Why Our Immune System Might Be Better Than We Think At Fighting COVID-19 | CBC News (2023)

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There is currently a lot of confusion and speculation about immunity to COVID-19.

You may have seen the headlines this week suggesting that the antibodies the immune system makes to fight the coronavirus are rapidly declining after infection, threatening hopes of long-term immunity to the virus.

But the problem is more complicated than it seems and more hopeful.

The Prepress Studio, which has not been peer-reviewed, found that the number of people with detectable antibodies in their blood in England has fallen from 6 per cent of the population at the end of June to just 4.4 per cent in mid-September.

The researchers concluded that there was "decreased immunity in the population" and an "increased risk of reinfection" and that the collaborative study of 365,000 patients clearly showed that detectable antibodies decreased.

But while the study and its dire conclusions made headlines around the world, experts say there is much more to consider before we can definitively say coronavirus antibodies don't last long enough to protect us.

After infection, a drop in antibodies is to be expected

An important factor to note is that it's not uncommon for immunity to wane after infection, said Alyson Kelvin, an assistant professor at Dalhousie University and a virologist at the Canada Center for Vaccination who evaluates Canadian vaccines forVIDO-InterVac-Labornot Saskatoon.

"Just showing that antibodies decrease after an infection doesn't simply mean that we are no longer protected," he said. "Our immune system is more complicated than what is good."

In fact, a drop in detectable antibodies is expected after an infection, and that high levels of antibodies remaining after a disease has passed could actually be a bad thing, Kelvin said.

"Normally we would associate a high level of activated immune response with more than one autoimmune disease in the absence of a threat," he said.

"So what we want to see is that some of knowing that our bodies are in control goes away after we've eliminated the virus."

  • Scientists are finding signs of waning antibody immunity to COVID-19 in England over time

The other important factor is that the immune system can actually remember how to make new antibodies when needed to fight future infections by storing types of protective white blood cells in the body called B cells.

(Video) Coronavirus: Immunity explained - BBC News

Kelvin said just because there are no detectable antibodies in the blood doesn't mean we don't have reserves of these immune memory cells stored elsewhere in our body, such as in our bone marrow.

"Typically, memory B cells are hiding there, waiting for further exposure," Kelvin said. "Because these antibodies don't circulate when you're not exposed, you need to store them for when you need them."

Conflicting studies create confusion

another study,published this week in the journal Scienceand peer review, confusion over immunity to coronavirus may have increased.

He studied antibody responses in plasma samples from more than 30,000 COVID-19 patients at Mount Sinai Health System in New York City between March and October.

It came to a very different conclusion from the previous study: that more than 90 percent of patients produced moderate to high levels of antibodies, strong enough to neutralize the virus and lasting for many months after infection.

CLOCK | Antibodies to COVID-19 can wear off quickly, the study says:

Why Our Immune System Might Be Better Than We Think At Fighting COVID-19 | CBC News (1)

COVID-19 antibodies can disappear quickly, according to a new study

2 years ago

Length of time3:33

(Video) How important is the immune system in protecting against Covid-19? | COVID-19 Special
A new British study has found antibodies to COVID-19 can quickly disappear from people who have had the virus, making herd immunity unlikely without a vaccine, experts say.

One difference between the two studies is that the preprint studied patients ranging from asymptomatic to severe, while the published study focused on inpatients, who were mainly symptomatic.

"There seems to be a kind of split that milder cases don't have this noticeable increase in antibody responses for long periods of time after infection," Kelvin said. "That might be more obvious in people with a more severe infection."

The researchers in the New York study concluded that the antibodies they found were likely produced by "long-lived plasma cells in the bone marrow," supporting the notion that latent immune-memory B cells may be hiding there.

  • SECOND OPINION What the level of immunity to COVID-19 in Canada could mean for the vaccine search

"This study suggests that most people infected with SARS-CoV-2 [the coronavirus that causes COVID-19] produce protective antibodies that are likely to protect against reinfection," Kelvin said.

"This would support the idea that we will be able to produce a vaccine that is safe and results in a protective immune response."

How our immune system reacts to the coronavirus

After exposure to a virus, either through an infection or a vaccine, the body goes through what's called an "expansion phase," during which these memory immune cells produce antibodies in response, something Kelvin likens to climbing a mountain.

Once the body thinks it's cleared the infection and reached the top of the mountain, these antibodies begin to wane during what's known as the "contraction phase," the beginning of the descent down the mountain.

(Video) The Immune System | Preserving Disease Resistance After a Transplant

When you reach the bottom of the mountain, the body goes into a "memory phase" where the most potent antibodies are stored until the next exposure, e.g. B. the experience of maybe climbing the mountain better next time.

  • Virus antibodies fade quickly, but that doesn't mean the protection is gone

It is believed that the B cells are not detectable in the bloodstream at this point, but are entering immune reservoirs in the body such as the bone marrow, meaning researchers could miss them if they only focus on the blood

"We don't yet know what amount of these antibodies is actually needed to prevent infection," said Dr. Lynora Saxinger, an infectious disease specialist and associate professor of microbiology and immunology at the University of Alberta.

"But there are many examples of low antibody levels that rise rapidly upon re-exposure to an infectious agent because memory B cells release antibodies upon re-exposure."

Why Our Immune System Might Be Better Than We Think At Fighting COVID-19 | CBC News (2)

Another tool our body uses to fight infection are T-cells, another type of white blood cell stored in the body that can also attack the virus the next time it encounters it, but are adetached arm of the immune system.

A recent article published in Cell magazinediscovered that a balance of T-cells and B-cells produced in the body could lead to a better outcome after coronavirus infection, and Kelvin said a better understanding of T-cell immunity could help vaccine development .

On a positive note, memory B cells, which can protect against future infection, have already been demonstrated in both symptomatic and asymptomatic COVID-19 patients, as mentioned inanother study published in the journal Naturethis week.

  • Asymptomatic COVID-19 results dim 'herd immunity' and 'immunity passports' hopes

Kelvin said that COVID-19 patients who develop serious illness or die after being infected with the virus may have a reduced ability to produce antibodies because they maytargeting and destroying these B cells.

"These results would support the idea that 'herd immunity' through natural infection does not lead to long-lasting immunity," he said. "Which, in turn, puts our vulnerable populations at risk of death."

Other coronaviruses such as SARS and MERS could also provide clues as to how long dormant antibodies are waiting to protect us from infections in the future.

(Video) How COVID-19 Turns Your Immune System Against You

"In both SARS and MERS, years after antibodies were undetectable, immune memory cells primed for specific responses to both viruses could still be found in recovered patients," said Dr. David Naylor, Co-Chairman of the US Federal Government Health.Immunity Working Group.

"Conclusion: Due to the millions of infected people, the duration of the epidemic and the still very low proportion of reinfections, it seems very likely that there will be a fairly long-lasting immunity to SARS-CoV-2 after an initial infection. "

Vaccines are the surest way to achieve immunity

It's important to note that research showing a decline in antibodies over time doesn't necessarily mean we're less likely to be able to develop safe and effective vaccines in the months to come.

"There is still a lot to learn about the durability of immunity," Naylor said.

No one expects any of the vaccine candidates to offer "unlimited immunity," and they may seem more like an annual flu shot, he said.

"The immediate question is whether the vaccines will achieve and maintain sufficient general immunity to keep the spread in check for us to get on with our lives."

Why Our Immune System Might Be Better Than We Think At Fighting COVID-19 | CBC News (3)

Separately, Kelvin says immunity gained from vaccines is safer than that from rampant infections, a concept also known as herd immunity.

"More work is needed to understand how long immunity lasts," he said, adding that while a vaccine may also not provide long-lasting protection, it does not carry the same risk of death that COVID-19 patients face are.

"So a safe and effective vaccine would be the best way to control outbreaks."

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(Video) Immunity to all forms of the coronavirus may be closer than we thought | COVID-19 Special


Does immune system help fight COVID? ›

Your innate immune system is the first line of defense against viruses like COVID, taking minutes to hours to kick in.

Why do I have such a strong immune response to COVID vaccine? ›

It is normal to have a stronger reaction after the second dose because that's when your immune system really kicks into gear. That big immune response is what causes the stronger reaction. It's called a boosting phenomenon, and it builds an even greater ability to defeat COVID-19.

Why are we not immune to COVID? ›

It's possible that it's not a mutation in one gene, but a combination of mutations in multiple genes, that render a small number of people immune to COVID. Targeting multiple genes without causing any unwanted side-effects can be tricky and would make it much harder to harness this knowledge for anti-COVID drugs.

What are the benefits of a good immune system? ›

Our immune system, a network of intricate stages and pathways in the body, protects us against these harmful microbes as well as certain diseases. It recognizes foreign invaders like bacteria, viruses, and parasites and takes immediate action.

Is your immune system stronger after COVID? ›

A new study finds that COVID-19 can trigger stronger inflammatory responses in males, resulting in changes to their functional immunity long after recovery.

How can I help my immune system fight viruses? ›

6 Ways to Boost Your Immune System
  1. Stay up-to-date on recommended vaccines. ...
  2. Maintain a healthy diet. ...
  3. Exercise regularly. ...
  4. Hydrate, hydrate, hydrate. ...
  5. Get plenty of sleep. ...
  6. Minimize stress. ...
  7. One last word on supplements.
Oct 21, 2022

Is it possible to be immune to COVID? ›

Research expands. Such findings have spurred the study of people who appear to have stayed free of COVID-19 despite high risks, such as repeated exposures and weak immune systems.

Can people with weak immune systems get vaccinated? ›

It is important that you are vaccinated against COVID-19 if you have a weak immune system (immunosuppressed or immunocompromised). Having a weak immune system puts you at higher risk of serious illness if you get COVID-19. Getting vaccinated will give you some protection against this.

What are signs of strong immune system? ›

There are many signs that your immune system is thriving, and these are four tell-tale signs you're on the right track.
  • You feel alert. It's okay to feel tired every now and then. ...
  • You sleep well. ...
  • You don't feel sick all the time. ...
  • You regulate your emotions well.
Nov 8, 2022

Will COVID ever go away? ›

Since it first appeared in Asia, scientists have speculated that SARS-CoV-2, the virus that causes COVID-19 (coronavirus disease 2019), will not disappear. Similar to the seasonal influenza virus, it is expected to mutate over time—this has already become apparent as new “variants” of the virus have appeared.

What percentage of people have not had COVID? ›

Serologic testing of US adults finds that nearly 42% have SARS-CoV-2 antibodies indicating previous infection, but about 44% of them said they never had COVID-19, according to a study published today in Morbidity and Mortality Weekly Report.

Is your immune system weak after COVID? ›

The significance of these findings isn't clear, and longer-term studies considering the impact of underlying health conditions on immune function will be needed. But for most people, there's no evidence to suggest immune damage following a COVID infection.

What weakens the immune system? ›

Also, infections, such as the flu virus, mono (mononucleosis), and measles, can weaken the immune system for a short time. Your immune system can also be weakened by smoking, alcohol, and poor nutrition.

What foods build your immune system? ›

10 foods to boost your immune system
  • Berries. With a wide variety to choose from, you can't go wrong adding these little nutrient packed sweet treats to your regular diet. ...
  • Fish oil. ...
  • Leafy greens. ...
  • Nuts and seeds. ...
  • Spices. ...
  • Citrus fruits. ...
  • Poultry. ...
  • Brightly colored vegetables.
Jul 5, 2022

Can you get COVID 3 times? ›

Since it's been estimated that over 80% of Americans have been infected with COVID-19 at least once, concern about reinfection is valid. Indeed, a person can get COVID-19 once, twice, three times or more.

What cells fight COVID? ›

T cells coordinate the immune system's response and kill cells that have been infected by the SARS-CoV-2 virus.

Does getting sick build up your immune system? ›

A child exposed to colds and viruses earlier in life will develop a stronger immune system and is less likely to become sick in his or her later years. “Immunity is immunity,” explains Dr. Jordan S. Orange, chief of immunology, allergy and rheumatology at Texas Children's Hospital.

Is there a cure for the immune system? ›

Treatment to reinstitute the immune system

Stem cell transplantation offers a permanent cure for several forms of life-threatening immunodeficiency. Normal stem cells are transferred to the person with immunodeficiency, which results in a typically functioning immune system.

Which fruit increase white blood cells? ›

Fruits rich in vitamin C include guava, strawberries, papaya, kiwi, citrus, and cantaloupe. Beta-carotene also helps to boost infection-fighting cells & T-cells production and boosts the immune system to increase white blood cells count.

What kills viruses naturally? ›

Using Vitamins and Minerals to Fight Viruses and Support Immunity
  • Vitamin D: Vitamin D, commonly known for its role in bone health, also helps make proteins that kill viruses and bacteria, especially in the respiratory tract. ...
  • Vitamin C: ...
  • Zinc: ...
  • Polyphenols: ...
  • Potassium: ...
  • Probiotics: ...
  • Supplement Wisely.

Why do some people never get sick? ›

Why Some People Evade Colds And Others Don't People who have built up immunity to common viruses are less likely to get sick. But researchers say it's also possible some people are genetically less susceptible to catching a common cold.

How long do COVID antibodies last? ›

Share on Pinterest Research shows that the antibodies that develop from COVID-19 remain in the body for at least 8 months. Immunity can occur naturally after developing COVID-19, from getting the COVID-19 vaccination, or from a combination of both.

How do you fight off Covid? ›

To care for yourself, follow these steps:
  1. Keep a daily routine, such as taking a shower and getting dressed.
  2. Take breaks from COVID-19 news and social media.
  3. Eat healthy meals and drink plenty of fluids.
  4. Stay physically active.
  5. Get plenty of sleep.
  6. Avoid use of drugs, tobacco and alcohol.

Can a vaccine overwhelm the immune system? ›

Vaccines do not overwhelm or weaken a child's immune system. Instead, they make it stronger by providing protection against diseases. Even combination vaccines, which protect against multiple diseases, are easy for your child's immune system to handle.

Is the Moderna booster better than the Pfizer? ›

Pfizer: Is There a “Best” mRNA Vaccine? Both of the mRNA vaccines available in the US are highly effective against severe COVID-19, but recent studies suggest that Moderna's elicits a stronger immune response and might be better at preventing breakthrough infections.

Why can't people who are immunocompromised get vaccines? ›

People who are immunocompromised have an increased risk of morbidity and mortality from many vaccine-preventable diseases.

How do you fight off COVID fast? ›

To care for yourself, follow these steps:
  1. Keep a daily routine, such as taking a shower and getting dressed.
  2. Take breaks from COVID-19 news and social media.
  3. Eat healthy meals and drink plenty of fluids.
  4. Stay physically active.
  5. Get plenty of sleep.
  6. Avoid use of drugs, tobacco and alcohol.

What are signs that your immune system is fighting a virus? ›

Making Sense of Your Flu Symptoms
  • Runny Nose/Nasal Congestion—A runny nose helps wash germs from the nose and sinuses. ...
  • Coughing and Sneezing—Within a few days of a viral infection, the fluid from a runny nose may change color from clear to yellow to green. ...
  • Fever—Fevers fight influenza viruses.

Can you get COVID with a suppressed immune system? ›

Some people who are immunocompromised (have a weakened immune system) are more likely to get sick with COVID-19 or be sick for a longer period.


1. How about getting vaccinated again against coronavirus? | COVID-19 Special
(DW News)
2. How COVID-19 affects your immune system
(Scripps News)
3. Natural Immunity: How your body fights against COVID-19
4. Update 161: COVID-19 Repeated Infections: The Why and What You Can Do
(MedCram - Medical Lectures Explained CLEARLY)
5. How To Boost Your Immune System Against Coronavirus | TODAY
6. Studies show kids' rapid immune system helps them fight off COVID-19


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