From the Guidelines
I strongly recommend that most individuals, especially those who are 65 and older, immunocompromised, or have underlying health conditions, receive the latest COVID-19 booster shot, as outlined in the 2024 guidelines from the Advisory Committee on Immunization Practices 1. The current recommendation is to receive the updated formulation if you haven't had a COVID vaccine in the past 2 months. For most adults and children 5 years and older, a single dose is recommended, while children 6 months to 4 years may need multiple doses depending on their vaccination history, as detailed in the guidelines from the Advisory Committee on Immunization Practices 1. Key points to consider include:
- The booster can be obtained at pharmacies, healthcare providers, or community vaccination sites, and is typically free or covered by insurance.
- COVID boosters are important because immunity from previous vaccination or infection wanes over time, and the updated formulations target currently circulating variants.
- The vaccines continue to show strong effectiveness in preventing severe disease, hospitalization, and death, even as the virus evolves, as supported by the interim recommendations from the Advisory Committee on Immunization Practices 1.
- Side effects are generally mild and temporary, including soreness at the injection site, fatigue, headache, and muscle pain, typically resolving within 1-2 days. It's also important to note that persons who are moderately or severely immunocompromised may receive an additional age-appropriate dose of COVID-19 vaccine at least 2 months after the last recommended vaccine dose, as guided by the clinical judgment of a healthcare provider and personal preference and circumstances 1.
From the Research
Covid Booster Recommendations
- The CDC recommends that all persons aged ≥18 years receive a single COVID-19 vaccine booster dose ≥2 months after receipt of an Ad.26.COV2.S (Janssen [Johnson & Johnson]) adenovirus vector-based primary series vaccine 2.
- A heterologous COVID-19 mRNA vaccine is preferred over a homologous (matching) Janssen vaccine for booster vaccination due to the risks for rare but serious adverse events following receipt of a Janssen vaccine 2.
- Adults who received a primary Janssen vaccine dose should preferentially receive a heterologous mRNA vaccine booster dose ≥2 months later, or a homologous Janssen vaccine booster dose if mRNA vaccine is contraindicated or unavailable 2.
Vaccine Effectiveness
- The vaccine effectiveness (VE) against laboratory-confirmed COVID-19-associated ED/UC encounters was 24% after 1 Janssen dose, 54% after 2 Janssen doses, 79% after 1 Janssen/1 mRNA dose, and 83% after 3 mRNA doses 2.
- VE for the same vaccination strategies against laboratory-confirmed COVID-19-associated hospitalizations were 31%, 67%, 78%, and 90%, respectively 2.
- A study found that vaccine booster doses increased protection against COVID-19 hospitalization compared with a primary series, with relative VE against COVID-19 hospitalization in boosted mRNA vaccine recipients versus primary series only being 66% 3.
Booster Dose Strategies
- The Advisory Committee on Immunization Practices (ACIP) recommends an additional primary dose in certain immunocompromised recipients of an initial mRNA COVID-19 vaccination series, and a COVID-19 vaccine booster dose following a primary mRNA COVID-19 vaccination series in certain recipients aged ≥18 years 4.
- A study compared the clinical effectiveness of adenovirus vector-based Ad26.COV2.S (Janssen/Johnson & Johnson) to mRNA-based BNT162b2 (Pfizer/BioNTech) in a contemporary cohort of patients on dialysis, and found no difference in clinical effectiveness between the two vaccines 5.
- The benefits and risks of offering frequent boosters of mRNA vaccines for increasing population immunity against COVID-19 infection are still being studied, with some research suggesting that the optimal timing for offering booster doses and eligibility criteria are not yet well established 6.