Two people with masks sit far apart from each other on a bench to help prevent the spread of COVID.

Can vaccinated people spread COVID-19?

This article was updated July 5, 2023, to reflect new information from the CDC.

There are two big questions many people about COVID-19. Can you get COVID after being fully vaccinated? And can you spread COVID if you are vaccinated?

Two women touching elbows with masks

The short answers are yes and yes.

“Vaccinated people can become infected with COVID-19 and spread it to others. However, a 2023 study found that vaccinated people were significantly less likely to transmit the virus,” said Brian Laird, PharmD, a manager in Pharmacy Operations at OSF HealthCare.

Chances of getting COVID after being vaccinated

Scientists continue studying how the vaccine can prevent you from spreading COVID and becoming reinfected.

“We are still learning about the virus as it changes,” Brian said. “It’s only been identified for three and a half years. That is an incredibly short period of time when compared to other viruses.”

Data from the U.S. Centers for Disease Control and Prevention (CDC) shows COVID-19 breakthrough cases occur in fully vaccinated people.

“Breakthrough infections – getting COVID after a vaccine – are relatively common with COVID-19,” Brian said. “Their level of risk depends on mask wearing, amount of time spent around other people and whether they’re vaccinated.”

In these instances, however, symptoms often are mild and the individual doesn’t require medical care or hospitalization.

Can you be a carrier of COVID after vaccine?

Need a COVID-19 vaccine?

Sign up today

Vaccinated individuals have a lower viral load if they get infected. But they still can pass it on to someone else, Brian said.

Viral load means the amount of virus an infected person produces. If the viral load is significantly less due to vaccination, there’s less risk of transmitting the virus to others.

So can vaccinated people spread COVID to a friend or family member who is not vaccinated? It can happen.

“Very few things in medicine have a 0% chance of happening,” Brian said.

People who are immunocompromised and are vaccinated still are at high risk of severe illness or hospitalization due to COVID-19. They should wear a mask and practice other precautions.

“And asymptomatic COVID infections – when someone doesn’t experience any symptoms – still happen,” Brian said. “It is possible to spread the infection without realizing it. As more research is done on the virus, other signs or symptoms may be discovered.”

Vaccinations are key

Getting vaccinated is still recommended for the vast majority of the population.

“This will not completely prevent getting COVID though,” Brian said. “Breakthrough infections still happen, but they tend to be less severe than if a vaccine was never given.”

COVID-19 vaccines help protect against severe illness, hospitalization and death. People who are up to date on COVID-19 vaccines are much less likely to experience severe symptoms.

It’s important, Brian said, to remember how vaccines work. Vaccines are meant to protect you from getting seriously ill, not prevent you from becoming infected.

“In general, vaccines work by allowing your own body to produce antibodies. Those antibodies mount a defense against the disease for which you’ve been vaccinated,” he said. “Your body then remembers what to do if it encounters pathogens from that disease in the future. When that happens, the immune system shuts down the virus before any damage is done.”

So far, the COVID-19 vaccines have needed to be updated to remain effective against variants.

“For at least the near future, it appears yearly updates to the vaccine will continue” much like annual flu vaccines, Brian said.

“This does not mean the vaccine is ineffective. It just means for the best protection of the public, a change in the vaccine is warranted.”

Last Updated: July 5, 2023

Follow Us on Social Media

About Author: Lisa Coon

Lisa Coon is a Writing Coordinator for OSF HealthCare, where she has worked since August 2016.  A Peoria native, she is a graduate of Bradley University with a degree in journalism. Previously, she worked as a reporter and editor at several newspapers in Iowa and Illinois.

She lives in Groveland with her husband and son. In her free time she likes to cook, bake and read. She freely admits that reality TV is a weakness, and she lives by the quote, “The beach is good for the soul.”

View all posts by

Tags: , ,

Categories: COVID-19, Preventive Health