Health risk: Smoke billows from a burning area of land in Pampangan, Ogan Komering Ilir, South Sumatra, on Saturday. The National Institute of Aeronautics and Space (Lapan) recently reported 197 hot spots in Indonesia.(Antara/Nova Wahyudi)As fires continue to raze forests and peatland in Sumatra and Kalimantan, a wake-up call has come from a group of researchers who estimate that haze produced on the islands potentially caused 100,000 deaths in the region in 2015.

The team of public health and atmospheric modelling scientists from Harvard and Columbia universities estimated that 2,200 premature deaths occurred in Singapore, 6,500 in Malaysia and 91,600 in Indonesia due to the haze last year.

The estimate is much greater than the official number given by the Indonesian government, which said only 19 people died from the haze in that period.

“Now fires are back agai...