AMARILLO, Texas (KFDA) - Both the Pfizer and Moderna vaccines require two doses of COVID-19 vaccine to reach more than 90 percent efficacy rate.
For the Moderna vaccine the recommended time to get the second dose is 28 days after the first one.
For Pfizer the second dose should be administered 21 days after. But, what happens if you wait longer?
The CDC says you may delay getting the second dose of the COVID-19 vaccine without having to restart the series.
However, at the moment that window to safely delay the second dose is up to 42 days.
The reason for the 42 day window, is that the clinical trials done to ensure the vaccine was safe tested around that 18 to 42-day range for efficacy.
“After that, right now we just don’t know. That is not the recipe that we were handed, so we are not sure. We may find that in a couple months we have more data and long behold people may be able to wait three months or four months but right now we just don’t know,” said Todd Bell, M.D., associate professor, Texas Tech University Health Sciences Center.
He describes the process of getting both within the suggested time frame like following a recipe.
You could change the process a little and it might still taste fine, but the intended result is not guaranteed as if you were following the recipe as suggested.
He notes the second dose for both Pfizer and Moderna does usually have stronger side effects but that is because your immune system is responding the way it should and this should not discourage anyone from getting it.
“What we see is that if somebody has an exposure to an illness, and then soon thereafter has another exposure to the same illness then they are going to have more of a long lasting immune response than if they would have been exposed to the illness once,” said Bell.
This is important when it comes to the new variants developing.
“The more people that are infected, the more opportunities the virus has to mutate.” said Bell.
He adds that the earliest you can receive the second dose, the faster you will reach full protection.
According to the CDC, full protection is not reached until two weeks after the second dose is administered.
Bell adds this is why it is important to receive both doses and why everyone should continue to follow CDC guidelines like wearing masks and social distancing.