Who Gets Hit the Hardest?
Disease Emergence and Inequality
(and why “America-first” politics will backfire)
Pathogen evolution and disease emergence have been happening for thousands of years, and continue to do so. And even though they can affect all parts of the world, they thrive in conditions of inequality, disproportionately affecting the world’s most vulnerable populations.
Who exactly is most at risk? And how do structural inequalities shape disease spread and public health outcomes? Bottom line: they make things worse for vulnerable populations, but that doesn’t mean that people better-off countries should feel too sheltered from the realities of disease emergence. Let’s take a closer look at the key factors that drive spread and vulnerability to infectious disease outbreaks.
Disease emergence and re-emergence: 2003-2022. Source: UK Governmment.
The Political Ecology of Disease: A Vicious Cycle
Epidemics don’t just cause suffering—they reinforce cycles of poverty, inequality, and marginalization. When disease strikes poor communities, the economic consequences can be devastating. Think about it -- illness and caregiving responsibilities mean missed work and ultimately loss of income. Children frequently needing to miss school has long-term impacts on their education and economic prospects in life. Healthcare costs push families even deeper into financial instability. And it’s not just about countries being poor – it’s about inequality. Income inequality in a country was shown to lead to more deaths during the COVID-19 pandemic.
At the same time, marginalized populations are often disproportionately exposed to infectious diseases. Many work in high-risk jobs—such as in agriculture, street markets, and waste management—where they are more likely to come into contact with infected animals, contaminated water, or disease vectors like mosquitoes and ticks. These realities create perfect conditions for pathogen spillover from animals to humans, increasing the risk of outbreaks. And when things get really bad, like in the case of a pandemic, productivity decreases and households are pushed back into poverty. It’s been shown here.
Access to Healthcare: The Difference Between Containment and Catastrophe
Healthcare access is a determining factor in disease emergence and persistence. In low-income regions, people are far more likely to remain untreated (or not complete treatment), allowing infections to spread. This means more opportunities for pathogens to mutate, which means more chances for a particularly virulent virus or drug-resistant bacteria to evolve and spread in the population. These regions also often face vaccine shortages, leading to unchecked outbreaks.
We saw this during the COVID-19 pandemic, where vaccine hoarding by wealthier nations left many lower-income countries with little access to life-saving immunisation, possibly costing more than a million lives. But these disparities don’t just affect the poor—they allow diseases to evolve in under-vaccinated populations, ultimately increasing the global risk of vaccine-resistant variants.
Pathogens Love Crowded Cities
The future is urban. Cities are growing faster than ever in rapidly developing countries, creating environments where diseases flourish. This is because a lot of urbanisation is happening in the form of slums. These informal settlements are characterised by overcrowded housing, poor sanitation, lack of clean water, and close human-animal interactions. Not only does this make for generally deprived living conditions, but also means respiratory infections like tuberculosis can spread more easily, diarrheal diseases like cholera are difficult to control, and zoonotic spillovers are more likely (as seen with Mpox and Ebola). The bottom line is that as slum populations continue to grow, so too does the likelihood of new infectious diseases emerging.
Rooftops in the district of Airoli in Mumbai, India
Climate Change, Displacement, and Infectious Diseases
The climate crisis is a health crisis. Rising temperatures, extreme weather, and environmental degradation are all part of climate change, and in addition to their direct health impacts, these phenomena are forcing millions to migrate, often into overcrowded and unsanitary living conditions like refugee camps. This means potentially introducing diseases to new populations, but also encountering unfamiliar pathogens to which they have little immunity themselves. Combine this with the fact that migration is increasing in areas simultaneously affected by climate change and violent conflict (such as in Africa and the Middle East), and you have the perfect conditions for disease transmission – worsened healthcare infrastructure, unsanitary and overcrowded living conditions of refugee camps, and logistical difficulties in delivering vaccines and medical treatments.
“The negative impacts of climate change and weather variations have been evident in almost all parts of Nigeria within the last decade, particularly recent floods across several regions.” Source: Mongabay, 2023.
Trump’s Politics: Both Selfish and Self-destructive
1. Cutting Foreign Aid
Foreign aid isn’t “fun money” for its beneficiaries. It funds vaccination programs, clean water initiatives, and disease surveillance in the poorest regions of the world. UNAIDS has warned that withdrawing U.S. support from global AIDS programs could result in 8.7 million new HIV cases and 6.3 million AIDS-related deaths by 2029, all due to treatment disruptions. A lot of this will happen in South Africa (Elon Musk’s home country), which has the most people of any country living with HIV. But cutting this funding will have dire consequences the world over -- resurgence of preventable diseases like measles, polio, tuberculosis, and malaria, as well as unnoticed pathogen emergence have the potential to affect all parts of the world.
Pathogen evolution and disease emergence do not happen in a vacuum; diseases don’t respect political borders. In a globalised world, the cost of response far outweighs the “savings” from cutting aid. Failing to invest in global health today guarantees higher costs and more deaths tomorrow. Which leads us to the next destructive Trump policy move…
2. U.S. Withdrawal from the WHO
The World Health Organization (WHO) is the primary body responsible for early warning systems for emerging diseases, vaccine distribution coordination during outbreaks, and sharing of treatment guidelines during pandemics. By withdrawing from and restricting U.S. Centers for Disease Control (CDC) collaboration (and even communication) with the WHO, the U.S. has weakened global pandemic preparedness—a decision that will ultimately backfire when the next outbreak emerges.
3. Anti-Vaccine Sentiment: A Pathogen’s Best Friend
Make it stand out
People don’t get vaccinated —> herd immunity weakens —> preventable diseases return.
More hosts = more mutations, increasing the risk of vaccine-resistant strains.
Anti-vaccine policymakers like Robert Kennedy, Jr. being assigned to prominent positions such as U.S. Secretary of Health is a gift to pathogens. Pathogen evolution just is a game of basic probability. With viruses, mutation occurs in infected people, so the more people infected with a virus, the more chances we give it to mutate. This means more chances for a more virulent or drug-resistant strain to emerge. In a nutshell:
The Bottom Line: Global Health Security is Collective Security
Outbreak preparedness isn’t about charity—it’s about self-preservation. Addressing global health disparities isn’t just an ethical imperative; it’s a necessity for preventing the next pandemic. It’s a “when,” not an “if,” and the world is too interconnected to take chances. Governments and policymakers should be supporting, not defunding global vaccination programs, disease surveillance, and medical research. They should be strengthening, not weakening international health cooperation.
But what can non-policymakers do? There are still meaningful ways to push back against policies that weaken global health systems:
1. Support Organizations Filling the Gaps
Since government policies may cut funding for global health initiatives, you can support NGOs and institutions that provide vaccines, disease surveillance, and outbreak response by donating or advocating for their work on social media. Some key organizations include:
· Doctors Without Borders – Provides emergency medical care in underserved regions
· The Global Fund – Funds programs to combat HIV, TB, and malaria
· Gavi, the Vaccine Alliance – Ensures vaccine access in low-income countries
· WHO COVID-19 Solidarity Response Fund – Supports pandemic response efforts
2. Push Back Against Anti-Vaccine and Anti-Science Policies
Trump-era policies have emboldened anti-vaccine movements, undermining trust in science. Fight, don’t spread misinformation about vaccines and science-backed treatments by getting yourself and your children vaccinated and encouraging others to do the same. Politely challenge false claims on social media and in conversations -- sharing reliable sources like the CDC and WHO. Vote for pro-science candidates at all levels of government and boycott companies that fund misinformation or anti-science politicians. Sites like OpenSecrets track corporate donations to political campaigns.
3. Advocate for Global Health Funding
Policymakers listen to voters, and public pressure can influence funding decisions. If you’re American, you can call or email your representatives to demand continued funding for USAID, the WHO, and other global health initiatives. And no matter what country you’re from, you can easily sign petitions—platforms like Change.org and Global Citizen often run campaigns to protect global health funding. You can also join local advocacy groups. Organisations like Partners in Health and RESULTS both push for stronger global health policies.
4. Keep Paying Attention
Governments count on public disengagement to pass harmful policies unnoticed. Trump’s administration is explicitly relying on this! Stay informed by following reliable news sources -- The Lancet, NPR, The Guardian’s Global Development section, to name a few. Track policy changes—Websites like KFF Global Health Policy and Devex provide up-to-date insights.
Final Thought:
No action is too small. Global health security depends on grassroots efforts, and individual advocacy can shape the public conversation. Staying informed, speaking up, and supporting science-based initiatives all help counteract policies that put public health at risk
References & Further Reading
Policies to prevent zoonotic spillover: a systematic scoping review of evaluative evidence
Rise of Informal Slums and the Next Global Pandemic
Slum health: Diseases of neglected populations
