The CDC study provides the first estimate of the omicron shots’ real-world effectiveness against the XBB family of subvariants. Some scientists have warned the XBB subvariants could cause another Covid wave because they are so good at evading the antibodies that block infections.

CDC data shows the bivalent COVID vaccines protect against the omicron variant known as XBB and its subvariant XBB.1.5.

The updated COVID-19 booster shots are at least 40% effective against symptomatic infection from omicron subvariants XBB.1.5 and XBB among fully vaccinated adults within three months of the shot’s administration,

County officials cited a new study released by the Centers for Disease Control and Prevention as they continue to urge local residents to take the bivalent COVID-19 booster.

In a study released today by the Centers for Disease Control and Prevention, a single bivalent COVID-19 vaccine booster provided additional protection against omicron XBB variants in adults who previously received two to four monovalent vaccine doses.

XBB.1.5 is a spinoff of XBB, a subvariant of omicron that health officials worldwide have been warning about since the fall. XBB.1.5 is considered a recombinant virus because it carries genetic data from two previous mutations,