Israeli studies show that a total of four additional doses after booster vaccination is not sufficient to combat Omicron strains

The new coronavirus vaccines of Pfizer and Moderna are said to be 'completed' by inoculating twice, but the efficacy rate of the vaccine gradually decreases over time, so the

third booster vaccination ( Booster vaccination) is recommended. However, an Israeli study of the highly infectious variant of the new coronavirus, the Omicron strain , found that 'a total of four vaccinations following the third vaccination is inadequate. The result was shown.

Israel Trial Suggests 4th Dose Not Warding Off Omicron Infection --Bloomberg

Israeli study shows 4th shot of COVID-19 vaccine less effective on Omicron | Reuters

Israel study: 4th vaccine shows limited results with omicron --ABC News

Israel started vaccination with the new coronavirus vaccine in December 2020, and is the fastest-paced country in the world. After completing two inoculations to a large number of people as soon as possible, in August 2021 due to the epidemic of Delta strains , the booster inoculation, which is the third inoculation in total, was started. According to a subsequent survey, 'Booster vaccination reduces the risk of infection by 10 times, the risk of aggravation by nearly 20 times, and the mortality rate by 90% compared to the state of being vaccinated twice.' The results are shown .

However, the Omicron strain reported in November 2021 is extremely infectious, and cases of infection with the Omicron strain have been reported even in people who have already been vaccinated three times. In response to these circumstances, Israel is the 'total of four round of vaccination,' the world's first from 2021 December has started .

The Israeli medical institution, Shiva Medical Center, has given a total of more than 270 staff members a total of four vaccinations and investigated their effectiveness. All healthcare workers who participated in this experiment were vaccinated with the Pfizer BioNTech vaccine three times, 154 were vaccinated with the same Pfizer BioNTech vaccine the fourth time, and 120 were vaccinated with the Moderna vaccine the fourth time. Did.

The research team did not receive the fourth vaccination when the group vaccinated with the Pfizer BioNTech vaccine was given two weeks after the fourth vaccination and the group vaccinated with the modelna vaccine was given one week after the fourth vaccination. The amount of antibody in the body was compared with that of the group. As a result, it was confirmed that the antibody level was 'slightly higher' in both groups compared to the group that did not receive the fourth vaccination.

However, it has been pointed out that the increase in antibody levels due to the fourth inoculation is insufficient to protect the Omicron strain. 'Despite the increased antibody levels, the fourth vaccine provides only partial protection against the virus,' said Dr. Gili Regeb Yohai, director of the Infectious Diseases Division at the Shiva Medical Center. It was effective against mutant strains, but less effective against Omicron strains. '

Dr. Regeb Yohai said in an online press conference that the decision to vaccinate people most vulnerable to the new coronavirus infection (COVID-19) for the fourth time was correct, but the results are 'all.' It claims that it does not support the 'deployment of the fourth inoculation to the population'. 'The fourth vaccination restores antibody levels to the original levels of the third vaccination, which is very important, especially in the elderly,' said Nachman Ash, director of the Israeli Ministry of Health. He said the results of this study would be taken into account in the discussion of whether to deploy a fourth dose to a wider population.

In Israel, the fourth vaccination is being promoted for elderly people in their 60s and over, and at the time of writing the article, more than 500,000 people have been vaccinated for the fourth time.

in Science, Posted by log1h_ik