Coronavirus The fourth vaccination does not seem to provide additional protection against omicron, Israeli researchers say – WHO and EMA do not recommend new rounds of vaccination

Preliminary According to research results, the fourth dose of coronary vaccination has little protection against self-infection or mild symptomatic disease, according to the news agency. Reuters mixed Health Policy Watch.

A study released on Monday tracked health workers in Israel, where a fourth round of vaccination is already underway. Less than 300 workers who received four doses of the vaccine were compared with a control group of 6,000 workers.

“Although the levels of antibodies increased significantly after the fourth dose of the vaccine, they only partially protect against omicron, which is relatively resistant to the vaccine,” commented the professor who led the study. Gili Regev-Yochay at the press conference.

“We already know that the level of antibodies needed to protect against omicron is probably too high to be achieved with the vaccine.”

When the resistance created by the third dose of vaccination was still significantly better than the second dose, after the fourth dose, the antibodies quickly returned to the same level as after the third dose. Those taking the four doses also had relatively the same number of infections as the control group.

“There may be a little more antibodies, but the difference to the third dose is not significant,” Regev-Yochay said.

“The result is good, but not what we expect from the effect.”

Fourth vaccination has been upwind more widely. According to the World Health Organization, scientific data do not currently support the fourth round of vaccination. The European Medicines Agency (EMMA) also announced a week ago that it does not believe there is a benefit to a fourth dose of the vaccine.

“Booster doses can be used as part of contingency plans, but repeated vaccinations at short intervals are not a sustainable long-term strategy,” said Emma’s Director of Vaccine Strategy. Marco Cavaleri at a news conference, according to the news agency Reuters.

The Agency also warned that continuing frequent vaccinations could also lead to an overload of the human immune system.

It’s about it is not a matter of the fourth dose of vaccine not working in principle as before, emphasizes the director of the Finnish Vaccine Research Center Mika Rämet.

“For example, I have received three doses. If I got a fourth now, yes, those antibodies would bounce up again for a moment, ”he says.

“But what good is that? Omikron bypasses antibodies in mildly infected patients. ”

According to Rämet, keeping antibodies so high that there is no mild illness is practically unrealistic. The body’s antibody level is always halved in about a month, and both delta and omicron conversion have multiplied the amount of antibody needed to prevent infection.

“The health benefits would be moderate for people under 70 in basic health. With Omikron, there is no longer any talk of herd protection through vaccinations, ”says Rämet.

Those who are immunocompromised or otherwise at risk may benefit from a fourth dose instead.

In the process Rämet reminds that the three rounds of vaccine that have already been done have not been wasted, and the protection they provide will not disappear into the air.

According to Rämet, the fact that the level of antibodies drops after a vaccine or a disease is part of the natural human defense system. The body seems to think that if there is no new exposure, the enemy who has moved in the community will be defeated and the troops may return home from the front.

However, the knowledge of the virus and the defense needed remains alive in the memory cells. When a similar intruder is again detected, the memory cells quickly restart antibody production.

“Memory cells recognize omicron after three doses of vaccination,” says Rämet.

Why, then, does our defense system not prevent mild self-inflicted disease?

The key reason is that the omicron variant is able to evade antibodies to vaccines.

In addition, the vaccine given by injection specifically stimulates the production of antibodies in the bloodstream, Rämet says, but other types of antibodies against the virus are needed in the upper respiratory tract.

Omikron can cause a symptomatic disease, even if the vaccine protects against a serious disease.

Agency of Medicines However, the mother is currently investigating whether there is a need for vaccines under development designed specifically against omicron.

Read more: Svenska Dagbladet: Biontech founders promise omicron customized vaccine by March

Rämet does not believe that the special self-vaccine should be distributed to the entire population. Omikron is now spreading so fast that the virus itself acts as a “live vaccine”. The majority of people suffer from a mild illness and gain immunity through it.

“The basic idea of ​​the vaccine is that it is taken before infection. For immunocompromised people, the omicron vaccine is welcome, it may not be necessary for basic health. ”

According to Rämet, it is possible that omikron itself will soon have to give way because of the widespread protection against it due to its rapid spread. It will be replaced by the next virus variant that will come up with a way to circumvent some of the protection. This is how the evolution of viruses works.

“In the future, I see vaccines that will be offered to smaller groups and over a longer dose range.