The World Health Organization's chief scientist advised against people mixing and matching COVID-19 vaccines from different manufacturers, calling it a "dangerous trend" since more data is needed about the health impact, Reuters reports.
"It's a little bit of a dangerous trend here," Soumya Swaminathan said at an online briefing. "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."
However, earlier, the European Medicines Agency said there are “good scientific grounds” to suggest that mixing COVID-19 vaccines is safe and effective. That’s because, currently, all the approved vaccines work in a similar way — by stimulating an immune response to the viral spike protein, the EMA said in an email.
In addition, early data from Spain and Germany suggests “a satisfactory immune response and no safety concerns,” the regulator said.