Up to two-thirds of India's population may have been infected with Covid-19, a government study has suggested.

The blood serum survey of about 29,000 people in June and July showed 67.6 per cent of those tested had antibodies, AFP reported.

The results of the study by the Indian Council of Medical Research (ICMR) show the impact of a devastating surge of cases in April and May, when India reported about 400,000 cases and 4,000 deaths per day.

In December and January, less than 25pc of those in a similar study had positive antibody tests.