How long after exposure to COVID can a test detect the virus? When should I get my booster shot?

Dr. Frank McGeorge answers COVID questions

Since the coronavirus pandemic began, Dr. Frank McGeorge has been keeping viewers up-to-date and informed on all fronts. He’s been answering your questions about the vaccine, the vaccination process and more.
Since the coronavirus pandemic began, Dr. Frank McGeorge has been keeping viewers up-to-date and informed on all fronts. He’s been answering your questions about the vaccine, the vaccination process and more.

DETROIT – Since the coronavirus pandemic began, Dr. Frank McGeorge has been keeping viewers up-to-date and informed on all fronts. He’s been answering your questions about the vaccine, the vaccination process and more.

Read: More answers to questions about coronavirus


My husband and I have breakthrough cases of COVID-19. His fever and symptoms have cleared, but mine have not. He is nearing the end of the ten days since the onset of his symptoms. Should we both quarantine until after my fever is gone?

If his symptoms have resolved and ten days have passed he can come out of his isolation. Although, you are potentially still infected. He is most likely completely resolved and no longer contagious.

How long before a person exposed to COVID can be detected in a test? If a person was exposed to someone who has COVID and gets tested two hours later, will the results be accurate?

What you want to know is how long it takes before an infected person will have a positive test. Generally, the answer is three to five days with a PCR test. Testing immediately after exposure, two hours in your example, is way too early. In fact, you aren’t technically even infected after two hours. The incubation period for COVID is generally at least two days.

I had my second Pfizer vaccine in mid-February 2021. Should I hold off getting my booster shot until I’m in a more risky situation like flying to Portland for Thanksgiving?

If you qualify for a booster and you are trying to optimize your protection for Thanksgiving you should get the booster as soon as you are due. Optimal immunity still doesn’t occur for two weeks after the shot.

I’m 71 years old. I need a flu shot, pneumonia shot, and a COVID booster. What order should I get them in?

In your specific case, I would recommend getting the COVID booster and then waiting two weeks and getting influenza and pneumonia vaccines at the same time. The main reason is that while it’s completely acceptable to get the COVID vaccine with one other vaccine, the effect of getting it with two other vaccines is unknown.

How long should I wait between getting the first or second COVID shot and a flu shot?

You do not need to wait. You can get them at the same time. However, if you choose to do them on different days the suggested wait time is 14 days between shots.

Read: Complete Michigan COVID coverage


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About the Authors:

Dr. McGeorge can be seen on Local 4 News helping Metro Detroiters with health concerns when he isn't helping save lives in the emergency room at Henry Ford Hospital.

Kayla is a Web Producer for ClickOnDetroit. Before she joined the team in 2018 she worked at WILX in Lansing as a digital producer.