The death toll from a raging Encephalitis epidemic in northern India is nearing 400 with about a dozen people, mostly children, dying daily, a senior health official said on Thursday. “Around 10-15 people have been dying almost daily since the past three weeks. The toll should now be touching 400,” O.P. Singh, director-general of health services in the northern state of Uttar Pradesh, told Reuters.

He said 11 patients died in the past 24 hours in the worst-affected Gorakhpur district.

Around 1,100 people, mostly children aged 5 to 13 years, have been hit by the brain infection in the district since the outbreak was first reported there on July 27, he said.

Encephalitis proliferates in water-logged parts of India during the monsoon season. According to official estimates, about 1,500 people had died of encephalitis in Uttar Pradesh in the past 27 years.

The disease leads to an acute form of brain infection caused by a virus spread by mosquitoes.