Many people are worried that the rise of the delta variant of the coronavirus, which is more contagious than the earlier variants and has become the dominant strain in the U.S., as well as in Massachusetts.
Among the questions people have been wondering is whether they need to wear masks inside again indoors, even if they've been vaccinated. The World Health Organization recently said they should, but the U.S. Centers for Disease Control and Prevention says that's unnecessary.
Dr. Ashish Jha, dean of the Brown University School of Public Health, tackled that question this week in a Boston Globe opinion piece. The COVID expert said that the current stage of the pandemic requires localized health guidance based on how many people in a particular area have been vaccinated, since the vaccines are effective at stopping infections and, when that fails, serious complications.
"The evidence right now says if you live in a highly vaccinated community with low infection rates, fully vaccinated people can skip the mask if they are willing to tolerate a minuscule risk of a breakthrough infection," Jha wrote.
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He explained it using a sports analogy, comparing Massachusetts and its high rate of vaccination with Mississippi and its lower rate to hockey goalies who have to stop different amounts of shots.
"Being fully vaccinated is like getting a great hockey goalie … who blocks around 90 percent of attempts. In Massachusetts, there isn’t much virus around to even put a shot on target, and therefore little reason to wear a mask indoors. In Mississippi, there are simply many more shots on goal, and even a terrific goalie will occasionally let a shot in," Jha wrote.
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Other Massachusetts health experts asked about the delta variant and mask guidance by NBC10 Boston this week gave no indication that masks are necessary in the state, but encouraged people to continue wearing them if they prefer to.
"Since the U.S. vaccines are effective against the Delta variant, I see no reason why vaccinated individuals in Massachusetts should need to wear masks, unless they wish to for their own comfort," said Dr. Shira Doron, an infectious disease physician and epidemiologist at Tufts Medical Center.
But Dr. Davidson Hamer, a physician at Boston Medical Center, said he feels more comfortable wearing "a mask in indoor locations such as supermarkets, movie theaters and any other public place where there is a likelihood of close contact with other people."