March 9, 2022

I got my booster. What now?

A physician answers some of the common questions about the current state of the pandemic and COVID-19 vaccination.

Even if you have received your booster, you should follow basic steps to protect yourself and others.

We know the COVID-19 vaccines and boosters are effective at preventing people from getting severely sick. In fact, during the omicron surge, Kaiser Permanente members who were vaccinated but had not received a booster were twice as likely to be hospitalized as those who were vaccinated and boosted.

The proven effectiveness of boosters is why the Centers for Disease Control and Prevention recommends people to stay up to date by receiving all recommended COVID-19 vaccines, including any booster dose(s) when eligible. Everyone, including those who are up to date, should continue to take steps to keep themselves, their families, and their communities safe.

Craig Robbins, MD, medical director for the Kaiser Permanente Care Management Institute’s Center for Clinical Information Services and Education, answers questions about how to stay safe, even if you’re up to date.

Who can get a booster and when should they get it?

Recent data suggests the initial vaccination becomes less effective over time at preventing asymptomatic infection or mild illness. That’s why the Centers for Disease Control and Prevention and Kaiser Permanente recommend that everyone age 12 and older get a booster.

Initial vaccination Who can get the booster? When are you eligible? Which booster?

Anyone 12 or older

5 months after initial 2-dose series

For people age 12 to 17, only Pfizer. People 18 or older can get Pfizer, Moderna, or J&J*


Anyone 18 or older

5 months after initial 2-dose series

Moderna, Pfizer, or J&J*


Anyone 18 or older

2 months after first dose

Moderna, Pfizer, or J&J*

*Pfizer and Moderna are preferred over Johnson & Johnson in most situations. 

If you are immunocompromised, the CDC now recommends less time between completing your initial Pfizer or Moderna vaccination and getting a booster dose (at least 3 months instead of 5 months). And for those who are immunocompromised and received J&J for your initial vaccination, the CDC recommends receiving an additional Pfizer or Moderna vaccine dose and a booster dose, for a total of 3 doses to be up to date.

I’m vaccinated and boosted. Should I be worried about variants?

COVID-19 vaccines and boosters remain the best public health measure to protect people from COVID-19 and reduce the likelihood of new variants emerging. However, the recent omicron surge showed that breakthrough infections in people who are vaccinated can occur. People who are up to date with their COVID-19 vaccines and get COVID-19 are less likely to develop serious illness than those who are unvaccinated and get COVID-19. Therefore, your best protection against severe illness is to get vaccinated and receive a booster when eligible. Everyone age 12 and older is recommended to receive a booster.

Even if you get a booster shot, we strongly encourage you to take steps to protect yourself and your community. The CDC recommends continued mask use in public indoor spaces in communities where the COVID-19 community level is high. Also, you should still wear a mask if you wish to be cautious, if you are personally at high risk, or when you are with people at higher risk for severe illness. And regardless of local conditions, you should wear a mask if you have COVID-19 symptoms or a positive test or have been exposed to someone with COVID-19.

Can I spread the coronavirus if I’m fully vaccinated?

While fully vaccinated people are less likely to transmit the coronavirus to unvaccinated people, it is still possible to spread the virus. Please get tested if you are experiencing COVID-19 symptoms, even after you are fully vaccinated.

How can I help protect people who are not vaccinated or boosted?

Protecting yourself also protects the community and the people around you, especially those at increased risk of severe illness from COVID-19. These precautions also protect people who can’t get vaccinated, including people with weakened immune systems from things like chemotherapy for cancer.

You can also encourage family members and friends who are 5 and older to get vaccinated as soon as possible and those 12 and older to get boosted as soon as they are eligible. They can get a no-cost COVID-19 vaccination or booster at Kaiser Permanente or any authorized vaccination provider. Both members and nonmembers can go to or call our KP COVID Vaccine InfoLine at 1-855-550-0951, available 24/7, for the latest information and to make an appointment.