COVID-19. Towards a third dose of the vaccine for everyone?

There is a lot of conflicting information circulating about the third dose of the vaccine against COVID-19. French people over 65 years of age or already suffering from comorbidities are affected by this booster dose, six months after the last injection. This campaign aims to enhance the immunity of the most vulnerable groups and those most at risk of serious disease. But soon a larger part of the population can be affected.

What do the authorities say?

An American study published in the scientific journal The Lancet on Tuesday confirmed that the effectiveness of the Pfizer / BioNTech vaccine decreases over time. The vaccine reduces the risk of infection by up to 88% within a month of injecting the second dose, but prevents only 47% of infections after six months, according to this study. On the same day, the European Medicines Agency (EMA) approved a booster dose for administration of Pfizer to all adults, which “would increase antibodies” six months after the second dose and four weeks after a single injection of Janssen.

But the government is not obligated to follow this position and is waiting for new advice from the Haute Autorité de Santé, which is expected in the coming days. In its last opinion, which was submitted in August, the health authority decided to conduct a third injection for the most vulnerable groups, but also noted that the decline in the effectiveness of the vaccine over time “is not only the elderly and the population at risk of contamination.” dangerous forms.” So a third could benefit everyone after a certain number of months (between six and eight months, depending on the studies), except for people aged 12 to 17, who were not currently involved.

Too early for the experts

“We’re not going to make a third dose for everyone, at least not now,” said Professor Jean-Daniel Lelliver, a HAS expert and immunologist who specializes in vaccines. But the third dose can be validated early for some populations, such as health care providers, who are more susceptible to contracting the virus, for example.

At the moment, it has already summoned about a million people, but tens of millions of French under the age of 65 are waiting to see if they will be affected soon. In Israel, a country that has previously vaccinated its population, the third dose campaign for those over the age of 12 began this summer. In the USA, Joe Biden announced a massive recall for adults in September, before they were contradicted by experts at the Centers for Disease Control and Prevention (CDC), who estimate that the third dose is currently recommended only for the elderly and frail. and the vulnerable (caregivers, prisoners, etc.).

What about poor and weak countries?

Extension of the third dose to the entire population also depends on the balance of benefits and risks. The European Medicines Agency noted in its report that there is still no data available on the side effects of the stimulant dose. “The risk of developing inflammatory heart disease or other side effects after taking a booster dose is extremely rare, unknown and carefully monitored,” the European Medicines Agency said. Rare cases of myocarditis have already been identified in patients receiving the Pfizer vaccine.

In addition, the third dose of the vaccine is still not a priority for the World Health Organization as long as the vaccination rates in the world have not increased, especially in countries with economic difficulties. “At this point, we don’t want to see widespread use of booster doses for healthy people who have been fully vaccinated,” WHO Director-General Tedros Adhanom Ghebreyesus said on September 8. The president said the goal is for each country to be able to vaccinate at least 40% of its population by the end of the year.