Covid – Delta variant: a study finds the Pfizer vaccine is less effective in the long-run than AstraZeneca

Published by Laurent de Sortiraparis · Published on August 20th, 2021 at 04:06 p.m.
The Pfizer vaccine is less effective in the long-run against the Covid Delta variant than AstraZeneca… This is the conclusion reached by a study issued this Thursday August 19, 2021 carried out by scientists from the Oxford University. But both vaccines are yet “highly” effective.

This is food for thoughts… This Thursday August 19, 2021, scientists from the Oxford University uploaded on their website a study showing the performances of the Pfizer and AstraZeneca vaccines against Covid Delta variant. The latter have discovered that the Pfizer vaccine is more effective than AstraZeneca against the Delta variant, but is less effective in the long-run.

What was the study about then? Scientists from the Oxford University have assessed samples collected between December 2020 and August 2021 in over 700,000 volunteers. They have noticed the Pfizer vaccine is effective for high-viral load infections, 90% effective against the Delta variant one month following the second dose of vaccine, then 85% two months after, and 78% three months after.

As for the AstraZeneca vaccine, results are different. It is 67% effective one month after the second shot, 65% after two months, and 61% after three months. After five months, whether it applies to Pfizer/BioNTech or AstraZeneca, the protection level is similar. Data show decline for the Pfizer vaccine, as Dr. Koen Pouwels – who worked on the study – says.

But yet, you do not need to worry… And for good reason. As both vaccines “generally show high effectiveness”, Pouwels goes on. Data also applies to the level of overall protection, but not against severe disease and hospitalization, that yet are more interesting to study to determine the real effectiveness of vaccine. The study now has to be peer-reviewed.

Practical information
Comments