A new variant of the SARS-CoV-2 coronavirus has put epidemiologists around the world on alert, and the World Health Organization is asking countries to sustain early warning, surveillance and reporting systems as it works to evaluate the current COVID-19 risk level.
The BA.2.86 variant, which was first detected in Israel, was designated a new variant under monitoring by the WHO on Aug. 17, after the agency received nine sequences from five countries — three in the WHO’s European Region, one in the African Region and one in the Region of the Americas.
The variant has more than 30 mutations in the spike protein compared with the XBB variants that are currently dominant in the U.S. and around the world, namely XBB.1.16 and EG.5, which has been dubbed Eris, following the Greek-alphabet designation used for other variants.
The WHO made EG.5 a variant of interest, or VOI, earlier this month, which is an upgrade from the designation of variant under monitoring, or VUM.
But BA.2.86 is worrying experts because there is too little data to assess its potential impact.
“It is crucial to sustain early warning, surveillance and reporting, variant
tracking, early clinical care provision, administration of vaccine boosters to high-risk groups, improvements in ventilation, and regular communication,” the agency said in its latest weekly update.
That update, which reviews the state of the virus for the 28-day period through Aug. 20, contains no data from the WHO’s Region of the Americas, as reports for the period were incomplete. That’s a worry that the WHO has consistently warned about as countries pull back on their monitoring of the illness as they seek to put the pandemic behind them.
The WHO officially declared the emergency phase of the pandemic to be over on May 5 but emphasized that COVID remains a major threat. Many countries have dismantled much of their systems of oversight and greatly reduced testing and data measurement.
See also: New ‘Eris’ COVID variant is dominant in the U.S., but a shortage of data is making it hard to track
The U.S. Centers for Disease Control and Prevention offered an update this week on BA.2.86 — which it said has been detected in Denmark, South Africa, Israel, the U.S. and the U.K. — and said the multiple locations are a sign of international transmission. The CDC acknowledged the surveillance challenge.
“Notably, the amount of genomic sequencing of SARS-CoV-2 globally has declined substantially from previous years, meaning more variants may emerge and spread undetected for longer periods of time,” the U.S. agency said in its update.
The CDC also noted a current increase in hospitalizations in the U.S., although it said that’s not likely driven by the BA.2.86 variant.
“It is too soon to know whether this variant might cause more severe illness compared with previous variants,” said the CDC.
Perhaps the bigger issue is whether the new variant has greater escape from existing immunity from vaccines and previous infections, compared with other recent variants.
“One analysis of mutations suggests the difference may be as large as or greater than that between BA.2 and XBB.1.5, which circulated nearly a year apart,” the CDC said. “However, virus samples are not yet broadly available for more reliable laboratory testing of antibodies, and it is too soon to know the real-world impacts on immunity.”
Americans gearing up for what’s expected to be an annual COVID vaccine booster this fall can be confident those vaccines will be designed to protect against all subvariants of XBB, including Eris, the agency said.
The CDC said it’s likely that antibodies built up in the population through infection, vaccination or both will provide protection against BA.2.86. However, it said, “this is an area of ongoing scientific investigation.”
Eric Topol, the chair of innovative medicine at Scripps Research in La Jolla, Calif., said the ability to neutralize the virus depends on the levels of neutralizing antibodies, and those are bound to be lower against BA.2.86 than earlier variants that people have been exposed to or immunized against.
“Also to note, the burden of new mutations for BA.2.86 is not confined to the spike and is seen broadly across other components of the virus,” he wrote in commentary this week. “If BA.2.86 takes off, it will be a real test of how good our T-cell response can rev up to meet the challenge.”
Meanwhile, the CDC’s weekly projections for where Eris and other variants are circulating continue to be hampered by a shortage of data. In early August, the CDC said it would unable to publish its “Nowcast” projections because it did not have enough sequences to update the estimates.
“Because Nowcast is modeled data, we need a certain number of sequences to accurately predict proportions in the present,” CDC representative Kathleen Conley told MarketWatch at the time.
The agency had received data from just three U.S. regions. In its most recent weekly update for the week through Aug. 19, it also got data from just three regions.
Separately, the CDC reported a 21.6% increase in U.S. hospitalizations for COVID in the week through Aug. 12. Deaths rose 21.4% in the week through Aug. 19.
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