aNone of this data allows a comparison of the effectiveness of one vaccine against another: only these two companies have conducted, in Moderna’s case, new tests with a small group of 40 patients, and, in the case of Pfizer, reanalysis of data on infected and vaccinated people in two countries, Qatar and Israel.

But this data does share in dispelling some of the haze that has surrounded the variants for months: almost everything that has been written about the effectiveness (or ineffectiveness) of vaccines against these “mutants” has been based on observations that may be incomplete: the variables took a long time to become a statistically sufficient number. So that we have enough people who get vaccinated so that we can start comparing people who are infected with what. Qatar and Israel presented an opportunity because they very quickly vaccinated a large portion of their population.

According to two studies published by Pfizer, the vaccine will prevent the worst consequences of infection with B.1.1.7 (“British”) and B.1.351 (“South African”) variants, such as severe pneumonia, including in the elderly. Persons. The first study was published in New England Journal of Medicine, Based on an analysis of data for 200,000 infected people in Qatar between February 1 and March 21, during which time mass vaccination was in full swing. As of early March, almost half of these injuries were caused by the South African variant, and roughly the other half by the British. The second study published in The scalpel, Based on 230,000 cases of infection that occurred in Israel between January 24 and April 3. During this period, almost all infections in this country were caused by the British alternative, but despite this, the vaccine is said to have prevented about 95% of the infections.

The two studies also, in passing, confirm the importance of the second dose: in the Israeli case, the effectiveness of the Pfizer vaccine in preventing deaths would increase from 77% to 97%, from the first to the last, and the second dose.