Health officials say nine more people have now died from Japanese encephalitis in India's Uttar Pradesh state, taking the death toll from the mosquito-borne disease to 99.
Of the deaths from the water-born disease, 79 are apparently children, but more than 300 people have been hospitalized, many of them in a critical condition, and it is highly likely some cases have not been reported.
Officials in the northern state say there is an acute shortage of a preventive vaccine. Uttar Pradesh needs 50m vaccines every year, but the Kasauli-based Central Institute is apparently only able to supply 200,000.
At least 182 children are reported to have been admitted to various government hospitals, and more than a hundred of those are in serious condition.
It seems children between the age of six months to 15 years are worst-affected.
K.P. Kushwaha, a health official in Gorakhpur, a large town in eastern Uttar Pradesh, says they expect the death toll to rise as more patients are being brought in to hospitals.
Kushwaha says as many as two dozen patients were being admitted into the main government hospital in Gorakhpur every day with the symptoms of encephalitis which include fever, muscle ache and vomiting.
The virus is spread by mosquitoes and proliferates in water-logged parts of India during the monsoon season, and causes an acute form of brain fever and often hits children.
The virus kills dozens of people each year in Uttar Pradesh, India's largest state; official estimates, over the last 25 years, it has killed about 3,500 people there.
Last year 50 people are reported to have died of the disease in the northern state.
During this year's monsoon season, which runs from June to September, India experienced heavy rains and serious flooding.