Thus, around 15 million vaccines from Johnson & Johnson were destroyed, the newspaper writes.
The Emergent BioSolutions factory is a partner for both Johnson & Johnson and AstraZeneca and therefore makes vaccines for both companies.
The human failure means that production has been put on hold until the US Food and Drug Administration FDA has investigated the matter.
Johnson & Johnson vaccines that have already been used or distributed in the United States are manufactured in the Netherlands and thus not affected.
Deliveries of tens of millions of vaccines delayed
But all future deliveries from the company, estimated at tens of millions during April, were planned to be made at this plant in Baltimore.
Federal authorities believe there will still be enough vaccines available so that President Joe Biden can fulfill his promise to offer enough vaccines to all adults in the country before the end of May.
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