The messaging on vaccine boosters is muddled and confusing, yet the science is pretty straightforward and reassuring. Your vaccine is still cutting your risk of getting a severe case or dying from Covid-19, even if it has been a number of months since you got it.
Whenever they received the first shots, an extra jab is recommended for people over 65 and those with any number of immunity-compromising health conditions, or conditions that vastly raise Covid-19 risk, which are listed by the Centers for Disease Control. But what about if you are young and healthy and vaccinated?
“All three vaccines currently used in the United States will continue to protect against severe illness at a high level, and there’s no evidence of erosion,” Paul Offit, a vaccine expert at the Children’s Hospital of Philadelphia, told me.
Eric Toner, a senior scholar at the Johns Hopkins School of Public Health, largely agrees. One reason there’s been debate, he said, is that the Pfizer and Moderna vaccines already offer pretty good protection, even after seven to nine months.
The biggest change is the recommendation from the CDC last week that everyone who had the single shot of the Johnson & Johnson vaccine get a second one — not because the single dose doesn’t work but because some measures suggest it isn’t as protective as the other vaccines available in the US. The J&J vaccine’s efficacy against severe disease has most recently been measured at 74%, which goes up to 94% with boosters, according to clinical trials. The second shot brings it in line with Pfizer’s and Moderna’s, which are still showing over 90% protection against severe disease even as protection against milder infections now looks lower than it did last spring.
The other big change, which should be reassuring, is that your second or third shot can be any of the three vaccines offered in this country. There doesn’t seem to be any risk to mixing and matching.
Toner emphasized that since there’s consensus now about who should get a booster shot, there’s little need for an antibody test to try to determine whether your protection is wearing off. For one thing, it’s not clear how well antibody tests correlate with an individual’s protection, he said. And immunity is complicated — you also get long-lasting virus-fighting cells, those B and T cells, which hide in your bone marrow and lymph nodes.
Risk is more important than antibody levels, and scientists have been consistent in recognizing that it is vastly higher for older people. And they’ve consistently said that breakthrough infections are usually mild, or at least not life threatening enough to require hospitalization, but can be deadly in those with certain conditions which damage the immune system — people such as Colin Powell, who died at 84 from Covid-19 after a long battle with cancer.
Scientists have also been consistent in the message that the risks posed by the vaccines and boosters are low. So for people facing higher odds of contracting the disease, the benefits of an extra shot clearly outweigh the risks.
Still, people are confused by the mixed messages they are getting about whether the vaccines are wearing off or don’t work as well as we were told. When I looked into this for a column last summer, Eric Topol of the Scripps Research Translational Institute in La Jolla, California, complained while the news was full of alarming reports of surging hospitalizations, nobody couldn’t find basic, crucial information about those hospitalized people — their ages, health status, whether they were vaccinated, which vaccines they got and when they were administered.
It was also a mistake for some doctors to try to push a message that vaccines didn’t prevent people from transmitting the virus, said Monica Gandhi, an infectious disease doctor at the University of California, San Francisco. That message comes across as baffling or disingenuous when people are then urged to get vaccinated to protect other people. The bottom line, she said, is that the shots do vastly reduce the odds you will infect other people.
The vaccines not only make it much less likely you’ll get a severe case. They also reduce the number of mild or asymptomatic cases, and vaccinated people clear the virus faster if they are infected, so the shots reduce the odds you’ll give anyone the disease.
They’re not perfect. That’s why the experts agreed that a booster is also a good idea for health-care and nursing-home workers or others whose job puts them at risk or in contact with vulnerable people.
Don’t blame the experts for the confusion. Many have gone far out of their way to help people understand what’s going on, including the three interviewed for this column. But they don’t always have access to the information they’d like.
A recent press release from Pfizer, for example, touted a study in which 10,000 people were followed after getting either two or three shots. The results sounded impressive: 109 became infected in the two-shot group and only 5 in the three-shot group. But the press release didn’t say what level of infection they tracked — was it severe or mild or just a positive test? Nor were the ages specified.
As I wrote last summer, part of the problem is numbers can be spun different ways, depending on whether the object is to persuade people to get the vaccine or to persuade the vaccinated to wear masks in public. The messages that have rung true and held up over time are those that aim not to scare people or change their behavior but to inform us how to understand and mitigate our own risks and recognize our responsibilities to others.
Bloomberg
