BA.2, the highly contagious omicron subvariant of COVID-19 driving yet another surge of cases in Europe, has reached D.C., a District health official said Friday.

It’s not immediately clear when BA.2 arrived in D.C., but a new study suggests the first known case of the subvariant in the U.S. was detected in December. BA.2 is estimated to be 30 to 50% more contagious than the original version of omicron, but early data signals some good news. “It doesn’t seem to evade our vaccines or our immunity any more than the prior omicron,” CDC Director Rochelle Walensky told NPR last week. “And it doesn’t seem to lead to any more increased severity of disease.”

The subvariant’s trajectory in Europe is significant because the U.S. has typically followed it a few weeks later. In the U.K., for example, cases have more than doubled and hospitalizations look to be increasing, statistics health officials there are attributing to BA.2.

Multiple public health experts expect BA.2 could lead to an increase in cases reported locally, however they do not anticipate seeing the record-breaking counts of late 2021 when omicron first appeared. So what should local residents expect? DCist/WAMU tried to answer a few questions readers might have.

Is BA.2 the dominant variant in D.C.? 

Not yet. BA.2 currently accounts for roughly 29% of new cases in the District, DC Health senior deputy director Patrick Ashley told the D.C. Council on a call Friday. The original omicron variant still makes up the majority of new infections, around 59%, he said, numbers that reflect national and global trends. The CDC reported Tuesday that BA.2 made up 35% of infections in the U.S., up from 22% a week prior.

Have cases in the District increased because of BA.2?

It’s unclear. DC Health reported a slight increase in the weekly case rate this week, 62.5 cases per 100,000 as of March 13, up from 44.9 the prior week. Even so, the health agency says the risk of COVID-19 to the community remains low. Case counts remain flat in the District, according to The Washington Post’s tracker. That’s also the case in Northern Virginia and suburban Maryland, where the steep declines from January’s omicron peak have leveled off.

D.C. is not seeing the subvariant’s high transmissibility correspond to case rates, Ashley added in the council call. He speculated many residents have natural immunity to the subvariant because D.C. was hit hard by the original omicron. D.C. reported the highest daily case rate nationwide in late December, suggesting there is a lot of natural immunity.

Dr. Andy Pekosz, a virologist at the Johns Hopkins Bloomberg School of Public Health, backs up Ashley’s theory, noting studies suggest that someone will be protected from BA.2 if they have already been infected with the original omicron variant. Pekosz is also encouraged because BA.2 is not following the trajectory of its predecessor, known as BA.1. “When BA.1 came in the population, not only did the percentage of cases caused by BA.1 increase quickly, but even the total number of cases increased phenomenally fast,” he tells DCist/WAMU.

It will also be difficult to determine whether cases are increasing due to BA.2 or because local governments and businesses have eased COVID-19 measures, Pekosz adds. Just this month, regional schools dropped mask mandates. “You expect to see a small bump in cases just because we’re no longer doing the things that kept infections down,” he says.

What is local government doing to prepare?  

The D.C. government’s coronavirus mitigation strategies have not changed significantly due to the new subvariant, Ashley said Friday. Mayor Muriel Bowser’s administration is not currently considering reinstating the mask mandate, he said, and he didn’t offer any specific metrics that would prompt the reinstatement of either the mask or vaccine mandate. Ashley did stress the health department’s surveillance activities, which will soon include regular wastewater surveillance — the “literal analysis of feces,” as Axios put it — to combat the downtick in people taking COVID tests and submitting their results.

DC Health has no plans to discontinue existing vaccination or testing sites, Ashley said. Elsewhere in the region, though, large localities such as Fairfax and Loudoun counties have closed down large-scale testing and vaccination sites.

Notably, as BA.2 cases increase, D.C. officials have stopped publicly reporting daily COVID-19 data. Individuals who are interested in keeping tabs every day can use the Post’s tracker, which is updated daily with CDC numbers, according to Jacqueline Dupree, who tracks state health department data for the Post. Pekosz, meanwhile, recommends residents enjoy the lull between COVID-19 waves and perhaps not fixate on the daily counts.

Margaret Barthel contributed reporting.