New study reports on which vaccine is more effective at reducing infection and protecting you from disease.
People who received the Pfizer COVID-19 vaccine had a 27% higher risk of infection and 70% higher risk of hospitalisation, compared to those who received the Moderna jab, a new study found. Both vaccines, however, provided high levels of protection, despite the difference.
The study was based on more than 439,684 US veterans who received either jab and were tracked over a period of six months. The findings are in line with a previous report that showed a higher SARS-CoV-2 binding antibody response among recipients of the Moderna vaccine, compared to recipients of the Pfizer vaccine.
According to the authors of the study, published on December 1st, 2021, their findings were consistent across different COVID variants.
“The 24-week risk of Covid-19 outcomes was low after vaccination with mRNA-1273 or BNT162b2, although risks were lower with mRNA-1273 than with BNT162b2. This pattern was consistent across periods marked by alpha- and delta-variant predominance,” the authors wrote.
According to the authors of this study, the differences reported may be due to a number of factors, like mRNA content in each vaccine. “A difference in effectiveness between the BNT162b2 and mRNA-1273 vaccines might be the result of the different mRNA content of the vaccines (100 μg for mRNA-1273 vs. 30 μg for BNT162b2),” they wrote in their report.
But the authors note that other factors may also be involved, like “the different interval between the priming and boosting doses (4 weeks for mRNA-1273 vs. 3 weeks for BNT162b2), or other factors, such as the lipid composition of the nanoparticles used for packaging the mRNA content,” the authors wrote.
Overall, however, the incidence of COVID-19 infection with either vaccine was very low, about 5.75 events per 1000 persons for Pfizer and 4.52 events per 1000 persons for Moderna. According to Dr Eric J. Rubin, Editor-in-Chief, The New England Journal of Medicine and Dr Dan L. Longo, a Professor of Medicine, Harvard Medical School in the USA, the key take-home message is the similarities in these two vaccines: they are both highly effective.
“We are lucky to have such good options. Vaccination with any vaccine is far better than remaining unprotected. The message is that the best vaccine is the one that’s available,” they wrote in an editorial.