CDC Recommendations for Older Adults
For adults 65 years and older, the Centers for Disease Control and Prevention (CDC) and its Advisory Committee on Immunization Practices (ACIP) preferentially recommend three enhanced influenza vaccines over standard-dose, unadjuvanted options. This preference is based on studies showing these vaccines provide superior protection in this age group, which is at higher risk for severe illness, hospitalization, and death from the flu.
The three preferentially recommended vaccines are:
- High-Dose Inactivated Influenza Vaccine (HD-IIV4): Marketed as Fluzone High-Dose Quadrivalent, this vaccine contains four times the amount of antigen as a standard-dose shot. The higher antigen content is designed to prompt a stronger immune response, offering better protection. Studies have shown it to be significantly more effective than standard-dose vaccines in preventing influenza in older adults.
- Adjuvanted Inactivated Influenza Vaccine (aIIV4): Marketed as Fluad Quadrivalent, this vaccine includes an adjuvant—an ingredient that helps create a stronger immune response. It provides enhanced protection for those 65 and older by amplifying the body's response to the vaccine antigens.
- Recombinant Influenza Vaccine (RIV4): Marketed as Flublok Quadrivalent, this vaccine is created using recombinant technology and does not use eggs in its manufacturing process. It contains three times the antigen of a standard-dose vaccine, triggering a more robust immune response. This is an egg-free option, making it suitable for those with severe egg allergies.
If one of these enhanced vaccines is not readily available, any other age-appropriate inactivated influenza vaccine should be administered. The nasal spray vaccine (Live Attenuated Influenza Vaccine or LAIV) is not approved for adults over 49 and should not be used in older adults.
Why Older Adults Need Enhanced Flu Protection
As people age, their immune systems naturally weaken, a process known as immunosenescence. This makes older adults less able to mount a robust immune response to vaccination and more susceptible to severe flu complications. In fact, people aged 65 and older with chronic conditions like heart or lung disease are at the highest risk for life-threatening complications. Enhanced flu vaccines are designed to specifically address this weakened immune response. By providing a higher dose of antigen or incorporating an adjuvant to amplify the immune system's reaction, these vaccines are more effective at protecting a vulnerable population.
Comparing High-Dose, Adjuvanted, and Recombinant Vaccines
Choosing the right enhanced vaccine can depend on a person's specific health profile and preferences. The table below outlines the key features and differences between the three options preferentially recommended by the CDC for adults 65 and older.
| Feature | Fluzone High-Dose (HD-IIV4) | Fluad (aIIV4) | Flublok (RIV4) |
|---|---|---|---|
| Mechanism | Contains four times the antigen of a standard flu shot. | Includes an adjuvant (MF59) to boost immune response. | Made with recombinant technology and contains three times the antigen. |
| Egg-Free? | No, egg-based. | No, egg-based. | Yes, egg-free. |
| Immune Response | Creates a stronger antibody response due to higher antigen quantity. | Boosts the immune system's response to the vaccine. | Triggers a more potent immune reaction using laboratory-produced proteins. |
| Primary Benefit | Better prevention of flu and flu-related hospitalizations versus standard dose. | May lower the risk of flu-related hospitalizations and pneumonia. | Offers a non-egg option with enhanced protection for those with egg allergies. |
| Licensing | Approved for people aged 65 and older. | Approved for people aged 65 and older. | Approved for people aged 9 and older. |
Timing and Vaccination for Older Adults
The timing of vaccination is especially important for older adults. The CDC recommends getting the flu shot ideally by the end of October. Older adults should avoid getting vaccinated too early (e.g., in July or August), as their immunity may wane more quickly than in younger people. However, vaccination should continue as long as flu viruses are circulating.
It is also safe to get a flu vaccine and a COVID-19 vaccine or booster at the same time. The CDC also recommends that adults 50 years and older get pneumococcal vaccines to protect against pneumonia, a common and serious flu-related complication. You can often receive the pneumococcal and flu vaccines during the same visit.
Conclusion
In conclusion, for adults aged 65 and older, the CDC recommends prioritizing an enhanced flu vaccine—either high-dose, adjuvanted, or recombinant—to ensure the best possible protection against the severe outcomes of influenza. These vaccines are specifically formulated to stimulate a more robust immune response in a population with a weaker one. While an enhanced vaccine is the preferred choice, a standard-dose vaccine is a valid alternative if a preferred option is unavailable. An annual flu shot is an essential part of preventive care for older adults, and consulting with a healthcare provider can help determine the best timing and vaccine option for individual health needs.
Disclaimer: This information is for educational purposes only and is not medical advice. Consult a healthcare provider for personalized recommendations based on your health status and circumstances.
Flu Vaccine for Seniors: Understanding Your Options
What are the main types of flu vaccines recommended for older adults?
The CDC preferentially recommends three enhanced vaccines for people aged 65 and older: Fluzone High-Dose Quadrivalent, Fluad Quadrivalent (adjuvanted), and Flublok Quadrivalent (recombinant). These are designed to provide a stronger immune response than standard-dose vaccines.
Why are enhanced vaccines recommended for older adults?
As people age, their immune systems weaken, making standard vaccines less effective. Enhanced vaccines use a higher dose of antigen or an adjuvant to boost the immune response, offering better protection against severe flu illness, hospitalization, and death.
What is the difference between high-dose and adjuvanted flu vaccines?
The high-dose vaccine (Fluzone High-Dose) contains four times the amount of antigen to provoke a stronger immune reaction. The adjuvanted vaccine (Fluad) uses a standard dose of antigen but adds an adjuvant to amplify the immune response. Both are designed to enhance protection for older adults.
Is Flublok a good option for older adults with egg allergies?
Yes. Flublok is a recombinant, egg-free vaccine that is one of the three preferentially recommended options for adults 65 and older. This makes it a suitable and highly effective choice for those with a severe egg allergy.
What if an enhanced flu vaccine is not available?
If none of the preferentially recommended vaccines (high-dose, adjuvanted, or recombinant) are available, older adults should receive any other age-appropriate inactivated influenza vaccine instead. Getting any flu shot is better than none.
When is the best time for an older adult to get a flu shot?
The CDC recommends that older adults get their annual flu vaccine during September or October. Getting vaccinated too early (in July or August) may cause immunity to wane before the end of the flu season.
Can older adults get the flu shot and COVID vaccine at the same time?
Yes, it is considered safe and effective to receive the flu and COVID-19 vaccines or boosters during the same visit. This is often recommended to maximize protection against both respiratory illnesses.
