In mid-November, the leadership of the U.S. National Institutes of Health argued that the best pandemic-preparedness playbook prioritizes making Americans healthier and more resilient to novel pathogens by reducing their burden of chronic disease. The speech made news for its critique of long-standing preparedness strategies built around rapid development and deployment of countermeasures against novel threats, bolstered by nonpharmaceutical interventions to slow the spread of pathogens.

To be sure, healthier life habits alone cannot constitute an effective, comprehensive preparedness strategy against dangerous new and re-emerging microbes, but reducing the premature burden of obesity, diabetes, cardiovascular disease, and other noncommunicable diseases (NCDs) would certainly help—and not just in the United States.

NCDs Will Worsen Most Pandemic Outcomes

The prevalence of NCDs—in particular, obesity, hypertension, cardiovascular disease, and diabetes—significantly affected COVID-19 outcomes and is likely to do the same for many other emerging health threats.

Obesity was a particularly strong determinant of severe COVID-19 infection

Obesity was a particularly strong determinant of severe COVID-19 infection, and pre-existing conditions such as diabetes, hypertension, and obesity contributed to increased risk of hospitalization, intubation, and death. A 2022 Lancet study estimated that if every nation had the same average body mass index (BMI) as a nation at the twenty-fifth percentile for obesity globally, COVID-19 deaths would be reduced by more than 10% globally. That reduction would have been much larger in the United States, where 42% of the population is obese according to the U.S. Centers for Disease Control and Prevention.

Extensive research, summarized in the table below, suggests that NCDs are likely to worsen many pandemic threats, including those most worrisome such as influenza and respiratory infections. The CDC warns that adults with chronic health conditions such as asthma, heart disease, stroke, diabetes, liver disorders, lung diseases, and kidney disease are at higher risk of serious flu complications, hospitalization, and death. Additionally, researchers have found that among U.S. cancer patients, influenza poses four times the risk of death and up to 10 times the risk of hospitalization relative to the general population. NCD risk factors, such as obesity and smoking, have also been linked to more severe influenza outcomes and higher risk of infection among adults.

Noncommunicable Diseases and Adverse Outcomes with Pandemic Threats

The table details research on the risk relationship between NCDs and infectious diseases by year published

The Premature Burden of NCDs in Lower-Income Countries Continues to Rise Rapidly

The United States is not alone in facing "the severe chronic-disease crisis" that the NIH directors reference. NCDs are increasing rapidly among working-age populations in poorer nations that are ill-equipped to handle shifting health-care demands.

Cancers, diabetes, cardiovascular diseases, and other NCDs represent the majority of premature (under age 70) death and disability in every region, including sub-Saharan Africa. The transition from infectious diseases to noncommunicable diseases in lower-income countries is occurring, and is expected to persist, at an unprecedented rate. In the last decade alone, premature NCD deaths grew 40% to 60% in sub-Saharan African nations and reached 111% in Ivory Coast. Central and South Asian nations showed upticks between 25% and 50%, propelled by diabetes and chronic respiratory diseases.

Health Risks in Low- and Middle-Income Countries: 1990–2023

This escalation has three main drivers: population size, age structure, and changes in age-standardized mortality rates from diabetes, cancers, and other NCDs. More people are surviving into adulthood in low-income nations, as child mortality has plummeted over the last two decades because of expanded access to pediatric immunization, improved nutrition, and life-saving interventions such as bed nets and antiviral treatment. Fertility rates are falling alongside these improvements in child survival, but not as rapidly in parts of Africa. Thus, the working-age adult population (ages 20 to 64) in Africa will roughly double from around 883 million in 2024 to 1.6 billion by 2050. As populations in poorer nations grow and as more of those individuals reach their fifth and sixth decades of life, they will develop the chronic health conditions that tend to emerge in late adulthood. As the figure below shows, the combination of aging populations and population growth is the primary driver of NCD increases in most regions of the world.

Change in Premature Deaths by Super Region, 1990–2023

The story does not end there. While declining child mortality represents clear progress, the pattern observed in wealthy nations—where pediatric health improvements led to corresponding modest adult health gains—has not materialized in low-income countries. A 2018 analysis found that a 15-year-old in an average low-income country had the same life expectancy as a 15-year-old in that same country in 1990, even when controlling for HIV/AIDS. This stagnation is due largely to the rise of chronic diseases—and occurring despite dramatic advances in NCD treatment over recent decades: low-cost hypertension control such as dietary changes and exercise, GLP-1 drugs for obesity, and improved prevention strategies for many cancers. Improvements in preventing and treating NCDs are not keeping pace with the growth of the adult population most susceptible to developing chronic conditions such as diabetes and hypertension, particularly in South Asia, Latin America, the Caribbean, and sub-Saharan Africa.

Economic growth has brought substantial benefits to developing nations, improving sanitation, reducing poverty, and increasing food production. However, it has reshaped health risks. High blood pressure prevalence, poor diet, and tobacco use have climbed. Tobacco remains a major risk factor, and unhealthy diets and physical inactivity increasingly drive cardiovascular disease, diabetes, chronic respiratory disease, and cancer. Urbanization, pollution, rising incomes, and aggressive fast-food marketing have contributed to these trends.

Percent Change in Premature Deaths, 2011–23

Obesity rates are increasing rapidly in many regions, including sub-Saharan Africa, diminishing lifespans and substantially affecting quality of life for approximately 2 billion people. Obesity prevalence levels (BMI over 30) in many sub-Saharan African, Central Asian, and Middle Eastern nations already exceed rates in Europe. By 2030, nine countries in these regions are projected to have obesity rates exceeding 40%, a mark comparable to the United States. By 2050, that number is expected to increase to 19 nations.

Current and Projected Obesity Prevalence: 2021, 2030, and 2050

Many low- and middle-income countries (LMICs) are ill-prepared for the demands that a rapid transition to NCDs will place on their health systems. Historically focused on acute care for infectious, maternal, and neonatal diseases, these systems lack the infrastructure for the preventive or chronic care that many NCDs require. Unlike infectious diseases such as HIV or malaria, almost all NCD care in LMICs is paid for by government health expenditure and by patients out of pocket.

Yet these countries are poorer and spend much less on health care than wealthy nations did when their needs became dominated by chronic health conditions. In 2021, an average of $92 per person was spent in sub-Saharan African nations on health, roughly one-fifth of the next lowest-spending region—North Africa and Middle East ($379). More concerningly, health spending is projected to decline rather than increase as sub-Saharan African nations struggle to keep up with population growth and aging. Projections call for the region's per capita health spending to fall to $86 by 2050.

Incorporating Chronic Disease into Pandemic Preparedness and Response

The COVID-19 pandemic revealed that many countries are not equipped or able to effectively respond to emerging diseases. Improving responses to the next dangerous pathogen depends on understanding which capacities most effectively enable countries to prevent, detect, respond, and withstand epidemics and pandemics—and on investing adequately in those capacities before the next regional or global emergency. Clearly, early and adequate access to effective countermeasures, including vaccines, is critical. Estimates show that COVID-19 vaccines saved between 2.5 million and 14.4 million lives in just the first year of the pandemic alone.

On the other hand, most of the more than a dozen studies and reports that have assessed the association between COVID-19 health outcomes and the leading country-level metrics of pandemic preparedness, including the Joint External Evaluation and the Global Health Security Index, have found no association. Having good capacity, as measured by those metrics, was not only insufficient during the COVID-19 pandemic but unnecessary. Countries that ranked low on these metrics still performed well, even when accounting for factors such as age and income. Nevertheless, international funding for pandemic preparedness continues to be guided by these metrics [PDF].

Development Assistance for Health by Focus Area: 1990–2025

By contrast, international programs addressing chronic diseases such as diabetes, obesity, and hypertension remain underfunded despite being strongly associated with poor outcomes from pandemic threats, being treatable or preventable, and representing more than half the premature (under age 70) burden of death and disability in low- and lower-middle-income nations. Just 4% ($1.1 billion) of overall foreign assistance for health is targeted at NCDs. That figure has only modestly improved over the last 15 years, despite four UN General Assembly special meetings devoted to NCDs.

It need not be this way. Low-cost interventions exist that could leverage existing U.S. global health platforms: primary and secondary prevention of cardiovascular disease; tobacco control; hepatitis B vaccination; nutrition labeling and taxes on sweetened beverages; and human papillomavirus (HPV) vaccination and cervical cancer screening. With imminent generic entry of GLP-1 medications, expanded access to these drugs could be vital in stemming the global obesity crisis in low- and middle-income nations.

As conveyed in the interactive below, if poor nations could achieve premature mortality rates that high-income nations had reached prior to the first UN General Assembly meeting on NCDs, it would save tens of millions of lives and make the world safer from the next pandemic threat.

Premature Deaths Caused by Noncommunicable Diseases

If dedicated interventions enabled low- and middle-income countries to avoid premature deaths at the same rate as high-income countries, tens of millions of lives could be saved

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AJ Mitchell

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