A new study on Monday found that antibody levels improved in people who got a shot of the Covid- 19 AstraZeneca coronavirus vaccine and then a trial of the Pfizer vaccine. If the results hold, they could lead countries to combine the AstraZeneca vaccine with another vaccine to improve results.
The most used vaccine is AstraZeneca in some countries, though the Pfizer and Moderna vaccines are much more widely used in the United States. The study was conducted by the Korea Disease Control and Prevention Agency in South Korea and involved 499 medical workers.Nearly 100 participants participated in the study and received one shot of each of the two vaccines. The other 200 took two doses of the Pfizer shot, and the remaining participants got two doses of the Covid- 19 AstraZeneca shot.
The delta variant of the Covid- 19 virus has fueled the rise of cases throughout the world, with unvaccinated people being the vast majority of those contracting the virus.None of the groups demonstrated reduced neutralizing activity against the Alpha variant, first identified in Britain, but the neutralization decreased by 2.5 to 6 fold against Beta, Gamma, and Delta, first detected in South Africa, Brazil, and India, respectively.