Severity of ‘stealth omicron’ varies by country’s vaccination rate

CBS News Medical Contributor Dr. David Agus tells WTOP what the U.S. should expect from the omicron subvariant.

As many COVID-19 mitigation measures have been lifted in the D.C. area, a mutant of the virus has been emerging and is now causing a new wave of omicron cases around the world.

It’s called BA.2, and it’s been described as “stealth omicron” because “it lacks a genetic quirk of the original omicron that allowed health officials to rapidly differentiate it from delta using a certain PCR test,” The Associated Press reported. What could actually be a BA.2 infection looks like a delta infection.



CBS News medical contributor Dr. David Agus said BA.2 is quite different from BA.1, the original omicron variant, but experts believe it has a similar illness rate. You can find out more about BA.2 here.

On Thursday, he said 75% of cases worldwide are caused by BA.2; 25% of cases in the U.S. It’s also rapidly rising in countries that have a high incidence of vaccinations, such as New Zealand, which has a record case number but almost no hospitalizations.

However in Hong Kong, Agus said, one in 20 is dying from the virus because 60% of people over 60 years old are not vaccinated.

“The problem is, if you have no vaccine and you had some immunity to BA.1, you’re not going to have that much immunity to BA.2,” Agus said, adding that results differ depending on the vaccination rate of the country.

With about 65% of people vaccinated in the U.S. and some immunity for people who have been exposed but weren’t vaccinated, “My gut is we’re going to do OK with the BA.2 variant,” Agus told WTOP.

Vaccination is key in preventing what’s happening in Hong Kong from happening in the U.S.

“The more people are vaccinated, the better we’re going to do. Our hospitals won’t be full, and we’ll be able to care for people with other medical issues in the country,” Agus said.

The vaccines block hospitalization and serious illness, but what they don’t do is block the ability to transmit the virus, Agus said.

“They work really well on lower respiratory, which is what hospitalized you, but on upper respiratory, they weren’t as good, and so it’s still contagious. So we have to be aware of both of those things,” he said.

In addition to the vaccines, there is also Pfizer’s coronavirus pill, which has been found to cut the risk of hospitalization or death and is also thought to be effective against the omicron variant.

“So if someone does have significant medical issues and does test positive, we can treat them and that will also help block hospitalization,” Agus said.

Abigail Constantino

Abigail Constantino started her journalism career writing for a local newspaper in Fairfax County, Virginia. She is a graduate of American University and The George Washington University.

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