The efficacy of Pfizer and Modern vaccines is reduced to 66% against the delta type

These data come from a study of thousands of health center and hospital staff in six states to study the effectiveness of vaccines in real terms. Participants are tested weekly for both symptomatic and asymptomatic infections.

The effectiveness of the Pfizer and Modern vaccines against Govt-19 infection has dropped from 91% to 66%, dominated by delta variability in the United States, according to data released Tuesday by U.S. health officials.

The data comes from a survey of thousands of health center and hospital staff in six states to study how vaccines work under real conditions. Participants are tested weekly for both symptomatic and asymptomatic infections. Almost all vaccinated health workers received sera from Pfizer or Moderna.

Intermediate data

Between December 2020 and April 2021, the effectiveness of vaccines in preventing the disease was 91%, according to data released by the Centers for Disease Control and Prevention (CDC), the country’s leading public health agency.

But in the weeks when the delta variant dominated, that is, when it was responsible for more than 50% of cases per sequence, the efficiency dropped to 66%.

The authors of the study warn that this decline will not only be caused by delta variability, but may also lead to a decline in performance over time.

“Although these interim data suggest a moderate reduction in the effectiveness of the Covit-19 vaccine in preventing infection, the fact that the incidence of infections is less than two-thirds underscores the continued importance and benefits of the vaccine.” .

The data released on Tuesday did not differ between the effectiveness of the Modern vaccine and Pfizer’s serum. Corinne Le Coff, commercial director of Moderna Labs, on Tuesday evening triggered a drop in performance against the different delta variations between the two vaccines on our antenna: “76% for Modernna and 54% for Pfizer.”

Severe cases, hospitalization and protection against death

This performance decline against the delta variance has been pointed out by several studies, even though the exact number varies from one to another.

This is one of the reasons health officials put forward last week to announce a withdrawal campaign from mid-September, which will affect all American adults who received a second dose eight months ago.

The safety of vaccines against the serious incidence of disease, hospitalizations and deaths is high, officials insist.

Another study released Tuesday by the CDC, conducted in Los Angeles from the beginning of May to the end of July, shows that those who are not vaccinated are 29 times more likely to be hospitalized than those who are not vaccinated.

Delta dominated the United States in early July and is currently responsible for more than 98% of epidemics.