LONDON - Scientists believe they have detected a sub-variant of the omicron variant, which has already been blamed for the latest wave of COVID-19 cases across the globe.
The UK Health Security Agency announced Friday that it was investigating an omicron sub-lineage known as BA.2.
"There is still uncertainty around the significance of the changes to the viral genome, and further analyses will now be undertaken," the agency said in a news release.
Scientists said early analysis seems to show that BA.2 is more transmissible than the first omicron strain, but they haven’t been able to spot any meaningful difference between the two strains. They add, as of Friday, there have been more than 400 confirmed cases of BA. 2 in 40 countries, with the first case being confirmed in December.
"So far, there is insufficient evidence to determine whether BA.2 causes more severe illness than Omicron BA.1, but data is limited and UKHSA continues to investigate," Dr. Meera Chand, COVID-19 incident director at UKHSA, said.
"It is the nature of viruses to evolve and mutate, so it’s to be expected that we will continue to see new variants emerge as the pandemic goes on," she continued. "Our continued genomic surveillance allows us to detect them and assess whether they are significant."
UKHSA said further research is needed to study BA.2.
The sub-variant was also detected in Washington, health officials announced Monday.
According to the U.S. Centers for Disease Control and Prevention, a variant "is a viral genome (genetic code) that may contain one or more mutations."
A variant could also achieve its main goal - replicating - if infected people developed mild symptoms initially, spread the virus by interacting with others, then got very sick later. To curb the emergence of variants, scientists stress continuing with public health measures such as masking and getting vaccinated. While omicron is better able to evade immunity than delta, experts said, vaccines still offer protection and booster shots greatly reduce serious illness, hospitalizations and deaths.
Omicron cases dropping in U.S.
World health officials are offering hope that the ebbing of the omicron wave could give way to a new, more manageable phase of the COVID-19 pandemic, even as they warn of difficult weeks ahead and the possibility of another, more dangerous variant arising.
In the U.S., cases have crested and are dropping rapidly, following a pattern seen in Britain and South Africa, with researchers projecting a period of low spread in many countries by the end of March. Though U.S. deaths — now at 2,000 each day — are still rising, new hospital admissions have started to fall, and a drop in deaths is expected to follow.
In the U.S., new cases are averaging a still extraordinarily high 680,000 a day, down from an all-time peak of over 800,000 a little more than a week ago.
Falling, too, are new U.S. hospital admissions of patients with confirmed COVID-19. They are averaging nearly 20,000 per day, down about 7% from the previous week, according to the Centers for Disease Control and Prevention
On Sunday, Dr. Anthony Fauci talked on ABC "This Week" about a "best-case scenario" where COVID-19 would fall to manageable levels so the United States could get "back to a degree of normality."
The Associated Press contributed to this story. This story was reported from Los Angeles.