Over 98% of residents have antibodies against COVID-19 | Health
Ho Chi Minh City (VNA) – According to the Ho Chi Minh City Health Department, in September the research team carried out random sampling with a high level of representativeness in terms of age (from 0 to over 70), gender and different geographical areas across the city’s urban territory.
Serum samples were collected from 839 people to measure anti-protein N antibodies to assess the percentage of people with SARS-CoV-2 infection and the percentage of people with anti-protein S antibodies (anti- Spike protein) to assess people who already have protective/preventive antibodies due to COVID-19 vaccination or previous infection.
Result: 88.2% of 839 serum samples had antibodies against protein N; it is 98.7% of inhabitants having antibodies against protein S from natural infection or vaccination.
According to the Ho Chi Minh City Health Department, antibodies against the N protein only appear from a natural infection with COVID-19 or after vaccination with the inactivated Sinopharm vaccine. However, in Ho Chi Minh City, the Sinopharm vaccine has been used in a very limited way and is not used for groups under 18 years old.
The anti-N antibody positive rate in different age groups has a fairly similar distribution: from 86% to 97% in age groups from under 5 years to under 70 years. Particularly for the 70+ age group, this rate is 76%. This result is similar to the results of a study evaluating the immune response of medical staff at the Hospital for Tropical Diseases carried out in November 2022 (371 out of 400 medical staff surveyed were infected with the SARS-CoV-2 virus, representing 93 %).
From this, it can be concluded that in September 2022, 88% of the inhabitants of Ho Chi Minh City were infected with SARS-CoV-2. In general, based on the epidemiological situation of Ho Chi Minh City and the opening time of schools after the Lunar New Year (March 2022), at the same time as the appearance of the Omicron mutation, we can determine that the Omicron wave is the main cause of natural infection of the inhabitants of Ho Chi Minh City.
About 98.7% of the population have antibodies against protein S (from natural infection or vaccination). This rate is also quite similar across all surveyed areas of Ho Chi Minh City. The high rate of residents with antibodies indicates vaccine coverage as well as the role of natural infection in creating antibodies against SARS-CoV-2 in the community.
Only a very small percentage (1.3%) of the inhabitants do not have antibodies against protein S (antibody levels are below the detection limit of the test technique), but this does not mean that they are not protected against SARS-CoV-2 because this survey does not assess the cellular immune reaction (if there is a cellular immune reaction, as soon as the virus enters the body, memory B cells activate immediately and produces antibodies, and the T cells also activate and destroy the virus).
When analyzing levels of anti-protein S antibodies in the 12 and under age group, results show that this group tends to be lower than other age groups. This is also consistent with the fact that vaccination coverage in this group is lower than in other age groups. Currently, scientists around the world are still learning the threshold of positive antibodies to ensure the level of protection against the Omicron mutation. There is not enough scientific basis to determine this.
The research team will continue to study the serologies in the community during the period of December 2022 and the relationship between antibody data and disease severity levels according to age groups in Ho Chi Minh- City to further assess the effectiveness of herd immunity against SARS-CoV-2.
Although the rate of residents with antibodies to prevent the COVID-19[feminine] be high, the health sector in Ho Chi Minh City is calling on people to shoulder the same responsibility to protect and maintain herd immunity against COVID-19 by getting vaccinated against COVID-19 if they don’t get it. have not been, and receive boosters and additional injections in accordance with regulations.
According to the Municipal Health Department, after the period when the city became the most serious outbreak of COVID-19, scientific research to assess the level of herd immunity of people in Ho Chi Minh City is an important requirement. and very convenient, especially after the period when the whole city made great efforts to implement COVID-19 vaccination activities for city residents.
It is very important to know the percentage of people who are immune to the SARS-CoV-2 virus (because they contracted the disease or were vaccinated), as a scientific basis for convincing people to get vaccinated if the level of antibody is not high enough, and at the same time, it is also a scientific basis for calling people to do boosters according to regulations to maintain immunity if the antibody level at the time of the investigation is already at a community protection level. -CVN/VNA
#residents #antibodies #COVID19 #Health