India has reported more than 8,800 cases of deadly “black fungus” in a growing epidemic of the disease.
The normally rare infection, called mucormycosis, has a mortality rate of 50%, with some only saved by removing an eye.
But in recent months, India saw thousands of cases affecting recovered and recovering Covid-19 patients.
Doctors say there is a link with the steroids used to treat Covid. Diabetics are at particular risk.
Doctors have told the BBC it seems to strike 12 to 18 days after recovery from Covid.
The western states of Gujarat and Maharashtra have reported more than half of the reported cases. At least 15 more states have reported between eight and 900 cases. Following the rise in cases, India’s 29 states have been told to declare the disease an epidemic.
Newly opened wards to treat patients suffering from the disease around the country are filling up fast, doctors say.