August 16, 2022

The swift rise of omicron subvariant BA.5—with its increased immune-evading abilities and demonstrable growth advantage—has federal officials on edge. In a flurry of activity late Monday and early Tuesday, officials doubled down on pandemic measures, renewed calls for vigilance, and are considering expanding eligibility of second boosters to all adults.

In a press briefing Tuesday morning, White House COVID-19 Response Coordinator Ashish Jha outlined a battle plan against BA.5, which, as of today, is estimated to account for 65 percent of cases in the US. Jha highlighted efforts and tools to prevent another towering wave of infection as seen with the original omicron in January. The plan includes a stronger push to get Americans vaccinated and boosted, plus renewed encouragement to test, treat, mask, and improve indoor ventilation.

US COVID-19 cases are currently plateaued at a high level of around 117,000 new cases per day—but that’s likely a significant underestimate given that many Americans are testing at home and not reporting their cases. Hospitalizations and intensive care admissions, meanwhile, are rising, with 17 percent and 21 percent increases over the past two weeks, respectively, according to tracking by The New York Times. Generally, the daily average of hospitalizations has more than doubled since the end of May, with the current average nearing 38,000.

SARS-CoV-2 transmission levels are considered high in about 90 percent of US counties, according to a red-soaked map from the Centers for Disease Control and Prevention. The agency recommends that everyone wear masks in public indoor settings in around 21 percent of counties, based on the agency’s gentler COVID-19 community-levels metric.

The current vaccines have proven highly effective at preventing severe disease, hospitalizations, and death. But to date, only 67 percent of Americans are fully vaccinated against the pandemic virus. Of the fully vaccinated, only 48 percent have received a booster. That means that just around 32 percent of Americans have had one booster, which is available to everyone ages 5 years and up. Additionally, people ages 50 and up or at high risk (such as immunocompromised) are currently eligible for a second booster. But only 18.7 million people have gotten that second booster. That’s about 28 percent of the people over age 50 who are fully vaccinated and boosted.

On Monday evening, The Washington Post broke the news that the Biden administration is considering expanding eligibility of second boosters to include all adults. The report cited five unnamed officials with knowledge of the matter, who said that Jha and top infectious disease expert Anthony Fauci support the idea of expanding second boosters to all adults.

In the press briefing Tuesday morning, Fauci and Jha stressed that only the Food and Drug Administration and the CDC have the ability to ultimately expand booster eligibility. The Washington Post noted that administration officials hoped to have the regulatory sign-off on the expansion within the next two weeks. The quick timeframe could keep a summer booster expansion from complicating the rollout of next-generation boosters this fall.

Boost now and later

Currently, the administration and the FDA are anticipating the rollout of next-generation, bivalent boosters this fall that would target both the ancestral strain and the BA.4/5 omicron subvariants. That rollout is expected to begin around October or November, or roughly three to four months from now. In the past, booster intervals have been around four to six months, Jha noted.

Jha and CDC Director Rochelle Walensky said repeatedly Tuesday that getting a booster now—or in two weeks or so—would not preclude getting a bivalent booster this fall. Their thinking is simply based on the time frame and anticipated interval for boosters.

“As we’ve looked at the cadence of where we’ve needed to get boosts before, it’s been four, five months,” Walensky said. “We anticipate that that’s going to be a similar cadence. We also really want to emphasize that there are many people who are high risk right now, and waiting until October/November for their boost—when, in fact, their risk is in the moment—is not a good plan,” she added. “So, we really do want to say ‘Now get your boost. We have every anticipation that the data will suggest that you will be eligible for a [bivalent] boost in the fall. We will, of course, continue to evaluate those data.”

For now, there’s no clinical data on the efficacy of a second booster in healthy people younger than 50. It’s also unclear if a fourth dose with the current vaccines—which target the ancestral strain of SARS-CoV-2—could skew immune responses to future variant-targeting boosters back toward the ancestral strain. But this has not been a significant concern for people already eligible for second boosters. Additionally, a majority of Americans have already been exposed to variants.

As such, many experts have, like Jha and Fauci, embraced the idea of expanding second booster access amid the BA.5 spike. That includes virologist and vaccine expert Peter Hotez, who is dean of the National School of Tropical Medicine at Baylor College of Medicine.

“We have already seen the benefits in 50 and older,” he told the Post. “Eventually what’s true for older people turns out to be true for younger folks—it just takes longer to reveal itself.”

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