OMM Newsroom
El Nino is strengthening rapidly and could trigger health impacts worldwide, with the most severe consequences expected in countries already dealing with fragile health systems and humanitarian crises, UN agencies warned on Tuesday.
“We’ve just lived through the two hottest months on record. Sea surface temperatures are at record levels,” Armel Castellan, an extreme heat adviser at the joint WHO-WMO climate and health programme, told reporters in Geneva.
According to the UN agencies, El Nino is expected to peak toward the end of 2026, although its effects are likely to continue beyond that point.
Southern Hemisphere faces heightened climate risks
As the event reaches its peak, much of the Southern Hemisphere — including southern Africa, South America and Australia — will enter its hottest season in early 2027. This could increase the risks of drought, wildfires, smoke and air pollution, Castellan said.
Teresa Zakaria, head of the World Health Organization’s unit for risk reduction, humanitarian operations and climate change, described El Nino as “a significant public health threat, not just a climate phenomenon.”
Food insecurity and disease risks
Malnutrition and cholera are assessed as “very high” risks in areas affected by drought and flooding, Zakaria said.
More than 150 million people are already experiencing acute food insecurity worldwide. That number is expected to rise as climate-related shocks disrupt food production and livelihoods.
Warmer temperatures and shifting rainfall patterns could also increase the transmission of mosquito-borne diseases, including malaria, dengue, chikungunya, yellow fever and Zika. These diseases could spread to areas where they have not traditionally been found.
“We have a window of opportunity to act now before these risks become crises,” Zakaria said.
