The World Health Organization (WHO) is keeping an eye on a new COVID-19 variant called NB.1.8.1, or “Nimbus,” that has spread across Europe, the Americas and the Western Pacific.
Nimbus is a descendant of the Omicron variant of the virus and was first identified in late January.
Its spike mutations appear to make it more transmissible than other COVID-19 variants, according to the WHO. Spike mutations refer to changes in spike proteins, which sit on the surface of the virus and help it enter healthy cells.
While it is spreading in the U.S. and Canada, along with 20 other countries, it does not appear to be driving an increase in sickness or hospitalization.
In April, NB.1.8.1 sequences made up 10.7 percent of all submitted sequences from confirmed COVID infections, up from 2.5 percent a month earlier, according to a risk evaluation released by the WHO.
The WHO last month deemed NB.1.8.1 a variant “under monitoring.” Here’s what to know about the variant.
Where are cases in the US?
Most cases of COVID-19 in the U.S. still stem from the LP.8.1 strain, another Omicron descendant. But it looks like NB.1.8.1 might soon replace it as the more common strain, according to data from the Centers for Disease Control and Prevention (CDC).
The CDC estimates that 37 percent of COVID-19 cases in the U.S. stem from the NB.1.8.1 variant, while 38 percent are a result from an infection of the LP.8.1 strain of the disease. At the end of May, the agency estimated the NB.1.8.1 variant caused about 15 percent of all COVID-19 cases.
But the agency notes on its website that due to low numbers of virus sequences being reported, precision in the most recent reporting period is low.
The NB.1.8.1 variant has been found in at least 13 states, according to Today, which cited data from the Global Initiative on Sharing All Influenza Data (GISAID) database.
Those states are: California, New York, New Jersey, Maryland, Arizona, Illinois, Hawaii, Massachusetts, Ohio, Rhode Island, Vermont, Virginia and Washington.
The available data on “Nimbus” suggests it poses a low global threat and that existing COVID-19 vaccines provide adequate protection against severe illness and hospitalization, according to the WHO.
“Currently approved COVID-19 vaccines are expected to remain effective to this variant against symptomatic and severe disease,” the WHO’s risk evaluation reads. “Despite a concurrent increase in cases and hospitalizations in some countries where NB.1.8.1 is widespread, current data do not indicate that this variant leads to more severe illness than other variants in circulation.”
Lionel Gresh, an international consultant at the WHO, told The Hill that many new cases in Canada are likely linked to the NB.1.8.1 variant, but that there has not been any major changes in the country in terms of cases, hospitalizations, ICU admissions or deaths linked to COVID-19.
What are the symptoms?
Symptoms of NB.1.8.1 seem to be similar to those associated with other Omicron variants, according to Gresh.
Some common COVID-19 symptoms include cough, fever, fatigue, muscle aches, congestion, headache, nausea, vomiting, and a new loss of smell or taste, according to the CDC.
“We should be as concerned about [NB.1.8.1] as we are concerned for COVID in general,” Gresh said. “Not more, not less.”
Some recent COVID-19 patients have reported experiencing something called “razor blade throat,” according to Salon.
But it is unclear if that symptom is connected to one of the COVID variants or another respiratory illness circulating, Ryan Gregory, an evolutionary and genome biologist at the University of Guelph in Canada, told Salon.
