The new, more contagious COVID subvariant XBB.1.5 that's believed to be New England's most dominant strain of the virus has acquired a dramatic nickname: "the Kraken."
The alias was coined informally by scientists on Twitter in an attempt to help differentiate between the ever-changing variants. This particular omicron descendant could very well be contributing to a recent rise in COVID-19 wastewater levels and hospitalizations across Massachusetts, Boston-based infectious disease experts have said.
In the latest episode of NBC10 Boston's weekly "COVID Q&A" series, Tufts Medical Center's Dr. Shira Doron, Boston Medical Center's Dr. Sabrina Assoumou and Brigham and Women's Hospital's Dr. Daniel Kuritzkes explained whether we should worry about the subvariant, where the informal alias comes from and whether the fabled nickname is a form of fear mongering.
What is XBB.1.5?
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The variant is XBB.1.5, a highly contagious "recombinant" variant that spawned from two different BA.2 variants. It is related to the XBB variant, which was previously behind a COVID surge in Singapore.
Symptoms largely remain the same as earlier variants, experts say.
Since the variant is more contagious than many of its predecessors, it has quickly rose to predominance. Within the last two months, tracking numbers from the CDC showed the XBB.1.5 variant has climbed to now make up nearly 30% of cases in the U.S.
But here in New England, XBB.1.5 accounts for a whopping 71% of all COVID-19 cases. Only three weeks ago, XBB.1.5 accounted for only 11% of COVID cases in the region.
Doron emphasized, however, that the CDC's weekly variant data updates with what is referred to as a "nowcast," the agency's estimate based on patterns from previous weeks. The numbers are often readjusted later to reflect what has been learned in the meantime.
"The variant numbers in the CDC tracker are models. They are estimates and they aren't always right. And they may be subject to bias, especially during holiday times," Doron said.
While COVID levels have increased in the Greater Boston area over the last several weeks, Boston doctors aren't going so far as to call this a surge. And they aren't sounding the alarm over the latest subvariant.
"From my perspective, there's nothing surprising or uniquely different about the XBB variant than any preceding variant," Kuritzkes said. "Each subsequent variant is going to look different from the preceding variant and it's going to differ in ways that allow it to escape from immune control that had limited the spread of the previous variant. And this is what we should expect."
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Why is it being called 'the Kraken'?
Dr. Ryan Gregory, a biology professor at the University of Guelph in Ontario, Canada, said the nickname was simply "intended to help people keep track of who's who in the ever-growing variant soup."
In a tweet earlier this week, Gregory stressed the nickname was "informal." Previous variants have also been given nicknames like the "nightmare" or "scrabble" variants as the virus continually mutates.
The nickname brought out differing responses from the Boston doctors.
"I'm not exactly sure why we're making so much of this particular subvariant when we have seen this story many times since the original omicron wave," Doron said.
"The way I think about it is scientists having fun, right? It's not an official name," Assoumou said. "And I think that some scientists felt like, because those variants were different enough from, let's say, the initial omicron, that they wanted to actually name it. And so they started using mythology to sort of underscore that these were sort of different from other ones."
Doron emphasized her concerns about fearmongering that nicknames like "the Kraken" could incite.
"There are people who stand to benefit from fearmongering. And then amplified by the media — it's really causing harm. It's really harmful when the messaging about the risk is out of proportion to the true risk," Doron said. "And these nicknames are coming from individuals. They're getting amplified on social media by other similar-minded individuals and picked up by the media because it gets clicks when it's scary. And I don't think it's okay to do that."