How climate change could reshape Kerala’s dengue threat

A recent study led by researchers at the Indian Institute of Tropical Meteorology (IITM) in Pune suggests that climate change may be exacerbating Kerala's dengue threat. The researchers found that Kerala's warm, humid climate inherently supports the transmission of dengue, and El Niño weather patterns can further intensify these conditions, particularly before the monsoon season, increasing the risk of dengue during June and July.

The primary climate indicators linked to dengue incidents in Kerala include temperature, humidity, El Niño-Southern Oscillation (ENSO) conditions, rainfall, and the monsoon's active and break phases. The study, published in GeoHealth, highlights the complex interplay of these weather factors that contribute to dengue cases in the state.

Researchers at IITM used machine learning to develop a predictive dengue model that combines real-time climate forecasts and health surveillance, allowing for the prediction of up to 72% of dengue case variation. The pre-monsoon season in Kerala, characterized by high temperatures, humidity, and thunderstorms, marks the beginning of rising dengue cases, which peak in June and July.

Nearly 60% of all dengue cases reported in Kerala occur during the Southwest Monsoon season (June to September). During El Niño years like 2026, Kerala faces an additional challenge, as warmer pre-monsoon conditions due to El Niño create favorable conditions for greater dengue risk during the monsoon season. The IITM team has previously studied dengue incidents in Pune, Maharashtra, and plans to extend their research on vector-borne disease-climate variations to Chennai and Bhopal.