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Covid Vaccine FAQ Part 4: Vaccine Efficacy

Updated: Jul 31, 2021

Picture of Covid virus

This is Part 4 of a 5 part series. Part 1 covers foundational information about how the vaccines work and common questions / myths related to vaccine technology. Part 2 covers questions related to vaccine ingredients and potential toxicity. Part 3 covers questions regarding the safety of the Covid vaccines.

In this section I will cover questions related to vaccine efficacy:

If you would like to navigate directly to the other posts you can click below.


Vaccine Efficacy

These new vaccines appear to be very effective at this point in time. How long will they be effective? We don't know, and will depend in part on how many new variants evolve and what they are like. Before I launch into the Q &A, I do want to take a minute to mention that the media reports on the efficacy of each of the vaccines was based on a type of statistical analysis called "relative risk". There is a different way to assess how effective something is, and that is "actual risk". When looking at "actual risk" the J&J vaccine is actually the most effective (based on the current data, which will change over time). That is not a reason to get J&J over the others, but it is good to remember that there is often more to the story than statistics reported in the media.

So, without further ado, let's jump straight into the FAQ.

Q: How long does the vaccine last? Why should I bother getting the vaccine if it only lasts three months?

A: We don't know how long immunity from the vaccine lasts. We know immunity lasts for one more month after each month has passed. That said, we know at this point that immunity from the vaccines lasts at least 10 months (the earliest date that the first volunteers got the vaccine). Antibodies induced by the vaccines show no signs of fading, so it is likely that they will last for a long time, providing solid immunity to the original virus and the first few variants. Will immunity be permanent like it is with some vaccines? It is possible. Time will tell.

Why should you bother? People are dying and becoming disabled (by the thousands) right now. Also, the more people that get infected, the more chances the virus has to mutate. The faster we can reach herd immunity, the faster we can slow down or stop mutation of the virus, thus reducing the chances that we will end up with a new variant that the vaccines do not work against.

Q: What about break-through infections? Can't you still get Covid after you have been vaccinated?

A: Break through infections are real, as are second infections after having Covid. I have not been able to find solid statistics on second Covid infections after an initial infection, so I don't know if one is more common than the other. In mid April 2021 there were 95 million people vaccinated and 9,245 of those people were hospitalized for Covid after being vaccinated. That is 0.01%. The vaccines were projected to be 90% effective- this indicates that they are closer to 99% effective. So, it is possible to become infected with Covid after getting vaccinated, but it is incredibly rare.

Picture of lady coughing

Q: Isn't having immunity from getting Covid better protection than getting the vaccine?

A: Actually, no. The opposite is true. Immunity from the vaccine is far superior to immunity from infection with Covid.

Early data is finding that the type of immune response we have to Covid infection does not create a strong, lasting antibody response. Infection with Covid seems to activate a part of the immune system that actually blocks the formation of memory cell lines, which greatly lowers long term immunity. These studies found a surprisingly rapid deterioration of immune cell lines needed for immunity following natural infection. This was not universal. Some people do seem to acquire stable immunity (at least several months of immunity) after having Covid, but these studies indicate that it is not a guarantee, and that we should expect natural immunity to fade unusually quickly. Because of the loss of antibodies generated during infection, it is unlikely that we will be able to achieve herd immunity through natural infection. (References 1-4)

Autoimmune risk

Infection with Covid, particularly if the symptoms are severe or it becomes chronic, can increase the risk of developing a new autoimmune disease. These same studies are finding more autoimmunity in people who recover from having severe Covid infections.

The vaccine (especially the mRNA vaccine) appears to produce a strong and lasting antibody response (it does not trigger the part of the immune system that blocks this), and it appears to lower the risk of developing autoimmune disease (certainly compared to infection with Covid). For all of these reasons, the immunity from vaccines is superior to immunity from natural infection. (Reference 2)

Risk of Long Term Covid Syndrome

Post Covid Syndrome is a multi system, chronic inflammatory disorder that develops in around 10% of people who are infected with Covid. Considering the astronomical number of people infected, this has left a huge number of people (36 million or more) suffering from this mysterious, debilitating illness. It can occur even in young people, even following mild or asymptomatic infections. (I have seen several college students with this, after having virtually no symptoms with the initial Covid infection). It can do permanent damage to vital organs such as the heart, lungs, kidneys, and brain. It causes weakness, severe fatigue, severe brain fog, heart arrhythmias, shortness of breath and more. Getting the vaccine gives you immunity without running this risk.

Risk of spreading Covid to others

Hoping to become immune to Covid by getting Covid is, in my opinion, horribly irresponsible. If you got Covid before you had a chance to get vaccinated, I am not blaming you- obviously, this was out of your control. If you choose not to get vaccinated because you are OK with getting Covid yourself, please reconsider. If you contract Covid, you are very likely to spread it to others. Covid has an unusually high incubation time (up to two weeks) compared to other viruses such as the flu (two days). It also stays contagious for up to two weeks after symptoms occur. Additionally, it has an unusually high rate of asymptomatic or low-symptom infections. That means lots and lots and lots of opportunities to spread the virus to others. While you might not get terribly sick, one of the people that you spread it to might, or they might give it to someone else who could die from Covid. Getting the vaccine gives you immunity while lowering the transmission rate to nearly zero.

Q: Some people are worried about how variant strains factor in. Are we just going to have to commit to getting a bunch of boosters. If so, is that really so bad?

A: People should be worried about new variant strains. Variants can be more contagious, and more deadly, though they can also be less so. Some variants will be similar enough to the original virus that the vaccines will still work. There is also the possibility that the virus could mutate and get around the current vaccines completely. If that happens, we will be starting all over again. We really, really don't want that to happen. As I stated above, the best way to slow down or stop the mutation of the virus is to reach stable herd immunity. The fewer bodies that get infected, the fewer opportunities the virus has to change.

Regarding boosters: time will tell how long immunity created by the current vaccines lasts. Viruses mutate at different rates. The flu virus mutates so quickly that it is different by the end of a single flu season, thus the need for a yearly flu shot if you want immunity. Other viruses such as measles, mumps and tetanus mutate very slowly. You may not remember, but when you got your childhood vaccinations, you received a booster shot for most of these. Because those viruses don't change much, that second booster is generally enough to give you lifelong immunity. The Covid virus is somewhere between Influenza and Measles. It seems likely to me that boosters for Covid might be necessary, but we will not know the frequency until the current situation plays out.

The only good news about boosters or new vaccines for new variants is that we will be able to make them even faster than we made the current vaccines. All the systems are in place and since the mRNA vaccines are essentially "plug and play", they can be updated very quickly.

Iron man hand

Q: Are vaccines creating a false sense of security without knowing the true efficacy (as in, we all think we're in the clear and can go back to normal, and then SURPRISE it's not as effective as we thought it was)?

A: That depends on a lot of things that are unknown at this point in time. As stated before, with the high number of test subjects in the original studies, along with the millions of doses that have been given, the current efficacy is pretty clear. What we don't know is how long that will last (indicators are good at this point that immunity from the mRNA vaccines will be solid). The other wild card, of course, is new variants. The most likely reason for a surprise loss of protection will be new variants. If we achieve herd immunity, the chance of new variants goes way down.

The best strategy is to get vaccinated, and continue to be cautious. Continue to wear a mask when in indoor public places that are crowded with people you don't know. Continue to maintain social distance in public places as much as you can. Continue with hand washing. Follow CDC guidelines on what is safe/ what is not. We will get the all clear when we reach herd immunity.

Q: How invincible am I once I get the vaccine? Does getting the vaccine guarantee that I will not be able to get OR transmit COVID?

A: No vaccine is 100% effective, and I know this is cliché, but obviously there are no guarantees. The mRNA vaccines by Pfizer and Moderna were initially estimated to be 90% effective against infection. Now that we have vaccinated millions of people we are able to observe how well that plays out in the real world.

Today (May 13, 2021) the CDC announced new data indicating transmission rates are very, very low in vaccinated people (almost zero). This new data shows that vaccinated people are extremely unlikely to become asymptomatic spreaders. Based on this, the CDC released new guidelines for vaccinated people: if you are vaccinated, you are allowed to take off your mask in many situations! Keep in mind that this is true for the original virus and the common variants currently in the US. This could easily change with new variants. (Reference 6).

So, I guess the answer is that you are much safer than you were and much less likely to spread the virus to others. I would not say that anyone is ever truly invincible (show me a system that can't be hacked), but the newest data indicates that the vaccines are making a huge difference, and are moving us in the right direction to get back to normal life.

Q: If I experience symptoms with the first shot, does that mean I already had COVID? A: Not necessarily. Everyone's immune systems are tuned a bit differently. Some of the differences are genetic, but a lot of the differences are based on nutrient status, allergy levels, other infections, and exposure to environmental toxins. There are a LOT of reasons that one person's immune system responds differently than the next person. We accumulate those reasons over the course of our lives and they change from day to day based on a multitude of factors.

Q: Does intensity of symptoms after the vaccine correlate to a stronger immune system?

A: Again, not necessarily. For all the reasons listed above. I would say that a strong, quick response (aches and fever within 24 hours, that also resolves within another 24 hrs) is a sign to celebrate. I would not worry if you don't have these symptoms. If you are not immune compromised (via illness or medication) then your body will make the antibodies.

Thank you for reading. Stay tuned for Part 5!


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