The fourth dose of COVID-19 vaccine is “safe” and “somewhat effective”, especially in the oldest and most vulnerable, according to early scientific data from Israel.
Quebec will soon follow in the footsteps of several European countries by authorizing the injection of a fourth dose against COVID-19. The acting national director of public health, Dr. Luc Boileau, is to make the announcement this week.
A first study on the subject was published in the New England Journal of Medicine. It specifies that this second booster dose is mainly effective against the symptoms of COVID-19, and not against infections. This fourth dose is intended for the elderly and immunosuppressed.
“At first they said it wasn’t increasing much [la protection], because we were tracking the antibodies. When we started tracking hospitalizations and all that, [les bénéfices] were clear,” points out André Veillette, researcher in immunology at the Faculty of Medicine of the Université de Montréal.
“Our results indicate that the maximum immunogenicity of mRNA vaccines is reached after three doses and that antibody levels can be restored by a fourth dose,” the scientific article mentions.
“Me, if I had the option of a 4th dose in the fall, I would go get it, adds Dr. Veillette. I am 62 years old. My nephew in his thirties? Maybe not. »
This Israeli study, not yet peer-reviewed, is based on data collected from 600 health care workers, 270 of whom received a fourth dose of the vaccine from Pfizer or Moderna four months after receiving their third dose. The results were compiled while the Omicron variant was circulating widely in the country.
This fourth dose is already offered to the oldest and most vulnerable in several countries: Denmark, Spain, Germany, Sweden, England and France. In Quebec, only people over the age of 80 should be allowed to receive this injection.
Dr. André Veillette sees this as a good sign from Quebec Public Health and hopes that this new dose will be deployed more quickly than the third dose last fall.
This text is taken from our newsletter “Coronavirus Mail” of March 21, 2022. To subscribe, click here.