The COVID-19 vaccine remains effective as the number of mutants increases

There is plenty of evidence from both clinical trials of vaccines and in the real world to demonstrate the ability of vaccines to protect us from mutants.

Recently the study A Pfizer study found that 44,000 people worldwide, including South Africans, were primarily exposed to the B.1.351 variant, and that the vaccine was 100% effective against severe illness and death. ..

Real World data It also shows that the Pfizer vaccine countered the first detected B.1.1.7 variant in the United Kingdom. Even in areas where B.1.1.7 was the predominant strain, Shot was 97% effective against symptomatological COVID-19, hospitalization, and death.

Evidence shows that the same is true modern, AstraZeneca,and Johnson & Johnson vaccine.

Clinical trials of the Johnson & Johnson vaccine were conducted in South Africa and Brazil. When the test was conducted, both were hit by the B.1.351 and P.1 variants, respectively.

Although the Johnson & Johnson vaccine was generally less effective against mild to moderate illness in South Africa and Brazil, a single dose was able to strongly prevent hospitalization and death.

If you look at areas with high vaccination rates like England And IsraelYou can see that cases and hospitalizations are in free fall, even in the presence of variants.

The main point is that the vaccine works well against mutants, especially when it comes to preventing serious illness and death.

There are some Laboratory research Infectious disease experts have broadly agreed that antibody measurements do not provide a complete picture of protection, showing that the initial antibody response appears to weaken in the months following vaccination.

Explain that the immune system is complex and antibodies alone cannot determine how well you are protected from pathogens. Dr. Joseph Craft, Professor of Immunobiology and Medicine, Yale University School of Medicine.

Cell-mediated immune responses, including B cells that produce antibodies with T cells, also show a strong response to pathogens and often last for years.

Our antibodies help prevent the outbreak of infection by neutralizing the virus, but T cells can recognize some of the virus on infected cells and clear the infection before it becomes serious. ..

“This is not surprising because the T cell response is much broader than the B cell response to vaccinated patients, and T cells recognize multiple parts of the virus,” Craft explains. ..

Studies show that T cells can be identified 52 parts Even if there is a mutation in the coronavirus T cells still recognize Attack the variant.

According to Craft, the detectable antibody response is usually reduced with other viruses. However, memory B cells and T cells usually survive and can fight well when exposed to pathogens in the future.

I don’t hear much about T cells because they are more difficult and expensive to measure than antibodies. Dr. Monica Gandhi, An infectious disease specialist at the University of California, San Francisco.

“Antibodies are dimes. That’s why we do antibody tests after antibody tests because they are so easy to measure,” Gandhi said.

But scientists say with T cells data Show all vaccines — Pfizer, Moderna, and Johnson & Johnson — Brought a strong T cell response to participants.

All vaccine clinical trials have shown that “our T cells are elevated with the vaccine. All these stories tell us that T cells act on mutants.” Said Gandhi.

According to Craft, when our body is exposed to a virus, we are usually protected from the virus for a long time.

the study For measles immunity, measles-specific T cells have been shown to last up to 34 years. In patients with SARS, the coronavirus behind the 2003 epidemic, T cells 17 years So far.

Early evidence It suggests that coronavirus-specific T cell responses are also sustained.

Recently paper Variants containing B.1.1.7, B.1.351, P.1, and CAL.20C were determined to have no significant effect on T cell responses.

The study found that people “have a strong T-cell response to these mutants that is comparable to the T-cell response obtained from ancestral strains,” Gandhi explained.

another Research Due to their skill, T cell immunity has proved to be potentially the greatest weapon in avoiding serious illness. Remove the virus quickly..

Scientists need to continue their research on T cell immunity to understand how protective and durable our cell-mediated reactions are.

“Memory isn’t perfect. That’s pretty good, and that’s one of the reasons we’re long-lived mammals,” says Craft.

There is growing concern that variants may evade our vaccine, but many infectious disease doctors say there is optimistic reason.

Even if antibody levels drop in the months following vaccination, the immune system is complex enough that vaccinated people are well protected from mutants and have a lower risk of illness, hospitalization, and death. I will.