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The study is in line with others from the US and around the world showing Delta's increased tendency to cause largely minor infections among fully vaccinated people.
As of Monday, the seven-day weighted average of positive tests in Massachusetts is 2.59%.
The move could boost vaccination efforts in the United States.
As of Thursday, the seven-day weighted average of positive tests in Massachusetts is 2.76%.
Dr. Mallika Marshall answers your coronavirus questions.
The plan is to start administering those third doses the week of September 20 but not everyone will be eligible at once.
The Massachusetts Department of Public Health reported 1,452 new confirmed COVID cases and 11 additional deaths in the state on Wednesday.
Booster doses of Pfizer and Moderna's COVID-19 vaccine will be offered late next month, beginning with those vaccinated first, like health care providers.
The Massachusetts Department of Public Health reported 1,254 new confirmed COVID cases and six additional deaths in the state on Tuesday.
More than half of the counties in Massachusetts are now at a high risk for COVID-19, according to the Centers for Disease Control and Prevention.
A group of cities and towns located south of Boston have higher positivity rates for coronavirus than the state average.
As of Friday, the seven-day weighted average of positive tests in Massachusetts is 2.89%.
The FDA has authorized a booster shot for immunocompromised people for whom two doses of the COVID-19 vaccine might not be enough protection.
Moderna's Covid-19 vaccine protects people for at least six months and likely longer -- even against new variants, researchers reported Thursday.
Acting Boston Mayor Kim Janey announced on Thursday that all city employees will be required to be vaccinated against COVID-19 or submit to regular testing for the virus.
In a first interview since his ex-wife's murder trial, Patrick Clancy describes what happened at home before his children were killed and how he handled his grief.
Patrick Clancy speaks about his ex-wife Lindsay's trial, his grief and moving forward while facing intense public scrutiny.
The New England Patriots' defense smothered Aaron Rodgers on the way to a 20-3 victory over the Pittsburgh Steelers on Sunday.
Patriots quarterback Drake Maye and head coach Mike Vrabel were asked about the team's offensive struggles after a 20-3 win over Pittsburgh Sunday.
The Red Sox were 32-46 and 15 1/2 games back in the AL East race on June 24. They have since gone 52-25 and will be in the playoffs.
Last year, insurance companies in Massachusetts said they would stop covering GLP-1s when used specifically for weight loss.
In Massachusetts, one high school explained steps it has taken to try and reduce head injuries.
This year, ER visits for tick bites have increased dramatically, corresponding with a new threat: a rise in Alpha-gal syndrome (AGS), where one bite from a lone star tick can make you violently allergic to red meat. How can you best avoid tick bites?
Moderna and Merck announced study results that reflect a "landmark moment" in treatment for one of the deadliest forms of skin cancer.
Sydney Towle, known for her social media content about living with a rare form of cancer called cholangiocarcinoma, died Wednesday in Bethesda, Maryland.
A former FAA special agent says the 9/11 attacks never should have happened because the government was aware of the vulnerabilities.
According to I-Team sources, a Massachusetts State Police trooper allegedly targeted his former girlfriend with racist messages after she began dating a man of color.
Massachusetts State Police have opened an internal affairs investigation after an alleged sexual assault at the department's Oak Bluffs barracks, the WBZ-TV I-Team has learned.
After a man sold his pickup truck on eBay he said the company held onto half his money - nearly $12,000. Here's how it was resolved.
A windshield replacement error knocked out the safety features in Meg Burke's car. When she paid nearly $500 to get it fixed, she couldn't get Safelite to pay her back, so she called the I-Team's Call for Action.
Jon Keller said it's a mistake to think that young people will automatically gravitate to a younger candidate in Massachusetts.
Barney Frank, a Democrat who represented Massachusetts in Congress for 32 years, has died. He was 86 years old.
Both the Trump and Healey administrations are using government websites to blame each other for the shutdown.
Which party stands to take more of the blame from voters for the government shutdown? Here's what a new poll says.
A UNH Survey Center/Granite State poll shows John Sununu crushing Scott Brown by 23 points among likely primary voters in New Hampshire.
The immersive WNDR Museum in Boston's Downtown Crossing is set to close down just two years after it opened.
Panera Bread is moving its headquarters from St. Louis to Weston, Massachusetts.
Breaking Grounds Cafe, a Peabody, Massachusetts coffee shop known for employing people with disabilities, is closing.
The buildings that house the Somerville Theatre and the Capitol Theatre in Arlington, Massachusetts are for sale.
Golden Temple and Party Favors in Brookline are closing after a combined 100 years in business.
Beauport, the Sleeper-McCann House has become one of New England's most imaginative seaside estates.
Blending clean modern lines with the warmth of a classic seaside retreat, this stunning North Shore coastal home was designed to feel both elevated and inviting.
Set across thirty acres of rolling lawns, wooded trails, and contemporary outdoor art, deCordova Sculpture Park and Museum invites visitors to experience art in the landscape.
James Beard Award-winning chef and restaurateur Karen Akunowicz has become known for her bold, Italian-inspired cooking and unmistakable culinary voice.
Just a short drive from Newport, the Norman Bird Sanctuary spans 300 acres of fields, forests, and coastal trails with sweeping views and more than six miles of hiking paths.
The New England Patriots' defense smothered Aaron Rodgers on the way to a 20-3 victory over the Pittsburgh Steelers on Sunday.
The Red Sox were 32-46 and 15 1/2 games back in the AL East race on June 24. They have since gone 52-25 and will be in the playoffs.
Despite the loss, the Boston Red Sox secured a playoff berth when the Houston Astros lost to the Atlanta Braves.
Betting platforms FanDuel and DraftKings say tools are there to help addicted gamblers slow down.
Kickoff between the Patriots and Steelers today is set for 1 p.m. at Gillette Stadium in Foxboro, Massachusetts. Here's how to watch.
A two-headed turtle on Cape Cod has veterinarians seeing double.
Video of a "birdnado" shows thousands of tree swallows preparing to migrate south in Newburyport, Massachusetts.
A magazine borrowed from the Concord Public Library in New Hampshire 132 years ago has finally been returned.
A blue marlin weighing 1,260 pounds was caught by a charter fishing boat off Massachusetts.
Natick says it is installing a new floating boardwalk across Pickerel Pond.
