Under what circumstances should a COVID-19 vaccine be recalled?
Vaccine recalls or withdrawals due to safety issues are rare. Recalls are usually initiated voluntarily by a vaccine manufacturer before any adverse events are reported. For example, ongoing monitoring of vaccine production may show that an irregularity has caused a batch of vaccines to lose their strength. In this case, people who have received a vaccine from that batch may need to be vaccinated again to ensure they are protected.
Under what circumstances should a COVID-19 vaccine be recalled?https://www.who.int/news-room/q-a-detail/coronavirus-disease-(covid-19)-vaccines-safety#