As health officials anticipate another wave of viral infections, the U.S. is facing at least seven different variants of the Covid-19 strain.
Although the omicron BA.5 variant is dominant in the country, other variants of the virus have begun to decline, according to Data from the Centers for Disease Control and Prevention Published on Friday.
The Omicron BA.5 has been split into several new but related variants including the BQ.1, BQ.1.1 and BF.7. UK Health Security AgencyIn a report earlier this monthThat said, these three variants show a growth advantage over BA.5, which was the most infectious version to date.
In the US, omicron BA.5 makes up about 68% of all new infections, down from about 80% in early October. BQ.1, BQ.1.1 and BF.7 now collectively account for about 17% of new infections, according to CDC data.
About 3% of new infections are attributable to BA.2.75. and the BA.2.75.2, which correspond to the omicron BA.2 variant that blocks the cases during the spring but was pushed out.
Scientists from Peking University in China found this omicron BA.2.75.2 and BQ.1.1 were the most adept at evading disease immunity. from previous BA.5 infection and multiple antibody drugs. The study, previously published in October, has not been peer-reviewed.
The White House’s covid response coordinator Dr. Ashish Jha said earlier this week that US health officials are Monitoring these types closely Because they are good at avoiding prior immunity.
“The reason we’re tracking them is because they either have very high resistance or they make many of our treatments ineffective,” Jha said. “Those are the two main things that get our attention.”
But Jha said the new Omicron boosters introduced by the US last month should offer better protection against these emerging strains than first-generation vaccines. Boosters target BA.5 and emerging variants are all omicron and most descend from BA.5.
Zha urged all eligible Americans to get a new booster by Halloween so they have full coverage for Thanksgiving when family holiday gatherings are in full swing.
But Peking University scientists said the immunogenicity of variants such as BA.2.75.2 and BQ.1.1 could mean that BA.5 booster shots would not provide broad enough protection.
It’s unclear how effective the boosters will prove in the real world. The Food and Drug Administration authorized the shots without actual human data, relying instead on clinical trials of a similar shot developed against the original version of omicron, BA.1.
Pfizer And Biotech on thursday First human data published From their BA.5 shots. They significantly boosted the immune system against omicron BA.5 in a laboratory study that looked at blood samples from adults 18 years and older, the companies said.