The World Health Organization’s chief scientist on Monday advised against people mixing and matching COVID-19 vaccines from different manufacturers, calling it a “dangerous trend” since there was little data available about the health impact
“It’s a little bit of a dangerous trend here. We are in a data-free, evidence-free zone as far as mix and match,It will be a chaotic situation in countries if citizens start deciding when and who will be taking a second, a third and a fourth dose.”Soumya Swaminathan told an online briefing.
Earlier this month, The New York Times published an article on Britain opening the door to mix-and-match vaccinations. Some COVID-19 vaccinations require two doses, given at different times. Both Pfizer/BioNTech’s and Moderna’s call for two doses.
According to updated U.K. guidelines, if the same vaccine is not available or if the first product received is unknown, it is reasonable to offer one dose of the locally available vaccine. But the guidelines also say every effort should be made to do two doses of the same vaccine. Mary Ramsay, head of immunizations at Public Health England, told Reuters mixing and matching was not recommended and would only happen on extremely rare occasions.
The World Health Organization announced last week that the wait between the first and second doses may be extended up to six weeks.