Malignant malaria claimed its first victim this season in a ward represented by the chairman of the Calcutta Municipal Corporation (CMC), sparking a blame game over the mosquito menace.

Raja Nath, a 16-year-old resident of Sarsuna in Behala, died at the Ramakrishna Mission Seva Pratishthan on Wednesday afternoon after a bout of “Falciparum malaria with shock (malignant malaria),” his death certificate said.

But CMC chairman Nirmal Mukherjee disputed the cause of death. “He died of cerebral haemorrhage that has no connection with malaria. If there is an outbreak of malaria in the area, we will definitely take steps.”

Mukherjee is the councillor of ward number 127, which includes Sarsuna.

Raja, a student of Class XI at Sarsuna High School, had high fever since September 10. “He started vomiting blood last Friday,” said uncle Swapan Debnath.

Blood tests confirmed the presence of Plasmodium falciparum, the parasite that causes malignant malaria. “He started bleeding from the nose and mouth on Wednesday and died within hours,” Debnath said.

Raja had passed Madhyamik this year with first-division marks. His father Utpal Kanti Nath owns a textile shop in Sarsuna.

Chief municipal health officer DebDwaipayan Dutta meanwhile insisted that malaria hadn’t taken a single life in the city this season. He said the incidence of malaria had actually decreased, contradicting the findings of a survey carried out last month. One of the findings, reported by Metro on Thursday, was that malignant malaria had afflicted five times more people in the city than last year.

Residents of Sarsuna blamed the CMC for the mosquito menace. “No repellent has been sprayed in our area over the past two years. The open drains are the breeding ground for mosquitoes,” said Kinkar Ghoshal, a neighbour of the Naths.

Behala is infamous for waterlogging. This year has been particularly bad for some parts of the sprawling locality. “We have been facing the mosquito menace for years, but the civic authorities have done nothing to solve the problem,” said Chandan Nath, another uncle of Raja.

Officials of the CMC's health wing said Delhi had officially asked the civic body to step up its anti-malaria campaign. According to CMC data, 390 cases of malaria and 38 of malignant malaria had been reported till August. A central government survey revealed that the incidence of both the benign and malignant forms of malaria was on the rise in Calcutta since 1970. Around 1,400 Calcuttans were afflicted by malaria in 1970, but the numbers rose to 68,000 by the turn of the century.

Critical care specialist Subrata Maitra said Chloroquin, the standard drug for malaria, might no longer be effective in treating Falciparum malaria because of drug resistance. “Once diagnosed with cerebral malaria, the patient should be treated with the Artisunate group of drugs. Quinine is an alternative. Delay in treatment could lead to multiple organ failure,” warned Maitra.