The World Health Organization (WHO) and US Centers for Disease Control and Prevention (US CDC) officials decisively state, “COVID-19 vaccines are not interchangeable.”
LONDON — The United Kingdom releases study results suggesting that mixing different Covid-19 vaccines may elicit a better immune response than two doses of the same vaccine. A WHO advisory panel in June stated that if there is a case where a second dose of the AstraZeneca vaccine is not available, receiving the Pfizer vaccine as a second jab might be done.
This advice actually serves as a solution for when vaccines are short in supply. This fix of mixing vaccines “may reduce the pressure on vaccine supply,” says GAVI, an international alliance that makes vaccines accessible to children all over the globe.
Multiple countries like Canada, Germany, Italy, Spain and Sweden have already embraced this practice.
“People who’ve received the first dose of AstraZeneca are permitted and, indeed, encouraged to receive a second dose of an mRNA vaccine,” says William Schaffner, MD, professor of infectious diseases at Vanderbilt University Medical Center.
However, Dr Soumya Swaminathan, the WHO’s chief scientist, calls this “a little bit of a dangerous trend.
“We’re in a data-free, evidence-free zone here as far as mix-and-match. There is limited data on 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,” says Dr Swaminathan.
CDC notes there are “exceptional situations” in mixing and matching vaccines, and this is when someone is not sure as to what vaccine they have received as their first dose. In this case, “any available mRNA Covid-19 vaccine may be administered” to accomplish the jabs. (HMP/The MiNT)