MANILA — El Niño's impact goes beyond water shortages and agricultural losses.
The World Health Organization (WHO) warned that the weather phenomenon can trigger a chain reaction of health risks, from extreme heat and infectious diseases to malnutrition and worsening chronic illnesses.
In its Global Public Health Situation Analysis: El Niño 2026, the WHO placed the Philippines among countries facing high to very high risks from several El Niño-related health threats. These include heat stress, infectious diseases, cardiovascular and other noncommunicable diseases, malnutrition, and mental health conditions.
WHO describes El Niño as a risk multiplier, changing temperature and rainfall patterns and creating environmental conditions that can affect how diseases spread and how people access food, water and healthcare.
HEAT, DENGUE AMONG MAJOR CONCERNS
Extreme heat is one of the biggest concerns. The WHO considers heat stress an almost-certain threat with very high overall risk under warmer and drier conditions.
Heat can cause heat exhaustion and heatstroke, while also aggravating cardiovascular, respiratory and kidney diseases among others. Pregnant women, children, older adults and people with chronic illnesses are also particularly vulnerable.
A separate projection from the Climate Impact Lab associated with the University of Chicago estimates that El Niño could lead to about 6,500 additional heat-related deaths in the Philippines from September 2026 to February 2027.
Across the Philippines, Vietnam, Thailand and Cambodia, the Climate Impact Lab projects around 19,400 additional heat-related deaths during the period.
Dengue is another concern.
WHO said drought does not necessarily mean a lower risk of vector-borne diseases. Water shortages can force households to store water, creating potential mosquito breeding sites while higher temperatures can also affect mosquito and virus behavior.
The agency identified dengue, chikungunya, and Zika, among the arboviral diseases that could pose increased risks under favorable conditions.
FOOD, WATER AND HEALTH SERVICES ALSO AT RISK
El Niño can also affect health indirectly. Droughts can reduce agricultural production, increase food insecurity and contribute to malnutrition, particularly among children and pregnant and breastfeeding women.
At the same time, water shortages can compromise hygiene and sanitation. In other areas where El Niño brings heavy rain or flooding, contaminated water and damaged sanitation systems can increase the risk of waterborne diseases.
The world body considers malnutrition and waterborne diseases such as cholera, among the significant health risks associated with El Niño. The health system itself could also come under pressure.
Climate-related hazards can disrupt health facilities, medical supply chains, disease surveillance and access to essential services—potentially creating a situation where more people need healthcare while delivering healthcare becomes more difficult.
WHO said the impacts of El Niño vary from one location to another, meaning health authorities need to use local weather forecasts and disease surveillance to anticipate risks.
For the Philippines, the agency recommended strengthening early-warning and disease surveillance systems, preparing health workers, protecting essential health services and identifying vulnerable communities before health impacts peak.
State weather bureau PAGASA has earlier said that the sheer strength of the El Niño is being seen as unprecedented. It therefore is not simply a problem of less water and hotter days. More than this, its effects can affect various aspects of everyday life like the environment, food and water, security, disease transmission and ultimately the health of millions of individuals.