Omicron Subvariant Doesn't Make People Sicker Than Original Omicron, WHO Says

Ralph Ellis

February 02, 2022

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While studies indicate the Omicron subvariant spreads more easily than the highly transmissible original Omicron variant, there's no evidence the subvariant makes people any sicker, a World Health Organization official said, according to CNBC.

Maria Van Kerkhove, WHO technical lead, said Tuesday at a news conference that both the Omicron variant, labeled BA.1 and the subvariant, BA.2, cause less severe illness than the Delta variant.

But there's no indication the subvariant causes more severe illness than the original Omicron, she said. Vaccines protect people from illness and death from both the variant and the subvariant, she said.

"We need people to be aware that this virus is continuing to circulate and it's continuing to evolve," Van Kerkhove said. "That's why it's really important that we take measures to reduce our exposure to this virus, whatever variant is circulating,"

The WHO named Omicron "a variant of concern" in November. The subvariant, BA.2, has not been recognized as a separate variant of concern.

"BA.2 is one of the sublineages of Omicron, so BA.2 is omicron, and it is a variant of concern," Van Kerkhove said. "It's in the family of the variants of concern around Omicron."

Denmark has reported the highest number of Omicron subvariant cases, followed by the United Kingdom and India.

A study conducted by Danish scientists showed that BA.2 is much more transmissible than BA.1 among vaccinated and unvaccinated people, spreads easily across all groups, and is "adept" at infecting vaccinated and boosted people, CNBC reported. That indicates BA.2 is better at evading vaccines than BA.1.

But researchers found that vaccinated people who are infected with BA.2 don't transmit the virus as easily as the unvaccinated, according to the study. Boosted people transmitted the virus less than fully vaccinated people.

Among the unvaccinated, transmission rates were higher with BA.2 than BA.1, indicating unvaccinated people were carrying a higher viral load with the subvariant, CNBC said.

Scientists affiliated with the University of Copenhagen and the Danish Health Ministry conducted the study, which has not been submitted for peer review.

Last week, the Statens Serum Institut, which monitors infectious diseases in Denmark, reported that the omicron subvariant is 1.5 times more transmissible than the original omicron strain.

The World Health Organization has said the probability for spreading within a household was 39% for BA.2 and 29% for BA.1.


CNBC. "WHO says the new omicron subvariant doesn't appear to be more severe than the original." "The omicron subvariant is more contagious, but vaccinated people are less likely to spread it, study finds."

MedRxiv: "Transmission of SARS-CoV-2: Omicron VOC subvariants BA.1 and BA.2: Evidence from Danish Households."


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