AstraZeneca is already used in more than 180 countries and Pfizer is used in more than 145 countries. Undoubtedly the two best studied vaccine types, the combination of the two is the first to undergo research on multivariate vaccines and booster vaccines – Readable On the portal.
Previous research has shown that two doses of AstraZeneca 70 percent and two-dose Pfizer provide 90 percent protection 6 months after vaccination – but we know that protection decreases over time, and it is now clear that a booster dose is needed. .
The COV-BOOST study looked at the third dose in terms of immunity and safety of booster doses, i.e. frequency and severity of side effects. The researchers examined Astrogenogen, A Pfizer, A Novavox, A Johnson, A Modern, A Valneva And this Guerrero Vaccines as a booster dose after two Astrogenogen or two Pfizer vaccines.
All seven vaccines are safe for side effects, usually local inflammatory reactions (injection site pain, muscle aches, fatigue). Each vaccine showed adequate immunity to the spike protein when given after AstraZeneca, but only six after Pfizer, and Valneva did not perform well at that time. It should be noted that the immune response is limited to the number of antibodies and T-cell immunity in research.
However, studies measuring the efficacy and safety of the booster dose 7-8 months after the first series of vaccines will be required, and in the current second phase study, participants received booster doses 10–12 weeks after the first two vaccines.
A total of 2,878 people participated in the research, over 30 years of age and half of the group over 70 years of age. After 28 days, the antibody response to booster vaccines was strong regardless of age.