America prepares for a potential 4th COVID shot
Even as the Omicron wave winds down, federal health officials, experts and the vaccine makers are already preparing for a potential fourth COVID shot to protect against whatever may come next.
The catch: It's not yet clear whether another booster shot will be needed. And if it is, there are even more questions around who should receive one and what kind of shot would be most effective.
What they're saying: "The potential future requirement for an additional boost or a fourth shot for mRNA or a third shot for J&J is being very carefully monitored in real time. And recommendations, if needed, will be updated according to the data as it evolves," NIAID director Anthony Fauci told reporters last week.
- The federal government plans to test new vaccines that combine multiple strains of the virus to find what offers the broadest coverage, a senior Biden administration official told Axios. The goal is to increase the odds of having a shot ready that works against whatever strain comes next.
State of play: Fourth doses are already authorized for immunocompromised people. However, for most people, data suggests that a single booster shot offers strong protection against severe disease, including from Omicron.
- But the big question is how long that protection against hospitalization and death will last.
- The U.K. recently decided that it will soon offer fourth shots to the elderly and some people with health conditions, per The Sunday Times.
Between the lines: If protection does wane, officials will have to consider who would need another shot, and what that shot should be.
- Vulnerable people, for example, would most likely see much more benefit from another booster shot than young, healthy people — a distinction particularly important in light of global vaccination inequities.
- And while Pfizer and Moderna are both testing Omicron-specific vaccines, preliminary results from animal studies suggest that an Omicron shot doesn't offer much, if any, benefit compared to vaccines that target the original COVID strain. It also may not offer as much protection against other variants.
- "If by some amazing rarity there are people in the states who have neither been infected nor vaccinated and decide they want an Omicron vaccine ... the antibody response they generate would be quite narrow," said Cornell virologist John Moore.
Zoom in: Israel has already offered fourth shots and has begun to release preliminary data on their effect.
- One preprint released earlier this month found that a fourth shot offered only marginal improvement against infection over the third shot. However, a separate Israeli preprint found that a fourth shot led to lower rates of infection and severe disease.
The bottom line: The need for another booster shot will also depend on how much the virus keeps circulating.
- "It may not be as big an issue in the U.S. if we're really at a contained state," said Scripps Research Executive Vice President Eric Topol. But, he cautioned, we got lucky that a third shot of the original vaccine works so well against Omicron — and there's no guarantee that luck will hold against another variant.
- "We have to run not just on luck. This is not a casino here," Topol said. "We have to do better."