Why we must prepare for existential threats
By Sanjukta
Mondal, Medical Xpress
Edited by Sadie Harley, reviewed by Robert Egan
The COVID-19 pandemic, which brought the world to a standstill at the start of the decade, showed that containing and neutralizing a disease is only one part of being prepared.
A recent Lancet Commission on 21st Century Global Threats to Health set out to answer the question of what major health threats humanity could face over the next 75 years, from 2025 to 2100.
Rather than zooming in on
individual diseases, the commission cast a wider net, looking at interconnected
dangers that could threaten humanity's health and survival.
The commission identified 17 threats to humanity's future.
Two of them—malicious use of artificial intelligence and nuclear conflict
severe enough to trigger a global nuclear famine—carry a chance of causing
human extinction before the century ends.
The other 15 threats are classified as major catastrophic risks, and
each is expected to inflict more than 1 billion cumulative disability-adjusted
life years (DALYs) of health loss by 2100, with air pollution, antimicrobial
resistance and climate change among the most prominent.
The combination of obesity, poor diet and low physical activity forms the largest driver of preventable health loss worldwide, with 23.1 billion healthy life-years at stake between the plausible worst and best scenarios. These factors ranked as the leading health threat in 154 of the 204 countries evaluated.
Beyond immediate response
The world is facing back-to-back shocks, from the COVID-19
pandemic and geopolitical wars to accelerating climate impacts and sudden cuts
in international health aid. These events have exposed how quickly global
stability can be disrupted. Because most governments and political leaders
operate on short political cycles, global health planning is often reactive:
Societies panic when a crisis hits and aim for an immediate resolution.
Researchers believe this leads to neglect of long-term preparedness once the
threat fades.
The study was commissioned to close a gap in existing
frameworks, which were not equipped for the complex, systemic risks of the 21st
century. It does so by establishing systematic risk assessments that keep
long-term threats on the global health agenda before a crisis strikes.
To see where the world is headed, the study built a
reference scenario using the forecasting tools of the Global Burden of
Diseases, Injuries, and Risk Factors Study (GBD). It assumes that historical
trends in risk factors, demographics, education and economic growth continue
without new action changing their course.
Rather than presenting these threats as an unavoidable catastrophe, the study looks at how much of the resulting health loss could be prevented or reduced through policy action. To measure this, it uses disability-adjusted life years (DALYs), which capture the toll of illness, disability and premature death on human health.
Mapping threat levels
The commission classified hundreds of risks into a
four-level pyramid based on their severity. The highest level consists of risks
with extinction potential, followed by major catastrophic threats, major risks
and causes, and the wider threat landscape.
Obesity and its related diet and lifestyle factors top the
chart as the largest preventable health burden. Low educational attainment and
income inequality follow as the second- and third-biggest drivers of
preventable health loss, a sign of how deeply social conditions shape health
worldwide.
Cutting income inequality could win back an estimated 13.8
billion healthy life-years, and improving education offers an even bigger
opportunity, with a scenario gap of 16.1 billion.
The data also showed that life expectancy will keep
climbing, but healthy life expectancy will rise far more slowly, so people will
spend more of their longer lives with chronic disease and disability.
Climate change adds to the toll, with a gap of 1.89 billion healthy life-years between the best and worst scenarios, driven mainly by rising temperatures and air pollution. Some countries will be hit by these factors more than others. For instance, extreme poverty in sub-Saharan Africa is projected to keep rising until late this century, threatening to stall the region's health progress.
How to prepare for the future?
To break historical cycles of panic and neglect, the report
proposed three structural solutions:
- (a)
establishing dedicated government units equipped for long-term foresight,
prevention, preparedness and population protection;
- (b)
forming government-private partnerships to accelerate funding for the
development and distribution of transformative tools, such as platform
vaccines, new antibiotics, affordable obesity therapeutics and atmospheric
carbon removal; and
- (c)
creating an independent body to monitor global threats to health annually,
regularly update risk data and present findings directly to finance
ministers and national security forums.
Written for you by our author Sanjukta
Mondal, edited by Sadie
Harley, and fact-checked and reviewed by Robert
Egan—this article is the result of careful human work. We rely on readers
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Publication details
Christopher J L Murray et al., The Lancet Commission
on 21st century global threats to health, The Lancet (2026). DOI:
10.1016/s0140-6736(26)01714-9
The Lancet, Rethinking threats to human survival, The
Lancet (2026). DOI: 10.1016/s0140-6736(26)01958-6
Journal information: The Lancet
