As more people receive the novel coronavirus (COVID-19) vaccine, myths are being dispersed on social media. UC Davis Health experts dispell myths and give you the facts about the COVID-19 vaccine.

Get more answers to your COVID-19 vaccine questions


UC Davis Health nurse getting COVID-19 vaccine

Fact: COVID-19 vaccines are safe.

Both the Moderna and Pfizer vaccines have been very well studied and underwent full reviews by experts. Nearly 44,000 people enrolled in the randomized Pfizer clinical trial, including 225 at UC Davis Health. The results were carefully reviewed, and both vaccines were scientifically proven to be very safe.

The U.S. Food and Drug Administration (FDA) and other experts reviewed data from the clinical trials quicker than normal by looking at data as it came in. In most cases, they wait until the trials are complete. They used the same safety and efficacy standards as always. No safety protocols were changed or skipped.


Woman being vaccinated for COVID-19

Fact: COVID-19 vaccines will not give you novel coronavirus.

There's no way to get COVID-19 from the vaccine. None of the FDA-authorized vaccines, or vaccines currently in development in the U.S., use a live virus.

The Pfizer and Moderna vaccines use messenger ribonucleic acid (mRNA), which carries instructions to your body about how to build a protein. In this case, it’s telling your body to make the spike protein that’s on the novel coronavirus. As a result, your immune system remembers the protein and is ready to attack and eliminate the real SARS-CoV-2 virus.


test tube showing positive for COVID-19

Fact: You cannot test positive because of the COVID-19 vaccine.

There's no part of the novel coronavirus in either the Pfizer or Moderna vaccines. Therefore, you can't test positive on a PCR or antigen test (the two methods that test for current COVID-19 infection). You will, however, test positive for COVID-19 antibodies because your body will have built them up as part of your immune response, which is a good thing.


research using test tubes

Myth: COVID-19 vaccines were developed too quickly.

The COVID-19 vaccines were made at record speed, thanks to the worldwide effort. Along with the constant review by regulatory experts which sped up the process, there were two other reasons for the speed. The first was urgency. COVID-19 vaccine manufacturers and the scientific community dropped everything to develop a vaccine.

The second reason for a speedier process was that the innovative mRNA approach was already in development. Researchers already created a process for getting the mRNA into the body as part of trials for cancer efforts and other vaccines. What they needed to learn was the genomic sequence of the novel coronavirus.


baby being held

Fact: COVID-19 vaccines do not cause infertility.

There's no evidence that COVID-19 vaccines have any effect on fertility. The Vaccines and Related Biological Products Advisory Committee (VRPAC) briefing for both Pfizer and Moderna detail the findings from the clinical trials about effectiveness, safety and side effects. There are no reports of any impact on fertility. You can read the 50-plus page briefings from VRBPAC to the FDA.


box of COVID-19 vaccines

Myth: There's a government mandate to get a COVID-19 vaccine.

UC Davis Health experts and health officials at every level urge everyone to get a COVID-19 vaccine. The more people who are vaccinated, the faster everyone can return to normal. However, there is currently no government mandate to get the vaccine. It’s possible that might change later. Many businesses and schools may decide to require COVID-19 vaccines, similar to what's required for the flu and other diseases.


woman sitting with a coffee cup

Fact: One or two days of side effects after the COVID-19 vaccine means it's working.

Some inflammation or soreness at the injection site, as well as minor side effects after getting a COVID-19 vaccine is normal. Everone will have a slightly different reaction. Chills, fatigue or body aches for a day or two are signs that your body is building its immune response.


UC Davis Health employee getting COVID-19 vaccine

Myth: Natural immunity is safer than immunity from a COVID-19 vaccine.

For many diseases, immunity acquired naturally often lasts longer than immunity from a vaccine. But that means you have to suffer – and survive – the disease.

With COVID-19, the natural immune response after a mild case appears to be short lived and is much shorter than what's expected from the coronavirus vaccine. If we were to wait until we reach natural immunity, society would be shut down much longer. Millions of people would likely die and many millions more would suffer.


stethescope on papers

Fact: There's no microchip or tracking device of any kind in either COVID-19 vaccine.

This debunked myth morphed into a conspiracy theory after Bill Gates suggested creating a digital certificate of vaccine records. Gates, in fact, has been the top subject of COVID-19 misinformation since early in the pandemic, according to media analysis company Zignal Labs and CNBC.