Pfizer‘s and Moderna‘s omicron booster shots reduced the danger of mild illness from the XBB family of subvariants by about 48% in comparison with individuals who didn’t receive the vaccine, in line with a study from the Centers for Disease Control and Prevention.
The CDC study published Wednesday provides the primary estimate of the omicron booster shots’ real-world effectiveness against the XBB family of subvariants. Some scientists have warned the XBB subvariants could cause one other Covid wave because they’re so good at evading the antibodies that block infections.
CDC officials, in a call with reporters Wednesday, said the study results are reassuring because individuals who received the boosters had more protection than those that didn’t. Protection against severe illness must be even higher, they said.
“It cuts your risk of symptomatic infection in about half on the population level,” said Dr. Ruth Link-Gelles, a CDC officials and writer on the study.
“What we all know from past experience is mostly that the vaccines protect higher against more severe disease,” Link-Gelles said. “So these are estimates for symptomatic infection and we might expect that similar estimates for hospitalization and death can be higher.”
The study compared individuals who received the brand new booster with those that received between two and 4 doses of the unique vaccine. The boosters goal omicron BA.5 and the unique strain of Covid that emerged in Wuhan, China, while the old shots only goal the unique virus strain.
Individuals who only received the unique shots generally got their last dose about 13 months ago. That they had little or no protection against mild illness as a consequence, because of waning immunity observed with the old vaccines, in line with CDC officials.
The XBB.1.5 subvariant is quickly rising to dominance within the U.S. and currently makes up about 49% of latest Covid cases nationwide. Officials on the World Health Organization have described XBB.1.5 as essentially the most transmissible version of the virus yet, though it doesn’t have any mutations that will suggest it makes people sicker than other subvariants.
XBB.1.5 may be very immune evasive and has mutations that allow it to bind higher to human cells. However the CDC study found that the omicron boosters provide about as much protection against the XBB family as they do against the BA.5 subvariant and its descendants corresponding to BQ.1 and BQ.1.1.
This can be a developing story please. Check back for updates.