By Sardar Khan Niazi

El Niño is often described as a climate phenomenon: a periodic warming of the tropical Pacific that disrupts weather patterns across much of the world. But for millions of people, that description is too clinical and too distant. El Niño is also a public-health warning. The latest episode should remind governments that extreme weather is not merely an environmental problem to be dealt with by meteorological departments and disaster-management agencies. It is a health emergency waiting to happen. The World Health Organization’s latest assessment of El Niño 2026 highlights the familiar chain of risks: extreme heat, floods, drought, wildfires, food insecurity, infectious diseases and disruption to essential health services. The lesson is straightforward: by the time patients begin arriving at emergency departments, it is often already too late to call the response a preparedness strategy. El Niño does not produce the same weather everywhere. In some regions it can bring excessive rainfall and flooding; elsewhere, drought and heat become the greater threat. Those conditions can alter the spread of mosquito-borne and waterborne diseases, damage crops, threaten drinking-water supplies and worsen malnutrition. WHO notes that El Niño can also affect health infrastructure itself, precisely when communities need it most. The greatest weakness is therefore not a lack of scientific knowledge. El Niño can be anticipated months in advance. Seasonal climate information can give health authorities time to prepare for predictable risks. The real weakness is turning that information into action. A health ministry should not wait for a heatwave before asking whether hospitals have enough electricity, water, medicines and staff. Disease-control programs should not wait for an outbreak before strengthening surveillance in areas where changing rainfall and temperature may favor mosquitoes. Food authorities should not wait for harvest failures before assessing the nutritional consequences of drought. Nor should preparedness end at the hospital gate. Extreme weather exposes the inequalities that already exist in society. A family with reliable electricity, clean water, secure housing and access to healthcare can withstand a heatwave or flood differently from a family living in an informal settlement. An outdoor labourer cannot simply avoid dangerous temperatures by staying indoors. A child suffering from malnutrition has fewer reserves when food prices rise or clean water becomes scarce. This is why climate preparedness must increasingly become public-health preparedness. There are practical measures that governments can take. Heat-health action plans can identify vulnerable populations and establish early warnings. Disease surveillance can be linked more closely to meteorological information. Hospitals can assess whether their buildings, backup power, water supplies and cooling systems can continue operating during extreme weather. Emergency stocks can be positioned before roads are cut off by floods. Public information campaigns can tell communities not only that extreme weather is coming, but what they should do about it. Early warning, however, is valuable only when it is connected to early action. The World Meteorological Organization has repeatedly stressed the lifesaving potential of early-warning systems. Yet warnings that do not reach vulnerable communities, or reach them without the resources needed to act, are little more than information. There is another uncomfortable reality. El Niño is a natural climate phenomenon, but it now operates against the background of human-caused global warming. WMO has emphasized that while El Niño can contribute to record temperatures, the long-term warming caused by greenhouse gases is the dominant driver of the underlying trend. That distinction matters. Preparing for El Niño cannot substitute for addressing climate change, just as reducing emissions cannot substitute for preparing communities for the extreme weather already occurring. The public-health system must therefore learn to think differently about climate. A flood is not simply a disaster-management event; it can become a waterborne-disease emergency. A drought is not simply an agricultural crisis; it can become a nutrition and mental-health crisis. A heatwave is not merely uncomfortable weather; it can overwhelm hospitals and increase deaths, particularly among vulnerable people. The costs of preparation are real. But the costs of being unprepared are paid in lives, illness, lost livelihoods and overwhelmed health systems. El Niño will eventually weaken. Another climate pattern will follow it. The precise location and intensity of the next disaster may be uncertain, but the health consequences are not difficult to anticipate. The question, then, is not whether extreme weather will test public-health systems again. It is whether governments will use the warning before the next test arrives. El Niño gives us something rare in disaster preparedness: advance notice. We should use it.