As of mid-March, experts say BA.2 makes up about a third of the cases of COVID-19 in the United States. But what does that mean and is it a cause for concern about another surge?

News, Coronavirus Updates | 2 months ago

Tracking the BA.2 Sub-Variant of Omicron

By now, you’ve no doubt heard that scientists are tracking a rise in COVID-19 cases in Europe caused by BA.2, a sub-variant of the omicron variant of COVID-19. As of mid-March, experts say BA.2 makes up about a third of the cases of COVID-19 in the United States. But what does that mean and is it a cause for concern about another surge? Dr. Anupama Neelakanta, an Atrium Health infectious diseases physician, helps explain what you need to know.

Editor’s Note: Information in this article is current as of March 24, 2022.

Since the start of the COVID-19 pandemic more than two years ago, we have experienced several types of variations of COVID-19. This is not unusual. All viruses mutate, or change, over time.

“Whenever a new variant comes up, there are small sub variations which occur in that variant due to minor changes in mutations,” Dr. Anupama Neelakanta, an infectious diseases physician at Atrium Health, explains. “BA.2 is a sub-variant to the omicron variant. It may have different names, like the 'stealth omicron,' but there really are minor differences to its communicability. It is thought to be slightly more transmissible than omicron itself, but not necessarily more severe.”  

Scientists are currently tracking a rise in cases caused by BA.2. It’s spreading rapidly in parts of Asia and in Europe. CDC officials recently said BA.2 accounts for about one-third of current COVID-19 cases in the United States.

“I think Europe is seeing another surge,” Neelakanta says. “But while they are seeing more cases, their hospitalizations have not gone up significantly. It’s difficult to predict if there will be a similar outcome in the United States. With the percentage of current COVID-19 cases caused by BA.2 right now, that does not indicate a surge, so I think we have to wait and watch.”

Vaccination rates in some parts of Europe are less than in the United States and some countries did not have as much of a surge in cases which we saw in December and January, which may be the reason for the second spike there.

COVID-19 cases have declined nationwide in recent weeks, leading to the relaxation of masking guidelines in our local communities, including schools, and across the country. Neelakanta believes Atrium Health and other health systems, nationwide, are capable of handling future surges better than when the pandemic started two years ago. That's due to a variety of reasons such as improved vaccination rates with less severe cases, availability of treatment options and lessons learned from previous surges, but stresses the importance of partnership with the community. And when it comes to wearing masks, she says, it’s about assessing your individual risks.

“Our advice hasn’t changed," Neelakanta says. "If you’re not vaccinated, get vaccinated. If you’re sick, stay home to prevent making others sick. It’s also important to assess your own risk with regard to mask wearing. Even if you live in a community with low transmission, if you are immunocompromised or care for people who are immunocompromised and may be at risk for severe complications with COVID-19, I think it is important to continue to mask indoors. But each individual needs to make decisions based on their respective health care issues.”

The World Health Organization has said initial data shows no significant difference in the severity of COVID-19 cases caused by the BA.2 sub-variant.

“BA.2 is thought to be slightly more communicable compared to omicron, which we already know to be more easily transmissible than other variants of COVID-19,” Neelakanta explains. “But more transmissible does not necessarily mean more severe disease. What we’ve seen so far has been that severity seems similar to omicron, which, in most cases, proved to be less severe than the delta variant.”

With vaccines, testing and treatment for COVID-19 widely available, we are in a better position now than ever before to face new variants or challenges associated with COVID-19.

“It’s hard to predict exactly what we’ll see in the future, but if there’s a high amount of immunity, through vaccination or natural infection, it puts us at an advantage and future surges could be smaller,” Neelakanta says. “I think the important message here is if someone has not been vaccinated, it’s really important to stay up to date, per the CDC’s definition of vaccination, so that we have those immunity levels to be prepared for whatever comes next.”