Why do we need a booster? A UW immunologist explains

The pandemic has taken a toll on all of us. And polarizing views and misinformation about vaccinations and safety precautions have produced a stunning amount of confusing information. Immunologist Dr. Marion Pepper wants to help break through the noise to find a better understanding of booster shots.

This September, Pepper became interim chair of the Department of Immunology. But she has long been a national news resource about vaccines, how they work and their effectiveness over time. In the “Pepper Lab” at the UW School of Medicine, the team studies ways to enhance immune memory—the immune system’s ability to react quickly to a virus—to design more effective vaccines.

But what exactly is a booster? According to Pepper, “booster is just a name that we give a shot, a vaccine that is an additional shot beyond the original vaccine regimen.” Now that boosters are available to all adults who received a COVID-19 vaccine at least six months ago, there is less confusion about who needs one. But it comes highly recommended to anyone who received the single Johnson & Johnson dose as well as those 65 and older and those who are immune compromised who received the Moderna or Pfizer vaccine. The booster shot helps “reinvigorate their immune memory cells and produce a layer of immune protection that had faded,” Pepper says.

According to the Centers for Disease Control, people with cancer, many chronic diseases and HIV should get a booster. So should people who work or live in high-risk settings like schools, health care facilities and prisons, or who live in long-term care facilities. “This is to create an extra layer of antibodies to protect against infection until we get through Delta variant surge that we’ve all been hearing a lot about,” Pepper says.

News of boosters has stirred concerns about vaccine effectiveness. But “the vaccines are working really well,” Pepper says. “They are doing what they set out to do, which is to protect against disease and hospitalization. The booster shot can make you more protected against infection, but it doesn’t mean that the original vaccines aren’t working.”

Since boosters are available, people may wonder about the meaning of being fully vaccinated. “Fully vaccinated just means that you underwent the series of shots that were associated with the original vaccine regimen,” Pepper says.

Beyond boosters, those who haven’t yet been vaccinated should do so as soon as possible, Pepper says. “It’s not only to protect themselves, but also the community around them.”