Can I get AstraZeneca now and Pfizer later? Why mixing and matching Covid vaccines could help solve many rollout problems

Many countries are considering “mix and match” Covid-19 vaccines in light of changing eligibility for the AstraZeneca vaccine, new coronavirus variants, and supply constraints.

In the face of changing eligibility for the AstraZeneca vaccine, new variants of the coronavirus and supply constraints, many people are wondering whether they can “mix and match” Covid-19 vaccines. This means, for example, having the AstraZeneca vaccine as the first dose, followed by a different vaccine such as Pfizer as the second dose, and boosters with other vaccines later on. While many studies are ongoing, data has recently been released from mix and match trials in Spain and the United Kingdom.