The Omicron BA.5 subvariant is no longer the dominant cause of Covid-19 infections in the United States, according to estimates released Friday by the US Centers for Disease Control and Prevention.
Instead, a host of new sublineages – offshoots of BA.2, BA.4 and BA.5 – are now responsible for the majority of new infections in this country. Dr. Peter Hotez, director of the Center for Vaccine Development at Texas Children’s Hospital, calls these many new lineages “Scrabble variants” because they contain letters like X and Q that get high scores in the game.
The new variants descend from slightly different branches of the Omicron family tree, but they have evolved to share some of the same changes in their genomes that help them slip past our immunity against the virus.
The gaggle of new variants have been gaining ground against BA.5, which has dominated Covid-19 infections in the United States since July. BA.5 now accounts for 49.6% of new infections in this country.
Two variants, BQ.1 and BQ.1.1, have been growing especially fast. At the beginning of October, each one accounted for about 1% of new infections in the United States, but they have been roughly doubling in prevalence each week. Together, they now account for more than 1 in 4 new Covid-19 infections nationwide, according to CDC data.
BQ.1 is causing about 14% of new infections; BQ.1.1. is causing 13% of new infections. BA.4.6 is causing another 10%. BF.7 accounts for 7.5% of newly diagnosed Covid-19. A slew of other new variants accounts for smaller pieces of the Covid-19 pie.
These variants are not evenly distributed across the US. BQ.1.1 is now causing about 1 in 5 new Covid-19 infections in the Northeast, where cases and hospitalizations are rising. But that strain is causing just 3% of new Covid-19 infections in the Pacific Northwest.
These variants are slightly different from each other, but they all carry some of the same key mutations that help them skirt immunity from vaccines and past infections. This makes them more likely to lead to breakthrough infections and reinfections.
In a statement released Friday, the World Health Organization’s Technical Advisory Group on SARS-CoV-2 Virus Evolution said the most mutated families of the rising subvariants – XBB and BQ.1 – aren’t different enough from Omicron to be considered separate variants of concern.
XBB was detected in the United States in September, but it is not causing a significant number of cases in this country. It is particularly widespread in Singapore, where it is now the dominant circulating strain.
“The two sublineages remain part of Omicron, which continues to be a variant of concern,” the group said in a statement.
Image Credit: Envato Elements

News
Silver nanoparticles show promise in fighting antibiotic-resistant bacteria
In a new study, scientists with the University of Florida have found that a combination of silver nanoparticles and antibiotics is effective against antibiotic-resistant bacteria. The researchers hope to turn this discovery into viable [...]
Combating severe cancer with a new drug delivery system
Peritoneal cancer is difficult to treat and has a poor survival prognosis. But a new and effective nanomedicine delivery system is offering some hope. The company is called NaDeNo and is well underway with [...]
New Research Shows How Ketamine Acts As “Switch” in the Brain
According to a new study by researchers at Penn Medicine, ketamine, which is well-known as an anesthetic and is becoming increasingly popular as an antidepressant, dramatically reorganizes activity in the brain, almost as if [...]
Supercharged T Cells: A New Way To Kill Pancreatic Cancer With Minimal Side Effects
A new immunotherapy releases cancer-killing cytokines only within the tumor. Researchers at the University of California San Francisco (UCSF) have developed a new T cell-based immunotherapy that selectively targets cancer cells, producing a powerful anti-cancer cytokine [...]
AI has designed bacteria-killing proteins from scratch – and they work
An AI was tasked with creating proteins with anti-microbial properties. Researchers then created a subset of the proteins and found some did the job. An AI has designed anti-microbial proteins that were then tested [...]
Using nanoparticles, researchers can identify and deliver synergistic combinations of cancer drugs
Treating cancer with combinations of drugs can be more effective than using a single drug. However, figuring out the optimal combination of drugs, and making sure that all of the drugs reach the right [...]
Humanity May Reach Singularity Within Just 7 Years, Trend Shows
By one unique metric, we could approach technological singularity by the end of this decade, if not sooner. A translation company developed a metric, Time to Edit (TTE), to calculate the time it takes for professional [...]
HYPER (Highly Interactive Particle Relics) – A New Model for Dark Matter
Phase transition in early universe changes strength of interaction between dark and normal matter. Dark matter remains one of the greatest mysteries of modern physics. It is clear that it must exist, because without [...]
New Nanoparticles Deliver Therapy Brain-Wide and Edit Alzheimer’s Gene
Summary: Researchers have developed a new family of nano-scale capsules capable of carrying CRISPR gene editing tools to different organs of the body before harmlessly dissolving. The capsules were able to enter the brains of [...]
Cancer’s Secret Weapon? Enzyme That Protects Against Viruses May Fuel Tumor Evolution
An enzyme that defends human cells against viruses can help drive cancer evolution towards greater malignancy by causing myriad mutations in cancer cells, according to a study led by investigators at Weill Cornell Medicine. The [...]
Scientists Uncover Japanese Fruit Juice That May Help Prevent Lung Cancer
Using a mouse model, Japanese researchers unleash the likely mechanism of action of Actinidia arguta (sarunashi) juice on lung cancer development. Lung cancer is a leading cause of death in Japan and across the [...]
In-place manufacturing method improves gas sensor capabilities, production time
When used as wearable medical devices, stretchy, flexible gas sensors can identify health conditions or issues by detecting oxygen or carbon dioxide levels in the breath or sweat. They also are useful for monitoring [...]
In the core of the cell: New insights into the utilization of nanotechnology-based drugs
Novel drugs, such as vaccines against covid-19, among others, are based on drug transport using nanoparticles. Whether this drug transport is negatively influenced by an accumulation of blood proteins on the nanoparticle’s surface was [...]
The costly lesson from COVID: why elimination should be the default global strategy for future pandemics
Imagine it is 2030. Doctors in a regional hospital in country X note an expanding cluster of individuals with severe respiratory disease. Rapid whole-genome sequencing identifies the disease-causing agent as a novel coronavirus. Epidemiological [...]
How Artificial Intelligence Found the Words To Kill Cancer Cells
A predictive model has been developed that enables researchers to encode instructions for cells to execute. Scientists at the University of California, San Francisco (UCSF) and IBM Research have created a virtual library of thousands of “command sentences” [...]
Next-generation, light-activated nanotech for antibiotic-resistant superbugs
It's "lights out" for antibiotic-resistant superbugs as next-generation light-activated nanotech proves it can eradicate some of the most notorious and potentially deadly bacteria in the world. Developed by the University of South Australia and [...]