In early December 2020, an acute neurological disease broke out in Eluru, a city located in the southern Indian state of Andhra Pradesh.

The cause was initially unknown, but on 20 December, AIIMS and NEERI Research Institute came to a conclusion that pesticides leaching into the water supply is the most likely reason.

However, the district's health commissioner announced they had died from unrelated conditions - one from a stroke and one from COVID-19 - and that only the original death remained on the official count.

[19][28] On 7 December 2020, Indian health authorities unofficially declared: "Mostly yes, but we are waiting for the laboratory report [for confirmation]" when asked about organochlorine being the disease-triggering agent.

[5] State authorities later ruled out air and water as the medium for heavy metals and started testing vegetable and fruit samples.

AIIMS also reported on high heavy metal content in milk, while NEERI found mercury in surface water higher than the allowed concentration.

[33] Mahesh Kumar Mummadi et al. concluded that Triazofos (Organophosphate) pesticide contamination of water as a probable cause of the outbreak.

[10] Y. S. Jaganmohan Reddy, the former chief minister of Andhra Pradesh, has faced criticism from the opposition for his perceived failure to prevent the outbreak by neglecting water sanitation in the area.

[34] Chandrababu Naidu, the leader of the state's opposition Telugu Desam Party, blamed the ruling government for the outbreak, claiming that it had not taken action to decontaminate the local drinking water.

[38] The state government later formed a 21-member council which included representatives from the All India Institutes of Medical Sciences and the World Health Organization to investigate the outbreak.