Fauci Says CDC Changed Mask Guidelines Because Vaccinated People Can Spread Indian ‘Delta’ Variant Spread
The country’s top infectious disease expert says India’s ‘Delta’ Covid variant has the same viral levels in vaccinated people with breakthrough infections as in unvaccinated people.
dr. Anthony Fauci told MSNBC on Wednesday that vaccinated people can spread Delta and explains why the Centers for Disease Control and Prevention (CDC) went back on mask recommendations for those who received their injections.
Previous research has 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.
But the CDC has yet to publicly share new research on Delta transmission among the vaccinated that would support its new mask guidelines. External experts ask the agency to show them the data.
Vaccinated people can spread Delta just like unvaccinated people, says Dr Fauci
Dr. Fauci: “The Delta variant has changed everything” “When the LEVEL of the virus is detected in the nasopharynx of a vaccinated person who gets an infection with #Delta, is EXACTLY SAME as the virus level in an unvaccinated person who becomes infected.
That’s the problem”@MSNBC pic.twitter.com/vdvs4CvgzB
— ciclbh (@ciclbh) July 29, 2021
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 whole landscape,” Dr. Fauci said Wednesday evening on MSNBC.
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.
In announcing the change, CDC director Dr. Rochelle Walensky quoted “new scientific data” consistent with Dr. Fauci’s statement: Vaccinated people can spread Delta.
The statement also ties in with a recent study from China that suggests that people infected with Delta have a 1,000 times higher viral load than people infected with older strains of the coronavirus.
But the new data from the CDC is not yet public, raising concerns about the agency’s transparency.
People infected with the Delta strain had 1,000 times more copies of the virus in their respiratory tract than people infected with the original strain (above), a recent study found.
A quote in the updated masking guidelines simply reads: ‘CDC COVID-19 Response Team, Unpublished Data, 2021.’
This data comes from studies of recent Delta-induced outbreaks, where researchers compared infections between vaccinated and unvaccinated people, according to the Washington Post.
The findings will be “published soon” per reporting from The Post.
But that’s not enough for some scientists — not even those who have endorsed the CDC’s new guidelines.
“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, told The Post.
“It’s pointless unless we see the data.”
Other experts are not convinced that a higher viral load actually leads to Delta transmission among vaccinated people.
“I feel like the nasal viral load is part of a lot of other parts” that determine how contagious a person is, biostatistician Natalie Dean told The Post.
Dean added that she thinks other important factors could be how much virus is present in a patient’s throat or lungs.
Experts like Dean want to see more data comparing the number of cases between vaccinated and unvaccinated Americans.
In recent months, the vast majority of severe Covid cases – leading to hospitalization and death – have occurred among the unvaccinated.
But the CDC doesn’t track less severe breakthrough infections. In May, the agency changed its strategy to investigate and report only those infections that cause hospitalization or death
Scientists have criticized this move before leaving the US without crucial data to track the cases caused by Delta and other variants.
Yet all Covid experts agree on one thing: Delta is of great concern and additional precautions are needed to stop its spread.
“Delta is alpha on steroids,” James M. Musser, chair of the Department of Pathology and Genomic Medicine at the Houston Methodist Hospital and Research Institute, told WaPo.