Rising temperatures and fluctuating monsoon rainfall could increase dengue-related deaths 13 per cent in India by 2030, and 23–40 per cent by 2050, according to a study led by Sophia Yacob and Roxy Mathew Koll from Indian Institute of Tropical Meteorology (IITM), Pune.
Published in Scientific Reports, the research explores how temperature, rainfall, and humidity influence dengue in Pune, a dengue hotspot. A combination of warm temperatures above 27°C, moderate and evenly distributed rainfall, and humidity levels of 60-78 per cent during June–September increases dengue incidences and deaths.
AI/ML prediction model
The research team developed an AI/ML model for dengue predictions, offering more than two months of lead time for outbreak preparedness. This gives adequate time for local administration/health department to enhance preparedness and response strategies.
The dengue early warning system incorporates all potential climate-based dengue factors (predictors) and their combined interactions at a regional scale. It used observed temperature, rainfall, and humidity patterns to predict potential dengue outbreaks by more than two months in advance, with reasonable skill.
Rainfall pattern matters
Rather than cumulative amounts, rainfall pattern was seen to play a crucial role in influencing dengue transmission in Pune. The India Meteorological Department (IMD) provides extended-range forecasts with information on active-break cycles of monsoon, 10-30 days in advance. These offer additional lead time for dengue predictions, the research said.
Dengue cases underreported
Heavy rains above 150 mm in a week could help reduce the dengue prevalence by flushing out the mosquito eggs and larvae, but the model shows overall increase in warmer days is dominating future changes in dengue.
Dengue is significantly underreported in India, IITM researchers quoting a study. Actual number of cases may be up to 282 times higher than reported figures. Effective early warning systems rely heavily on comprehensive health data collection and sharing. State public health departments play a crucial role in compiling and disseminating health data.
Cooperation lacking
“Cooperation from health departments is key to saving lives,” Koll said. States like Kerala, Maharashtra, West Bengal, Karnataka, Tamil Nadu, Gujarat, Punjab, Haryana, Andhra Pradesh, Telangana, Rajasthan and Uttar Pradesh bear a significant dengue burden. They can benefit from an advanced early warning system to enhance preparedness.
“We conducted this study and prepared an early warning system using health data shared by Pune’s health department. We approached Kerala and other states where dengue cases are high, but their health departments did not cooperate,” Koll said.