“We cannot let (Delta’s spread) happen in the United States,” Dr. Anthony Fauci said Tuesday in a White House Covid-19 briefing, adding it’s “such a powerful argument” to get vaccinated.
The Delta variant is susceptible to available two-dose vaccines from Pfizer and AstraZeneca, he said, but protection from these vaccines requires following a two-dose schedule.
“There is reduced vaccine effectiveness in the one dose,” Fauci said. “Three weeks after one dose, both vaccines, the (AstraZeneca) and the Pfizer/BioNTech, were only 33% effective against symptomatic disease from Delta.”
He added that variant-specific boosters may be on the horizon.
Even those who’ve already had coronavirus should get vaccinated because research shows immunity achieved through vaccination is better than immunity through previous infection, Fauci said.
Meanwhile, the country has averaged almost 14,380 new Covid-19 cases a day across the past week — the second-lowest average since March 28, 2020, according to Johns Hopkins University data. Only Friday’s average — 14,328 per day — was lower.
But health experts are warning that a recent lag in vaccination rates leaves millions unprotected against Covid-19 variants that have made their way to the US from other parts of the world.
Over the last week, the US averaged more than 1.07 million Covid-19 vaccine shots administered per day — well below the peak seven-day average of 3.38 million shots per day reached on April 13, according to CDC data.
Vaccine hesitancy and accessibility issues
As the US enters what the former CDC director called the “slog-phase of the vaccination campaign,” health experts have been drawing attention to both vaccine hesitancy and accessibility issues.
Houston Methodist became the first major health care system in the US to mandate Covid-19 vaccinations on March 31, starting with managers, according to an initial announcement from Houston Methodist CEO Marc Boom.
Boom told CNN that those who did not comply with his vaccination hospital’s policy were suspended after violating the tenets of the medical profession.
“Every one of our professional tenets require us to put patients first, require us to keep our patients safe, by anything we can possibly do, so those individuals who are choosing not to get vaccinated are basically saying they are going against the tenets of our profession and they’re not putting patients first,” Boom said.
CDC issues new international travel guidance
The CDC uses levels 1 through 4 to determine a threat in a given country, 1 being the lowest risk and 4 being the highest, depending on the number of Covid-19 cases. At each level, the CDC advises getting vaccinated, but its guidance for unvaccinated people varies by how severe the pandemic is in each country.
Iceland, Israel and Singapore were added Monday to the lowest risk category. Brazil, India and Iraq are currently in level 4, which means they’ve had more than 500 cases per 100,000 residents in the last 28 days.
For countries at level 3, such as Mexico, Russia and Iran, the CDC recommends against nonessential travel for those who are unvaccinated. These countries are currently reporting 100 to 500 cases per 100,000 residents.
The agency also recommends that unvaccinated travelers who are at severe risk for severe illness from Covid-19 should not visit countries in level 2, which include Finland, Cambodia and Kenya.
Finally, countries at level 1, such as Australia and New Zealand, are considered the lowest risk destinations, reporting less than 50 Covid-19 cases in the last 28 days. The CDC still recommends getting vaccinated before traveling to a low-risk location.
Correction: An earlier headline and version of this story incorrectly characterized the latest seven-day average of new daily US coronavirus cases as the lowest since March 2020; it is the second lowest since March 28, 2020. An earlier version also incorrectly stated the latest seven-day average of vaccine shots administered per day.
CNN’s Hollie Silverman, Holly Yan, Amir Vera, Ryan Prior and Carma Hassan contributed to this report.