Lab study shows 'stealth omicron' subvariant is more transmissible as cases spread

Virus Outbreak Pennsylvania
Posted at 5:53 AM, Feb 22, 2022
and last updated 2022-02-22 12:34:08-05

TAMPA, Fla. — Stealth omicron is a subvariant of omicron.

“It’s a brother or a sister of the omicron that we went through with this wave. It has many of the same mutations but it also has a set of different mutations,” said Dr. Michael Teng, Virologist and Associate Professor for USF Health.

The reason it’s called stealth omicron, also known as BA.2, is because it’s harder to detect on PCR tests. Labs have to take an extra step and sequence the virus to find this version of the variant.

The original omicron, also known as BA.1, is already highly contagious.

New lab experiments from Japan show stealth omicron might be even more transmissible.

“It looks like it replicates a little bit better than regular omicron. So I think they were estimating something like 30% more transmissible,” said Teng.

Researchers believe stealth omicron is spreading faster.

According to theWorld Health Organization, the subvariant has been detected in at least 74 countries and 47 states, including Florida.

That new report out of Japan shows it could also be resistant to some treatments, like monoclonal antibodies.

“The good thing is that the vaccine efficacy against this BA.2 is pretty much exactly the same as BA.1. So if you’ve been vaccinated, boosted, your immune system is going to recognize just like it did the other one,” said Teng.

Some experts think stealth omicron could be the reason COVID-19 cases have stalled a little.

It’s taking longer to get over this wave than they’ve seen previously and believe this new subvariant could be to blame.

“What we’re seeing a little bit of in the United States with the omicron surge is that it went up, it spiked really quickly and it’s coming down but usually it goes up and down at the same speed and this one is kind of coming down a little slower,” said Teng.

The Centers for Disease Control and Prevention said it's watching this subvariant closely and all emerging data.

As for what’s next, experts say that’s hard to plan for since COVID-19 variants have come from all around the world.

“This is the one thing about the pandemic, it’s been really unpredictable. We don’t know when the next variant is coming out. We don’t know where it’s coming out,” said Teng.