The 66-year-old German Chancellor Angela Merkel received her first dose of AstraZeneca Wuhan pneumonia (novel coronavirus disease, COVID-19) vaccine on April 16 and recently received her second dose of Moderna vaccine, a move that has sparked debate. German studies have shown that the administration of two different brands of vaccine results in a “particularly pronounced immune response” in the body, with the number of antibodies in the body being 10 times higher than that of two doses of the same brand.
The Deutsche Welle reports that because the initial clinical data on the AZ vaccine was incomplete, and cases of cerebral thrombosis occurred one after another, the German health authorities have been adjusting their vaccine policy, and many people who have received their first dose of AZ vaccine have chosen to switch to the Pfizer/BNT (Pfizer-BioNTech) or Moderna (Moderna) messenger ribonucleic acid (mRNA) vaccine for their second dose. The two mRNA vaccines are Pfizer/BNT (Pfizer-BioNTech) and Moderna.
In a preliminary evaluation at the Charité Hospital in Berlin, Germany, there were no significant adverse effects in terms of efficacy and tolerability if the first dose of AZ vaccine was administered and the second dose of Pfizer/BNT vaccine was administered. Leif Erik Sander, a researcher at Charité Hospital, said the study from Saarland showed even “a particularly pronounced immune response” to the two different vaccines.
Martina Sester, professor of immunology at the University of Saarland in Germany, said that the other group of people who received a combination of vaccines had 10 times more antibodies detected in their blood than those who received both AZ vaccines; in addition, tests for neutralizing antibodies showed that the combination was even better than two doses of the Pfizer/BNT vaccine. However, the study has not been reviewed by other scientists and the results have not yet been fully published.
A recent study published in the leading medical journal “Prickly Tick” (The Lancet) also showed that mild and moderate side effects were more intense in people who mixed vaccinations after the 2nd vaccination, but the Charité Hospital researchers believe that this may be related to interval differences, with no serious side effect problems occurring when two doses are given at longer intervals.