2020. A significant number of new TB cases are driven by five major risk factors, according to the report: undernutrition, HIV infection, alcohol use disorders, smoking (especially among men), and diabetes.
Globally in 2023, TB caused an estimated 1.25 million deaths.
Eight countries accounted for more than two thirds of the global total: India, Indonesia, China, the Philippines, Pakistan, Nigeria, Bangladesh and the Democratic Republic of the Congo. The top five countries accounted for 56% of the global total.
Globally in 2023, the reported number of people newly diagnosed with TB was 8.2 million, up from 7.5 million in 2022 and far above the levels of
5.8 million in 2020 and 6.4 million in 2021.
The WHO noted that those newly diagnosed in 2022 and 2023 probably included a sizeable backlog of people who developed TB in previous years, but whose diagnosis and treatment was delayed by COVID-related disruptions.
The report indicates that there is still a large global gap between the estimated number of people who fell ill with TB and the number of people newly diagnosed, with approximately 2.7 million people not diagnosed with the disease, or not officially reported to national authorities in 2023, down from around 4 million in both 2020 and 2021 and below the pre-pandemic level of 3.2 million in 2019.
Globally, an estimated 400,000 people developed multidrug-resistant or rifampicin-resistant TB infections (MDR/RR-TB) in 2023. The number of people diagnosed with MDR/RR-TB and started on treatment was 175,923 -- a slight decrease of 1.1% from 177,912 in 2022 and below the pre-pandemic level of 181,533 in 2019.
In 2023, treatment success rates for drug-susceptible TB sustained at 88% and for MDR/RR-TB was improved to 68%.
Globally in 2023, TB preventive treatment was provided to 4.7 million people. Since 2000, efforts to combat TB have saved an estimated 79 million lives worldwide.
At the same time, global funding for TB prevention and care decreased further in 2023 and remains far below target, the WHO said. TB research also remains severely underfunded with only one-fifth of the $5 billion annual target reached in 2022.
"We are confronted with a multitude of formidable challenges: funding shortfalls and catastrophic financial burden on those affected, climate change, conflict, migration and displacement, pandemics, and drug-resistant tuberculosis, a significant driver of antimicrobial resistance," said Dr. Tereza Kasaeva, Director of WHO's Global Tuberculosis Program. "It is imperative that we unite across all sectors and stakeholders, to confront these pressing issues and ramp up our efforts."