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Research has been conducted around the world to try different types of corona vaccines for two doses. This is to check the safety of different vaccines to see if they are okay for the body and to solve the problem of lack of vaccines at the same time.
Reporter Nam Joo-hyun delivers the results of recent research in the UK and Spain.
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Interim results of a cross-vaccination clinical trial in the UK published in the world-renowned medical journal Lancet.
We looked for fever after vaccination, and 10% of those who were twice hit with AstraZeneca and 21% of those who were twice hit with Pfizer had a fever.
However, when cross-vaccinating, the rate of adverse reactions increased significantly.
After AstraZeneca, 34% of those who received the Pfizer vaccine, on the contrary, 41% of those who received Pfizer-AstraZeneca had a fever.
The Spanish state research institute focused on neutralizing antibodies that neutralize the virus.
Of the 670 people who received the first AstraZeneca vaccine, 450 were given a second dose of the Pfizer vaccine.
Neutralizing antibodies generated after the first vaccination increased 7 times after the second Pfizer vaccination.
Normally, when the vaccination is completed with AstraZeneca alone, the increase is only 3 times.
The researchers found that "the number of side effects was only 1.7%."
In terms of safety, different results have been obtained, and research on the immune effect is still lacking.
Germany and France have allowed first-line AstraZeneca vaccines to be given after controversy over rare blood clots.
However, our health authorities are cautious about cross immunization.
[Kim Ki-Nam/Corona 19 Vaccination Management Team Leader: In the case of severe side effects, AstraZeneca vaccination is excluded from the 2nd vaccination, but no one is targeted so far... .]
However, the health authorities said that our National Institute of Health is also conducting a study on cross vaccination.
(Video coverage: Kang Dong-cheol, Video editing: Lee Hong-myeong)