Known as "bivalent" vaccines, the updated doses contain half the original vaccine recipe and half protection against the newest omicron versions, BA.4 and BA.5.

Side effects caused by the boosters may not be that different from your last dose.

"We just don't have any data on this [yet], essentially giving two vaccines in one shot — but biologically, I just wouldn't expect the side effects, severity or the safety profile of the shots to be different from the current mRNA vaccines and boosters," Dr.

The Food and Drug Administration states that those who receive the bivalent vaccine "may experience side effects commonly reported by individuals who receive authorized or approved monovalent mRNA COVID-19 vaccines.".

The side effects were similar for both Moderna and Pfizer's vaccines and largely mirror expected side effects for earlier doses.

According to the Centers for Disease Control and Prevention, only those who have completed a full COVID vaccine series -- which consists of either two Moderna or Pfizer shots, or one Johnson & Johnson shot -- are eligible.