Updated Dec. 21 at 1:04 p.m.
Well, that didn't take long.
Omicron is the dominant variant of COVID-19 in Massachusetts, according to new research from The Broad Institute of MIT and Harvard.
More Local News
Researchers determined that 45% of more than 1,100 positive tests taken around the state between Dec. 13-16 were the omicron variant by using a novel method for distinguishing between COVID-19 variants. They are confident it has crossed 50% since then.
"We estimate that, in fact, omicron became the most prevalent, the dominant lineage across Massachusetts on December 17th, on Friday," said Bronwyn MacInnis, director of pathogen genomics surveillance at the Broad Institute. "And if we extend even further, we assume that that percentage has continued to grow over the weekend and into [Monday]."
The announcement is consistent with what's been seen nationally, as the CDC reported Monday that the highly transmissible omicron variant is now the dominant COVID-19 strain in the country, making up 73% of new infections last week.
A graph showing the percentage of omicron cases in the state shows a staggering increase over the last week.
"I wouldn't say that it was terribly surprising," MacInnis said of their findings in Massachusetts. "Based on some data that we were seeing about the explosive rate of growth of omicron in other areas, in Europe and the U.K. and in South Africa, but also some smaller scale data sets coming out of particular communities [like] hospitals and colleges in Massachusetts and New England, we had a sense that Massachusetts broadly was on a similar trajectory."
The Broad Institute conducts genomic sequencing on positive COVID-19 tests in partnership with the state to determine what variants are present. But MacInnis said that process is slow, leading to the innovation that produced this latest data.
"Because omicron is moving so quickly and growing so quickly, the reality is that even though we really pulled out all the stops to do the sequencing as quickly as we can, and have gotten the turnaround time down to about seven days, it just wasn't fast enough for the speed of this virus," she said.
The new method, developed by Harvard graduate student Nicole Welch, uses a process called mCARMEN, which is based on the revolutionary CRISPR gene-editing technology.
"We're able to take a fine lens scope into the different mutations of interest and get an idea of which mutation is present," Welch said. "And this is different than what is currently being tested for."
Importantly, it provides same-day results. Welch said this technology could ultimately be used as a diagnostic tool to help hospitals identify which variant a patient has. That would be especially valuable for doctors, since omicron has been found to be less responsive to certain therapies than other variants.
The omicron news out of the Broad Institute comes as a new analysis of data released Monday by Massachusetts Department of Public Health shows that about 97% of COVID-19 infections in people who are fully vaccinated do not result in hospitalization or death.
“Vaccination continues to be the most effective tool we have against omicron and all COVID-19 variants,” acting DPH Commissioner Margret Cooke said in a written statement. “The data indicates that fully vaccinated and boosted individuals are well protected from severe outcomes of COVID-19, including hospitalization and death, and the Department of Public Health strongly urges all residents to get vaccinated and, when appropriate, get a booster.”
The new state data underscore the protection that booster shots have offered so far, with unvaccinated people 31 times more likely to get infected than those who got a booster.
Still, some public health experts are warning that the omicron variant could cause cases skyrocket to the point that even a low percentage of severe outcomes in vaccinated people will create some alarming numbers.
"One of the things I worry about is that I think out of a desire to be hopeful about what could be happening, I think people are anchoring on a possible decrease in the severity of omicron," said Dr. Paul Biddinger, chief preparedness and continuity officer for Mass General Brigham and a member of Gov. Charlie Baker’s medical advisory committee for COVID-19. "But it still absolutely causes severe illness. It puts people in the ICU. It is deadly. And so even a slight decrease, though it's a good thing, does not mean that Omicron is not a very serious virus to worry about."
Biddinger likened vaccines, and especially booster shots, to wearing a seatbelt.
"Unfortunately, of course, tragically, people do die in car accidents. But it's much less likely you're going to die if you're wearing a seatbelt," he said. "That doesn't mean seatbelts don't work. It means we should keep wearing them and using them all the time. It's exactly the same analogy for the vaccinations."
Correction: A previous version of this article misspelled Bronwyn MacInnis’ name as McInnis. That has been corrected.
