Calcutta, Nov. 8: The health minister today said a late winter could increase the chances of vector-borne diseases spreading in the city that recorded its 12th malaria death in two months this afternoon.

Rajesh Mallick, a CMC casual worker who stayed in quarters allotted to civic staff in Chetla, died in Calcutta National Medical College and Hospital.

“He had fever for the past two days. We first took him to Bangur Hospital where blood tests confirmed malignant malaria,” said Rajesh’s friend Dhananjoy Singh.

The 28-year-old was taken to Calcutta National Medical College and Hospital after his condition deteriorated last night.

The toll from vector-borne diseases has now reached 26 in the city, including three in ward number 81, where Rajesh stayed.

Health minister Surjya Kanta Mishra said the situation could deteriorate.

“We cannot afford to be complacent. Winter is late this year. If it rains in between and there is fresh accumulation of water, the situation will become worse,” he said.

“Everyone involved in vector control needs to work harder.”

Mishra laid stress on early diagnosis, vector control and personal hygiene if the spread of mosquito-borne diseases had to be checked.

“All the three points are equally important,” the minister added.

He said the health department was conducting a case-by-case audit where there were confusions over the cause of death.

“We are studying each case where there is doubt about the exact cause of death,” the minister said.

He said malaria had already killed more people in the state this year than last year.

While 76 people died in 2007, the toll is already 81 this year.