Just weeks after the Centers for Disease Control and Prevention recommended a second Covid-19 booster dose for people ages 50 and above, independent advisers to the agency are seeking to clear up confusion over which people in that age group may truly need that shot now and who could possibly wait until the fall for another dose.
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In March, the Food and Drug Administration authorized a second booster for people ages 50 and up four months after their first one. Shortly after, the CDC signed off on the FDA’s action, saying these individuals “may” get a second booster if they want, but it added that people should consult with their doctors to see if the second booster is necessary.
But the agency made the recommendation without consulting with its outside advisers, called the Advisory Committee on Immunization Practices, who typically hold a public meeting to review the evidence.
The seemingly sudden change in guidance left many doctors on the front lines confused.
“The doctors can’t keep up,” said Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center in Nashville, Tennessee, and medical director of the National Foundation for Infectious Diseases. “Nobody can keep up.”
During Wednesday's ACIP meeting, Elisha Hall, the clinical guidelines lead for the Covid-19 emergency response at the CDC, told the committee that people ages 50 and up should consider getting a second booster sooner rather than later if they have underlying health problems; live with others at high risk for severe Covid; or have jobs that put them at risk for Covid exposure, including those who travel or must gather in large groups.
People recently infected with the omicron variant could also wait until the fall, Hall said.
But the group also suggested that it's reasonable for doctors to ease up on people hesitant to get the second booster if they’re at low risk of disease — and wait until this fall to make the case for an extra shot if cases surge once more.
Even though Covid cases in the U.S. are rising slightly, they are nowhere near the height of the winter omicron surge. And, it seems, a different vaccine may be needed this fall — one that will target the highly contagious omicron variant.
"My sense is that omicron [and its subvariants] BA.2, 3 and 4 will be major players this fall," Moderna's chief medical officer, Paul Burton, said Tuesday during a meeting of the World Vaccine Congress in Washington, D.C. The company is working on a redesign of its vaccine to specifically target the omicron family of variants.
While there's no way of knowing what the coronavirus will do in the fall, many infectious disease experts worry that there will be another surge. That's because contagious subvariants are continuing to spread, and viruses generally spread more easily when the weather cools.
But there is also emerging evidence that additional boosters may result in diminishing returns.
"A few of my well-informed immunology, virology colleagues say that with each dose, you get less benefits," Schaffner said. That is, it's possible that the immune system sort of numbs with each additional dose of stimulant.
The number of new Covid cases has been ticking upward in recent weeks, as highly contagious omicron subvariants BA.2 and BA.2.12.1 continue to circulate. According to an NBC News tally, cases rose by more than 22 percent over the past two weeks, with a seven-day average of 41,670 new infections reported per day.
Covid-related hospitalizations and deaths, too, are increasing slightly.
In general, the illnesses tend to be mild enough to be managed at home, usually marked by extreme fatigue, body aches and upper respiratory symptoms.
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