South Africa has put its rollout of AstraZeneca's COVID-19 vaccine, originally due to start next week, on hold after a study found it offered only minimal protection against a new variant of the coronavirus currently dominating new infections in the country. The study found that the vaccine "does not work against mild and moderate illness" with the variant, the lead author said at a briefing, per the BBC. The vaccine was developed with Oxford, and Oxford's lead vaccine developer says it should still work to protect against severe illness. But the study could not determine that because the average age of participants was too young.
The country's health minister says the government will await advice on how to best proceed before using the 1 million vaccine doses it has received; until a decision is made, the Pfizer and Johnson & Johnson vaccines will be given. The new strain, known as 501.V2 or B.1.351, accounts for 90% of new COVID cases in South Africa. Experts say vaccines should be able to be modified in order to remain effective against new variants of the virus, but a modified version of the AstraZeneca vaccine was not expected until later this year. The study that led to the rollout's pause has been submitted for peer review, CNN reports. (Read more coronavirus vaccine stories.)