A group of Qatari and American doctors led by Leis Abu-Raddad, associate professor at the Qatari branch of Cornell University, decided to test how different vaccines cope with the COVID-19 delta strain.
The authors analyzed vaccinations for Qatari residents: 73% of citizens received two doses of Pfizer or Moderna between January and August 2021.
As a result, it turned out that both vaccines prevented a large number of infections, but their effectiveness was quite different.
According to scientists, the Pfizer vaccine failed to prevent about 300 cases of infection with the Indian strain, but the Moderna vaccine did not protect just over 50 people from infection.
Our observations show that the Pfizer vaccine was around 53% effective against the spread of the delta strain of coronavirus, while the Moderna vaccine was close to 85%. Both drugs reduced the number of severe cases and deaths from COVID-19 by 90-99.9%.
It is also noted that the number of hospitalizations and deaths from severe forms of COVID-19 has dropped to almost zero.