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One dose of mRNA COVID-19 vaccine is enough after being infected. Since the COVID-19 pandemic in early 2020, more than 200 million people around the world have been infected with COVID-19. So what should they do for those people who have been infected with COVID-19? Do they need to be vaccinated? If necessary, do I have to get two more doses of vaccine?
On August 6, 2021, researchers from Rush University Medical Center and Abbott Corporation published a titled SARS-CoV-2 Antibody Responses in Infection-Naive or Previously Infected Individuals After 1 and 2 in JAMA Open Network. Doses of the BNT162b2 Vaccine research paper.
The study observed that people who had previously been infected with the new coronavirus had a level of antibodies produced after receiving one dose of Pfizer mRNA vaccine, which exceeded the level of two doses of uninfected people. Moreover, two doses of mRNA vaccines for previously infected people did not further increase antibody levels.
Therefore, the research team concluded that for people who have previously been infected with COVID-19, only one dose of the vaccine is enough to obtain a strong immune response and protection.
This small study included 29 people with COVID-19 infection confirmed by PCR tests and 30 healthy people. The average age of the participants was 42 years old, and about three-quarters of them were women.
First, the research team tested the level of antibodies against the new coronavirus in the blood of participants who had previously been infected with COVID-19, and found that the previous infection caused them to produce antibodies, but the average antibody level was only 621 AU/ml, which was not enough to resist COVID-19. Of re-infection.
After these participants who had previously been infected with COVID-19 were vaccinated with the first dose of vaccine, their blood levels of protective antibodies against the COVID-19 virus soared to 30,000 AU/ml, which was enough to protect them from the COVID-19 infection. After the second dose, the antibody level Only increased to 37000AU/ml.
For participants who had not previously been infected with COVID-19, after the first dose of vaccine, the level of protective antibodies in the blood was only 1800 AU/ml, and after the second dose, it increased to a protective 15000 AU/ml.
Based on the above test results, the research team concluded that for people who have never been infected with COVID-19, the level of protective antibodies produced by one dose of the vaccine is insufficient, so two doses must be given to produce sufficient protection.
For people who have previously been infected with the new coronavirus, one dose of vaccine has produced enough protective antibodies, so only one dose of vaccine may be enough.
The research team said that this research has an important role in promoting vaccination in many places around the world, because some people who have been infected with COVID-19 are hesitant to vaccines. They feel that they have been infected and have developed protective antibodies, so they no longer Need to be vaccinated.
This study reminds everyone that people who have previously been infected with the new coronavirus do have protective antibodies in their bodies, but the level of protection is insufficient. They still need to be vaccinated to improve the protection effect, but they only need one dose to produce enough protection. Effect.
(source:internet, reference only)