France is to announce that individuals under the age of 55 who have received their first dose of AstraZeneca's SARS-CoV-2 vaccine should receive one of the mRNA-based vaccines for their second dose, Reuters reports.
AstraZeneca has run into issues of transparency in its analyses and with reports of side effects with its vaccine. A number of countries, mostly in Europe, paused their rollout of AstraZeneca's vaccine following reports of a rare blood clot side effect. The European Medicines Agency announced, though, that the vaccine is safe and effective and that its benefits outweigh any potential risks, which led some countries to resume administering it.
Some countries like France, though, have advised that the vaccine only be administered to people over the age of 55, Reuters says, noting that the blood clot side effect has mostly occurred in young people. It adds that France is now following in Germany's footsteps to advise that people under 55 who have received one dose of AstraZeneca's SARS-CoV-2 vaccine should receive a different, mRNA-based vaccine for their second dose.
This decision, Reuters notes, is "significant" as mixing and matching of vaccines has not been tested in late-stage clinical trials.