ATLANTA - The World Health Organization says the COVID-19 vaccines alone will not stop community transmission of a new highly contagious strain of the coronavirus.
Friday, a WHO scientist urged people to wear masks and physically distance in public, even when outdoors.
This comes amid concerns about the new Delta variant, which surfaced in India in December of 2020, fueling a major outbreak in that country.
In England, where nearly half the population is fully vaccinated, the Delta variant is spreading quickly, especially in younger people, who have not yet had a chance to get vaccinated.
As vaccinations slow across the US, the Delta variant is quickly picking up steam.
It now makes up 20% of sequenced US cases.
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In the UK, the mutation is thought to be linked to at least 95% of infections, officials say.
Dr. Felipe Lobelo, director of epidemiology for Kaiser Permanente in Georgia, says the Delta variant is the most transmissible strain we have seen so far in this pandemic.
It is about 60% more transmissible than the previously dominant strain, known as the Alpha variant.
That strain was much more contagious than the original or "wild-type" virus.
"If you have contact with somebody that actually has COVID, you don't really need to be that close or spend too much time indoors," Dr. Lobelo says. "There have been reports in other countries where just a few seconds of close contact may put you at risk, because this variant is much more ‘sticky,’ it's much more transmissible."
An analysis by Public Health England showed the Pfizer-BioNTech are the AstraZeneca vaccine offered about 90% protection against severe COVID-19 and hospitalization.
The same study found a single dose of the two-dose vaccines offered just 35% protection against symptomatic infection.
In Georgia, 38% of residents are now fully vaccinated, while nationally 46% of Americans have received their full doses.
But, many Americans remain unvaccinated.
"So, I think, unfortunately, what we're going to see in the United States is localized outbreaks, particularly in those regions of the country or pockets of the population where the vaccination levels are not high enough," Dr. Lobelo says.
He is also concerned about African Americans, Hispanics and other minority groups, who have lower rates of vaccination.
The CDC says fully vaccinated people no longer need to wear masks or physically distance in most public settings.
Dr. Lobelo says he is not taking any chances with the Delta variant.
He says if he is indoors in public or around people he is not certain are vaccinated, he continues to wear a mask.
"I don't want to take risks, particularly because I have a 7-year-old at home," he says. "Even though I am at low risk, I don't want to be putting him at risk. So, we need to be doing this for the populations that have not been able to get vaccinated."
US experts say the number of cases tied to the variant is doubling about every 10-14 days.
At this rate, the Delta variant could be the dominant strain of the virus in the US later this summer.
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