Encephalitis has already killed at least 118 children this year, and authorities fear the death toll could reach about 1,000, said Dr. R.N. Singh of the Encephalitis Eradication Movement, an Indian non-profit.
While India's efforts against polio and tuberculosis get plenty of attention, the poor farmers and day labourers of eastern Uttar Pradesh state face an almost-silent emergency, battling a disease that has killed thousands of children over the past eight years.
Many families have taken out crushing loans for treatment. The children who survive often cannot communicate because of brain damage. They stare off listlessly, unable to recognize friends they played with just months before. Some are so severely disabled that their impoverished parents are told to abandon them.
Sangita Devi's 4-year-old son Anup Kumar has been in a hospital for four months.
"We have mortgaged our house for our son's treatment. But there is no improvement in his condition. He cannot even stand now," she said.
The disease is predictable and preventable. Every year the monsoon fills the region's parched paddy fields, heralding the arrival of the mosquitoes that spread Japanese encephalitis from pigs to humans, devastating malnourished children with low immunity. Another strain of the disease — Acute Encephalitis Syndrome — spreads through contaminated water. Residents use the fields for defecation, contaminating the ground water.
A vaccine has long been available, but the state government — which spent tens of millions of dollars building monuments to its last top politician — has failed to muster the sustained political will to focus on the communities hardest hit by the illness.
The disease killed more than 1,500 children in 2005, the worst recent year,
Shocked by the deaths, Uttar Pradesh's highest court in 2006 asked the state and federal governments to declare encephalitis a national health emergency. "A concrete action plan must be drawn," it said.
That year the government started vaccinating children against Japanese encephalitis. The government vowed to immunize every child in the worst-affected areas and to launch a massive drive to improve sanitation. For a couple of years, the numbers dropped. In 2006, the disease killed 431 children.
But the crowded hospital wards of the tiny town of Gorakhpur reflect how the immunization drive has fizzled out. Last year, more than 700 children died.
Amid the cloying smells of ether and disinfectant, 7-year-old Amit jostled his mother. His words were slurred and, every time he tried to break free of her grip, he fell to the floor. She kissed his dry and dirty cheek.
"He cannot stand on his own any more. He cannot speak. Cannot say whether he wants food or water. He has no control over his bladder," said his mother, Kunti, as she held him close. Like many poor Indians they use one name.
Her husband, a labourer on a construction site in neighbouring Bihar state, earns about 180 rupees, or $3, a day. He had to borrow $850 from a money lender to pay for his son's treatment, and had to sell his only cow.
The family is like hundreds of others in this area. They have sold their tiny fields, their cattle and their bits of family jewelry. They have buried themselves under loans they may never be able to repay. They have done all this to give their children some hope of a normal life.
Health experts say the government has made repeated mistakes in the fight against encephalitis. Most of the 7.5 million children vaccinated between 2006 and 2010 were given only a single dose of a two-dose vaccine, said Singh, of the Encephalitis Eradication Movement.
"Who is responsible for the children who died between 2006 and 2010?" Singh asked.
In 2010 the vaccination drive suddenly stopped because funds dried up. The sanitation drive never fully started.
To make matters worse, in the 23 worst-affected districts in the state, only one hospital — the Baba Raghav Das Medical College in Gorakhpur — is equipped to deal with the hundreds of sick children. They fill its 108-bed encephalitis ward.
"By the time they reach here, it's too late," said Dr. K.P. Kushwaha, who heads the hospital.
According to hospital data, 5,136 children with encephalitis died in its wards between 2005 and 2012. This year, 118 children had died by the end of May. The figures don't include children treated at private clinics or those who never made it to medical care.
Survivors who develop brain damage, common among young children, have no rehabilitation centres despite a 2011 court order telling the state government to set them up.
For Amit's father, Birza Majhi, there is little hope.
"People in my village have asked us to leave our son at a railway station or somewhere else. They say this boy has no future. He is just a burden on us," he said. "How can we do it, sir? As long as I'm alive I'll keep trying."