Somewhere in a Lagos market, tilapia is arranged on a shelf in the midday sun without any refrigeration, and a fan a few feet away is doing very little. A suspicious strain of Listeria that was removed from a shipment of leafy greens is being subjected to whole genome sequencing by technicians in a Dutch cold storage facility a few thousand miles north. The contrast is almost too sharp. However, it accurately depicts the current state of the global food system, which is both dangerously exposed in one area and brilliant and sophisticated in another.
There isn’t just one outbreak or one villain in the current pathogen crisis, though it’s reasonable to refer to it as such despite the term’s unsettling connotations. Researchers have been cautioning about this gradual build-up of pressures for years. Microbial growth is being accelerated by climate change. Livestock waste is washing into water systems due to flooding. Wild animals are being forced into agricultural areas due to deforestation. Additionally, a supply chain that prioritizes just-in-time delivery, speed, and connectivity is performing under pressure like any brittle system. It shifts issues more quickly than it resolves them.
This includes aspects of rising temperatures that don’t always make headlines. Warmer temperatures encourage the growth of pathogens like Salmonella and E. coli, which multiply more quickly, reach hazardous concentrations earlier, and endure longer on food surfaces. As temperatures and humidity rise throughout tropical regions, aflatoxins—carcinogenic substances produced by a fungus that colonizes peanuts and maize—become more prevalent. These aren’t speculative dangers that could be found in a research paper. They are currently present in crops, water, and food that is being transported across international borders.
The architecture of the contemporary food trade makes this especially challenging to contain. Produce that is contaminated does not remain in one nation. It shifts. Before anyone makes the connection, it travels through ports, processing plants, distribution centers, and retail shelves in several different jurisdictions. According to WHO estimates, contaminated food causes 600 million illnesses and 420,000 deaths worldwide each year. If current conditions continue to develop as they are, that number might appear modest in ten years.
Food trade routes are only one aspect of the “flyways” issue. Highly pathogenic avian influenza strains are now spread by bird migration corridors, which are the historic routes that species travel across continents. At shared water sources, domestic poultry and wild aquatic birds, which harbor these viruses with minimal symptoms, mix. Scientists are still mapping how these migration patterns are changing due to climate shifts. The issue is not hypothetical. In recent years, avian flu outbreaks have already resulted in significant losses for the poultry industries in North America, Europe, and Asia, and every outbreak report quietly raises the possibility of a strain that could continue to spread to humans.
Additionally, there is the issue of deforestation, which is often presented as an environmental problem but is actually more of a pathogen problem. Fruit bats, rodents, and primates lose their habitat when forest cover disappears. They get closer to livestock operations, farms, and villages. This type of encroachment—climate-driven changes in bat ranges pushing spillover events closer to human populations in South Asia—has been directly linked to the Nipah virus, which has a death rate that makes COVID-19 seem insignificant. Similar trends have been observed in West African Ebola outbreaks. These are not one-off occurrences. They follow a pattern.
The real threat to global food security, according to research published earlier this year by Oxford, is compound shocks, which include a bad harvest combined with a trade disruption, an increase in energy prices, and a disease outbreak all at the same time. According to the model they created, almost every nation in the world experiences food security losses simultaneously, albeit not equally, in worst-case compound scenarios. The shock is better absorbed by nations with diverse supply chains and sufficient grain reserves. The hardest-hit nations are those that rely on concentrated suppliers and are already on the verge of food insecurity.
It’s difficult to ignore the fact that production capacity—the amount of calories a nation can produce domestically—is still frequently brought up when discussing the resilience of the food system. That misses the point, but it’s not unimportant. Production isn’t the primary source of fragility. It is found in the invisible biological layer that runs beneath the supply chain, such as the pathogens that outpace regulatory systems, the antimicrobial resistance that develops covertly in livestock operations, and the surveillance gaps that allow a contaminated shipment to pass from a farm in one hemisphere to a hospital in another before anyone notices it. Counting bushels is not enough to fix that.
