Testing positive after COVID-19 vaccination: Explained

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Vaccinated people have tested positive for COVID-19. Experts say this does not indicate an issue with the vaccine.

With the COVID-19 vaccination program rolled out nationwide, more and more people are beginning to get the lifesaving inoculations every day.

And while many people expected to get some form of minor reaction (headache, mild fever, etc.), that small risk was worth their ultimate goal: to be protected against COVID-19.

However, recent headlines have grabbed people’s attention — vaccinated individuals have tested positive for COVID-19.

How could this happen? What does this mean about the vaccine? What should we do?

Experts were not surprised

Public health and vaccine experts say there are reasons why some patients who have had their shots are testing positive for the coronavirus.

Vaccines protect against illness
Even once someone has received their shots, they are still susceptible to being exposed to the coronavirus and potentially infected. The vaccines are designed to protect against becoming sick or ill to the point of potential hospitalization. Someone can become infected, but the vaccine protects against becoming symptomatic.

Vaccines take time
Once vaccinated, it takes the body and the immune system time to build its defenses and antibodies against the coronavirus. All vaccines take time — sometimes weeks — to become effective. Someone can become infected with the coronavirus after their shots but before their immunity develops.

Vaccines don’t work backwards
A vaccine does not fight an infection already in the body. Someone may have been infected without knowing it before getting their shots.

Vaccines are not 100 percent
Through testing and clinical trials, the vaccines have been shown to be safe and effective, yet not 100 percent. The mRNA vaccines were shown to have efficacy rates in the mid-90, while others have been in the 70s, no vaccines (not even flu vaccines) are 100 percent effective against an illness.

It’s for these reasons, along with the potential for vaccinated individuals to transmit the virus, that health professionals say everyone should still continue the mitigation strategies of wearing a mask, social distancing and avoiding large crowds.

Infectious disease and public health experts remain strong advocates for getting the COVID-19 vaccine, also adding that the vaccines are effective against the numerous variant strains around the globe.