COVID-19 Vaccine Update for Fall 2024
No, the current COVID-19 vaccine is not the same as the one that will be available in fall 2024. The FDA has approved and authorized new Omicron JN.1 lineage (JN.1 and KP.2) vaccines for the 2024-2025 season, replacing the previous XBB.1.5 formulation used in 2023-2024. 1
Vaccine Strain Updates for 2024-2025
The 2024-2025 COVID-19 vaccines have been specifically updated to target currently circulating SARS-CoV-2 strains:
- Moderna and Pfizer-BioNTech: Updated to target the KP.2 strain (JN.1 lineage)
- Novavax: Updated to target the JN.1 strain 1
This update was necessary because the previous 2023-2024 COVID-19 vaccines were designed to protect against SARS-CoV-2 XBB-sublineage strains, which are no longer predominant in the United States. 1
Effectiveness of Updated Vaccines
Early data on the 2024-2025 COVID-19 vaccines shows promising effectiveness:
- Against COVID-19-associated emergency department/urgent care visits: 33% (95% CI = 28%-38%) during the first 7-119 days after vaccination 2
- Against COVID-19-associated hospitalization in immunocompetent adults aged ≥65 years: 45-46% during the first 7-119 days after vaccination 2
- Against COVID-19-associated hospitalization in adults aged ≥65 years with immunocompromising conditions: 40% (95% CI = 21%-54%) during the first 7-119 days after vaccination 2
Vaccination Recommendations
The Advisory Committee on Immunization Practices (ACIP) recommends 2024-2025 COVID-19 vaccination for all persons aged ≥6 months to provide protection against severe COVID-19-associated illness and death. 1
For persons without moderate or severe immunocompromise:
- Ages 5-11 years: 1 dose of 2024-2025 COVID-19 vaccine (Moderna or Pfizer-BioNTech)
- Ages ≥12 years: 1 dose of 2024-2025 COVID-19 vaccine (Moderna, Novavax, or Pfizer-BioNTech)
- Exception: Unvaccinated persons ≥12 years choosing Novavax should receive 2 doses 1
For persons with moderate or severe immunocompromise:
- Additional doses may be recommended based on vaccination history
- Unvaccinated persons aged 6 months-11 years: 3-dose series of 2024-2025 mRNA COVID-19 vaccine
- Unvaccinated persons aged ≥12 years: 3 doses of 2024-2025 mRNA vaccine or 2 doses of 2024-2025 Novavax 1
Clinical Implications
The regular updating of COVID-19 vaccines is critical for maintaining protection against evolving SARS-CoV-2 variants. The disease continues to cause significant morbidity and mortality:
- In 2023 alone, there were 44,059 COVID-19-associated deaths in persons aged ≥65 years, 5,634 among persons aged 20-64 years, 125 among persons aged 1-19 years, and 58 among infants aged <1 year 3
- COVID-19 continues to account for thousands of hospitalizations and hundreds of deaths in the United States each week 3
Common Pitfalls in COVID-19 Vaccination
Assuming previous vaccination is sufficient: The effectiveness of previous COVID-19 vaccines wanes over time and may not protect against current variants. For example, VE against COVID-19-associated hospitalization declined from 49% at 7-59 days to just 14% at 120-179 days after 2023-2024 vaccination. 1
Overlooking high-risk populations: Adults aged ≥65 years and those with immunocompromising conditions remain at highest risk for severe outcomes and may benefit most from updated vaccines. 1, 2
Delaying vaccination: Waiting for a "better" vaccine in the future may leave individuals vulnerable during periods of increased transmission.