Mass. coronavirus cases are ticking up again. Should you worry?

The more of these the better - a coronavirus vaccine being prepared at a clinic last month in MattapanPat Greenhouse/Globe Staff

Coronavirus case counts and other key metrics are ticking up again in Massachusetts, a distressing development in a state that has already endured massive disruption, illness, and loss of life from the pandemic. Will it be different this time around?

The seven-day average of confirmed coronavirus cases climbed to 161 on Thursday, up from a low point of 52 it had reached on June 28, according to Department of Public Health data. The seven-day average rate of positive tests has also been edging upward.

The numbers remain at extremely low levels compared with the state’s first surge in the spring of 2020 and second surge this past winter.

But the increases are consistent with a national rise seen as a result of the fast-spreading Delta variant, lagging vaccination rates, and Fourth of July.

They come after weeks of euphoria over pandemic numbers that were dropping and vaccination numbers that were rising — fueling hope that the pandemic might finally be crushed.

We asked experts to weigh in on the situation in highly vaccinated Massachusetts, including whether people should start taking precautions again. Here’s what they said.

How concerned should we be?

“Any increase in numbers of cases is of concern,” said Dr. Daniel Kuritzkes, chief of infectious diseases at Brigham and Women’s Hospital. But for now, the number of new cases is “still quite low,” he said.

And because most of the new cases are in otherwise healthy young adults, “It’s not yet having a huge impact on hospitalizations here in Massachusetts,” said Kuritzkes.

Dr. Philip Landrigan, director of the Global Public Health Program at Boston College, said it’s important to keep the uptick in perspective.

“Even though it’s real and even though it’s not good, the numbers are still incredibly down from where they were a few months ago,” he said — a fact he attributes “almost entirely” to the fact that Massachusetts is a national leader in vaccinations.

“The vaccine is highly effective and it’s effective even against the Delta variant,” Landrigan said. Both in Massachusetts and across the US, “virtually every case is occurring in somebody who’s not vaccinated.”

Dr. David Hamer, a physician at Boston Medical Center, said he was “worried” about the nationwide uptick: “This may be spreading into Massachusetts, so we need to increase our guard.”

Hamer said he feared the virus spreading both among the unvaccinated and the vaccinated.

Any time there is more virus circulating in the community, there are more opportunities for vaccinated individuals to become infected — a particular concern for those with weak immune systems, said Kuritzkes.

“I think we all have to be concerned until everybody is vaccinated and protected from this virus,” said Dr. Helen Boucher, interim dean of the Tufts University School of Medicine. “We’re not all safe until everyone is safe, not just here in Massachusetts but actually around the world.”

What about vaccinations?

All the experts agreed: vaccination remains crucial.

“People who are not vaccinated really must get vaccinated, both to protect themselves and to protect other people,” Landrigan said. Anyone who is unvaccinated is “gambling with their lives. They’re gambling with their parents lives. They’re gambling with their children’s lives.”

If they still choose not to get the shot, they “have to behave responsibly and not go into group settings where there’s the risk of spreading the disease,” Landrigan said. “Anybody who’s not vaccinated who goes into a group setting is just setting themselves up for disease and death.”

Boucher pointed to a recent study by the Commonwealth Fund, a nonprofit research group, that found that vaccinations have already prevented close to 280,000 deaths and up to 1.25 million hospitalizations in the United States.

What else should we do?

“I don’t think we need to be making any significant changes at this time — although obviously we need to keep a close eye on the numbers,” Kuritzkes said. “I think people who are fully vaccinated, unless they are immunocompromised, have every reason to believe that they are fully protected.”

Kuritzkes said shopping “is not a problem,” but recommended that individuals be “a little more conservative” at large indoor events, like concerts.

“Even if you’ve been vaccinated, you might want to think twice about going into an intensely crowded situation,” Landrigran agreed.

Hamer advised a more cautious approach: “People should wear masks at least as much as feasible in indoor settings,” he said.

Dr. Paul Sax, clinical director of infectious diseases at Brigham and Women’s, also said he and other specialists “have continued to wear masks in indoor public spaces, especially if crowded. This includes stores, supermarkets, and public transportation.”

As for dining, it’s a risk and “each person needs to make the decision for themselves,” he said. “People should remember that COVID is still very much with us.”

It’s summer. What about our vacations?

Landrigan said it’s fine for fully vaccinated families to head out on vacations — so long as case rates are low in their destinations.

”If they and their family are fully vaccinated, I would have no problem at all with them going to the Cape or any place in New England,” he said. “If they were going to go to Alabama, there’s going to be more risk because it’s just a lot more virus circulating around in most of the Southern states.”

Families with children under age 12 who have not been vaccinated, or individuals who are immunocompromised, should be extra cautious, he said.

”That person is going to be at some risk if they go to the South,” Landrigan said.

Will this be as bad as the last two times?

The impact of the uptick could be smaller because of the amount of people who have already been vaccinated, said Hamer.

“I think it could be less intense because I think there’s going to be reduced risk of more-severe disease and therefore hospitalization,” he explained.

Though there’s still a risk to vaccinated individuals, “the good level of vaccine coverage we have in the Commonwealth will mitigate the potential impact of a third wave,” Hamer said.

To Kuritzkes, the state’s numbers are actually proof that vaccines are working.

“The fact that we’re not seeing the kind of spread in Massachusetts that is being seen in other parts of the country — like in Missouri and Mississippi — is evidence of effective herd immunity,” Kuritzkes said.

“Overall, the message is that we’re doing well, but people can’t let down their guard,” Landrigan agreed.

“COVID has not gone away as much as we wish it would. That’s the message,” Boucher said. “The other message: it’s not too late to get your vaccine.”

Material from The Associated Press was used in this report.