Should You Get a Booster Shot?
Yes, you should get a COVID-19 booster shot if you are aged 5 years or older and it has been at least 2 months since your last COVID-19 vaccine dose, regardless of which vaccine you previously received. 1, 2
Current Universal Recommendation
The CDC recommends that all persons aged ≥5 years receive a bivalent mRNA COVID-19 vaccine booster dose at least 2 months after completing their primary series or after receiving a previous booster dose. 2 This recommendation applies universally to improve protection against COVID-19, particularly against Omicron variants that have shown increased immune evasion compared to earlier strains. 3
Age-Specific Booster Guidance
The specific booster recommendations vary by age group:
- Children aged 5 years: Pfizer-BioNTech bivalent booster ≥2 months after primary series or monovalent booster 1, 2
- Children aged 6-11 years: Either Moderna or Pfizer-BioNTech bivalent booster ≥2 months after primary series or monovalent booster 1, 2
- Adolescents aged 12-17 years: Either Moderna or Pfizer-BioNTech bivalent booster ≥2 months after primary series or monovalent booster 1, 2
- Adults aged ≥18 years: Either Moderna or Pfizer-BioNTech bivalent booster ≥2 months after primary series or monovalent booster 1, 2
Why Boosters Are Necessary
Vaccine effectiveness against COVID-19 has declined substantially during the Omicron-predominant period. 3 Monovalent COVID-19 vaccines demonstrated decreased effectiveness due to both waning immunity over time and the emergence of variants with increased immune evasion. 3 During the Omicron BA.4/BA.5 period, vaccine effectiveness against hospitalization among immunocompetent adults was only 49% at 14-149 days after the third dose and declined further to 34% at ≥150 days. 3
Bivalent boosters contain equal amounts of spike mRNA from both the ancestral strain and Omicron BA.4/BA.5 strains, which improves protection against currently circulating variants. 2 Real-world data demonstrates that booster shots provide consistently high protection against Omicron-related severe disease and death, with protection maintained for at least 3 months. 4
Special Populations Requiring Prioritization
High-risk groups derive the greatest benefit from booster vaccination and should be prioritized:
Older adults (≥75 years): Annual boosters reduce absolute annual risk of severe COVID-19 by 199 cases per 100,000 persons compared to a one-time booster. 5 The time for neutralizing antibody titers to decline to protective levels is shorter in older adults, necessitating more frequent boosting. 6
Immunocompromised individuals: These patients may benefit from additional protection and require special vaccination considerations, including additional primary doses and more frequent boosters. 1, 5 They may also benefit from supplemental protection with Evusheld (tixagevimab and cilgavimab) administered every 6 months. 1, 2
Adults aged 18-49 years: While boosters still provide benefit, the absolute risk reduction is more modest (14 cases per 100,000 persons with annual boosters versus one-time booster). 5
Timing Considerations
If you recently had COVID-19, you may consider delaying your booster dose by 3 months from symptom onset or positive test result. 1, 2, 7 This allows your natural immune response to mature before additional vaccination. 7 However, this is optional, and you can proceed with vaccination at the standard 2-month interval if preferred. 2
The minimum interval between your last COVID-19 vaccine dose and the booster is 8 weeks. 7 Delaying vaccination beyond recommended timeframes may prolong the period of suboptimal protection. 1
Alternative Options for mRNA-Intolerant Individuals
For adults who cannot or will not receive mRNA vaccines, the Novavax monovalent booster may be used if they completed any FDA-approved or FDA-authorized primary series, have not received any booster doses, and are unable or unwilling to receive an mRNA vaccine. 1, 2 The Novavax booster is authorized ≥6 months after the last primary series dose. 2
Common Pitfalls to Avoid
Do not use the Janssen (Johnson & Johnson) vaccine except in very limited situations due to the risk for thrombosis with thrombocytopenia syndrome. 1, 7
Do not assume you need to match vaccine manufacturers from your previous doses—you can choose from available vaccine options for your booster. 7
Do not delay boosters indefinitely based on prior infection alone—while a 3-month delay is reasonable, protection from infection alone wanes over time. 5
Do not assume younger, healthy individuals don't need boosters—while the absolute benefit is smaller, boosters still reduce risk of severe disease and help prevent transmission. 5
Evidence Quality and Strength
The recommendation for bivalent boosters is based on high-quality guideline evidence from the CDC/ACIP, published in the Morbidity and Mortality Weekly Report in 2022. 3 The ACIP voted 13 to 1 in favor of these recommendations after reviewing extensive data on vaccine effectiveness, safety, and implementation considerations using their Evidence to Recommendations Framework. 3 Real-world effectiveness data from multiple countries confirms that booster doses provide consistently high protection against severe disease and death during the Omicron-predominant period. 4