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It seems like every day there is more bad news about the coronavirus variants.

There are headlines claiming that the variants are becoming more deadly, and stories warning that some variants could escape vaccines, trapping us in an endless pandemic. With every step forward – like the way millions of Americans are vaccinated daily – it feels like the variants are sending us back two steps.

A growing number of infectious disease experts are now saying the variant narrative got out of hand. Yes, several variants are circulating, and it is true that some seem more transmissible. Yes, we must continue to wear masks and protect ourselves and others until we get closer to collective immunity. But there is no definitive proof that any of the variants is more virulent, and there is currently no reason to believe that the variants will render our vaccines completely useless, infectious disease experts say.

Our immune systems are extremely complex, and while parts of the immune system may not respond as strongly to variants after vaccination, it won’t let us down as easily.

COVID vaccines help you make antibodies – and they trigger another immune response that fights the virus as well.

Much of the research regarding immunity to COVID-19 (which can be achieved either through vaccination or natural infection) has focused on antibodies. These little fighters attack the coronavirus and prevent it from binding to cells in our body and creating infection. Some laboratory studies found that antibodies do not do as well as anti-employment variants, which has raised concerns that vaccines may not be able to protect us.

But antibodies don’t tell the whole story. When people say antibody levels are dropping – and COVID-19 protection is wiping out – “that’s totally wrong,” said Jay levy, virologist and professor of medicine at the University of California at San Francisco.

The immune system is very complex, and in addition to antibodies there is a whole other aspect, known as the cell-mediated immune response, which is just as important, if not more so. This part helps create what are called T cells, which are essential for preventing infections. COVID-19 vaccines don’t just generate antibodies; they also cause your immune system to produce T cells.

“T cells are the main line of defense against the virus,” said Monica Gandhi, specialist in infectious diseases at UCSF. T cells can identify many different parts of the coronavirus (according to some studies 52 parts) and get rid of all virus-carrying cells. The cell-mediated immune response may also help our systems produce new antibodies if needed. Mutations or not, T lymphocytes will still be able to detect the virus and take action. “Your immune response is very complex, very robust and very extensive against several parts of the virus,” Gandhi said.

So why aren’t we all talking about the quality of T cells? They are really hard to measure, Gandhi said, while measuring antibodies involves a simple blood test. But the researchers to have examined the cell-mediated immune response in people vaccinated or with COVID-19, and the results are exciting.

On the one hand, all clinical trials of vaccines found that participants produced strong T-cell responses after vaccination, according to Gandhi. There is also proof that the variants probably won’t have a very significant effect on the immunity we get to be fully vaccinated. Two recent studies found that the T cell response was not affected by variants, and another The article found that while some antibodies decreased against the variants, our T cell response was maintained very well.

When it comes to COVID-19, a robust T cell response makes the difference between a mild infection and severe illness, research shows. Cells can’t always prevent an infection, but they may be able to clear it out quickly so you don’t get seriously ill. If you get the vaccine, “you don’t have to worry about getting infected – or if you do. [get infected], that you will have serious illness, ”Levy said.

“Your immune response is very complex, very robust and very extensive against several parts of the virus.”

– Monica Gandhi, Infectious Disease Specialist, University of California, San Francisco

How long will these T cells last?

At first glance, even if antibody levels decline over time, T cells are likely to protect us against variants for some time, especially with severe illness, according to Gandhi.

The coronavirus is expected to change drastically enough to totally evade recognition of the cellular immune response and render our vaccines useless. “The cellular immune response appears to be a little more diverse, or a little more inclusive, so that it can pick up small, small changes that a variant might have and still manage it,” Levy said.

The cell-mediated immune response can also have a long memory. Researchers tested the blood of people with the SARS coronavirus in 2003 and found that their immunity to T cells persisted until 17 years. The T cell response has also been maintained in people vaccinated against measles since 34 years old and cash.

COVID-19 is just over a year old, but early proof suggests that our T cells will last, although it’s unclear exactly how long. Some experts say we may eventually need boosters, and scientists are already working on it. But given durability of our cellular immunity, many infectious disease experts are thinking of boosters, at least in the near future, will be useless.

Researchers will continue to study how components of the immune system – antibodies, T cells and everything in between – deal with the coronavirus over time, but we know the immune system is robust and long-lasting when it comes to fighting it. viruses.

So if you are vaccinated, the next time you read a big title about a variant, breathe and think of T cells. “Know that T cells work against variants and you are fine,” Gandhi said.

Experts are still learning about COVID-19. The information in this story is what was known or available at the time of publication, but directions may change as scientists find out more about the virus. Please consult the Centers for Disease Control and Prevention for the most recent recommendations.


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