Can you mix and match Covid-19 vaccines?

Published June 17, 2021
Medical staffers from Taiwan’s vaccine maker Medigen Vaccine Biologics Crop (MVC) work at a lab in Hsinchu on June 17. — AFP
Medical staffers from Taiwan’s vaccine maker Medigen Vaccine Biologics Crop (MVC) work at a lab in Hsinchu on June 17. — AFP

Can you mix and match two-dose Covid-19 vaccines? It's likely safe and effective, but researchers are still gathering data to be sure.

The authorised Covid-19 shots around the world are all designed to stimulate your immune system to produce virus-fighting antibodies, though the way they do so varies, noted Dr Kate O' Brien, director of the World Health Organisation's vaccine unit.

"Based on the basic principles of how vaccines work, we do think that the mix-and-match regimens are going to work," she said.

Scientists at Oxford University in the United Kingdom are testing combinations of the two-dose Covid-19 vaccines made by AstraZeneca, Moderna, Novavax and Pfizer-BioNTech. Smaller trials are also ongoing in Spain and Germany.

"We really just need to get the evidence in each of these (vaccine) combinations," OBrien said.

Read more: All you need to know about Covid vaccines in Pakistan

So far, limited data suggests an AstraZeneca shot followed by the Pfizer shot is safe and effective. The combination also appears to come with a slightly higher likelihood of temporary side effects like aches and chills.

"That might be because mixing and matching different types of vaccines can often produce a stronger immune response," said Lawrence Young, a virologist at the University of Warwick in the United Kingdom.

In some places, health officials already suggest mixing in select circumstances.

After the AstraZeneca vaccine was linked to extremely rare blood clots, many European countries including Germany, France and Spain recommended people who got it as a first dose get a Pfizer or Moderna shot as a second dose instead.

In Britain and Canada, officials say people should aim to get the same vaccine for their second dose if possible. If they got AstraZeneca as their first shot, they're advised to get another vaccine only if they have a history of blood clots or other conditions that might put them at higher risk of clots.

Opinion

Editorial

Losing grip
Updated 29 Jan, 2023

Losing grip

The state and the government are responsible for providing Imran with the security he deserves as a former prime minister.
Telling silence
29 Jan, 2023

Telling silence

THE silence of the Sindh government over the recent exposé in this paper about Karachi’s water tanker mafia ...
Palestine escalation
29 Jan, 2023

Palestine escalation

THE fire of conflict once again threatens to envelop the land of Palestine, as the growing cycle of violence refuses...
IMF package
Updated 28 Jan, 2023

IMF package

While it is crucial to seek immediate IMF funding to shore up its reserves, the govt shouldn’t focus only on short-term relief.
Dar unpegged
28 Jan, 2023

Dar unpegged

IT is over. Nearly four months after Ishaq Dar descended on the cash-strapped economy with some decidedly outlandish...
Lurking hazards
28 Jan, 2023

Lurking hazards

OVERSIGHT of illegal industrial activity occurring within residential areas in the country is weak, especially in...