One of fewer than a dozen cases of a potentially worrisome new COVID variant has been detected in Michigan following the discovery of cases in Denmark, Israel and the United Kingdom.

The U.S. Centers for Disease Control and Prevention announced Thursday it was tracking the variant, BA.2.86, after the University of Michigan lab detected a case among its COVID sequencing efforts. And the World Health Organization announced it had added the variant to its list of seven variants to monitor.

At the time, BA.2.86 had been detected in four cases globally.

The infected person from Washtenaw County is an older adult with mild symptoms and is not hospitalized, Chelsea Wuth, a Michigan health department spokesperson, told Bridge Michigan in an email.

Here’s what to know.

Should we worry?

It’s too soon to tell.

Some fear BA.2.86 has the potential to sicken and duck vaccine protection because it is genetically different from other variants of COVID-19.

In simplest terms, the genetic building blocks of its spike protein — the virus’ key to entering human cells — are significantly different from in previous versions of the virus.

That could be worrisome as cooler weather is looming that will send more people inside — and federal approval for the newly formulated COVID booster is not expected until October.

If few have the variant, what’s the issue?

Many more likely have the variant.

That BA.2.86 was detected in several countries suggests it has circulated undetected for some time, said Emily Toth Martin, part of the U-M effort to track COVID and other respiratory diseases.

The first swabs in the four cases were taken in July, although the samples weren’t fully genetically-sequenced and reported until earlier this month, she said.

“The fact that we’re having multiple countries report this (variant) as independent events about the same time means it’s probably already fairly widespread,” Toth Martin said.

Is COVID on the rise?

The identification of a new subvariant abroad and in Michigan comes as the state and nation report small increases in cases and hospitalizations from the virus and fewer deaths.

As of Friday, there are now 201 patients with COVID-19 in Michigan hospitals. That’s nearly double than earlier this month, but still near record lows and a fraction of the 5,000 in Michigan who were hospitalized in January 2022.

A year ago there were 1,289 COVID-19 patients in Michigan hospitals and 116 in intensive-care units. On Friday, just 13 COVID-19 patients required ICU care.

The state is also reporting far fewer deaths from COVID-19, with two this week and five last week. All told, there have been 39 confirmed COVID-19 deaths in July, compared to 411 in July 2022.

What if vaccines don’t work against it?

As with so much with the pandemic, much is unknown and time will tell.

At least one expert, Jesse Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Center in Seattle, suggests the genetic changes with BA.2.86 could mean it is short-lived, like most other coronavirus variations, unable to outpace the transmissibility of versions currently circulating.

But Bloom, who was clear to note that people are “completely within reason to ignore this variant right now,” also said the same changes could also make it able to dodge protection from current vaccines.

Even if that happens, it doesn’t mean that the world is back to Square 1 in the COVID fight, said Dr. Victor DiRita, chair of the department of microbiology and molecular genetics at Michigan State University.

Both vaccines and infections have built community-wide immunity to COVID after more than three years, said DiRita, who leads MSU’s COVID surveillance efforts in western Michigan and Flint.

“We don’t have to depend solely on the vaccine for our protection anymore,” DiRita said. “We’ve got a lot of different types of immunity just from having been infected.”

Bottom line: Will it make me sicker?

Stop us if you’ve heard this before: No one really knows.

The designation as a “variant under monitoring” by the World Health Organization simply means it’s “one to keep an eye on,” MSU’s DiRita said.

In fact, BA.2.86 could be an “attenuating” coronavirus, meaning infection caused by it will cause less severe disease than current versions, agreed Toth Martin.

“It’s just too early to tell,” she said.