After one death and more than 500 individuals falling ill in southeastern India over the weekend, officials are now closer to solving the mystery behind the mysterious illness.

According to some reports, the outbreak started on Sunday after residents of Eluru began passing out and convulsing, and experiencing other symptoms like anxiety and nausea.

USA Today reported that a person even died due to the mysterious disease as the 45-year-old man was admitted to the hospital for displaying epilepsy-like symptoms.

Based on some reports, none of the 555 individuals treated for the mysterious illness tested positive for coronavirus, likely ruling out a possible correlation to the outbreak.

Also mentioned in the report, not less than 300 of the patients were children.

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Possible cause

Health officials appeared closer to finding the cause of the illness on Tuesday after they executed a preliminary analysis, which suggested that it was heavy metal poisoning.

According to Reuters, the researchers at India's All-India Institute of Medical Sciences conducted a preliminary analysis using blood samples of 10 patients, wherein they have found traces of nickel and lead particles.

Despite the tests conducted, the sample size is too small to confirm that heavy metal poisoning is the primary cause.

It is still unclear how Eluru citizens may have been exposed to heavy metals, which prompted the government to conduct an inquiry into the source of the heavy metals based on a report.

The health commissioner of the state shared that initial tests of the local water and supply came up negative for the chemicals discovered in the patients' blood. 

The Times of India reported on Wednesday that the result from a leading private laboratory had found high levels of pesticides in the drinking water.

According to the lab, the insecticide, dichlorodiphenyldichloroethane (DDD), was found at levels of 14.21 and 15.23 per mg/I, far above the acceptable limit of 0.0001.

Moreover, Alachlor, a herbicide, was also recorded at levels of 17.64, wherein the acceptable level was only 0.001, Times of India further reported.

An Indian politician, G.V.L. Narasimha Rao, tweeted on Sunday that he was able to talk with health experts who believed that the said chemicals normally found in pesticides were most likely the cause of the mass illness.

DDD is an organochlorine insecticide. Organochlorine substances are commonly used in insecticides and pesticides but have been restricted or banned in most countries due to their link to cancer.

But the usage of the chemical has not been regulated in India, despite links to deaths in the past.

Based on a report, if a person will be exposed to organochlorines, it can lead to headache, convulsions, vomiting, nausea, confusion, slurred speech, salivation, sweating, and tremors.

The Eluru residents have been blaming the massive illness on the organochlorine pesticides recently used in the latest anti-mosquito campaign in the area.

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