Mystery illness puts 450 in hospital in Indian state of Andhra Pradesh
theguardian.com
theguardian.com
On the role of organochlorine in being the disease-triggering agent, an official told PTI, “Mostly yes, but we are waiting for the laboratory report (for confirmation).
https://news.ycombinator.com/item?id=25343122
Good guess though... -_-
I'm going to guess some kind of synthetic chemical leak.