U.S. scientists from Massachusetts and Minnesota researched effectiveness of mRNA vaccines during January to July 2021. That’s because they wanted to assess how well Pfizer and Moderna were doing against Alpha and Delta variants. Their report is pre-print and not yet peer reviewed. However, it does question Pfizer’s effectiveness with Delta strain.
Concerns Raised About Pfizer mRNA Vaccine Effectiveness
These findings could be a wake-up call for society lulled into a cocoon of complacency that all is okay now. The researchers found the Pfizer vaccine was only 42% effective against infection during July, when the Delta was center stage. A senior official in the current administration told Axios ‘If that’s not a wake up call, I don’t know what is’.
The study was a joint project between Mayo Clinic and Inference, an organization making biomedical knowledge computable. Here is a summary of conclusions highlighting their concerns over Pfizer effectiveness with Delta:
1… Moderna vaccine was 86% effective overall, compared to Pfizer’s 76%
2… Pfizer was 85% effective against hospitalization, Moderna was 92%
3… These results dropped sharply in July, when Delta was 70% prevalent in Minnesota
4… At that time Moderna was 76% effective against infection, compared to Pfizer’s 42%
The Inference and Mayo Clinic researchers found similar results in other states. The infection risk of people with both Moderna shots was 60% lower than with Pfizer in Florida, for example.
How Concerned Should We Be About Pfizer Effectiveness With Delta
The report concludes ‘both mRNA vaccines strongly protect against COVID-19 infection and severe disease’. However, the authors do call for further evaluation against the differences they highlight. And they also suggest ‘further evaluation of mechanisms underlying differences in their effectiveness, such as dosing regimens and vaccine composition’.
It’s evident we are following an unfolding story that may never reach a point when we could say ‘case closed’. Vaccines help us after a virus enters our bodies. It’s our job to prevent this happening by taking sensible precautions. People who refuse vaccines, and ignore this advice are placing themselves and others at high risk. Vaccines should be our last, not our only resort.
Recent
Pfizer Vaccine Counters Delta But Rates Vary
The Delta Variant Dominating COVID-19
Preview Image: Swiss Cheese Pandemic Defense
Preprint Report on mRNA Effectiveness