To achieve ‘70% collective immunity’… “In fact, 90% of the nation should be vaccinated

As the new coronavirus infection (Corona 19) vaccination approaches 5 days in the future, attention is focused on how many populations need to get the vaccine in order to secure collective immunity.

According to health authorities on the 21st, it is known that population immunity is formed only when 70% of the total population has antibodies.

In an emergency questionnaire in the National Assembly in January, Jung Eun-kyung, the head of the Korea Centers for Disease Control and Prevention, said, “It is believed that about 60-70% of the entire population must acquire immunity (group immunity).”

Accordingly, the government is setting a goal to form a collective immunity by November after the first vaccination is administered to 70% of the population by September, starting with workers in nursing hospitals, medical welfare facilities for the elderly, and high-risk medical institutions.

If the population of Korea is about 52 million, it is calculated that at least 36.4 million people need to be vaccinated.

Of course, this assumes that the vaccine has 100% antiviral effect. However, in reality, the average preventive effect of the five vaccines (AstraZeneca, Janssen, Pfizer, Modena, and NovaVax) supplied domestically is around 80%.

In addition, children and adolescents and pregnant women under the age of 18 are excluded from the vaccination target themselves due to lack of clinical trial results, and there is public opinion that they will not receive the vaccine.

◇ “It is different from achieving 70% vaccination rate and 70% group immunity”… 3 out of 10, negative for vaccine

Kim Woo-joo, a professor of infectious medicine at Daegu Guro Hospital, said on YouTube, “You should not misunderstand `70% of the population’ as `70% collective immunity`.” It means that 70% should have a protective immunity to defend against Corona 19, that is, a’neutralizing antibody’.”

This is because the preventive effect of the currently developed vaccine is less than 100%.

When looking at the results of clinical trials of five vaccines introduced in Korea, the preventive effect varies from at least 62% to a maximum of 95%.

Looking at the preventive effect of each vaccine type, AstraZeneca, which is the first to be supplied to Korea, is 62-70%, Janssen 66%, NovaVax 89.3%, Modena 94.1%, and Pfizer 95%.

If the average preventive effect of these vaccines is calculated as 80%, it is concluded that it is possible to achieve 70% collective immunity only when 46.2 million people, which are 89% of Korea’s population, receive vaccination.

Earlier, the government announced that it plans to vaccinate a total of 43.55 million people by the fourth quarter of this year through the’Corona 19 Vaccination February-March Implementation Plan’. This is about 84% of the total population.

Considering children and adolescents under the age of 18 who are excluded from vaccinations, pregnant women, and those who do not wish to be vaccinated, almost the entire population should receive vaccinations.

In fact, there are many negative views about vaccination.

As a result of a survey by Professor Yu Myung-soon of Seoul National University’s Graduate School of Public Health on 1,68 adult men and women on the 5th to 7th, 3 out of 10 answered that they would postpone or refuse vaccination.

Looking at the content of the survey, 26.8% of respondents said, “I want to postpone the timing and order of vaccination to the next,” and 4.9% said that they will refuse vaccination. It is estimated that 31.7% of all respondents had a negative view of vaccination.

This is also happening in Israel, the world’s fastest vaccinating country.

According to Professor Kim, the U.S. is the first in the absolute amount of vaccination by country, but Israel has the highest vaccination rate per 100 people at 78%.

Professor Kim said, “In Israel, people who could be vaccinated quickly started vaccination, but there were about 20% of the’concrete layer’ that refused to be vaccination, so at some point (vaccination) progress was difficult. I can see it.”

◇ Expert “Pregnant women and juvenile vaccinations seem to be difficult…I need to hurry vaccination before the spread of the South African mutant virus”

Experts believe that more than 80% and close to 90% of the population should be vaccinated to form collective immunity.

Professor Seol Dae-woo of Chung-Ang University College of Pharmacy said, “The vaccines have different preventive effects and the amount of vaccines entering Korea is different. Only 80-85% of the population will achieve 70% of collective immunity.” “If you consider those who are difficult to get vaccination because they don’t have them, or those who refuse because of fear of religious beliefs or side effects, it will be possible only if they are correct.

Prof. Seol predicted that future vaccinations would be difficult because it would be difficult to realistically proceed with vaccination for children under the age of 18 and pregnant women.

“As the vaccine was developed quickly, few manufacturers have conducted clinical trials for pregnant women or under the age of 18,” he said. “In particular, in the case of Pfizer vaccine, people with a history of allergies to prevent delay in vaccine development due to side effects in the clinic. Until the clinical trial was excluded,” he explained.

However, Professor Seol said, “If the number of people who received the vaccine increases as a result of the (government) vaccination, 70% of the population immunity is possible because it induces the vaccination itself.” “There should be no death cases.”

Prof. Seol also mentioned that there were several deaths after vaccination in Norway. “Unlike Pfizer so far, the AstraZeneca vaccine did not cause death after vaccination and had fewer severe side effects.”

Prof. Kim Woo-joo also predicted, “As is known, it is expected that 80% or more of the population, rather than 70% of the population, must be inoculated to achieve the intended purpose (formation of group immunity).”

“Through data from Israel (which is the leading vaccination rate), we will be able to see what percentage of the population in a country needs to be vaccinated to form collective immunity,” he said. “We only use one vaccine, and we are trying population immunity with 5 vaccines with different efficacy.”

Professor Kim emphasized that as mutant viruses that can neutralize the vaccine have emerged, it is necessary to hurry to complete vaccination before the mutant species spreads further to block further infection.

Professor Kim said, “If a mutant virus originating from the Republic of South Africa goes into an outbreak, the AstraZeneca vaccine that we need to use at this time could be a problem because it is not effective. The government actively blocks the outbreak of mutant virus, and at the same time You should also pay attention to securing a vaccine that prevents it,” he advised.

He continued, “Out of 99 patients with mutant virus infections identified in Korea, 80 were from the UK, 13 were from South Africa, and 6 from Brazil. We hope the mutant virus will not be outbreaks, but the vaccine we have secured “It is advantageous for us to have a lot of mutations from the UK that can be expected to be effective.”

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