Many TB cases may have gone undetected in prisons in Europe and the Americas during COVID-19

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Contact:
Jillian McKoy, jpmckoy@bu.edu 

Michael Saunders, msaunder@bu.edu 

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Many TB Cases May Have Gone Undetected in Prisons in Europe and the Americas During COVID-19

A new study found that reported diagnoses for tuberculosis were consistently lower than expected throughout the pandemic, even though incarceration rates remained largely consistent and TB detection among the general population managed to reverse after an early-pandemic decline. 

Incarcerated populations have a high risk of developing tuberculosis (TB), with past research suggesting that this burden could be as much as 10 times greater than the general population. 

But during the COVID-19 pandemic, reported TB cases among incarcerated people in Europe and the Americas were much lower than expected, according to a new study led by Boston University School of Public Health (BUSPH) and the London School of Hygiene and Tropical Medicine (LSHTM). 

Published in The Lancet Public Health, the study found that tuberculosis diagnoses plummeted as much as 100 percent in Central and North America in 2021, and nearly 87 percent in Western Europe in 2022 (compared to expected levels). This pattern was distinct from tuberculosis diagnoses among the general population, which experienced a decline in 2020, but generally began increasing again in subsequent years. 

Incarceration levels, meanwhile, remained largely consistent from 2020-2022, suggesting that the reduction in reported TB cases was likely due to other factors, such as reduced capacity for prisons to test and diagnose TB during the unprecedented global crisis.

People with undetected and, therefore, untreated TB are at greater risk of spreading the disease to people they encounter, progressing to severe forms of the disease, and dying. With at least 11 million people incarcerated each year, disease spread and detection in carceral settings has implications for incarcerated people, as well as the wider communities.  

“When countries are unable to detect tuberculosis in high-risk populations—such as people who are incarcerated—it increases the risk of transmission, both within prisons and to the broader community, when people are released from prison,” says Amy Zheng, a PhD student in the Department of Epidemiology at BUSPH and co-lead author of the study, along with Dr. Lena Faust, a postdoctoral fellow at LSHTM. 

Prior to the pandemic, health disparities between prisons and the general population were already vast, and the pandemic widened these inequities even further, Zheng says. “Investing in healthcare systems within prisons is critical to diagnose and treat tuberculosis, ultimately protecting both the individuals incarcerated and the public.”

TB has returned to being the world’s deadliest infectious disease (after COVID-19 took the leading spot for three years), causing 1.25 million deaths worldwide in 2023. A bacterial infection that is usually found in the lungs, it is treatable and preventable, but, without treatment, it has a death rate of nearly 50 percent. While the US has one of the world’s lowest rates of the disease, experts say rising global TB rates could also lead to an increase in TB in the US—which is already experiencing an unusual outbreak of the disease in Kansas.

The study is the first to assess how the pandemic affected TB detections among incarcerated people in multiple countries.

For the analysis, Zheng and colleagues worked with the World Health Organization, Pan American Health Organization, and European Centers for Disease Control and Prevention, ​​utilizing international TB reporting data to examine TB detection trends among people who were incarcerated from 2010 to 2022 in 47 countries in Europe and the Americas. This study sample represented almost five million incarcerated people annually, or 42 percent of the world’s incarcerated population. Using novel modeling, the team calculated the differences between observed and predicted reported TB cases, case rates in prisons, and prison populations.

The researchers were surprised to find that incarceration levels remained consistent (and in some countries, increased) throughout the pandemic. 

“Our prior thinking was that incarceration dropped during the early stages of the pandemic due to decarceration efforts to prevent COVID-19 transmission,” Zheng says. “We were also surprised to see that tuberculosis diagnoses continued to be missed in 2021 or 2022.”

The 10 countries that reported the largest percentage decrease between observed and expected TB diagnoses were Slovakia, Czech Republic, El Salvador, Bulgaria, Belgium, Azerbaijan, Armenia, Romania, Uruguay, and Ukraine.

These results come at a time of international apprehension among health advocates and aid groups, as they scramble to respond to the Trump administration’s massive funding cuts and dismantling of the US Agency for International Development (USAID), which provided substantial funding towards the global TB response, primarily to governments with high rates of the disease. According to the WHO, global efforts to fight TB have saved about 79 million lives since 2000. A digital tracking tool that estimates the real-time effects of the USAID funding cuts on TB worldwide has estimated that (as of Monday, March 31), the cuts have contributed to more than 15,000 additional TB cases and more than 12,000 TB deaths. 

“Recent federal cuts to USAID funding and programming have already significantly impacted tuberculosis control and will severely harm the progress made to reduce tuberculosis globally over the past few decades,” says the study’s senior and corresponding author Dr. Leonardo Martinez, assistant professor of epidemiology at BUSPH. “Future studies will be necessary to better understand how these funding cuts may negatively affect tuberculosis control in prisons.”

The researchers remain concerned that this loss in funding threatens to reverse the global goal to end TB by 2030, and urge the US and international governments to prioritize TB screening and diagnoses among historically neglected populations.

“Given the current disruption in funding, achieving the 2030 global goals to end the tuberculosis epidemic may no longer be feasible,” Zheng says. “As a result, the tuberculosis field must come together globally and regionally to set new, realistic targets and identify new, alternative funding mechanisms to reach those targets.” 

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About Boston University School of Public Health 

Founded in 1976, Boston University School of Public Health is one of the top ten ranked schools of public health in the world. It offers master's- and doctoral-level education in public health. The faculty in six departments conduct policy-changing public health research around the world, with the mission of improving the health of populations—especially the disadvantaged, underserved, and vulnerable—locally and globally.