COVID Delta variant: with vaccines, how to stay safe

The Delta variant of the coronavirus is proving to be a more formidable foe than previously believed, in large part due to its ability to infect – and spread by – fully vaccinated people.

A confidential document prepared by people within the Centers for Disease Control and Prevention offered a dire view of the threat posed by the Delta variant and suggested that more aggressive action would be needed to counter it.

“The war has changed,” the document warns.

We spoke with experts on how to stay safe in light of new developments. Here’s what they told us:

So what should we do?

Vaccination

Experts still agree that COVID-19 vaccines offer the safest route out of the pandemic. Indeed, the CDC document notes that as of Saturday, the rate of new infections was eight times lower among those who were vaccinated than among those who were not. Better yet, the incidence of hospitalizations and deaths from COVID-19 was 25 times lower for those vaccinated.

That said, many experts fear that if the vaccination no longer comes with the privilege of being able to get rid of face masks and social distancing, the shots will be harder to sell for health officials to those who are. still on the fence.

Wear masks indoors

The researchers found that when infected with the Delta variant, vaccinated and unvaccinated people had similar viral loads in their upper respiratory systems. This suggests that they are about equally likely to spread the virus to others – and a good reason to have recommendations or mandates for the use of indoor masks apply to everyone, which whatever the vaccination status.

The CDC this week announced new guidelines regarding the use of face masks. In parts of the country where coronavirus transmission rates are “significant” or “high,” everyone should wear face coverings when in indoor public spaces, the agency now advises.

Los Angeles County began requiring masks or other face coverings in indoor public places two weeks ago. And California strongly recommended the same this week.

Back to school

Many health experts have said moving forward with plans to reopen schools still made sense, even though children under 12 are not yet eligible to be vaccinated.

“Children need to be in school,” said Julie Swann, health systems engineer at North Carolina State University. “Those of us who lived last year, we know that.”

Swann recently released a report which found that without a mask in schools, 70% more children could be infected with the coronavirus within three months. Her research also shows that while the mask is required in all schools, she still expects 40% of elementary students to be infected within three months.

Despite those odds, she said, schools are expected to reopen for the 2021-22 school year, with additional mitigation strategies in place.

“Schools, counties and states can also increase testing of their population and community, which will also help slow the spread of the disease,” she said.

“If you weigh the risks against the benefits… I think it’s worth sending kids to school as long as there are mitigation measures in place,” added Dr Eric Ball, pediatrician at the Children’s Hospital of Orange County Primary Care Network.

What does the new data show?

The CDC cited new data from an outbreak this month in Barnstable County, Massachusetts, where 69% of eligible residents are vaccinated. Of 469 cases linked to gatherings at restaurants, bars and vacation homes, 74% were breakthrough infections in people who had been fully vaccinated. Of the 133 viral samples that were genetically sequenced, 90% were caused by the Delta variant or an offshoot of the strain.

The confidential CDC document also cites disheartening reports of groundbreaking cases in India, where the Delta variant was first detected. The viral loads of vaccinated people who were infected with Delta were higher than the viral loads of vaccinated people who were infected with other strains of coronavirus, according to these reports.

Growing evidence of Delta’s propensity to cause breakthrough infections is sure to complicate efforts to persuade immunization advocates to roll up their sleeves for COVID-19 injections – a challenge anticipated by the authors of the CDC document.

In the future, health officials will need to ‘improve [the] public understanding of breakthrough infections ”and stop“ describing breakthrough cases as ‘rare’ or as a ‘small percentage’ of cases, ”the document said.

How much is this new data making a difference?

Overall, it now appears that the Delta variant poses more risk than initially thought, but the vaccines available in the United States still offer strong protection.

“Delta is basically a coronavirus in gear,” said Dr. Gregory Poland, an immunologist at the Mayo Clinic in Rochester, Minn.

Scientists have established that people infected with Delta have about 1,000 times more virus particles in their upper respiratory systems than people infected with previous strains of coronavirus.

This difference allows Delta to pass from person to person just four days after an initial infection, said Chunhuei Chi, director of the Center for Global Health at Oregon State University. With the previous strains, it took about six days for this to happen, he said.

This rapid spread helps explain why the Delta variant, which reportedly arrived in the United States in March, now accounts for 82% of recent coronavirus infections in the United States, according to CDC estimates.

The evidence as to whether Delta causes more serious illness is less certain. The CDC document cited several studies, some preliminary, suggesting that Delta infections were more likely to lead to serious illnesses requiring hospital care.

Not everyone found this data convincing.

Neeraj Sood, a health policy expert at USC’s Sol Price School of Public Policy, said the CDC’s paper relies heavily on studies that have small samples and use viral load as a surrogate for severity. disease, which is not necessarily a precise substitution.

“I didn’t look and said, ‘There’s a pretty ironclad case that Delta is more virulent,’ he said.

Sood said the CDC also made the mistake of focusing too much on the growing number of breakthrough infections, which is to be expected when a growing share of the population is vaccinated. Instead, researchers should focus on the extent to which vaccines have lowered rates of severe illness and hospitalization in those infected, he said.

“If that won’t kill you, don’t put you in the hospital, I’m less worried,” he said.