After two doses, the Pfizer vaccine prevents more than 95% of severe cases – Revista Galileu

Two doses of the Pfizer / BioNTech vaccine are able to provide more than 95% protection against infections, hospitalization and death by Covid-19, according to the first study to evaluate the effectiveness of a double dose of immunity in the context of vaccination in pasta. Published in the journal The scalpel On Wednesday (5), the analysis used data from the Ministry of Health in Israel, a country that has already fully immunized more than half of its population against the novel coronavirus.

With about 9 million inhabitants, Israel was one of the first countries in the world to start the vaccination campaign against the emerging corona virus, which began on December 20, 2020. As of April 3, 2021, the period specified in the analysis was 72% of People over the age of 16 and 90% of those over the age of 65 have already received two injections of Pfizer / BioNTech – the only one administering in the Jewish state – equivalent to over 5 million people.

During the investigation period, from January 24 to April 3, 2021, the strain most prevalent among the disease cases in the country was B.1.1.7, also known as the UK variant. It is considered more transmissible, as it represented 94.5% of samples collected through PCR tests in Israel. But according to the observational study, the strain did not prevent the immunization device from providing 95.3% protection against infection with the new coronavirus and reduced the risk of death by the pathogen by 96.7% within seven days after the second dose.

The vaccine also proved highly effective in protecting against disease progression: it reduced overall hospitalization by 97.2% and hospitalization for severe cases by 97.5% – including among the elderly. In people over the age of 85, seven days after the administration of the second dose, the immunization device provided 96.9% protection against hospitalization, in addition to reducing the risk of death by 97% and the possibility of infection by 94.1%.

In the 16-44 age group, the product prevented death by 100%, reduced hospitalization by 98.1%, and reduced incidence by 96.1%. Prevention also prevented symptomatic and asymptomatic infection in 97.0% and 91.5%, respectively.

According to the study, the levels of protection observed between seven and 14 days after receiving the first dose, although relatively high, were significantly lower compared to the safety provided by the two syringes: 57.7% against infection, 75, and 7% against hospitalization and 77% against death. “It is possible that a single dose of the immune system provides a shorter protection window than two doses, especially in an environment where new variants of Sars-CoV-2 continue to emerge,” he warns. document.

The associations observed between the decrease in Covid-19 cases in Israel and the periods in which a high rate of vaccination was observed for each age group also indicates that the blanket immunization program – not the lockdown that began on December 27, 2020 – was also key to controlling the epidemic. At the national level, especially among the elderly.

This is because, until mid-January 2021, the number of new coronavirus infections among people over the age of 65 continued to increase, until the second dose began in the country, and daily cases decreased from 55 to about 30 per 100,000 days 7 February, a date that corresponds to the first phase of the reopening in the country. As more citizens received two injections of the immune system, similar patterns were also identified across all age groups.

Hopes

The study considers that future research focusing on the long-term effectiveness of the Pfizer-BioNTech vaccine will play a vital role in better understanding its potential in combating Covid-19. Additionally, given the different pandemic scenarios observed around the world, the authors caution that countries should be cautious when generalizing the data observed in Israel and suggest similar analyzes be undertaken elsewhere.

But data in the Jewish state does not fail to bring hope – and reinforces the central role of mass vaccination in dealing with Covid-19. It concludes, “Collectively, these results indicate that the high uptake of the vaccine can substantially contain the epidemic and provide hope for the ultimate control of the outbreak of SARS-CoV-2 with the increase in vaccination programs in the rest of the world.” Research.