What Are Side Effects of New COVID Booster? CDC Recommends Vaccine

As respiratory virus season approaches in the United States, health officials are rolling out a fresh batch of updated COVID-19 boosters nationwide.

The new vaccines, which have been reformulated to target new variants, are recommended for everyone ages 6 months and older. Americans can expect the updated shots to become available as early as Friday in some parts of the country.

Earlier this week, the U.S. Food and Drug Administration authorized the updated mRNA vaccines for 2023-2024 from drugmakers Moderna and Pfizer-BioNTech.

Following the FDA’s green light, the U.S. Centers for Disease Control and Prevention’s advisory committee met on Tuesday, Sept. 12, to vote on recommendations for who should get the new booster and when. Advisers overwhelmingly recommended that everyone ages 6 months and older get the updated vaccines this fall to protect against potentially serious outcomes of COVID-19.

The CDC’s director Dr. Mandy Cohen signed off on the new recommendations Tuesday evening, kicking off a new nationwide COVID-19 vaccination campaign, NBC News reported.

“We have more tools than ever to prevent the worst outcomes from COVID-19,” Cohen said in a statement.

The broad vaccination recommendations come as the U.S. faces an uptick in infections and hospitalizations around the country. During the week ending on Sept. 2, 18,871 people were hospitalized with COVID, an 8.7% increase from the previous week, per the CDC.

The newest COVID-19 booster is a vaccine that targets the omicron XBB.1.5 variant of the coronavirus.

Although many are referring to the updated vaccine as a booster, the shot looks different from its predecessors. It may be first of what will become an “annual COVID-19 shot” that gets revamped every year, similar to the seasonal influenza vaccine, Dr. Mark Mulligan, director of NYU Langone Vaccine Center, tells TODAY.com.

Unlike the last round of boosters, the updated mRNA vaccines are monovalent, which means they target a single variant. The previous vaccine rolled out last fall was bivalent, meaning it included two strains — the original SARS-CoV-2 virus and the omicron BA.4 and BA.5 subvariants, says Mulligan. The bivalent vaccine is no longer authorized by the FDA, the CDC said.

The XBB.1.5 subvariant targeted in the new vaccines was the dominant COVID strain in the U.S. for most of 2023. In recent months, it has been overtaken by new strains including the EG.5 or “Eris” subvariant, F.L.1.5.1 (also dubbed “Fornax”), and XBB.1.16 or “Arcturus” — which are all descendants of the omicron XBB lineage and close relatives of XBB.1.5, TODAY.com reported previously.

The updated vaccines are expected to provide good protection against the variants currently circulating, the FDA said.

Last month, a highly mutated new variant called BA.2.86 or “Pirola” gained global attention after health experts predicted it may be better able to bypass immunity from vaccination and prior infection. However, new data suggests that BA.2.86 may not be as immune-evasive as initially thought, and that the updated COVID shots will likely still be effective against the mutated strain.

Last week, Moderna said…