Welcome to our Just Wondering series, in which local experts tackle your most burning health and fitness questions. Got a question of your own? Send it here!

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Booster Shot Arm
I’m one of those lucky people that hilariously unfortunate things tend to happen to. Sliding Superman-style down a flight of stairs at a local shopping center in the height of holiday season? That was me. And three months after receiving my second dose of the COVID-19 vaccine, I had a breakthrough case (true story!). It took about five days of straight naps before I finally felt like I could be vertical again.
With the booster available to all Minnesotans age 18 and up as of last Friday (November 19), I wondered if I needed it right away. I mean, if my immune system couldn’t ward off COVID after the first series of shots, I should probably stock up on this booster—right?
The standard waiting period for booster is six months after a second dose for Pfizer and Moderna and two months for the single shot Johnson & Johnson. So, I’m just wondering: If I had a breakthrough case, how long should I wait to get my booster shot? Should I still be rushing out to get it at the six-month mark for my vaccine? And does having a breakthrough COVID case function like a booster shot for my immune system?
“It is true that a breakthrough case of COVID can function like a booster for the immune system. In these individuals, the initial response to the vaccine likely waned leading to the breakthrough infection. We do know that those who have had an infection followed by a vaccine (hybrid immunity) have a very strong immune response. I think we know less when the events occur in the opposite order—when vaccine is followed by a breakthrough infection. In this situation, we don’t know how effective this immunity infection is at this point, but it would almost certainly provide protection for a period of time. I don’t think those that have a recent breakthrough case need to rush out to get a booster dose. I have recommended that my patients wait at least 90 days so that if a booster is given, it will have some benefit.” —Dr. Greg Siwek, Infection Disease Physician at Regions Hospital
DYK? The CDC stopped tracking breakthrough cases in May, but according to recent data reported by NPR, breakthrough cases comprise about 40 percent of total COVID infections.