New COVID-19 variant detected in Washington state. Here’s what to know
Last week, the World Health Organization designated NB.1.8.1, a new strain of COVID-19 that’s been rising in frequency lately, as a “variant under monitoring.” Now, Washington state has its first case.
The case was detected by a Centers for Disease Control and Prevention surveillance program at the Seattle-Tacoma International Airport, according to a statement sent to McClatchy by the Washington State Department of Health.
“There appears to be a single detection of NB.1.8.1 in Washington state,” the statement said. “The sample was collected on May 15th 2025 by Ginko Bioworks, the industry partner for CDC’s Traveler Genomic Surveillance Program. This means this sample was captured via a CDC program, not a WA surveillance system.”
Washington is one of four states where airport screening has detected the new variant, along with California, New York and Virginia. Reports suggest that only a handful of states have detected the variant, which has yet to become common enough for the CDC to include it on its COVID-19 variant tracking dashboard.
The variant has been linked to a recent spike in COVID-19 cases in China, leading to concerns it could spread quickly in the U.S. However, officials say the early indications are that the variant doesn’t pose much of a threat. Here’s what to know about NB.1.8.1 in Washington.
What is NB.1.8.1?
According to WHO, the frequency of NB.1.8.1 cases quadrupled during April. The variant accounted for 2.5% of COVID-19 samples obtained over the week ending April 6. By April 27, that number had risen to 10.7%.
But despite the sharp rise, health officials say that the case doesn’t necessarily pose a threat to the public.
According to WHO, there isn’t much evidence that NB.1.8.1 is any more dangerous than existing variants.
“The additional public health risk posed by NB.1.8.1 is evaluated as low,” WHO’s latest report on the strain says.
That’s largely due to the fact that early evidence indicates available COVID vaccines protect against the severe illness in patients with the new variant.
NB.1.8.1 risk in WA
WHO did note that some countries have seen an increase in cases and hospitalizations as NB.1.8.1 spread. However, WHO’s latest update on the variant states that “current data do not indicate that this variant leads to more severe illness than other variants in circulation.”
WHO also noted that little information is available about the variant right now, and that these conclusions are drawn from preliminary observations.
The state health department echoed WHO, saying that there’s no evidence the variant poses significant risk to the public.
DOH noted that the case was detected in the airport, making it unclear whether or not the person who tested positive is a Washington resident.
“Because this is a Traveler Genomic Surveillance collection, the collection site would be SEA-TAC airport; however, that doesn’t mean that the case is necessarily a Washington resident, meaning county may not be a relevant field,” the DOH statement said.
COVID-19 cases in WA
COVID-19 case counts have fallen in Washington so far this year. Through mid-May, the state has seen 399 COVID-19 deaths, according to DOH’s respiratory illness dashboard. That’s less than half of the 897 deaths seen at this point last year, and around 25% of the number seen in 2023. The disease currently accounts for 0.5% of Washington hospital visits, compared to 0.9% last May and 1.5% in May of 2023.