This post has been updated as of November 19, 2021.
After much debate, the Food and Drug Administration (FDA) has finally green lit the use of COVID-19 vaccine boosters in the US for all Americans above the age of 18
Given this decision, you may have some pressing questions about some important details. Below, we’ve explained everything you need to know about Covid-19 vaccine boosters – based on the latest guidance from public health experts.
Which booster shots have been approved? And how do they differ from the initial shots?
As of late October, the Food and Drug Administration (FDA) has approved booster shots for all three vaccines administered in the US (i.e. Moderna, Pfizer-BioNtech, and Johnson & Johnson.) Just this November, it approved the Moderna and Pfizer shots for emergency use in all adults.
Each of the boosters is a single shot, even if you initially received one of the two-dose mRNA vaccines. The boosters are each made from the same formulas as the original shots, except for the Moderna booster – which has been halved.
Wait, has the Johnson & Johnson vaccine booster been approved for all adults?
Yes! In fact, anyone 18 or older who received the one-dose Johnson & Johnson vaccine has been eligible for a booster shot for a few months. Why? Well, as Dr. Leslie Sude, a pediatrician at Yale Medicine, explained to Yale Medicine Magazine last week, “Some vaccine experts feel that the J&J vaccine should have always been a two-dose series.”
The J&J vaccine was already considered less effective than the Moderna and Pfizer shots. And new research shows that getting a booster shot two months after the primary dose can increase antibodies by four to six times the original response, bringing the vaccine’s efficacy much closer to the success rate of Moderna and Pfizer’s double-dose vaccines.
Should you mix and match vaccines, or stick with your original shot?
A flurry of studies across the globe have compared the antibody responses of mixing and matching vaccines. But most of the studies are still preliminary and there isn’t clear evidence yet to go one route or the other.
However, the FDA has authorized “heterologous (aka mix-and-match) boosters,” and the CDC encourages individuals to get any of the three boosters, regardless of their initial.
A highly-anticipated October study suggests the mRNA vaccine boosters – Pfizer and Moderna – produce more antibodies than the Johnson & Johnson booster, especially in individuals who originally received the Johnson & Johnson shot. Another recent NIH study released this week suggests Moderna boosters may better protect against new variants.
Based on this early data, some doctors are recommending individuals who initially received J&J get the Pfizer or Moderna booster. But not everyone agrees: Dr. Anthony Fauci recommends sticking with your original jab, since you already know what to expect. “If you’ve done well with one product, why not stay with the same product?” he mused to McClatchy last week.
What are the debates surrounding booster shots?
At this point, experts pretty much widely agree on the benefits of boosters for at-risk groups, like the elderly or those with underlying conditions. Israel has had an accelerated vaccine program, which gives us a hint at what the pandemic might look like in the US in the future. Data from its rollout suggests that boosters are very effective in reducing severity of COVID-19 in these types of vulnerable populations.
There’s still disagreement on whether everyone should eventually get a booster shot. Data shows that the original vaccines are performing very well in reducing hospitalization, death, and infectiousness – all key public health goals.
Plus, the greatest risk, by any measure, is not the waning effectiveness of the original vaccine, but not being vaccinated at all. Some public health experts believe precious vaccine stores should go to low-income countries struggling with mass-vaccination– in some countries, rates are as low as 1.8 percent – rather than into the arms of already vaccinated, healthy people.
But the Biden administration strongly supports expanding the use of boosters, and his top health officials have signed on, too.
Expert recommendations will continue to evolve. For now, they are recommending anyone who’s eligible for a booster shot get one. If you’re unsure, talk to your doctor. Stay tuned for updates!