July 29, 2021- 12:10 p.m.
The Centers for Disease Control and Prevention are coming under mounting pressure to release the data that led them to roll back mask guidelines on Tuesday as cities and states say they need to see the evidence before revising their own policies.
Federal officials say unpublished data showed that vaccinated people infected with COVID-19 could potentially transmit the virus, leading them to recommend that everyone should wear a mask indoors in high-transmission areas.
Republicans have questioned the new findings, and even Democrat-led cities say they won’t make changes without understanding the facts.
Iowa Governor Kim Reynolds said the change was confusing.
Scientists have also asked for the data to be released.
“They claim that people with delta who have been vaccinated and unvaccinated have a similar viral load, but nobody knows what that means,” Dr. Gregg Gonsalves, an associate professor at the Yale School of Public Health, to The Washington Post.
When CDC director Dr. Rochelle Walensky announced the reverse policy on Tuesday, she said “new scientific data” justified the move.
She said it came from research into “breakthrough” infections, comparing viral loads between vaccinated and unvaccinated people.But the CDC has yet to provide more specific information about the studies.
That information vacuum has been filled by, for example, House Minority Leader Kevin McCarthy, who claimed a doctor told him that the study was conducted in India with a vaccine that was not approved in the US.At the same time, democratically-run cities have said they cannot make changes without being fully aware of the facts.
At a news conference with Mayor Bill de Blasio, New York City Health and Hospitals president Mitchell Katz said, “Although the CDC issued their advisory at about 3 p.m. yesterday, they have not yet released their scientific reports on the data underlying to their recommendation.
‘He added that his focus remained on vaccinating people.“I think we owe it to the New Yorkers to, as you say, look at that information very carefully and understand its implications,” he said.
The day before, Anthony Fauci, the top infectious disease expert, told MSNBC that the latest information suggested that even vaccinated people can spread Delta and explains.
Previous research found that people infected with Delta have 1,000 times more copies of the coronavirus in their respiratory tract than people infected with older strains of the virus.
Since the start of the pandemic, a common measure used by scientists is ‘viral load’ – a measurement of how many copies of the coronavirus are in a patient’s body.When patients have a higher viral load – more copies of the virus – they are more likely to pass the virus on to someone else.
As the coronavirus has mutated into new variants, the viral load has increased. Delta is therefore now the most contagious variant.
In fact, according to Fauci, Delta is so contagious that even vaccinated people can spread it.‘We have a Delta variant that has changed the entire landscape,’ he says.
Nationally, the variant causes more than 80 percent of cases — and in some regions, it’s over 90 percent.
“If you look at the virus level in the nasopharynx of a vaccinated person who gets a breakthrough infection with Delta, it’s exactly the same as the virus level in an unvaccinated person who is infected,” Fauci said.
“That triggered the change in the CDC guideline,” referring to the agency’s recent backtrack on masking recommendations for vaccinated Americans.
In May, the CDC said anyone who completed a full vaccination regimen — two injections of Pfizer or Moderna, or one injection of Johnson & Johnson — could go anywhere without a mask.But this week, the agency said several groups of fully vaccinated Americans should go back to masking in public, indoor spaces.
This includes people living in areas with rapidly rising Covid cases, teachers in K-12 schools, and parents with children who are too young to be vaccinated.
