20. MOH has done a study recently on the relative effectiveness of Pfizer-BioNTech and Moderna as booster shots in terms of reducing infection risks. We compared two combinations, one combination is P-P-P (three Pfizer-BioNTech shots) versus P-P-M (two Pfizer-BioNTech shots and Moderna as the third dose).
21. There are results for other combinations, such as M-M-M, and M-M-P, but I should caution that the sample sizes for these are not very large, and the statistics may not be as meaningful.
22. But just comparing P-P-P and P-P-M, the results are as follows. Relative to two Pfizer-BioNTech doses, P-P-P further reduces risk of infection by 62 percent. As for P-P-M, the reduction is 72 percent. So both mRNA vaccines work very well as boosters, with P-P-M having a slight edge. Regardless, the impact on the reduction of severity of illness is extremely high for both combinations.