NEW DELHI - Indian states are sitting on more than 200 million doses of Covid-19 vaccines due to a reluctance among people to get inoculated, the chief executive of top vaccine maker the Serum Institute of India (SII) said on Wednesday (Nov 17).

"The vaccine industry has worked tirelessly to provide enough stocks for the nation," SII CEO Adar Poonawalla said on Twitter, as his family-owned company prepares to resume exports to the COVAX international vaccine sharing programme for the first time since April.

"Today there are over 200 million doses available with states. I urge all adults to get vaccinated as soon as possible. Vaccine hesitancy is now the greatest threat in overcoming this pandemic," he said.

A version of the AstraZeneca vaccine produced by SII accounts for nearly 90 per cent of the 1.24 billion doses administered in India.

Despite the ample supply, only 41 per cent of India's 944 million adults have been fully vaccinated as many skip their second dose amid a decrease in infections.

Some 80 per cent of the adults have received at least one dose, while vaccination has not begun for those under age 18.

The government this month launched a door-to-door vaccination campaign to cover all adults with at least the first dose by next month and ensure people also take their second shots.

India has reported about 34.5 million infections, the most after the United States, and more than 464,000 deaths.

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