Thread by @sunlorrie

World Health Organization re expiry dates on AstraZeneca:
'Any vaccine that has passed its expiry date, including Covishield, should not be administered.'

'While discarding vaccines is deeply regrettable in the context of any immunization programme, WHO recommends that these expired doses should be removed from the distribution chain and safely disposed.'

'The shelf-life of a vaccine is a reflection of how long the vaccine retains its potency and stability at a given storage temperature and therefore its effectiveness. The shelf-life is used to establish the expiry date of each batch of the vaccine product.'

'Expiry dates do not affect the safety of the vaccine, rather are related to the potency or amount of protection the vaccine gives.'

Source: Expiry date and shelf life of the AstraZeneca Covishield vaccine produced by the Serum Institute of India: afro.who.int/news/expiry-da…