Biden administration hopes to roll out COVID-19 boosters on Sept. 20 after new data

The Biden administration plans to roll out a booster shot for COVID-19 vaccinations starting on Sept. 20, directing Americans to get an extra shot eight months after their second dose.

The announcement on Wednesday comes as new data shows waning effectiveness of the Pfizer and Moderna vaccines of preventing infections, even as prevention of severe disease and hospitalization remains strong. Another concern is the impact of the highly transmissible delta variant, which has led to a major surge of the virus across the U.S.

“While vaccines are working well, we are seeing concerning evidence of waning vaccine effectiveness over time against the delta variant,” said Centers for Disease Control and Prevention Director Rochelle Walensky during a briefing of the White House’s COVID-19 task force on Wednesday.

Walensky pointed to two vaccine effectiveness cohort studies that show waning effectiveness against symptomatic and asymptomatic infections.

One study from New York examined COVID-19 tests and vaccination status and found that effectiveness against infection declined from 76% to 42% for Pfizer’s mRNA vaccine and Moderna’s effectiveness reduced from 86 to 76%.

Another study to be published by CDC today examined the effectiveness of vaccines against infections in nursing homes. The study found that vaccine effectiveness declined from 75% in March to 53% as recently as Aug. 1, Walensky said.

“Taken together while the exact percentage of vaccine effectiveness over time differs, the data consistently demonstrates a reduction of vaccine effectiveness over infection over time,” Walensky said.

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But she added that the data still shows stable protection against severe disease and hospitalization.

“Effectiveness against hospitalization is relatively high,” she said.

However, officials were concerned that eventually, that protection will start to wane, hence the need to plan for a booster.

“Around the six-month mark in the data you start to see increases in mild to moderate infection, but we know the most important purpose of the vaccine is to keep us out of the hospital and save our life,” said Surgeon General Vivek Murthy during the briefing. “Fortunately we are seeing that holding.

But the trajectory is that such protection may start to lessen and there could be an increase in breakthrough hospitalizations and deaths, he said.

“There is nothing magical about this number,” he said of the eight-month timeframe. “This is where judgment comes in and why we put so much time into this decision.”

White House senior COVID-19 advisor Jeffrey Zients said that the administration is prepared for boosters and aims to “hit the ground running.”

However, several factors could delay the rollout, chief among them is whether the Food and Drug Administration will make an amendment to the emergency approval for the vaccines.

Zients said that the Sept. 20 date is what they are working towards but it is pending both the FDA’s approval and a recommendation from the CDC’s Advisory Committee on Immunization Practices, which drafts recommendations on administration of all types of vaccines.

Murthy said that the goal of announcing the booster plan now, before the FDA approves it, is to give states and stakeholders time to prepare for such boosters should they get approved.