Why You Need a COVID-19 Booster Shot
Studies have shown that booster shots can help restore waning vaccine-induced immunity and provide protection against a range of COVID-19 variants.
Former variants have been shown to reduce the effectiveness of the COVID-19 vaccines that are currently available, and future variants might do so as well. While vaccine manufacturers are exploring the possibility of variant-specific vaccines, the most effective way to stay protected against all types of COVID-19 is to get a booster shot of the vaccines once you are eligible.
Why You Need a COVID-19 Booster Shot Eligibility for Booster Shots Special Considerations for Immunocompromised Individuals Dosage and Variant-Specific Vaccines How Important Are Variants? Waning Immunity and the Importance of Boosters Vaccines Alone Are Not Enough What This Means for You Conclusion
Pfizer-BioNTech vaccine
In September, the FDA granted emergency authorization for a booster dose of the Pfizer-BioNTech vaccine, but only for select groups. On October 20, the FDA expanded its emergency use authorization to include the Moderna and Johnson & Johnson COVID-19 booster vaccines.
Eligibility for Booster Shots
Individuals who ended the original Pfizer vaccination series at least five months prior became eligible for a booster dose. Shortly after, the FDA authorized a booster dose for all adults who completed their original COVID-19 vaccine series and a Pfizer booster dose for adolescents ages 12 to 17. Eligibility was also expanded to include children as young as five years old.
The CDC recommends a first COVID-19 booster for everyone aged five and older.
Those who completed the Moderna or Pfizer primary vaccine series at least five months prior, or received the Johnson & Johnson vaccine at least two months prior, are eligible for a booster. According to the CDC, eligible adults can choose any authorized COVID-19 booster. However, it is recommended that individuals get the Pfizer or Moderna mRNA COVID-19 vaccine over the Johnson & Johnson vaccine due to concerns about blood-clotting side effects. The Johnson & Johnson shot remains an option for those who are not suitable or willing to get a different vaccine.
Children aged 5 to 17 who completed Pfizer’s primary shot series are only eligible for the Pfizer booster.
Special Considerations for Immunocompromised Individuals
Persons aged 12 and older who are moderately or severely immunocompromised (having an impaired immune system) should receive an additional dose of the mRNA vaccine 28 days after completing the two-dose mRNA series or the single-dose Johnson & Johnson vaccine. A first booster shot is recommended three months after receiving a third (additional) dose of the Pfizer or Moderna COVID-19 vaccine, or two months after getting a second dose if the initial dose was the Johnson & Johnson vaccine.
The FDA has also authorized a second mRNA booster dose for specific individuals at increased risk of severe COVID-19 illness. Persons aged 12 and older who are immunocompromised, as well as all adults aged 50 and older, should receive a second mRNA booster dose four months after their first booster dose.
Dosage and Variant-Specific Vaccines
The Johnson & Johnson and Pfizer boosters will be administered with the same dosage as the original vaccine, whereas Moderna’s booster will be a half-dose (50 micrograms). According to Moderna’s principal executive officer, Stéphane Bancel, “Recent preclinical results have shown that our variant-specific booster candidates were effective against COVID-19 variants of concern, and we hope to continually see positive results from the clinical studies.”
Moderna’s variant-specific vaccine candidates include one targeted explicitly against the Beta variant and a multivalent booster (for any variant) that combines the company’s original shot offering protection against Beta in a single dose.
How Important Are Variants?
The CDC created four groups for SARS-CoV-2 variants:
Variants Being Monitored (VBM)
- Variants that have or may pose a threat to approved or authorized medical countermeasures or have been associated with more severe illness (e.g., increased hospitalizations or deaths) or increased virus transmission but no longer pose a substantial public threat.
Variant of Interest (VOI)
A variant with specific genetic markers associated with changes to receptor binding, increased resistance to antibodies created by prior infection or vaccination, or reduced efficacy of treatments. A VOI may also increase transmissibility or disease severity and potential diagnostic failures.
Variant of Concern (VOC)
A variant causing increased transmissibility, more severe illness, or diagnostic detection failures. A VOC may also show evidence of a significant reduction in the effectiveness of treatments or a substantial decrease in neutralization by antibodies generated during prior infection or vaccination.
Variant of High Consequence (VOHC)
- A variant with clear evidence showing that prevention measures and medical treatments have substantially reduced effectiveness relative to previous variants.
In the United States, the only variant of concern is the Omicron variant. Currently, there is no variant of high consequence.
Waning Immunity and the Importance of Boosters
Because immunity created by most vaccines wanes with time, booster shots are necessary. It is not unusual for vaccines to require boosters to maintain high levels of immunity.
BioNTech’s co-founder and principal medical officer, Ozlem Tureci, MD, said she expects people to be vaccinated against SARS-CoV-2 annually because of the drop in immunity. During a Johns Hopkins press conference, Naor Bar-Zeev, PhD, MPH, associate professor and deputy director of the International Vaccine Access Center for the Department of Global Health at Bloomberg School of Public Health. emphasized that “we have to have a tetanus shot every 10 years.”
Bar-Zeev added that boosters become “all the more important in the current environment of variants. We’ll have the opportunity to reboot, revaccinate, broaden our protection, and make it more long-lasting.”
Vaccines Alone Are Not Enough
Bar-Zeev advised against viewing vaccines alone as sufficient to end the COVID-19 pandemic. “Vaccines are essential tools in general public health, but they’re not the only tool,” he said. As vaccination efforts continue, “we need to maximize every tool we have at our disposal. including masks, public restrictions where applicable, and distancing.”
What This Means for You
The variants of COVID-19 circulating worldwide and the waning of vaccine-induced immunity over time have motivated vaccine manufacturers to produce booster shots to help prevent severe illness. It’s recommended that you receive boosters for uninterrupted protection.
Conclusion
The Food and Drug Administration has granted emergency use authorization (EUA) for a booster dose of the Pfizer-BioNTech, Moderna, and Johnson & Johnson COVID-19 vaccines. These vaccines provide significant protection against the virus strains circulating in the U.S. and are highly effective at reducing hospitalizations and deaths.
