Your Immunity to COVID-19 could last longer than you think
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There are signs all over the globe that immunity to SARS CoV-2, which is the coronavirus responsible for COVID-19, does not last long after vaccination.
Five months after vaccinations were given to the majority of Israel's population, Israel now has one of the worst COVID-19 spikes in history. In the United States, health officials recommend a booster shot eighteen months after the initial vaccine course.
How long does immunity last following two doses? It could last six months. How much protection do you have left after that?
It all depends on the type of immunity being discussed, according to Ali Ellebedy, an immunologist at Washington University in St. Louis. Your body might be more prepared to fight the coronavirus six months after you have received your vaccine than you think.
Ellebedy says, "If you were vaccinated six-months ago, your immune system trained for six months to be better prepared to fight a COVID-19 infected."
Ellebedy claims that several new studies have shown that mRNA vaccines such as Moderna and Pfizer BioNTech trigger the immune system to provide long-term protection against severe COVID-19. This protection is likely to last for many years, if not longer.
Let's suppose you were given the Moderna or Pfizer second vaccine six months prior to his comment. Your immune system immediately started producing antibodies and got to work.
These antibodies act a little like archers in the castle's moat. They are found in your throat and lining, ready to kill any SARS-CoV-2 particles trying to get into your moat (aka your nasal tissues).
According to Deepta Bhattacharya, a bioimmunologist at the University of Arizona, these antibodies can prevent infection. They prevent the virus from infecting cells and setting up shop. They provide the body with its first-line defense.
However, the initial round of antibodies can be a bit slow after vaccination. The antibodies are a little sluggish. Bhattacharya states that they are not well-trained to kill SARS-CoV-2 and they don't last very long.
The blood's level of antibodies begins to fall about a month after the second dose of mRNA. A study published in Nature in June showed that antibodies begin to degrade and cells that make them cease to exist.
Bhattacharya states that this happens with all vaccines, regardless of whether they are for COVID-19 or the flu. "In each immune response there is a sharp increase in antibodies and then a period when it begins to settle down into a more stable level.
Media has focused largely on the decline in antibodies as the reason for "waning immunity." Bhattacharya claims that the combination of this decline in antibodies and the high potency delta variant of the virus, which has been dominating many countries this past year, is increasing the risk of infection for fully vaccinated individuals.
He says, "If you get a large dose of delta as the variant often gives it, the virus may slip past the initial barrier of antibodies." "So I believe we are starting to see some of those signs. However, the level of breakthrough infections is not as high as it seems.
Why? It's because the media has mostly ignored key facts about antibodies eight months after vaccination. Bhattacharya states that they are stronger than the antibodies triggered by the vaccine.
The first round of antibodies (archers) was out protecting the moat of your castle (respiratory tract). But the immune system wasn’t just waiting for those soldiers to be enough. It was instead busy training more archers and foot soldiers.
The immune system creates a training center in your lymph nodes after the second shot. This allows special cells to learn how to produce stronger antibodies.
"The antibody's quality improves with time. Bhattacharya states that it takes far fewer new antibodies to protect you. He adds, "So I believe that worrying about the decline of antibody is not something that's very productive."
He also said that the cells responsible for making these souped-up antibody become more souped up. They learn how to make powerful antibodies in the training center.
Bhattachurya states that these cells are "remarkable." They produce 10,000 antibodies per second, according to estimates. These cells are sufficient to protect you from future infections.
"We have done back-of the-envelope calculations to determine how many cells are required to protect a mouse against a deadly infection. Bhattacharya states that it's three. "Of course we are bigger than mice. You get the feeling that it doesn’t take many people to provide good protection.
These cells also learn how to persevere in the training center. Ellebedy, an immunologist, says that they are essentially given the gift to eternal life.
His colleagues and he discovered that six months after vaccination, the antibody-producing cells move into the bone marrow. They can survive for many decades and even a lifetime. Researchers discovered antibodies that could neutralize 1918 flu symptoms in people who had been exposed to it 90 years ago.
Ellebedy states that they have found these cells in bone marrows of people infected by SARS-CoV-2. "We are now finishing research to show these cells also appear in bone marrow following vaccination."
Ellebedy states that long-lived plasma cells are known as long-lasting antibodies cells. They will likely release antibodies into the blood for many decades. This will provide long-term protection from SARS-CoV-2. These antibodies will not be as effective if COVID changes.
Ellebedy states that although the antibodies are kept at very low levels, they are still essential for protecting against infection. These antibodies can slow down the virus' replication if you are taken by surprise by SARS/CoV-2 until reinforcements arrive.
Plus, reinforcements are likely to follow!
Multiple studies have shown that the immune system has been training foot soldiers in addition to creating antibodies and factories that can create them (plasma cell factories) and training better archers (antibodies). These foot soldiers are known as memory B cells or memory T cells. They primarily serve as a surveillance system and look for other infected cells with SARS-CoV-2.
Ellebedy states that they are constantly on the lookout for SARS-CoV-2 in cells. It's almost like walking through the neighborhood house by house and checking that everything is clean.
Although they cannot prevent infection from occurring initially, these foot soldiers can stop it from happening quickly, according to Jennifer Gommerman, an immunologist at the University of Toronto. "Because of the vaccine-generated memory' from the SARS-2 spike protein, you get an extremely rapid cellular immune response."
Okay. Now we have all the information needed to understand the COVID vaccine's effects on immune durability.
Six months after the shots, antibodies in the blood had fallen to their expected level. They are also less effective against the Delta variant. Gommerman states, "Together that implies there are more symptoms infections as we move further out from the vaccine rollout."
These infections are more likely to be mild or moderate in people who have been vaccinated. This is because their immune system doesn't start from scratch. It's actually the reverse. It has been training cells to make antibodies and other proteins for many months.
Gommerman states that "you still have all the immunity in your body that will then tell you, 'OK. We've had an attack and it's time for us to restore cellular immunity and deal with this threat.' You have cells that are capable of doing that quickly because you've been vaccinated. "
She says that overall you will be less sick if you are vaccinated, and less likely to end-up in the hospital.
Gommerman states, "That's what vaccines were made to do. They teach the immune system how to deal with an invader if it does occur." The vaccines accomplish this feat remarkably well.