New York, Apr 1 (IANS): Errors at a manufacturing plant in the US has ruined 15 million potential doses of the Johnson & Johnson Covid-19 vaccine, The New York Times reported.

The quality issue was identified at a manufacturing plant in Baltimore run by Emergent Biosolutions, a site not yet authorised to manufacture drug substance for Johnson & Johnson's Covid-19 vaccine.

The error is delaying the authorisation of the plant's production lines as the US Food and Drug Administration (FDA) investigates what occurred.

Emergent Biosolutions is also a manufacturing partner for AstraZeneca, whose Covid-19 vaccine has not yet been approved in the US.

The problem at the plant has been reported to be an ingredient mix-up due to "human error".

No issues were reported for the Johnson & Johnson vaccine doses that are being delivered and used in the US currently though.

Those doses were manufactured in the Netherlands, where production lines have been fully approved by federal regulators, the Times reported on Wednesday.

Johnson & Johnson said in a statement that the "quality control process identified one batch of drug substance that did not meet quality standards at Emergent Biosolutions, a site not yet authorized to manufacture drug substance for our Covid-19 vaccine."

"This batch was never advanced to the filling and finishing stages of our manufacturing process," the company said.

According to a report in The Verge, about 30 per cent of the US population has received at least one dose of a Covid-19 vaccine so far.