ASOURCE Navi

The fourth dose of the new coronavirus vaccine began on May 25 for people over the age of 60 and people over the age of 18 with pre-existing medical conditions. It is carried out for the purpose of preventing aggravation based on the duration of effectiveness of the vaccine after the third vaccination and the response situation in other countries.

The 4th vaccination is for those who have passed 5 months from the 3rd vaccination. Vaccines are made by Pfizer or Moderna. We decided to include people aged 60 and over as targets for the fourth “obligation to make efforts”. 18-59 years old with pre-existing medical conditions such as chronic respiratory disease, heart disease, kidney disease, diabetes in treatment or coexisting with other conditions, cancer treatment and immunocompromised individuals, Severe mental illness, obesity, etc. The method of sending vaccination tickets to people with pre-existing illnesses differs depending on the local government.

Using the Israeli Ministry of Health database, Pfizer's vaccine was used in approximately 1.14 million elderly people aged 60 and over to examine the effects of preventing infection and preventing the severity of disease. and those who received up to three doses were compared. The observation period is from January 15, 2022 to January 27, 2022 (effectiveness in preventing infection) and January 21, 2022 (effectiveness in preventing aggravation) during the epidemic of the Omicron strain. According to it, among those who received 4 doses of vaccination for 12 days or more, the number of people infected with corona was about 1/2 compared to those who were vaccinated up to 3 times, and the number of those who became severe was about 1/4. was. As the preventive effect against aggravation in the elderly declines with the passage of time after vaccination, booster vaccination is considered necessary.

Regarding changes in antibody levels that indicate infection prevention after 4 doses of vaccination, an Israeli study of 274 healthcare workers found that both Pfizer and Moderna were more effective after the 4th dose than after the 3rd dose. Antibody levels were high, but there was no significant difference. From this, it is thought that the infection prevention effect against the Omicron strain will not be significantly higher in the 4th time than in the 3rd time.

Regarding the side effects of the 4th dose, in the same Israeli study, after the 4th dose made by Pfizer or Moderna, local reactions were 80.3%, systemic reactions were 48.5%, the majority were mild and serious. It was not recognized, and there was no significant difference from the side reactions up to the third time.

Countries such as the United Kingdom, France, Germany, and Israel recommend the fourth vaccination, and only those who are at high risk of becoming seriously ill and medical personnel are eligible. As of March 21, (1) in the UK, people aged 75 and over who have had a booster vaccination for at least 6 months, elderly people living in nursing homes, and immunocompromised people aged 12 and over, and (2) in France, who have had a booster vaccination for at least 3 months. (3) Germany: people aged 70 and over who have been boosted for 3 months or more, immunocompromised people aged 5 or over, people living in nursing homes, and those who have been boosted for 6 months or more (4) Israel: People aged 60 and over who have been boosted for more than 4 months, high-risk people aged 18 and over, immunocompromised people, people in nursing homes, medical workers, and high-risk caregivers And so on.

Regarding whether or not it is necessary to continue to vaccinate after the fourth dose, the UK needs to consider additional vaccinations for people at high risk of severe illness in anticipation of the possibility of a coronavirus epidemic this winter. I'm assuming there is.