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What to know about the delta variant
Experts say the delta variant spreads more easily because of mutations that make it better at latching onto cells in our bodies.
As the delta variant continues to spread in countries around the world, some COVID-19 safety restrictions have been reinstated in efforts to curb the rising cases. But the director of the U.S. Centers for Disease Control and Prevention stood by the agency’s current guidelines Wednesday.
Several countries are now on the defense against the variant, which is considered by government scientists to be between 40% to 80% more transmissible than the previous dominant strain.
In some provinces of Thailand, a ban on indoor dining and gatherings of more than 20 people was announced. Israel reinstated an indoor mask mandate, and officials in Los Angeles County are strongly recommending the same. More than 1 million people in Sydney again went into lockdown this weekend. And the variant is responsible for 90% of all new infections in the U.K., which just recorded the most new coronavirus infections since early February.
The World Health Organization has also urged vaccinated people around the world to "be appropriately cautious" when it comes to transmitting the virus. Some WHO officials even urged those who have been vaccinated to "play it safe" and continue wearing masks.
RELATED: Delta variant: WHO urges vaccinated people to still wear masks, distance
Meanwhile, in the United States, the CDC has said those who are fully vaccinated, which is two weeks after your final shot, can resume activities that they did prior to the pandemic without wearing a mask or physically distancing unless it’s required in your area by state or local law.
And as precautions continue to take effect in the rest of the world, director Dr. Rochelle Walensky stood by the CDC’s guidelines Wednesday.
She said the CDC is leaving it up to local officials to set guidelines for mask-wearing.
Walensky said on NBC’s "Today" show that "we’ve always said that local policymakers need to make policies for their local environment," but added CDC guidelines broadly indicate those who are vaccinated don’t need to wear masks.
She also told ABC’s "Good Morning America" the "context in which the WHO is making recommendations is very different than us here in the United States" since less than 15% of the world is vaccinated.
As for the recommendation by officials in Los Angeles County, Walensky said "we are still seeing an uptick in cases in areas of low vaccination and in that situation, we are suggesting that policies be made at the local level."
WASHINGTON, DC - MAY 19: Centers for Disease Control and Prevention Director Dr. Rochelle Walensky is seen during a Senate Appropriations Subcommittee hearing to examine the FY 2022 budget request for the Centers for Disease Control and Prevention on …
RELATED: Fauci predicts regional spikes this fall if COVID-19 vaccination rate doesn’t go up
Earlier this month, Dr. Anthony Fauci, the country’s top infectious disease expert, said he believed regionalized areas will see spikes of COVID-19 depending on vaccination rates, but that the country likely won’t see another "wave" of infections and hospitalizations.
"I don’t think even under these circumstances that you’re going to see things like a thousand deaths a day," he said. "But there is a real danger that if there is a persistence of recalcitrance to getting vaccinated that you could see localized surges, which is the reason I want to emphasize what all four of us (on the White House task force) have said - all of that is totally and completely avoidable by getting vaccinated."
Americans at the highest risk for complications from COVID-19 are overwhelmingly vaccinated, according to CDC data, but only 53% aged 25-39 have received one dose. Among those 18-24, it's 47%.
The Biden administration is now focusing messaging for their trailing vaccination campaign on some 55 million unvaccinated adults, many of them under 30.
The administration has acknowledged that it will fall short of its goal of having 70% of adults vaccinated by July Fourth.
At this point, about 170 million American adults have received at least one vaccine dose, representing roughly two-thirds of those 18 and older.
RELATED: As delta variant rises globally, US targeting younger adults for vaccines
The potent delta variant that first ravaged India this spring and has now spread to at least 85 other countries.
The B.1.617.2 strain already accounts for more than 20% of new COVID-19 infections in the U.S., doubling in just two weeks, the CDC said last week.
Studies have shown that the available vaccines work against variants, including the delta variant.
This story was reported from Detroit. The Associated Press contributed.