The latest report on tuberculosis from the World Health Organization (WHO) shows that the negative trends that began with the COVID-19 pandemic continue.
The 2022 Global TB Report, released today by the WHO, shows an estimated 10.6 million people fell ill with TB in 2021, an increase of 4.5% from 2020 and the first time in nearly two decades that the number of people sickened by the respiratory disease globally has increased. TB deaths were also up in 2021, rising to 1.7 million from 1.6 million in 2020.
Additionally, 2021 saw the burden of drug-resistant TB increase by 3% from 2020, with 450,000 cases of multidrug- or rifampicin-resistant (MDR/RR)-TB reported.
The increased number of cases and mortality are linked in part to the reduction in essential TB services that has occurred since the pandemic began in 2020. In many high-burden countries, the combination of pandemic lockdowns and the shifting of health resources to the COVID-19 response has resulted in fewer people with TB getting diagnosed and treated, and fewer having access to preventive treatment that can keep the disease from spreading.
In the years prior to the pandemic, though TB was still the world's leading infectious disease killer (a title it has ceded to COVID-19), incidence and deaths had been steadily declining.
"This is a pivotal moment for the global fight to end tuberculosis," WHO Global TB Programme Director Tereza Kasaeva, MD, PhD, said at press briefing. "The COVID-19 pandemic, coupled with ongoing crises such as armed conflict, increasing food insecurity, and political and economic instability, has reversed years of progress."
Large drop in notified cases
The impact that COVID-19 has had on essential TB services is reflected by a comparison with pre-pandemic numbers.
In 2019, the reported number of notified cases—people newly diagnosed with TB and reported to national authorities, a number that signifies a TB case has been documented and the patient is receiving treatment—was 7.1 million, up significantly from 2017. But that number fell to 5.8 million in 2020, with a partial recovery to 6.4 million in 2021.
The report estimates that as many as 4 million people who fell with TB in both 2020 and 2021 were not reported and as a result have gone undiagnosed and untreated, which can lead to increased transmission, increased incidence (after a lag period), and deaths. Timely TB diagnosis and treatment is important because the treatment regimen has a success rate of 85%, according to the WHO.
The number of people receiving preventive treatment was 3.5 million people in 2021, a rebound from 3.2 million 2020 but still below pre-pandemic levels.
"COVID-19 disruptions have severely impacted access to essential TB services, with far fewer people being diagnosed and treated, or being provided with preventive treatment," Kasaeva said.
Most of the people who developed TB in 2021 were in the WHO regions of South-East Asia, Africa, and the Western Pacific, with 30 high-burden countries accounting for 87% of cases. Among the high TB burden countries that saw major shortfalls in TB notifications in 2020 and 2021 were India, Indonesia, China, Myanmar, and the Philippines. Those five countries accounted for 90% of the reduction in case notifications in 2021 compared with 2019.
Kasaeva also highlighted drug-resistant TB as a public health crisis. In addition to the reported increase in cases of resistant TB, which rose in 2021 in four of the six WHO region, she noted that treatment for MDR/RR-TB has declined since the beginning of the pandemic, with only 161,746 patients—roughly 1 in 3 of those in need—receiving treatment.
In 2020, the pandemic was associated with a 15% decline in the number or people enrolled on treatment for drug-resistant TB. Enrollment numbers only partially recovered in 2021.
Some gains, but lack of funding remains an issue
There is some encouraging data in the report. Among the notable gains is that TB preventive treatment reached more than 10 million people living with HIV, surpassing the 2018-2022 global target of 6 million. That's significant because HIV patients have an increased risk of TB infection.
In addition, the report notes increased uptake of rapid diagnostics, all-oral drug-regimens for MDR/RR-TB, and shorter regimens for MDR/RR-TB. The shorter regimens, which were used in 92 countries in 2021 (up from 65 in 2020), have a higher success rate and have cut the treatment time from as long as 24 months down to 6 months.
And while TB incidence increased globally and in five of six WHO regions in 2021, it fell in the African region, which was less impacted by COVID-19 disruptions. Since 2015, TB incidence in Africa has fallen by 22%, which means the region surpassed the first major milestone of the WHO's End TB strategy—a 20% reduction in incidence in 2020 compared with 2015. TB incidence in Europe in 2021 was 25% lower than 2015.
But the funding needed to meet the End TB strategy's ultimate goal of an 80% reduction in global TB incidence by 2030 has also taken a hit amid the pandemic. Already well below the 2022 goal of $13 billion, global annual spending on essential TB services fell from $6 billion in 2019 to $5.4 billion in 2021. And most of the funding for these services (79%) comes from domestic sources.
Cheri Vincent, MPH, head of the TB Division at the US Agency for International Development, which is the largest bilateral donor to international TB efforts, said the countries that have less donor funding for TB and were already struggling with the disease are the countries where the pandemic has had the biggest impact in TB services. Calling it an "equity issue," she said she hopes the report will motivate international donors to help those countries.
"We need to make sure this doesn't happen again," Vincent said during the briefing. "This is a curable disease, and we shouldn't have anyone dying of TB in this day and age."
Advocates for TB treatment and prevention say they hope the findings of the report will convince global leaders that they should make TB a higher priority.
"Despite gains in areas like preventative therapy, we are still behind in just about every pledge and goal regarding TB," Mel Spigelman, MD, TB Alliance President and CEO, said in a statement. "We hope this year’s WHO TB report can provide a catalyst for the entire world to finally embrace the need to end TB."