A Gavi report identifies six major threats to global health in 2026, from epidemics linked to conflicts to the emergence of unknown pathogens. These six priority risks — epidemics linked to conflicts, Marburg virus, Disease X, climate-amplified arboviruses, health disinformation, and budget cuts in development aid — are redefining global surveillance. The central issue revealed by IPPS: diagnostics are the weakest link in pandemic preparedness.
Armed Conflicts: Primary Driver of Epidemic Spread
By certain measures, violence and disputes between and within states are approaching their highest levels since World War II. Conflicts fuel the emergence and transmission of infectious diseases by displacing populations, disrupting healthcare, and breaking supply chains for food, clean water, and medicines.
They can also accelerate the spread of antimicrobial resistance. The degree of conflict’s influence on epidemics depends on local conditions, particularly the capacity to provide health services during conflict and the existing health infrastructure.
Marburg Virus: Geographic Expansion and Enhanced Surveillance
In recent years, Marburg has been detected in more countries, notably in Guinea, Ghana, Tanzania, Equatorial Guinea, Rwanda, and Ethiopia. The recent Rwanda epidemic illustrates the potential scale of this virus: 66 confirmed cases and 15 deaths, representing a fatality rate of 23%.
With fewer than 800 confirmed human cases since 1967, Marburg does not justify massive autonomous investments. Preparedness instead involves strengthening overall health systems: surveillance, laboratory capacity, infection prevention, and community trust. This approach also benefits response against other infectious threats.
Health Disinformation Classified as Global Threat
The 2024 UN report on global risks and the 2026 World Economic Forum report classify disinformation among the most serious global threats. It erodes trust, shapes behaviors, and weakens health systems at a time when vaccine-preventable diseases like measles are resurgent, and when the risk of another pandemic remains.
The 2025 Edelman Trust Barometer report indicates that one in three young adults worldwide express doubts about childhood vaccines and rely more on social media and personal experience than on doctors or scientific data. Artificial intelligence exacerbates the phenomenon: in July 2025, a fake video circulated on Facebook purporting to show a WHO press conference claiming that a proposed pandemic treaty would eliminate human rights protections.
Disease X and Diagnostic Delays
The term describes the next unknown pathogen likely to cause a serious epidemic or international pandemic. Multiple assessments suggest that the world could enter 2026 less well prepared than it was in the immediate aftermath of COVID-19.
An examination of the 100 Days Mission implementation by IPPS in 2024 revealed that preparedness remains uneven across pathogens, with diagnostics and therapeutics significantly lagging behind vaccines. A 2025 global diagnostic gaps assessment by IPPS confirmed this conclusion, identifying diagnostics as the weakest link in pandemic preparedness.
Climate Change and Expanding Arboviruses
Rising temperatures, changing precipitation patterns, and increasing floods are extending the habitats of mosquito vectors, particularly Aedes aegypti and Aedes albopictus. Higher temperatures accelerate the development of adult mosquitoes and shorten virus incubation periods, thus increasing transmission speed.
To address this, WHO’s Global Arbovirus Initiative aims to strengthen surveillance and vector control. The World Mosquito Program deploys mosquitoes carrying the Wolbachia bacterium, which reduces their ability to transmit viruses. Gavi plans to invest $2.2 billion in vaccines for climate-sensitive diseases, including cholera, Japanese encephalitis, malaria, meningitis A, typhoid, and yellow fever.
Budget Cuts: Structural Threat to Global Health
Reductions in development aid constitute a structural threat to health systems in low and middle-income countries. The OECD projects a fall of 9 to 17% in official development assistance in 2025, following a 9% decline in 2024. The WHO estimates that external health aid could be 30 to 40% lower in 2025 compared to 2023.
These cuts have already reduced essential health services by up to 70% in some countries, with job losses among health workers. The scale of reductions threatens hardly-won health gains in low and middle-income countries.
The Diagnostic Urgency Revealed by IPPS
IPPS analysis reveals a critical vulnerability: while vaccines advance, diagnostics remain the Achilles heel of pandemic preparedness. Improving coordination in the diagnostic ecosystem and implementing recommendations from the global diagnostic gaps assessment figure among the four priority actions for 2026.
This diagnostic weakness compromises early detection, a decisive element for containing epidemics before they spiral out of control. The six threats identified by Gavi converge toward this central challenge: detect quickly to respond effectively, in a context where conflicts disrupt surveillance, where disinformation undermines trust, and where budget cuts weaken essential health infrastructure.
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