Public health experts in Massachusetts Sunday cautioned that holiday plans could be upended by the presence of the Omicron variant, as researchers race to evaluate the risk — and the effectiveness of current vaccines to combat the threat.
Both the World Health Organization and the US Centers for Disease Control and Prevention have called Omicron a “variant of concern.” On Saturday, Massachusetts reported its first case involving Omicron, and officials urged people to protect themselves by getting vaccine shots, masking up, and following pandemic guidelines.
Governor Charlie Baker said late Sunday afternoon at a public event that the state is working to expand its capacity to administer vaccines and open more clinics in local communities for people to get shots. And he emphasized the importance of vaccinations and booster shots.
“The biggest thing I would say to everybody is if you got vaccinated, and you’re eligible for a booster, go get one,” Baker said, who received his booster Friday. “If you haven’t gotten vaccinated, get vaccinated.”
Omicron’s timing — appearing as cold weather arrives, schools are in session, and people are planning holiday festivities — has officials urging people to watch for developments and stay flexible about the holidays.
“Keep your eye on the data and be prepared to change your plans if this virus turns out to be worse than those that came before it,” said Dr. Philip J. Landrigan, the director of Boston College’s global public health program, in an interview Sunday.
“People need to be very careful,” he said.
Dr. Robert Horsburgh, a Boston University professor of epidemiology, said that while the presence of Omicron could mean cutting back on holiday plans, people should not get discouraged.
It’s likely that existing vaccines will offer at least some protection against Omicron, he said, and small gatherings among vaccinated family members should be OK.
“If people’s holiday plans were to bring a lot of people together from all over the country, yes, they should be rethinking them,’ Horsburgh said. “If their holiday plans are to have a small dinner with their families, no, they don’t need to rethink them.”
On Sunday morning, Dr. Rochelle Walensky, director of the CDC, told ABC’s “This Week” that Omicron has been identified in about 15 states, and has caused several dozen cases nationwide.
She said she expects those numbers to increase as many of Omicron’s mutations are associated with more transmissible variants.
“What we don’t yet know is how [much more] transmissible it will be, how well our vaccines will work, whether it will lead to more severe disease,” Walensky told ABC’s Martha Raddatz.
Dr. Anthony Fauci, President Biden’s chief medical adviser, said on CNN’s “State of the Union” that early data indicates Omicron is not as dangerous as the Delta variant, which accounts for nearly all cases in the United States.
“But we have really got to be careful before we make any determinations that it is less severe or it really doesn’t cause any severe illness, comparable to Delta,” Fauci said.
Biden has said his winter COVID-19 strategy doesn’t include lockdowns and is focused on getting more people vaccinated. It also calls for a widespread testing program. More than 40 million American adults are unvaccinated, according to the Associated Press.
Baker, who spoke to reporters late Sunday afternoon at a Copley Square menorah lighting ceremony, said the state has been working with federal officials about the new variant.
The governor said he hoped and anticipated that the Biden administration’s decision to move forward with an aggressive rapid-test distribution program will help make it easier for people to get tested.
He said state officials have also discussed expanding the capacity to administer booster shot vaccinations, he said.
There are no supply problems for vaccines, he said, but the challenge is creating more sites for people to get the shots.
On Friday, he said that he and Lieutenant Governor Karyn Polito were on a call with local officials about opening clinics in their communities.
“The good news there was, just on the course of that call, we had about a dozen communities that stepped right up and said, ‘Yeah, we’d be happy to set up clinics,’ " Baker said. “And we’re hoping that process will continue going forward.”
So far, just two Omicron cases have emerged in New England, though more are expected. Connecticut reported a case Saturday, as did Massachusetts. In both cases, the people infected had been fully vaccinated.
Governor Ned Lamont of Connecticut said in a statement Saturday, that a man in his 60s from Hartford County manifested mild symptoms on Nov. 27. after a family member attended the Anime NYC 2021 convention at the Javits Center in New York City over the period of Nov. 17 to Nov. 22.
“We have life-saving tools like vaccines and boosters available to fight this pandemic— including the Delta and Omicron variants — and I urge everyone to take the necessary precautions to protect themselves and everyone around them,” Lamont said in the statement.
In Massachusetts, a woman in her 20s from Middlesex County who had traveled out of state developed mild symptoms and is recovering at home, according to Kate Reilly, a spokeswoman for the Massachusetts Executive Office of Health and Human Services.
Despite the need for caution, there are some encouraging differences from a year ago. More than 80 percent of residents have received at least one dose of vaccine, schools are open, and most pandemic restrictions have been eased.
But worrisome trends remain: Progress on new vaccinations has slowed since the spring (though there has been an uptick in recent weeks). Numbers of new cases have spiked, including those among students and staff in public schools. Hospitalizations have climbed.
The death toll hasn’t seen a similar spike, though COVID-19 remains a killer. On Friday, the state reported 27 new coronavirus deaths, bringing the total number since the pandemic began to 19,074.
Dr. Paul Sax, clinical director of the Division of Infectious Diseases at Brigham and Women’s Hospital, said he strongly suggests people attending a holiday gathering do rapid home testing the day of the event and limit the get-together to vaccinated people. He also recommended improving ventilation in a home, even if it’s just opening windows.
“Many may wish to forego large holiday parties, especially if they are immunocompromised,” he said.
But the highest-risk activities for COVID-19 remain the same, he said, including indoor dining, bars, parties, gyms, and places of worship, which are made riskier with crowds and poor ventilation.
“Case numbers have been high in MA since the late summer, and are higher now,” Sax said in an e-mail. “Masking during indoor public activities (shopping, concerts, plays, movies) made sense before Omicron, and still makes sense with this new variant.”
Sax said dining indoors at a restaurant is a personal decision, though people should consider their age, vaccination status, and medical co-morbidities as they consider whether to risk it, Sax said.
Landrigan noted that the state has reasonably strong pandemic measures in place and people need to follow that guidance. They should also be ready to make changes quickly to holiday plans until more is known about Omicron.
“People want to be careful about large gatherings, they want to be responsible about wearing masks and keeping social distancing, and just be a little patient until we have some clarity on what is going on here,” he said.
John Hilliard can be reached at firstname.lastname@example.org. Gal Tziperman Lotan is a former Globe staff member.