New guidance around the rapidly-spreading Delta COVID-19 strain and mask wearing is getting mixed reviews and causing confusion.
The World Health Organization is calling for masks again, despite the Centers for Disease Control and Prevention's latest guidance.
The recommendation comes as concerns over the COVID-19 Delta variant are growing.
This is creating confusion as new data emerges suggesting that vaccines protect against the variant. One study showed mRNA vaccines may provide protection for years with some exceptions.
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The World Health Organization on Friday urged fully vaccinated people to continue to wear masks, social distance and practice other COVID-19 pandemic safety measures as the delta variant spreads rapidly, CNBC reported.
And on Monday, the Los Angeles County Health Department said it "strongly recommends everyone, regardless of vaccination status, wear masks indoors in public places as a precautionary measure" due to the spread of the delta variant.
It's something that contradicts the most recent CDC guidance, which said vaccinated residents no longer need to wear masks indoors.
The mixed signals have some concerned.
"Implementing a mask mandate in the absence of no broader spread of the virus is likely to erode the ability to implement these kinds of measures when we need them," said Dr. Scott Gottlieb, former Food and Drug Administration Commissioner. "We need to give the public a breather."
The highly contagious Delta variant is gaining ground every day here in the U.S. -- more than doubling in cases every two weeks.
In Massachusetts, the Delta variant has been "steadily rising" since it was first clearly found in the state during the second week of April, said Boston Medical Center's Dr. Davidson Hamer.
As of early June, the variant accounted for about 7% of positive samples that have been sequenced in Massachusetts, according to GISAID.
More than 150 cases of the Delta variant were identified between March 13 and May 23, according to the Massachusetts Department of Public Health, which referenced data provided by U.S. Centers for Disease Control and Prevention from the national laboratories.