CHARLOTTE, N.C. — Walgreens is reportedly moving the spacing of the two-dose Pfizer COVID-19 vaccine to the recommended 21 days after it had been separating the doses by 28 days, which is how the Moderna vaccine is supposed to be administered.
But for customers who already received their Pfizer doses four weeks apart instead of three, are there any concerns with vaccine effectiveness?
A WCNC Charlotte viewer wrote in to ask that question:
I read today that Walgreens is being investigated for scheduling the Pfizer vaccine 28 days apart... I get my second shot tomorrow at Walgreens and it is 28 days (apart). I am concerned. What can you verify about this?
Should you be concerned about vaccine effectiveness if you got your Pfizer doses 28 days apart instead of the CDC-recommended 21 days apart?
No. The CDC says, while the recommended window for Pfizer doses is 21 days apart, people have up to 6 weeks to get that second dose.
The CDC guidance states, "If it is not feasible to adhere to the recommended interval and a delay in vaccination is unavoidable, the second dose of Pfizer-BioNTech and Moderna COVID-19 vaccines may be administered up to 6 weeks (42 days) after the first dose. Currently, only limited data are available on efficacy of mRNA COVID-19 vaccines administered beyond this window."
Dr. David Priest, an infectious disease specialist with Novant Health, said if logistics prevent sticking to the 21-day timing, people should not be concerned.
"I understand when people say I have to get my dose on this date, but the reality of logistics and human life is that it's sometimes hard to things on the exact date that you think it ought to happen. So, it's really general windows of time," Priest said.
Have a relative or friend in another state and want to know when they can get vaccinated? Visit NBC News' Plan Your Vaccine site to find out about each state's vaccine rollout plan.