Conflict-associated disease outbreaks are emerging as the most immediate global health threat in 2026, according to a new insight paper by Gavi, the Vaccine Alliance, which warns that violence, climate change, funding cuts, misinformation, and emerging pathogens are converging to strain fragile health systems worldwide.
“These are challenging times for global health,” the paper states. From conflict-related disease outbreaks and rising health misinformation to climate change and global health funding cuts, the risks to our collective global health are growing, and can feel overwhelming.”
Conflict-associated outbreaks
“By some measures, violence and disputes between and within states are approaching their highest levels since World War II,” the report notes, adding that conflict “drives the emergence and transmission of infectious disease by displacing populations, disrupting healthcare delivery and breaking supply chains for food, clean water and medicines. It can also accelerate the spread of antimicrobial resistance.”
Carrie Nielsen, immunisation lead at the International Federation of Red Cross and Red Crescent Societies, cautions that context matters: “A lot of factors contribute, including environmental conditions, the ability to deliver health services during the conflict, and pre-conflict health infrastructure and immunisation coverage.”
Cholera illustrates the scale of the danger. “More than 6,000 people died from the disease in 2024 – around 50% more than in 2023 – while the number of affected countries rose from 45 to 60,” the paper says, noting that “the current surge has been worsened by disruptions to surveillance and response in conflict-affected areas including parts of Sudan and the Democratic Republic of the Congo.”
“In areas affected by conflict, when people are being displaced, it can be difficult to provide basic services and prevent the disease spreading,” says Allyson Russell of Gavi’s Outbreaks and Global Health Security team.
In response, vaccine production has ramped up. “Global production of oral cholera vaccine has increased from around 30 million doses in 2022 to 80 million in 2025,” the paper notes. Gavi is also introducing “a new agile funding tool – the Gavi Resilience Mechanism (GRM) – designed to respond rapidly to unexpected health emergencies and humanitarian crises that are not covered through existing mechanisms.”
Climate change and arboviruses
The second major threat is climate change, which “is reshaping the geography of diseases caused by arboviruses – those spread by mosquitoes and other arthropods.”
Ignacio Esteban, Senior Manager in Gavi’s Policy team, says: “This is leading to more outbreaks of diseases including malaria, yellow fever, chikungunya and dengue.”
Temperature plays a critical role. “When temperatures rise, mosquitoes become adults more quickly, and the incubation period of the viruses within mosquitoes is shorter, which increases the speed of transmission of these viruses to humans,” says Diana P. Rojas, infectious disease epidemiologist of the WHO Global Arbovirus Programme and co-lead of the Global Arbovirus Initiative.
The impact is already visible. “In 2024 – the warmest year on record – more than 14.4 million dengue cases were reported globally, more than double the previous peak in 2023,” the paper says.
Extreme weather compounds the threat. “After a rainy season, when there are floods or when people collect water because of drought, there will be more breeding sites for mosquitoes, and then those places are more likely to have dengue or other arbovirus outbreaks,” Dr Rojas adds.
Global health funding cuts
The third threat identified is shrinking international aid.
“The scale of the cuts is already threatening hard-won health gains across low- and middle-income countries (LMICs), and the full impact will become clearer in 2026 as countries try to mobilise alternative funding,” the paper warns.
It cites projections that official development assistance “will fall 9–17% in 2025, after a 9% drop in 2024,” while “external health aid could be 30–40% lower in 2025 than in 2023.”
Survey data from 108 LMICs shows “funding cuts have already reduced critical health services by up to 70% in some countries, with job losses among health workers and disruptions to training.”
To counter this, “vaccine financing will be simplified to give countries more flexibility in how they run immunisation programmes,” under the Gavi Leap initiative, while the WHO-led 3 by 35 Initiative calls for higher taxes on tobacco, alcohol and sugary drinks to build domestic funding streams.
Health misinformation
“Health misinformation is becoming one of the most destabilising forces in global health,” the report says bluntly.
“It erodes trust, shapes behaviour and weakens health systems at a time when vaccine-preventable diseases such as measles are resurging, and the risk of another pandemic remains.”
The report notes that “one in three young adults worldwide feels uncertain about childhood vaccines and relies more on social media and personal experience than on doctors or scientific evidence,” citing the 2025 Edelman Trust Barometer Special Report: Trust and Health.
Artificial intelligence is accelerating the spread of falsehoods. “The growing use of deepfakes in health disinformation shows how quickly false narratives can now be created and spread,” it says, referencing a fake video purporting to show a WHO press conference falsely claiming that a pandemic treaty would “remove human rights protections and impose mass surveillance and censorship.”
Still, efforts are under way. WHO’s Africa Infodemic Response Alliance tracks misinformation trends, while Gavi and WHO are working with tech companies “to promote reliable information online.”
Marburg virus disease
Marburg virus disease, though unlikely to trigger a global pandemic, remains a regional danger.
“Marburg virus disease is not a global threat per se, based on current understanding of the virus,” says Anaïs Legand, Technical Officer for Viral Haemorrhagic Fevers at WHO. “However, outbreaks can still have severe economic and social impacts in affected countries.”
The report stresses that “preparedness – especially early detection and resilient health systems – will determine whether future cases remain contained or escalate.”
“The worry is that right now, we don’t have sufficient data to understand exactly which are the places at risk in every country with Rousettus bat presence, limiting ability to reduce bat-to-human exposure and prevent spillover events,” Legand says.
Disease X
Finally, the paper revisits the spectre of “Disease X” – shorthand for the next unknown pathogen with pandemic potential.
“When global health experts refer to Disease X, they are not predicting a specific virus or date. The term describes the next unknown pathogen with the potential to spark a serious international epidemic or pandemic.”
While “2026 is not inherently more dangerous than other years,” the paper cautions that “the world may be entering it less prepared than in the immediate aftermath of COVID-19.”
Dr Maria Van Kerkhove, interim Director of WHO’s Department of Epidemic and Pandemic Management, highlights influenza risks: “The possibility of such a reassortment sparking the next pandemic is strong.”
A 2024 review of the 100 Days Mission found that “preparedness is uneven across pathogens, with diagnostics and therapeutics lagging far behind vaccines,” while a 2025 Global Diagnostics Gap Assessment identified diagnostics as “the weakest link in pandemic preparedness.”
The warning is clear: without “sustained funding and political commitment,” the systems built after COVID-19 “may not be strong enough when Disease X emerges.”
Together, the six threats underscore a fragile moment for global health in 2026 — one in which conflict remains the accelerant, climate the multiplier, funding the constraint, misinformation the destabiliser, and emerging pathogens the ever-present risk.
This story is done in collaboration with First Check, which is the health journalism vertical of DataLEADS