BOSTON — Massachusetts has one of the highest vaccination rates for COVID-19 in the country, but the state still needs to get more shots into people's arms to achieve "herd immunity."
On Monday, Gov. Charlie Baker unveiled a new strategy aimed at expanding vaccination to reach the homeless, migrant workers, communities of color and other hard-to-reach populations that health officials say have been reluctant to get vaccinated.
The changes involve ramping down several mass-vaccination sites in the next month — including at the DoubleTree Hotel in Danvers — and diverting more shots to regional and local sites, mobile vaccination clinics and community centers.
"By bringing the vaccine to where people are ... we hope to make this process more convenient and accessible, and continue to add to the count of those who are already vaccinated," Baker said at a Monday briefing. "As we transition to this new phase, we're confident that we'll be able find more ways to offer vaccines to everyone who wants one through a smaller and more targeted approach."
More than 2.6 million people in Massachusetts — 37% of the population — are fully vaccinated. Another 1.2 million people in Massachusetts have had a first dose of the Pfizer, Moderna or Johnson & Johnson vaccines.
Baker said thousands of people still haven't registered to get their shots, even though they became eligible in recent weeks. He said as of Monday there are open appointments "everywhere."
"There's no more waiting or waking up in the middle of the night to book an appointment" he said. "This is obviously a welcome change from a few months ago when demand was exceedingly high and supply was not."
As of April 19, anyone 16 and older could make an appointment to get vaccinated.
Despite setbacks in its initial rollout, Massachusetts has become one of the top vaccinated states per capita. More than 7.3 million doses have been shipped to Massachusetts, of which nearly 85% have been administered, according to the state Department of Public Health.
Baker said the state is on track to meet its goal of vaccinating at least 4.1 million people by the end of June, which he called "an incredible achievement."
Herd immunity is the point where enough people are vaccinated to protect everyone from the spread of COVID-19, and the threshold depends upon the disease. Though the level needed to stop the spread of COVID-19 is unknown, public health experts estimate it could happen when 70% to 90% of the population is fully vaccinated.
Dr. Paul Biddinger, chief of Massachusetts General Hospital's Division of Emergency Preparedness and director of its Center for Disaster Medicine, said research tracking the distribution of the three vaccines confirm they are effective.
"We now have data from more than 150 million people which continues to show the safety and efficacy of these vaccines," he said Monday.
Nationally, about 147 million people — 44% of the population — have rolled up their sleeves for a vaccine dose, and 104 million are now fully vaccinated.
President Joe Biden is also trying to sell the vaccine to skeptics. The White House has launched a new campaign to battle vaccine hesitancy as it ramps up supply of the drugs and expands the eligibility pool.
Recent polls show about 30% of the U.S. population is still reluctant to get vaccinated.
Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at email@example.com.