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Coronavirus Overview

The COVID-19 vaccine is safe and effective

How do we know this? Because our experts have dedicated their lives to studying how infectious diseases and vaccines work. While the COVID-19 vaccines are new, the technology they use has been studied and refined for decades.

Two types of vaccines

There are two types of COVID-19 vaccines currently approved by the FDA that rely on mRNA technology: Pfizer, which has full FDA approval; and Moderna, which has emergency use authorization (EUA). Scroll below for more information on how this new technology works and why it's safe. The Johnson & Johnson vaccine uses a technology called viral vector. Read more from our experts about how viral vector vaccines work.

Here's how the mRNA vaccine protects you

SARS-COV-2

SARS-COV-2 is the strain of coronavirus that causes COVID-19. It's known as a spike protein. Spikes allow a ribonucleic acid (RNA) strand to enter the body, reproduce and kill healthy cells.

When the virus enters the body

When a virus enters the body, your body's immune system creates antibodies to fight the virus. Since COVID-19 is a novel virus, our body's immune system has not encountered this virus before and isn't prepared to fight.

How the vaccine protects you

The vaccine contains messenger RNA made with the genetic code of spike proteins. When you're injected with the vaccine, this messenger RNA enters your cells and produces a protein to stimulate an immune response, similar to COVID-19.

Now if you encounter the real virus, your body will recognize COVID-19 and is trained to fight it.

Learn more about the science, side effects and developments in the COVID-19 vaccine

What our doctors get asked the most

We asked primary care providers in The Ohio State University Wexner Medical Center’s Department of Family and Community Medicine to share what they’re asked most when it comes to the COVID-19 vaccine.

How quickly does the COVID-19 vaccine work?

Here's what we know about how quickly, and how much, protection you'll get in the weeks following your vaccination. Plus, learn why wearing a mask is still recommended no matter how much time has passed since getting the vaccine.

How quickly am I protected?

What to know about mRNA: the science behind the vaccine

An infectious disease specialist breaks down how mRNA vaccine technology works and why scientists and medical experts are confident in its safety.

COVID-19 Vaccine Side Effects

Frequently asked questions

Are the vaccines safe?

The vaccine is deemed to be safe based upon a rigorous evaluation of currently available scientific evidence. If the available scientific evidence changes or if new information becomes available, the authorization for its use can be adapted.

The Pfizer vaccine study enrolled 43,538 participants, with 42% having diverse ethnic backgrounds. No serious safety concerns were observed. The only Grade 3 (severe) adverse events greater than or equal to 2% in frequency were fatigue (3.8%) and headache (2%).

The Moderna vaccine study enrolled 30,000 participants, with 37% having diverse backgrounds. No serious safety concerns were observed. The majority of adverse events were mild or moderate in severity. Grade 3 (severe) events included injection site pain (2.7%), fatigue (9.7%), muscle pain or soreness (8.9%), joint pain (5.2%), headache (4.5%), pain (4.1%) and redness at the injection site (2%).

All vaccine trials have scheduled monitoring reviews, typically by an independent group known as a Data and Safety Monitoring Board, which routinely assesses safety or can be convened quickly to review any unanticipated adverse events.
Did the COVID-19 vaccine go through a clinical trial?

Yes. Operation Warp Speed was an effort to develop vaccines and therapeutics quicker than would normally be possible by running the three phases of these clinical trials in an accelerated time frame. They also start manufacturing on a large scale before the studies are done, so that vaccines will be ready to be administered as soon as possible once they're approved, having been declared effective and safe. All of the vaccines go through the standard steps, but in a much faster process made possible, in part, by the large number of patients available to participate in each trial.

This six-minute video (https://youtu.be/Z06JQhyZLUI) and the illustration below further explain these points.

How many people received the vaccine during the trials?

The Pfizer vaccine study enrolled 43,538 participants. The Moderna vaccine study enrolled 30,000 participants.

Have more questions? We have more answers. Read all COVID-19 vaccine frequently asked questions.

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How the COVID-19 Vaccine Works

The science behind how the vaccine protects you and your loved ones.