Over the weekend, the city of Eluru in southern India was slammed with a mysterious illness that has hospitalized more than 550 people with symptoms including a loss of consciousness, convulsions, seizures, and an unexplained giddiness. The outbreak is unrelated to the current COVID-19 pandemic, as none of the patients had tested positive for the SARS-CoV-2 virus. While there are preliminary hypotheses about the cause of the illness, no definitive cause has been named yet.
Beginning on December 5, hundreds of people around the city began experiencing symptoms. There was no common thread between them, as the patients lived in various areas around town, had different water sources, were unrelated to one another, and represented a wide range of ages, according to multiple news sources.
The Associated Press reports that the state of Andhra Pradesh, where Eluru is located, has been hit hard by the COVID-19 pandemic, with more than 800,000 cases to date. However, none of the patients tested positive for that or any other viral disease, including mosquito-borne illnesses such as dengue fever and chikungunya, CNN adds.
According to the Hindustan Times, the All India Institute of Medical Sciences found traces of lead and nickel in blood samples from some of the patients. While heavy metals can have neurotoxic effects in the human body, there is not yet a clear source. Waterways, milk, food sources, and other avenues of possible contamination have been tested so far, but no evidence has been found.
“We have tentatively identified the primary cause of this strange phenomenon, but it is not yet clear what its source is and how and why it has happened. For instance, the chemicals were found in the bodies of the patients but not in either water or any other food substance,” health commissioner Katamaneni Bhaskar tells the Times.
The majority of the patients have been released from the hospital, and the 84 who remain are expected to be discharged soon, according to The Indian Express. A 45-year-old man is the only fatality among the patients, though he had a heart attack unrelated to his hospitalization.
Health officials from across the country continue to search for the culprit. Bhaskar tells the Times that he expects investigators will identify it within the next couple of days.