BANGALORE, INDIA (AFP) - Traces of heavy metals such as lead and nickel have been found in samples taken from 550 people stricken by a mystery illness in a southern Indian town where some victims have collapsed in the street, officials said.
The government has rushed medical experts to Eluru in Andhra Pradesh state to investigate the illness, which first appeared on Saturday.
One man died after showing the symptoms of seizures, nausea and chronic pain.
India is already in grip of the coronavirus with the world's second-highest number of cases, soon expected to pass 10 million. The illness has added to nerves in the region.
Hospital officials said 555 people had been treated since Saturday, including about 80 on Tuesday (Dec 8). One hospital has set aside 100 beds for victims but most have been sent home again.
Samples taken from 10 people showed high levels of lead and nickel in their blood, Eluru Government Hospital chief AV Mohan said.
State authorities have ordered an inquiry into the source of the metals and how they were spread.
Mohan added though that the sample was too small to be sure that the lead and nickel had caused the illness sweeping through the town of 200,000 people.
There are no major chemical factories in the region and wider tests on the water supply and even the milk drunk in the town have been carried out.
Experts from national medical institutes were also collecting samples of edible oil, rice and urine for analysis.
District officials have already pinpointed a possible role of chemical additives in pesticides.
"Some people are saying that it is mass hysteria but it is not," said AS Ram, a senior doctor at the government hospital.
"Most of the patients are coming in with minor head injuries or a black eye as they collapsed suddenly with the seizure," Ram said.
"But within one or two hours most of them are fine."
Police constable Kiran Kumar,who collapsed while on duty on Monday, said he had been left "scared" after being semi-conscious for more than two hours.
"My colleagues told me, I shouted something and collapsed. I injured my right shoulder due to falling on the road."