How do the COVID-19 vaccines work?
mRNA vaccines explained
Three vaccines have been approved for use in the United States – Moderna, Pfizer/BioNTech and Johnson & Johnson. All three vaccines provide immunity to the virus without ever having to be infected by it.
NOTE: As of April 11, the Johnson & Johnson has been paused for evaluation due to the development of blood clots in 6 recipients.
The Moderna and Pfizer/BioNTech vaccines use mRNA technology, and the Johnson & Johnson vaccine uses an adenovirus.
While the COVID-19 virus is new, scientists having been working for decades on mRNA and adenovirus vaccine research. This technology is not new and is extremely well-studied.
All three vaccines underwent a four phase testing process with United States Food and Drug Administration (FDA) that involved thousands of volunteers. The vaccines were approved by the FDA for use at the end of 2020.
To date, more than 100 million people in the US have received at least one vaccine dose.
+ What’s an immune system?
The immune system is a huge network of different cells and proteins in your body. You’ve got things like white blood cells that fight the invading virus or bacteria, communication cells that organize the response, and antibodies that search for and identify the enemy.
When a virus (or bacteria) attacks your body, your immune system attacks back. It is the “natural” defense system that our body has built in.
+ What's a vaccine?
Vaccines prepare your body’s immune system to recognize and fight off germs.
Once your body knows (is taught by vaccines) to recognize a virus and has figured out how to fight it, your body’s natural defenses kick in more quickly and therefore help us not get as sick.
Visit the LA County of Public Health to learn more about how vaccines work.
+ How do vaccines provide immunity?
Vaccines prepare your body’s immune system to recognize and fight off germs. Germs are also known as viruses.
Once a vaccine has taught your body how to recognize and fight a virus, your immune system is able to prevent a disease like COVID-19 so that you don’t become dangerously sick if you are exposed.
+ Can the vaccines make me sick with COVID-19?
NO, the current vaccines don’t include the virus in any form – no live virus, no weakened virus, no dead virus. You just cannot get the disease from the vaccine.
It is easy to be confused about this, because you might feel some side effects for a while after getting the vaccine. In fact, about half of the volunteers who tested these vaccines experienced some side effects: most of these effects were mild and did not require any treatment or change in daily activity and lasted for 1-2 days. What they were feeling was not COVID-19, however, not even a mild case of COVID-19.
+ What happens after the vaccine?
The immunizations take two weeks to become completely effective following your second shot. It's critical to obtain a booster dosage when you're eligible for the best protection.
Although vaccination dramatically decreases your chances of contracting COVID-19, infections can still occur. Continue to protect yourself and others once you've been vaccinated:
Wear a mask that fits and filters well
Stay home when sick
Wash your hands often
Avoid crowded places and spaces with poor air flow
Keep your distance
+ What is scientific research?
"Scientific Research" does not mean that you are being researched on.
Many of us work like scientists all the time. For example, when we meet a new person, we often decide (hypothesize) that the person may be someone we like. Based on our experience (past research results), and then based on future experiences of conversation and support from this person (evidence) we determine if that person is trustworthy enough to be a friend.
In medical science this means that scientists and medical providers are studying the impact of something (an illness, a treatment etc.) on people and deciding if their initial impressions (hypothesis) leads helpful understandings and solutions. They confirm, modify or reject their hypothesis with what they learned and move on to the next step of learning more.
Scientific research in many ways is the same as a growth mind-set, when we allow new information to change and transform our understandings. This is why there are often constant changes and refinements to our understandings.
+ What is mRNA technology?
mRNA vaccines provide human cells with instructions on how to create a piece of the coronavirus “spike” protein. This teaches our cells how to trigger an immune response in our bodies, which helps fight the virus that causes COVID-19. Having immunity to the virus prevents us from becoming sick.
mRNA vaccines are different from standard vaccines because they do not contain a live virus and do not carry a risk of causing disease in the vaccinated person. This is another reason pharmaceutical company were able to produce the vaccine so quickly.
+ What is an Adenovirus?
Adenovirus is a form of Viral vector vaccine. This method uses a modified, harmless version of a different virus (the vector) to deliver important instructions to our cells. The non-threatening virus enters a cell in our body and uses the cell's machinery to produce a harmless piece of the virus that causes COVID-19. This piece is known as a spike protein and it is only found on the surface of the virus that causes COVID-19.
The cell displays the spike protein on its surface, and our immune system recognizes it doesn’t belong there. This triggers an immune response and our bodies begin producing antibodies to fight off what it thinks is an infection.
At the end of the process, our bodies have learned how to protect us against future infection with the virus that causes COVID-19.
+ Will the vaccine give me COVID-19?
The COVID-19 mRNA vaccines do not give you COVID. mRNA and Adenovirus from the vaccine do not affect or alter a person’s DNA.