One person has died and more than 400 have been hospitalised in southern India due to an unidentified infection that caused many to fall unconscious following seizures and nausea, a senior health department official said on Monday.
Government and medical authorities in the southern state of Andhra Pradesh said that more than 200 people were discharged at the weekend and that tests had ruled out COVID-19, the infection caused by the novel coronavirus. Further serological tests are underway.
“The causes of the outbreak are not known yet,” the state government said in a statement, adding that people in all age groups appeared prone to the infection.
Separately, the Union Health Ministry said on Monday it would send a team of three medical experts to investigate the outbreak, which has infected more than 300 children, it said.
“The children reportedly suffered from dizziness, fainting spells, headache and vomiting,” the ministry said, adding that a door-to-door survey was also underway.
The state health department were alerted to the first case over the weekend following the death of a 45-year old man, said Geeta Prasadini, a public health director in Andhra Pradesh.
“We have taken the patients’ blood samples for serological investigation and bacterial investigation to rule out any type of meningitis,” Prasadini told Reuters.
Authorities were investigating water supplies at 20 locations within the city of Eluru where the outbreak was first reported as well as neighbouring areas, she added.
Meanwhile, authorities are also investigating if organochlorines used as pesticides or in mosquito control caused the illness, a health official said on Tuesday.
Federal lawmaker GVL Narasimha Rao, who is from the state, said on Twitter that he had spoken with government medical experts and that the “most likely cause is poisonous organochlorine substances”.
“It is one of the possibilities,” said Prasadini. She said no new serious cases have come to light in the past 24 hours.
Organochlorines are banned or restricted in many countries after research linked them to cancer and other potential health risks. However, some of the pollutants remain in the environment for years and build up in animal and human body fat.
It was not immediately clear how extensively the chemicals are used in India, though it is found in DDT applied for mosquito control.
Exposure to organochlorine pesticides over a short period may produce convulsions, headache, dizziness, nausea, vomiting, tremors, confusion, muscle weakness, slurred speech, salivation and sweating, U.S. health authorities say.