A new Covid variant called HV.1 has replaced the EG.5 strain in the US, becoming the country’s most prevalent last week, according to data released by the US Centres for Disease Control and Prevention (CDC).
The two variants are genetically similar versions of Omicron, which is the most dominant in the country, but relatively few people have thus far had the new shots that could offer some protection against it.
NBC reports that HV.1 comprises around 25% of Covid cases now, up from around 1% at the beginning of August. EG.5, meanwhile, represents nearly 22% of cases, down from 24% at the start of the month.
Both are descendants of the XBB variant. The updated Covid vaccines from Pfizer and Moderna, which became available last month, target a different XBB descendant, called XBB.1.5.
But disease experts say the new shots should offer cross-protection against the currently dominant strains, and while not a “perfect match” for HV.1, “it’s still a good match because it’s still within the same family of variant”.
However, only about 3.5 % of the US population – around 12m people – have received the new Covid jabs since they became available in mid-September, a CDC spokesperson said.
Frustrations over rollout
In the current roll-out, public and private insurers are responsible for the cost of the shot, and healthcare and pharmacy networks place their own orders.
That has given rise to new challenges, including insurance issues, shipment delays and appointment cancellations.
Though most insurers agreed to cover the new Covid vaccines in full, some didn’t update their billing systems in time for people's appointments. As a result, patients were told they needed to pay for their shots, prompting some to cancel their scheduled vaccinations.
Delayed vaccine shipments also forced some pharmacies to cancel appointments last month. And parents have reported difficulty finding appointments for children, who require smaller doses.
Dr Scott Roberts, an infectious disease specialist at Yale Medicine, said some paediatricians’ offices may not be equipped to provide cold storage for the shots or lack freezer space. Others may have underestimated demand or been unwilling to pay for large shipments, he said.
Experts worry that people who hit roadblocks will stop trying to get vaccinated, and though Covid transmission seems to be slowing right now, Roberts cautioned that the virus was still making people severely ill.
“We have patients today in our hospital who are on mechanical ventilators,” he said. “We definitely need to push to get the high-risk people vaccinated.”
Since Omicron took over in December 2021, all dominant variants have descended from it. Scientists expect the virus to continue to evolve in this way, and for the most part, aren’t concerned about versions resembling similar ones seen before.
NBC News article – New Covid variant becomes dominant (Open access)
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