Researchers from Spain who conducted a study on combining different coronavirus vaccines found out that inoculating people with AstraZeneca and Pfizer jabs is safe.
The Carlos III Health Institute (ISCIII) presented the preliminary results from the clinical trial of over 600 people in an online forum on May 18 showing the benefits of mixing different brands of COVID-19 jabs.
The Combivacs study found the presence of IgG antibodies in the bloodstream was 30 to 40 times higher in people who got the follow-up Pfizer shot than in a control group who only received AstraZeneca dose.
Moreover, the presence of neutralizing antibodies increased sevenfold after a Pfizer shot, significantly higher than the doubling effect observed after a second shot of AstraZeneca.
Around 670 participants in the study were administered with first dose of AstraZeneca shot with 450 of which given a Pfizer vaccine.
According to Dr Magdalena Campins, one of the lead researchers of the study, only 1.7 per cent of the participants experienced severe side effects, which were limited to headaches, muscle pain and general malaise.
“These are not symptoms that can be considered serious,” Dr. Campins stressed.
A similar study being conducted in the United Kingdom is expected to release further findings on its effectivity soon.
