Disease trackers say it’s safe for vaccinated people to sample new freedom, but ‘things can change on a dime’

Most vaccinated people are safe to go mask-free, they say, for now.

Masks remain a common sight, as seen at Faneuil Hall the day the state’s restrictions were lifted. Different areas of the state have widely varying vaccination rates.Jonathan Wiggs/Globe Staff

A few weeks ago, some feared that Governor Charlie Baker was lifting COVID-19 restrictions too soon. But now disease trackers say that Massachusetts appears to be in a good position to hold the deadly coronavirus at bay — and for most fully vaccinated people to return to their normal lives.

In the first week since most state restrictions were lifted, Massachusetts is reporting near-record low numbers of new infections, and more than half of residents are fully vaccinated. Those promising trends are emerging as the state heads into a season where people are more likely to be outside, where fresh, circulating air makes it less likely to breathe in aerosols from someone who is infected.

“At this point we are in nice weather and there is no evidence to suggest we have problematic” new strains of the virus in Massachusetts, said Dr. Joshua Barocas, an infectious diseases specialist at Boston Medical Center. “We also have one of the highest vaccination rates in the whole country, so it’s probably fine for now” for vaccinated people to go about their lives mask-free.

But Barocas and others caution that people shouldn’t get complacent: the virus roared back last fall after a deep summertime drop in cases. And huge swaths of the world remain unvaccinated, increasing the risk that a new strain of the virus could develop just as more places are opening up and travel increases. Today’s vaccines have provided remarkable protection so far, but it’s unclear if they will continue to be effective against future variants, he said.

At the same time, public health leaders warn that significantly lower vaccination rates in communities of color, along with higher numbers of infections, have left people in some pockets of the state far more vulnerable than others.

Barocas, who is vaccinated, said he would feel comfortable eating in a restaurant, as well as walking around without a mask. But he and other physicians noted that millions of Americans with a compromised immune system may still be at risk for serious complications from COVID, despite being vaccinated, and will need to continue taking precautions.

“For everybody else, it’s a matter of calculation,” Barocas said. “If you are vaccinated, it’s unlikely you will get sick, and even if you do, it’s very unlikely you will get very sick and die.”

As of May 24, there have been just 3,343 reported “breakthrough” instances of people in Massachusetts testing positive for the virus out of more than 2.9 million fully vaccinated individuals, according to state data. That translates to a breakthrough infection rate of 0.11% of all fully vaccinated people. Very few of those breakthrough infections make people seriously ill, and emerging science suggests the amount of virus they’re carrying is likely not enough to infect others.

Massachusetts closed out May with a seven-day average of 158 new confirmed COVID cases on Monday, state data show — about a third of the number from the same day a year ago. And the percentage of all tests coming back positive has also plunged during that time, from over 8 percent to now below 1 percent.

Baker was bullish about the state’s progress at a briefing on Wednesday, saying, “Here in Massachusetts, we have watched week over week over the course of the past five months, as the more people got vaccinated . . . the fewer people got sick, the fewer people got hospitalized, and the fewer people passed away.”

Disease trackers say it’s safe for vaccinated people to sample the new freedom that comes from the end of the mask mandate and most other limits on business and social interaction.

“Go to your favorite restaurant, but eat outside if you are still concerned,” said Dr. Daniel McQuillen, a senior physician of infectious diseases at Beth Israel Lahey Health and president-elect of the Infectious Diseases Society of America. “I don’t think it’s enough of a concern to be afraid of interacting with people if you are vaccinated. You can always wear masks inside if you wanted to.”

The concerns are more stark in many of the state’s communities of color. The state’s data show that 61 percent of white residents had received at least one dose of vaccine as of June 1, compared to just 45 percent of Black residents and 43 percent of Hispanic people.

Similarly, reported COVID infection rates are roughly three times higher for Hispanic residents and 1½ times higher among Black residents, compared to those who are white, state data show.

“The [Baker administration’s] focus is on overall population and it’s masking the inequities and burden that this places on low wage workers and workers of color who have not had the access to vaccines that wealthier white people have,” said Carlene Pavlos, executive director of the Massachusetts Public Health Association.

“Given that we are dealing with these kinds of gaps,” Pavlos continued, “it’s not safe . . . to have mask mandates so summarily go away.” She said the mandate should have been maintained until the significant disparities have eased, placing the onus on the state to achieve greater vaccination equity.

Even though the overall number of vaccinated people continues to rise, infectious disease experts say there may still be a rise in COVID-19 cases in the fall, similar to other respiratory viruses as more people move indoors, but that increase is likely to be far less dramatic than last autumn’s surge.

“The coronavirus may come back to some extent, but not in the levels we had seen,” said Brooke Nichols, assistant professor of global health at Boston University School of Public Health.

Despite the encouraging trends, infectious disease experts say now is not the time to be less vigilant. Already, the number of tests in Massachusetts and many other places has declined significantly as more people have been vaccinated. Disease trackers say that states will need to maintain some level of screening and more scrutiny of the genetic makeup of cases, known as genomic sequencing, so the country is not caught off guard by new strains of the virus that may prove more dangerous, despite vaccinations.

“If nothing else, this pandemic has shown us how quickly [a virus] can envelop the world if you are not paying attention,” said McQuillen, from Beth Israel Lahey Health.

Barocas, the infectious disease specialist at Boston Medical Center, said he’s concerned that the public focus has been so trained on getting back to normal that discussions about backup plans if the virus surges again have gotten short shrift.

“It looks really good right now in Massachusetts but things can change on a dime,” Barocas said. “And we need to have a contingency plan, a return to abnormalcy plan.”