The new coronavirus booster that targets the omicron subvariants has been available for everyone 12 and older for nearly two months. (Federal health officials recently expanded eligibility to children 5 and older.) Yet as of last week, only 4 percent of eligible Americans have received it.
The data are clear on who is at highest risk for severe outcomes from covid-19. The Centers for Disease Control and Prevention reports that most people being hospitalized with the virus are 65 and older. The same is true for nearly 80 percent of deaths associated with the disease in 2022. People with underlying medical conditions who are more likely to end up seriously ill with any respiratory infection are also more susceptible.
The data are also clear that there is waning immunity against severe disease over time and that the immunity is restored with additional booster doses. Immunity wanes faster in older individuals and in people with chronic medical conditions. The new bivalent vaccine elicits a stronger antibody response against the dominant BA.5 omicron subvariant compared with the previous booster. All of these findings together make a compelling case for older adults and people with chronic medical conditions to receive the updated booster.
A recent Kaiser Family Foundation survey found that only 1 in 3 adults said that they have either received the updated booster or plan to do so. The rate is higher among those 65 and older, though even in this group, less than half said that they have received it or intend to do it soon. Awareness is also low, with only about half of adults reporting that they have heard of the new booster.
Clearly, there must be a coordinated booster campaign ahead of a likely winter surge. Now is the time for nursing homes to organize vaccine clinics where residents can receive both the covid and flu vaccines. Hospitals and insurers should identify their elderly patients and others with underlying conditions and call them to coordinate their boosters. Meanwhile, public health departments should resurrect mobile vaccine clinics and send them to senior centers and homeless shelters. And physicians should urge their vulnerable patients to receive the booster and be ready to prescribe Paxlovid or monoclonal antibodies if these patients contract covid.
This level of urgency should not be applied to the majority of Americans who do not fall into the high-risk category. For them, the benefit of the booster is to reduce an already-low likelihood of hospitalization even lower and to gain some additional — though likely short-term — protection against infection.
Some lower-risk people would happily get the booster and enjoy these benefits. Others might decide to time their inoculation ahead of, say, a big trip or a large family get-together. I think it’s reasonable for a generally healthy 40-year-old to wait until two weeks before high-exposure events to get their booster. I also think it’s reasonable for parents whose young kids completed their primary vaccination to hold off on additional shots for now. On the other hand, I’d strongly urge my patients 65 and older and adults with obesity, diabetes, lung disease and other serious underlying conditions not to delay their boosters.
Recent infection should also be taken into consideration. There is growing evidence that hybrid immunity — the combination of recovery from infection combined with vaccination — provides the strongest and most durable protection. It’s also becoming clear that prior infection with omicron subvariants conveys some protection against BA.5. People who recently contracted the coronavirus don’t need to rush to get boosted; they are unlikely to become reinfected soon after recovery, and there might be benefit to waiting at least three months.
I understand the rationale for the CDC’s blanket booster guidance, because overly complicated rules can also hinder uptake. But given the dismal booster numbers to date, federal health officials need to change course and focus their efforts to achieve the optimal public health outcome.
Health-care practitioners must also be mindful of preserving trust in their recommendations, which requires acknowledging that the evidence in favor of additional boosters is much stronger in some groups than in others. Targeting boosters to those most at risk, while giving options to everyone else, is our best hope against a likely next surge — and future public health emergencies.