The most critical lifesaving tool we have in this pandemic is vaccination against the virus that causes COVID-19. All of the vaccines that have been licensed in the United States have been proven to be extremely safe and reliable. And we've known from the start that the robust protection they provide would eventually wane.
However, has protection deteriorated sufficiently to warrant booster shots? Recent studies published by researchers in the United Kingdom, Israel, and the United States (reviewed here and here) raised this possibility, and Israel and the United Kingdom have already launched ambitious booster programs.
Vaccinate every single person.
You might be aware, that the CDC and FDA conducted a review of the need, safety, and effectiveness of boosters for the Pfizer/BioNTech vaccine. In the coming weeks and months, both agencies will conduct a review of data for Moderna and Johnson & Johnson. This is the only booster shot available right now.
But first and foremost, it's critical not to overlook this fact: vaccinating the unvaccinated should take priority over booster shots for those who have already received vaccines. This is true for individuals in the United States who have been unable or unwilling to obtain the vaccine, as well as individuals in other parts of the world with limited access to vaccines.
Not only would expanding the pool of people who have received their initial vaccinations save more lives than promoting boosters, but it would also help reduce COVID-related healthcare disparities between richer and poorer countries. That is why the World Health Organization (WHO) has called for a moratorium on booster doses. Biden administration officials announced that an additional 500 million vaccines would be donated to developing countries with low vaccination rates, bringing the US commitment to 1.1 billion doses. The administration emphasizes that establishing a booster program in the United States and assisting other countries in vaccinating their citizens are not mutually exclusive.
Is a booster dose different from a third shot?
Not all additional vaccine doses are boosters. FDA approved a third dose in August 2021, the Pfizer or Moderna vaccine for immunocompromised individuals. This includes individuals living with HIV and those undergoing cancer treatment that suppresses the immune system. The extra dose is not considered a booster for them; it is considered part of their initial immunization series.
Choosing the right time to receive vaccine boosters
Ideally, vaccines booster are administered no sooner than necessary, but well before widespread protective immunity begins to decline. The dangers of waiting too long are self-evident: as immunity declines, infection, serious illness, and death rates may begin to rise.
However, there are downsides to administering boosters prematurely:
Side effects may be more common. While published research indicates that boosters are safe, we don’t yet have long-term data.
The benefit may be small. It may be advisable to wait on booster vaccinations if the majority of people are still protected by their initial vaccinations.
It's possible that current boosters won't cover future variants. Boosters may be modified to include new variants of concern in the coming months.
Pfizer/BioNTech vaccine booster recommendations
The CDC and FDA have concluded that boosters are necessary for some recipients of the Pfizer/BioNTech vaccine. A booster dose is recommended at least six months after the second dose for those who are :
- 65 years of age or older.
- 18 to 64 years of age and at a high risk of developing severe illness from COVID, such as those who have chronic lung disease, cancer, or diabetes.
- Residents of long-term care facilities, healthcare workers, teachers and daycare staff, grocery workers, and prisoners all work in high-exposure environments.
There are currently no Pfizer/BioNTech boosters recommended for the general population. This is because the initial doses continue to provide adequate protection against serious illness and death.
Countless unknowns
The publication of these new recommendations for Pfizer vaccine boosters raises several concerns:
How credible is the safety data? To date, reports indicate that boosters are safe, but additional research and real-world data are needed.
Moderna and Johnson & Johnson boosters are still awaiting FDA approval. When can we expect that?
Should all boosters contain the same vaccine as the initial regimen, or does mixing vaccines provide additional protection?
The unfortunate thing is that some people are combining vaccines on their own, sometimes by falsely stating they didn't get the COVID shot before getting a different kind of shot altogether.
Will booster doses be identical to initial doses? So far, the answer for the Pfizer/BioNTech vaccine has been affirmative. If the Moderna booster is authorized, it will very certainly be for a half-dose.
Will boosters be altered to protect against new variants?
Will there be a future need for additional boosters? If so, how frequently?
In the coming weeks and months, look for answers to these questions.
What is next?
Based on ongoing review and analysis of available research, the FDA and CDC are expected to revise and expand booster recommendations. Meanwhile, we should intensify our efforts to vaccinate those who have not received vaccines. Individuals can benefit significantly from boosters. However, as Dr. Rochelle Wallensky, director of the CDC, notes, "we will not boost our way out of this pandemic."
