Dengue and suspected Japanese encephalitis have claimed 45 lives and left more than 2000 people ill in West Bengal in the past few weeks, officials said on Wednesday.

Chief Minister Buddhadeb Bhattacharya declared a dengue epidemic last week, after admitting that the number of cases was 'way above normal'.

While dengue has killed nearly 20 people across the state, a suspected case of Japanese encephalitis claimed 25 lives in the central district of Malda in a fortnight. Malda's chief medical officer, Gopal Sarkar, said they were worried because in some of the victims, the fever had affected their brains.

• WB: 'Dengue outbreak not an epidemic'

Sarkar said they were struggling to control the outbreak of the fever, in absence of proper and adequate infrastructure in district hospitals. "We are trying to conduct entomological and epidemiological survey to find out the specific vector causing the disease," he said.

Officials from Indian Council for Medical Research visited hospitals and expressed dissatisfaction with the measures taken to fight dengue and other unknown diseases. Dengue, which is transmitted through mosquito bites, is marked by high fever, headache, rash and nausea, and if not treated on time, it can lead to death.

An uncontrolled encephalitis outbreak in northern India's Uttar Pradesh state has killed more than 700 people, mostly young children, in the past few weeks.

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