An estimated 66 to 70 percent of India's 1.3 billion population have been infected with Covid-19, concluded a sero-survey conducted in July.

The remaining population is at high risk of infection, according to a top health ministry official.

Chairman of India's Covid-19 Working Group of the National Technical Advisory Group on Immunisation (NTAGI), NK Arora, said the remaining 30 percent can be infected any time and develop severe Covid-19, particularly if they are still unvaccinated, reports our New Delhi correspondent.

Arora said almost 30,000-45,000 daily cases on average are being reported in India for the last several weeks, mostly from Kerala, northeastern states, a few districts of Maharashtra, and some other southern states.

He also said no new variants were found in the genomic analysis of SARS-COV-2 viruses circulating in June, July, and August.

According to Arora, most of the Covid-19 vaccines are not adequately effective in preventing infection, and therefore, it is repeatedly emphasised that even after vaccination, a person can spread infection and hence the need to maintain health protocols.

"The most important value of the Covid-19 vaccines is their effectiveness to prevent severe disease, need for hospitalisation, and death," he said.