NEW Updates on Covid-19 Vaccine Immunity
Dear Rich Lifer,
Back again with some more updates as vaccine news continues to roll out…
As more and more Americans are becoming vaccinated, many questions are arising about how long protection from the coronavirus lasts.
We are now four months (to the day) into the vaccination process, and thankfully, each day brings new information and additional knowledge about the vaccine itself.
While, unfortunately, there are still many unknowns about the long-term efficacy of the Covid-19 vaccines, there has been a huge increase in data that can help us gain insight into the vaccine.
So today, we will go through some of the most commonly asked questions so that we can all feel safe and secure protecting ourselves from the coronavirus.
How Long Does the Vaccine Protect from Covid-19?
Timothy Brewer, MD, professor of medicine and epidemiology at UCLA, explains that most information we have about vaccine efficacy comes from the Pfizer and the Moderna vaccines because their trials started the soonest. Their data is very promising.
Pfizer announced their vaccine remains at 91% efficacy for trial participants a full six months after the second dose. Additionally, a study posted in The New England Journal of Medicine reported that those who received the Moderna vaccine had robust levels of antibodies in all age groups six months later.
Some people have seen this data and assumed it means protection only lasts for six months, which is incorrect. Scott Hensley, a professor of microbiology at the University of Pennsylvania, points out that “We only have six months of data…Six months from now it’s likely we’ll learn we have one year of protection.”
We have to remember, when we get one of these vaccines, the efficacy doesn’t suddenly wear off overnight. What you will actually experience is a slow decline over time.
The vaccines work by causing your body to produce antibodies and memory cells, which help your body remember the infection and fight against it in the future. As both these cells diminish, you’re not unprotected; you’re just less protected than you may have been initially.
Dr. Brewer notes, “That means you have a very long time before the levels fall far enough to actually be in a range where you could potentially become infected again, or to get serious disease if infected.”
In fact, a recent study showed that people who were naturally infected with COVID-19 maintained antibodies for eight months after becoming ill, and since the vaccine creates more antibodies than natural infection does, it’s safe to assume you would be protected for even longer than that after vaccination.
Protection from any disease does have a lot to do with the virus’s ability to mutate. Dr. Brewer states:
Protection is a function of two parts. So one part is how good and durable the immune response is, and the second part is how much the virus changes. One of the reasons you have to get an influenza shot every year is not because your immunity to that particular influenza virus has waned. Instead, it’s because the influenza virus changes enough, over time, that when you’re exposed the next year it’s a slightly different virus.
This brings us to another pressing question…
What About Emerging Variants?
A few worrisome variants of Covid-19 have emerged, which has left many confused about whether the current vaccines offer protection against them.
Dr. Brewer explains that all three vaccines offer “very good” protection against the B.1.1.7 variant, which originated in the UK.
Additionally, Pfizer trialed vaccinations on 800 people in South Africa, many of whom were exposed to the B.1.351 variant, and none of them caught COVID-19.
The J&J vaccine was also trialed in South Africa and Brazil, where the P.1 variant originated. The trial showed 100% efficacy in preventing serious disease and death, even with exposure to the more dangerous variants.
If even more problematic variants continue to emerge, they could affect the efficacy of our current vaccines. However, Scientific American reports that drug companies are working on developing “booster shots” to attempt to bump up antibody levels to better protect from new variants. Moderna has also begun manufacturing a new vaccine targeted specifically at mutations contained in the B.1.351 variant.
David Topham, a professor of microbiology and immunology at the University of Rochester Medical Center, believes boosters will be needed for a few years “out of an abundance of caution, knowing that immunity does wane in some individuals more than others,”
The good news is that vaccines based on genetic material, such as the Moderna and Pfizer immunizations, are specifically well suited to modifications since scientists can easily swap in new genetic sequences as needed.
Could Vaccines Provide Lifelong Immunity?
Some scientists believe that a certain level of protection could last for years or decades, but it’s too soon to say for sure.
Monica Gandhi, an infectious disease physician and professor of medicine at the University of California, San Francisco, points out a 2020 Nature study that revealed that patients who got SARS (a similar coronavirus to Covid-19) had T cell immunity 17 years later!
A preprint under review at Nature Portfolio Journal shows evidence that memory B cells are produced by the Pfizer vaccine seven weeks after vaccination. Memory B cells are white blood cells that can be stimulated to generate new antibodies decades later.
And what about protection from a natural infection? In other words, if you’ve already had coronavirus do you still need to get vaccinated?
The CDC recommends that everyone still get a vaccine even if you have already been infected with coronavirus. There is evidence that suggests protection via natural infection can be strong but differs from person to person.
A Danish study published in March in The Lancet Medical Journal found that immune response after infection was variable. Some individuals lost antibodies after three months, while others maintained high levels eight months later.
So while we still have much to learn before we can be 100% absolutely certain how long the Covid-19 vaccines will last, the takeaway, for now, is that you will be well protected for at least six months, if not longer.
To a richer life,
The Rich Life Roadmap Team