Do the vaccinated need masks as Delta variant spreads? What experts say of WHO advice
The COVID-19 vaccines will never be perfect; fully vaccinated people can still get infected, though they’re much less likely to be hospitalized or die from the disease. Yet, the Delta coronavirus variant first discovered in India has some experts concerned.
The World Health Organization suggested on Friday that fully vaccinated people still wear face masks whenever possible, citing the Delta variant’s increased transmissibility and risk of serious COVID-19 across the globe.
“People cannot feel safe just because they had the two doses. They still need to protect themselves… vaccines alone won’t stop community transmission,” Dr. Mariangela Simao, WHO assistant director-general for access to medicines and health products, said during a virtual press conference on June 25. “People need to continue to use masks consistently, be in ventilated spaces, hand hygiene, respiratory etiquette, the physical distance, avoid crowding.”
The advice arrived more than a month after the U.S. Centers for Disease Control and Prevention gave the green light for fully vaccinated Americans to ditch their masks in most scenarios — a time when little was known about the Delta variant or its whereabouts.
The CDC has yet to publicly respond to the WHO’s advice, but many health experts outside either agency seem to agree with erring on the side of caution.
“I personally think this is very wise advice. The #DeltaVariant is enormously contagious with even fleeting exposure of just seconds. This indicates clearly fast airborne transmission,” Dr. Eric Feigl-Ding, an epidemiologist, health economist and senior fellow at the Federation of American Scientists in Washington, D.C., wrote of the WHO’s advice on Twitter.
“You need to keep masking, especially premium masks if possible,” Feigl-Ding added.
Delta is growing around the world. Vaccinated are being infected. Protect yourself and fight to win.
Wear masks.
WHO urges fully vaccinated people to continue to wear masks as delta Covid variant spreads
1/https://t.co/Q5cbHBpNxn— Yaneer Bar-Yam (@yaneerbaryam) June 25, 2021
How do COVID-19 vaccines fare against the Delta variant?
A study from Public Health England found that three weeks after one dose, the Pfizer-BioNTech vaccine was 33% effective against symptomatic COVID-19 caused by the Delta variant. Two weeks following the second dose, which is recommended for full protection, it was 88% effective.
There isn’t any published data on how the Moderna or Johnson & Johnson COVID-19 vaccines fare against the Delta variant, but chief White House medical adviser Dr. Anthony Fauci told the Washington Post earlier this month that the Moderna shot, at least, should offer similar protection because its makeup is similar to that of Pfizer’s.
Despite the adequate protection the vaccines offer, some experts say masks add an extra layer of defense against the Delta variant, which is about 60% more contagious than the Alpha variant — one of the first variants of concern in the U.S. that initially emerged from the U.K.
Dr. Yasmeen Beg, an assistant professor of anesthesiology at Northwestern Medicine in Chicago, also agrees with the WHO’s advice on masks, at least while indoors.
“As the scientific community sorts out the significance of the #delta variant & new #DeltaPlus variant, the community should continue indoor masking especially in crowds/schools,” Beg wrote Sunday on Twitter. (The Delta plus variant is a slightly modified version of the Delta variant spreading in several countries, including the U.K., U.S. and India, CNN reports. Researchers are still trying to learn if it’s more dangerous than other variants.)
The CDC had advised that people who are fully immunised could meet with each other in an indoor setting without masks.This advise needs to be revised as the Delta/Delta plus variants are showing immune escape.
We need to continue to wear masks even if fully immunised.— Joey (@DrJoyeeta) June 24, 2021
As of Saturday, the Delta variant makes up more than 30% of the coronavirus cases in the U.S., according to Dr. Eric Topol, director and founder of the Scripps Research Translational Institute in California. Its presence doubles roughly every 11 days.
Nevada and Missouri are the variant’s current “epicenters” in the U.S., Topol wrote on Twitter, causing a rise in cases and hospitalizations there.
“It’s still early to assess the Delta hit. ... the next few weeks will be telling. Our genomic surveillance is still weak,” Topol wrote. “If vaccinations could be substantially increased ... we’d be in great shape to reduce its impact.”
Whereas most of the US is doing well, Nevada has joined Missouri in becoming the epicenter of the Delta variant hit. Both states are now Delta dominant and have rising cases and hospitalizations (~50% and 20%, respectively, past 2 weeks) pic.twitter.com/QytkeOPjeV
— Eric Topol (@EricTopol) June 27, 2021
More than 153.7 million Americans are fully vaccinated in the U.S., about 46% of the total population as of June 28, according to a CDC tracker.
However, “we still live in a world that is only partially vaccinated that has a lot of susceptibility, a lot of vulnerability,” Dr. Bruce Aylward, senior advisor to the WHO director-general, said during the Friday press conference.
The variant has been identified in at least 85 countries so far.
“We are already starting to see some consequences of these events with increasing transmission again. The Delta variant will make that epidemic curve exponential,” Dr. Maria Van Kerkhove, an infectious disease epidemiologist and the WHO COVID-19 technical lead, said during the press conference. “So, please, do what you can to keep yourself safe and make decisions individually about what [you] need to do every day.”
