Will Booster or Annual Doses of COVID-19 Vaccines Be Needed?

Dr. Hank Bernstein explains why booster or annual doses of COVID-19 vaccine are not currently recommended but why that may change over time.


Will Booster or Annual Doses of COVID-19 Vaccines Be Needed?

Hank Bernstein, MD: I'm Hank Bernstein and I'm speaking on behalf of the Vaccine Education Center at Children's Hospital of Philadelphia. The question, “Will booster doses of COVID-19 vaccines or annual vaccines be needed?” Those are million-dollar questions, and everyone's asking.

As you know, all but one of the COVID-19 vaccines that are currently in phase III clinical trials in the United States use two shots. The first shot is the shot that begins to build protection, and then a second shot is needed several weeks later to get the most protection possible that the vaccine can offer. The need for and the timing for booster doses of an mRNA COVID-19 vaccine has not been established. Remember these vaccines didn't even exist a year ago. So as of now, there are no recommended additional doses needed beyond the current two-dose primary series.

Now, this is a problem because as everyone's aware, there are now variants of the virus circulating around the world. And when that happens, it makes it quite possible that booster doses will be needed. Why? Because the vaccine is created in order to cover and protect for that particular virus strain. However, if it mutates, then the circulating virus will not match the virus that's in the vaccine and, therefore, the optimal protection will not be achieved.

We really don't know for sure what's gonna happen with all these variants, but there are more data being collected every day as time marches on. Subjects who participated in the first clinical trials continue to be monitored for at least two years after their introduction in this study. So, more information is anticipated, and we should all stay tuned.

Related Centers and Programs: Vaccine Education Center

Last Reviewed on Mar 16, 2021