Friday, December 11, 2020

COVID vaccines 101


COVID vaccines 101:

AKA: Why YOU should get a COVID vaccine

As everyone has heard by now, Rhode Island is beginning to distribute COVID vaccinations to first responders, emergency department staff and home healthcare workers in the next few weeks. Many people have questions and concerns about the vaccinations, particularly regarding the safety and effectiveness of the vaccines. This blog series is intended to answer common questions and give general information about the vaccines. 

First: why get a vaccine at all? 

The short answer: this is a big part of getting the country back to normal. The vaccine will boost your immune system and allow it to recognize COVID. This will help protect us and our brothers and sisters on the front lines and help to generate herd immunity . It will help prevent severe illness and likely help prevent transmission. Until they are used in the “real world” the actual effectiveness will not be known. What IS known is the overall safety of the vaccines and the ability of the vaccines to generate antibodies. 

Let’s get started:

What exactly does a vaccine do?

A vaccine introduces something to your body to prepare it to recognize illness-causing virus or toxin in the future. In some cases, that “something” is a live virus that has been altered to be inactive. In others, it is a protein that is found in the virus or toxin. Usually this is done by directly injecting the protein, toxin or virus into your body. By introducing this substance to your body, your immune system can “learn” to recognize it and rapidly make antibodies if you are exposed to it in the future.

The two COVID vaccines receiving the most attention (Pfizer and Moderna) introduce a protein unique to COVID in a relatively new way. The way the COVID vaccines work is by giving your body a set of “instructions” for making a harmless COVID protein called a “spike” protein. Your cells will use the mRNA (which acts as a set of instructions) to make this harmless spike protein. Your immune system then recognizes the spike protein as “foreign” and produces antibodies to it. The cell then destroys the mRNA.

COVID has this protein on its surface and it uses it to get into our cells. If COVID can’t get into our cells, it can’t replicate… So the spike protein is a great choice for vaccine target. Once your body produces antibodies to the spike protein, those antibodies will “stick” to the spike protein, making it easy for your immune system to recognize and destroy the virus particles and inactivating the spike protein so it can’t get into your cells.

Fun fact: The mRNA used in the vaccines does NOT enter the cell nucleus, where our DNA is kept. It's very complicated why… but things can't just “go into” the cell nucleus. The mRNA does not "become part of our DNA." The cell destroys it once it reads the instructions to produce the spike protein. So, no superpowers yet!

Are the vaccines safe? Do they work? How do we know?

First, let’s get one thing out there: NO drug or vaccine is 100% safe. All drugs and vaccines have side effects. The goal is to determine what the risks are, compare those risks to the risks of the disease, and show there is a clear benefit. Some drugs have common, severe side effects and even fatal complications (think chemotherapy agents), but since the disease carries a high degree of risk (cancer), they still might be approved for use. To contrast that, some drug have known, rare complications (such as a risk of bleeding or ulcers with ibuprofen or aspirin) but those complications are so rare that those drugs are used widely.

Vaccines are given to HEALTHY people so the bar for safety is set much higher than a drug to cure sick people.

Prior to authorization for use, companies are required to release ALL data and information from vaccine trials, including animal studies and all 3 phases of trial, much more than is available to the general  public.  It’s thousands of pages of information. It is all reviewed prior to FDA approval for use.

So far there is data from about 20,000 people immunized  (and 20,000 who received a fake "placebo" shot) in the Pfizer trial and more than 15,000 (and 15,000 + who received a placebo) from the Moderna trial. With so many people vaccination, most if not all of the common side effects will be known. There is a chance a VERY rare side effect (like, for instance the 1 in a million chance of a condition called Guillain Barre syndrome that we see with seasonal flu vaccine) will not be seen until mass vaccinations occur. But it’s important to remember that those very rare side effects are just that- very, very rare and are present in vaccinations we use today. There is nothing in all of medicine that doesn’t have some amount of side effects.

It is important to remember, not all things that happen after a vaccination are due to the vaccine. Think about a nursing home. A number of people in a nursing home die every month. Once nursing homes are vaccinated, a number of residents will still die every month. Some people will get a COVID vaccine and then die in an MVC, or have a heart attack. Don’t be fooled into thinking that every sensational news report of post-vaccination events is directly related to the vaccine. they WORK?!

It's very clear from the data that the vaccine is safe... What about effectiveness? This is probably the trickiest thing to figure out in a trial... It's hard to predict how well the vaccine will really perform in real life, especially when and if people stop wearing masks/etc. Still, the data in terms of effectiveness is pretty amazing. It seems to hugely decrease the likelihood of severe infection and probably prevents a lot of primary infection as well. If that effectiveness data holds up you will be less likely to get COVID and MUCH less likely to die/end up really sick if you do get it.

This image shows the incidence of COVID infections
with vaccination (flat line) and with placebo- see the difference??

How did they develop the vaccines so fast? Doesn’t that mean they cut corners and the vaccine has not been proven to be safe?

There's a lot of misconceptions, particularly regarding the "rushed" development of this vaccine. As opposed to reassuring people, the unfortunately named “Operation Warp Speed” seems to have given the general public the impression that the vaccines were “rushed” and are therefore unsafe.

Typically, a vaccine takes 10-15 years from start to widespread manufacturing and development. You generally have to finish each stage, process data, prove efficacy and safety and THEN you can try to get funding to move to the next stage. There are several reasons vaccine development happened so fast with COVID. 

First, there was already significant progress on vaccines for coronaviruses, including the mRNA technology, particularly after the SARS and MERS outbreaks occurred. A major reason these vaccines did not make it all the way to production involves simple economics. Even though those diseases were severe, the outbreaks associated with them were brief and contained. Once those outbreaks ended, the funding also dried up to further develop the vaccines. Normal coronaviruses such as those that cause the common cold are widespread and common but aren't generally severe enough to make a vaccine worthwhile. COVID is a perfect storm of a severe, extremely widespread coronavirus with a huge need (and eventually a huge market, because obviously these companies need to be profitable).

Second, the government paved the way by 1) financing with over $10 billion 2) accelerating the approval process/paperwork/etc and  3) giving the go-ahead and funding to START vaccine production DURING the phase 1 trial. So these vaccines were in production before the data was back- a HUGE risk that no company would ever accept under normal circumstances. There was a big chance one if the vaccines would have failed trials and all that work and money would have been lost. The "operation warp speed" really just cut red tape, provided funding and accelerated production.

Fun fact: COVID is NOT the first vaccine to be developed quickly. The mumps vaccine took only 4 years to develop, using science developed during WWII. The 2009 H1N1 (the original “swine” flu) took only just over 5 months.

What about all these side effects I keep hearing about?

When a vaccine or drug is developed, it is required to keep careful track of any and all side effects and events that happen after administration of the drug. ALL events are recorded, whether related or not. If you’ve ever actually read the inserts that come with medications, you know that just about any side effect can be found in the list. Common side effects are just that- the most commonly seen events after vaccination. The Pfizer study found the most common side effects were reactions at the site of the injection, fatigue, headaches, muscle pain, chills joint pain and fever. These side effects were more common after the second dose. Side effects like these are expected when your immune system mounts a response- just like when you really get sick. There were no overall safety concerns raised during the trials.

“Serious reported events” are more closely investigated, and sometimes a trial is even halted until it can be determined whether the event was related to the vaccine. About 1% of people in the Pfizer trial reported “serious adverse events” such as heart attacks; this rate is what was expected in the general population. What that means is, these events most likely had nothing at all to do with the vaccine- they were simply the usual ailments that are expected to happen in a population of humans. 

Fun fact: Among the “reported adverse events” were a shoulder injury in the injection group and a stroke and a heart attack that occurred in the placebo group. 

How long will the vaccine work for?

It's too early to tell how long it will work. It will take large scale distribution of the vaccine to really test how much and how long it will prevent COVID transmission. That's how all vaccines work, really. The trails prove safety and efficacy (how well it works) but they aren't truly "real life." In mice the Pfizer vaccine gave protection for 13 weeks, which could translate to years in humans. The good news is, even some protection over a limited amount of time will likely make a huge impact because so many people are at risk and it spreads so easily.

Fun fact: Many vaccines require a repeat dose or a “booster”, both for waning immunity and for changes in the pathogens over time. Influenza is a great example with the whole “yearly flu shot” thing, but even diseases such as tetanus and whooping cough do require a periodic “booster.”

To wrap this up: if you want further convincing, talk to your peers and colleagues who are going to get the vaccine. I am getting one as soon as possible, and I’ll be giving them to my daughters, 92 y/o grandmother and dad as soon as they are available. 

Thank you! 

Hang in there and be safe!

-The EMS Division

Disclaimer: The above is intended to answer commonly encountered questions in layperson terms, using the most up to date information at time of writing. Do your homework, look for reputable information and ask questions. We will periodically update this as more information becomes available. 


Links for further reading:

FDA “vaccine development 101” 

CNBC video on the basics of vaccine development, clinical trials and the approval process

Operation Warp Speed Info Sheet:

Full FDA briefing on Pfizer trial data:

Washington Post "What you need to know about COVID vaccines:"

1 comment:

  1. I shared this article and somehow my email came up in the comment as section. This will be the only comment that I will make on this article. Any further comments are not mine.