COVID-19 cases have jumped 59 percent in New England in the past 2 weeks

NEW Health holds a Pfizer Clinic at the Warren Prescott School in Charlestown.Barry Chin/Globe Staff

The Baker administration on Tuesday ordered Massachusetts hospitals, already teeming with patients who delayed care during the early days of the pandemic, to reduce nonurgent surgeries to help manage a potential winter rush of people sick with respiratory illnesses, including the flu and COVID-19.

The order comes as the coronavirus is again causing a surge of infections throughout New England with the onset of cold weather, with Massachusetts and Connecticut experiencing the steepest rise in cases in the country.

Over the past two weeks, the seven-day average of new cases has increased by 117 percent in Connecticut and 83 percent in Massachusetts. In Maine, cases are up by 34 percent, with Rhode Island and New Hampshire seeing slightly smaller increases. Vermont had the lowest, at 15 percent, according to the Centers for Disease Control and Prevention.

With vaccinations protecting a high percentage of the population in those states from the worst effects of COVID-19, some experts are hopeful that these cases will be less severe and less likely to stress the region’s already overburdened hospitals.

“I anticipate hospitalizations and deaths to be much, much lower this season than last season,” said Dr. Sten H. Vermund, dean of the Yale School of Public Health. “Overwhelmingly, serious disease is a phenomenon of unvaccinated people.”

Still, bracing for the worst, the Massachusetts Health & Hospitals Association agreed Tuesday to the Baker administration order to reduce procedures that are scheduled in advance because they are not an emergency, and delaying them will not result in adverse outcomes to the patient’s health — such as total knee and total hip replacements.

For all New England states combined, the seven-day average of daily new cases has doubled in less than a month. In just the past two weeks, the number is up 59 percent, reaching 5,442 cases per day, according to CDC data updated Monday.

On a per capita basis, case rates in every New England state except Connecticut are now above the national average, with New Hampshire more than twice as high — 65.0 cases per 100,000 residents — compared with the national average of 27.4 cases per 100,000.

The increases come after a spike in September in New England had appeared to be subsiding. With the weather turning colder, case numbers are rising across the country as well, and officials are calling on all adults to get boosters to shore up the waning immunity from their original shots.

Vermund said the increase is part of a seasonal surge in all respiratory viruses, such as the flu. “Coronaviruses and other respiratory viruses are happier in the cool, dry, indoor air,” Vermund said.

Some of the increase in cases may also reflect better availability of tests and greater awareness of the need to get tested even with minor symptoms, he said.

But many uncertainties remain.

“This is our first Delta winter,” said Dr. Nahid Bhadelia, founding director of the Boston University Center for Emerging Infectious Diseases Policy and Research. “We don’t know how Delta will behave.”

She was referring to the prevailing Delta variant of the coronavirus, which upended expectations of the pandemic’s course because it is much more contagious than previous variants. Even individuals who are vaccinated can contract and transmit the virus, although the window during which they can spread COVID is shorter, and they are far less likely than the unvaccinated to fall seriously ill and die.

The fact that so many people are vaccinated and COVID-19 treatments have improved may blunt the effects of any surge, Bhadelia said. But countervailing forces continue to sow uncertainty, she said, including waning immunity among some vaccinated people and clusters of unvaccinated people where severe surges can take root even in highly vaccinated states.

“I’m keeping my fingers crossed that we will see a disconnect between hospitalizations and infections,” Bhadelia said.

Dr. Eric Dickson, chief executive officer of UMass Memorial Health, said he’s already seeing concerning trends that could overwhelm hospitals. “We’re seeing an uptick in COVID cases. We’re seeing more breakthrough cases,” he said. He estimated that almost a third of hospitalized COVID-19 patients had been fully vaccinated.

For a variety of reasons, hospitals in Massachusetts are running about 15 percent above normal capacity, Dickson said. And 7 percent of hospitalized patients have COVID-19. That means COVID accounts for “about half the problem,” he said.

At UConnHealth in Farmington, Connecticut, hospital epidemiologist Dr. David B. Banach said that cases are milder, especially among vaccinated people.

“Hospitalization rates have not been increasing at the same rate as new cases. That provides good evidence that the vaccine is working,” he said.

That’s why he views a COVID-19 case right now differently from one in November 2020. “We’re not seeing the severe infections rise at the same rate,” Banach said.

Michael T. Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, said no one knows why cases are increasing in the Northeast.

“This is part of the mystery of the surges we see with COVID-19, why they start and why they stop — we don’t know,” he said. “We do know that vaccination and mitigation can reduce the impact of the surge.”

“There is less severe illness, less deaths,” he said. “At the same time, it points out the fact that this virus is still extracting a very large toll on us.”

“The vast majority of us are done with this pandemic,” Osterholm said. “The problem is, it’s not done with us.”

Connecticut Governor Ned Lamont, referencing a national map of new cases at a briefing Monday, said the current surge presented “a sort of mirror image” of where the country was in late summer, when cases were rising quickly in the South but were lower in New England.

This time, he said, the region is better prepared for a fresh COVID onslaught. “We’ve got the vaccine. We’ve got the boosters. We’ve got the masks. We’re going to get through this, no question about it. Let’s make sure that the next wave is the most mild of all,” said Lamont, whose state, despite its rapidly growing counts, still has the lowest infection rate on a per capita basis among New England states, at 20.7 cases per 100,000.

Officials have warned that unvaccinated people face much higher risks from COVID-19. The CDC says that, according to data collected from about two dozen US jurisdictions, unvaccinated people had 5.8 times the risk of contracting COVID-19 and 14 times the risk of dying from the disease.

Kevin Burns, a physician assistant who works in the emergency department at Yale New Haven Hospital, said that over the last couple of weeks, he’s been seeing at least two to three COVID-19 cases per shift. Before that, he said, “I could go a couple of weeks without seeing a COVID patient.”

“For the most part,” he added, “none of them have been critically ill.”

“We have been doing so well,” he said, referring to the low case rates in Connecticut. “It’s hard to see it rise back up again. You kind of hope you’ve seen the last surge. The thought of another one gives you a sense of dread for the winter.”