SAN ANTONIO — The Pfizer and Moderna vaccines share several similarities. One of those similarities is the need for booster shots, which isn't unusual. Several vaccines in the past have required two doses or more.
Experts say this is to help the body build up a defense against the virus.
Dr. Amesh Adalja, an infectious disease specialist offered the following explanation, "We know that there is some immunity that people will get after a single dose, but it may not be as durable, it might not last as long, and it may not be as strong as when you get two doses."
For people who get a Pfizer vaccine, the second dose will come three weeks after the first shot.
Moderna's booster comes four weeks later.
When you get the first dose of either vaccine, you'll be given a vaccine card reminding you to get the second dose, which must be the same vaccine as the first dose.
It is important not to mix doses from different makers. It's also important to note that not getting the second dose could limit the effectiveness of the vaccine.
The KENS 5 Vaccine Team is here to help you better understand the coronavirus vaccine. For more information visit our vaccine tracker here.