Mayor Sovan Chatterjee has made the departmental heads, borough chairpersons and councillors of the Calcutta Municipal Corporation directly accountable for vector control, leading some public health experts to question whether the November wake-up call couldn’t have come before dengue started killing.

In an identical letter to the heads of various departments and the chairpersons of all 16 boroughs, the mayor has said that inter-sectoral meetings focused on vector control must be held in their areas of jurisdiction twice every month and involve the respective councillors.

According to a civic official, the communication hadn’t come a day too soon. “Getting the councillors to accept responsibility for vector control has always been difficult. Now that the mayor has sent an official note, the councillors will be forced to attend meetings and assist us,” he said.

The anopheles and Aedes aegypti vectors — the first one causes malaria and the other dengue — breed in fresh water and multiply the fastest wherever pockets of water are created. In Bengal, a period of four to five months starting at the fag end of the monsoon is typically the season when mosquitoes breed rapidly.

“Any strategy to break this chain must start well before the period when you have bursts of rain followed by dry intervals with high temperature. By December, temperatures go down and lack of rain doesn’t leave many breeding spots for mosquitoes,” an entomologist said.

Several dengue deaths have been reported in Calcutta and its surrounding areas since the festive season started. “The letter has come too early for next year,” said a CMC official. “By the time all the borough chairpersons receive the letter and convene their first meetings, it will be mid-December.”

Metro was unable to contact the mayor for comment on Sunday evening.

An official of the CMC’s health department said several elected representatives had been “idle” for long. “Since the mayor has written that elected representatives must be involved in the meetings, I think we might finally see them show some interest in work.”

Borough-level staff of the health department said a councillor or the borough chairperson getting involved and listening to their problems would make a big difference. “Vector-control teams are not allowed inside many houses. If a councillor accompanies a team, it is likely that house owners will let our workers in,” an official said. “There are many vacant plots where people dump garbage that can potentially turn into mosquito-breeding sites. A councillor’s intervention could dissuade residents from doing that.”

Previous initiatives to involve councillors in vector-control initiatives made little difference for various reasons, officials said.

Atin Ghosh, the mayoral council member for health, had urged councillors to join the vector-control drive back in March. All wards were allocated Rs 20,000 to hire autorickshaws and microphones to spread awareness about malaria and dengue. But barring a few rallies at the start of the initiative, few councillors displayed any drive.