That’s why experts say the United States should also intensify its tests: not only to track infections and antibodies, but also variants.
“We are late in testing from day one,” said Kathleen Sebelius, former secretary of Health and Human Services, on Saturday. The United States now needs to “focus on the tests we need to identify who has the disease and then on the serology tests that will tell us more about antibodies and what type of variant is circulating.”
5.5% of the US fully vaccinated
Although vaccinations are in progress, they are unlikely to help the United States achieve herd immunity levels anytime soon.
More than 17.8 million people have been fully vaccinated. That is about 5.5% of the US population.
Herd immunity is achieved when the majority of the population becomes immune to an infectious disease – either through infection and recovery, or through vaccination. Dr. Anthony Fauci estimates that between 70 to 85% of the United States’ population needs to be immune for collective immunity to take effect against the virus.
The IHME team wrote that it does not expect the country to achieve herd immunity before next winter.
“The model suggests that we should have a peaceful summer,” IHME director Dr. Chris Murray told CNN on Friday. “But we know that Covid is really seasonal, so when the next winter comes, we will need to have a much higher level of protection to stop Covid in its path than we are likely to achieve.”
To speed up obtaining at least the first doses of weapons, the United States should consider postponing the second dose of vaccines, another expert said.
“Everyone needs a second dose, there is no doubt about it,” said Dr. Ashish Jha, dean of Brown University School of Public Health. “I think the point is, now we are going to wait four weeks between the first and the second dose. And if it were six weeks or eight weeks or 10 weeks – not much more than that.”
Their comments came the same day, two senior US officials – Andy Slavitt, senior adviser to the White House Covid-19 response team and Fauci – said they did not think the US should delay or skip the second dose of the vaccine. Jha says his suggestion is a compromise to get more high-risk people vaccinated quickly.
The teachers’ union calls the CDC guidelines a ‘safety guardrail’
In the midst of continuing vaccination challenges and concerns over the rise of another case, local leaders are also working to see what a safe return to school is like.
The vaccine and the tests are “additional layers” of protection, the agency said.
“There are opportunities for personal learning at all stages of … community outreach,” said Walensky. “I would really invite schools to lean over and see what is needed … to try to get more and more children back to school.”
Randi Weingarten, the president of the American Federation of Teachers, told CNN on Saturday that the agency’s guidelines are a “protective grid” for teachers – and in a recent survey, most educators said they would feel comfortable going back to school with the help of tests, vaccine prioritization and mitigation strategies in place.
And schools face another challenge when it comes to reopening for face-to-face classes, Weingarten added.
When schools implement some of these measures, including smaller classes and social distance, they need more space and more educators, Weingarten said.
“The reason you have so many places that are hybrid is because they have no space and no educators,” she said. “The real question now is how we can help transform places that are remote.”
CNN’s Maggie Fox and Lauren Mascarenhas contributed to this report.