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Published on May 25, 2021


Why You Shouldn’t Skip the Second COVID Vaccine Shot

Recent data indicates that about 8% of people nationwide are past due on their second COVID-19 vaccine shot.

The South Dakota Department of Health estimates thousands are behind in the state.

Here’s why that’s not a good idea.

If you get a two-dose vaccine, such as Moderna or Pfizer, the first dose is a “priming” dose giving you partial immunity while the second dose sets in immunity to around 94 to 95%.

You’re considered to have full immunity about two weeks after the second dose. You will not develop sufficient immunity to COVID-19 without both doses.

“It’s that second shot that really gets that antibody level up, to a much higher level than just one shot gets it to. It also holds it up there for a longer period of time,” said David Basel, MD, Vice President of Clinical Quality with Avera Medical Group.

That higher level of immunity is particularly important for protection from the variants.

“The variants have a little bit tighter binding to the cells and so it requires that higher level of antibodies to be able to effectively fight them and so that second shot is just critical with these new variants particularly,” Basel said.

If you got the Pfizer of Moderna shot and missed the second shot, there still may be time. While it’s best to get the second shot as close to the recommended time as possible (21 days for Pfizer and 28 days for Moderna), the shot may be given up to six weeks after the first dose, according to CDC guidelines.

Basel added that the data does show that people who missed their shot typically missed it because they couldn’t make their appointment, such as due to sickness or being exposed to COVID.

If you have questions about the vaccine, Basel recommends talking with your provider about your concerns. You can also go to the Avera COVID-19 vaccine website for answers to common questions or to find a vaccine location.

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