Why Do Seniors Need a Special Flu Shot?
As the human body ages, the immune system's effectiveness naturally declines in a process called immunosenescence. For older adults, this means their immune system may not respond as strongly to a standard-dose flu vaccine, leaving them more vulnerable to the flu virus. Consequently, people 65 years and older account for a disproportionately high number of flu-related hospitalizations and deaths every year. To counter this diminished immune response, special higher-potency vaccines are designed to give the body a stronger boost of immunity.
The Three Preferred Flu Vaccines for Older Adults
The Centers for Disease Control and Prevention (CDC) and its Advisory Committee on Immunization Practices (ACIP) preferentially recommend three types of quadrivalent flu shots for the 65+ age group, based on evidence suggesting they offer better protection than standard options. These vaccines are updated annually to match the circulating flu strains expected for the upcoming season.
1. High-Dose Flu Vaccine (Fluzone High-Dose Quadrivalent)
This vaccine contains four times the amount of antigen—the component that causes your immune system to produce protective antibodies—compared to a standard flu shot. By delivering a higher dose of antigen, it prompts a more robust immune response in older adults. It is an inactivated vaccine, meaning it contains killed flu virus strains and cannot cause the flu. Studies have shown it provides superior protection against influenza and its complications in this age group.
2. Adjuvanted Flu Vaccine (Fluad Quadrivalent)
This vaccine contains the same amount of antigen as a standard flu shot but includes an adjuvant, an ingredient that helps create a stronger, longer-lasting immune response. The adjuvant used in Fluad Quadrivalent, MF59®, is made from a naturally occurring oil (squalene) and has been used for many years. It is also an inactivated vaccine and is licensed for adults 65 and older. Research suggests it may help lower the risk of flu-related hospitalizations and pneumonia compared to standard-dose shots.
3. Recombinant Flu Vaccine (Flublok Quadrivalent)
Unlike the other two, this vaccine is not produced using the standard egg-based method. Instead, it is made using recombinant technology, which involves creating lab-made versions of the flu virus's key antigens. Flublok is egg-free, making it a suitable option for individuals with severe egg allergies. Studies have demonstrated that older adults show a better immune response to this vaccine than to standard-dose versions. It is approved for use in individuals aged 18 and older, including seniors.
Comparison of Preferred Flu Vaccines for Seniors
| Feature | Fluzone High-Dose Quadrivalent | Fluad Quadrivalent | Flublok Quadrivalent |
|---|---|---|---|
| Mechanism | Contains four times the antigen to boost immune response. | Contains an adjuvant (MF59®) to enhance immune response. | Created using recombinant technology (egg-free). |
| Recommended For | Adults 65+. | Adults 65+. | Adults 18+, including seniors with egg allergies. |
| Egg-Free? | No, it is egg-based. | No, it is egg-based. | Yes, it is egg-free. |
| Common Side Effects | Similar to standard shots, but may be more frequent. | Similar to standard shots, but may be more frequent. | Similar to standard shots, potentially milder reactions. |
Potential Side Effects and What to Expect
While the higher-potency vaccines are more effective, they can also cause more noticeable, though typically mild, side effects compared to standard-dose vaccines. This is a sign that your immune system is responding actively to the vaccine and building protection. Common side effects include pain, redness, or swelling at the injection site, as well as headache, muscle aches, and fatigue. These symptoms usually resolve within a few days. Serious side effects are very rare, and the benefits of vaccination far outweigh the risks for most seniors.
How to Choose the Right Flu Shot This Season
Choosing the best vaccine for you involves a conversation with your healthcare provider. Consider factors such as your health status, any chronic conditions, and potential allergies, particularly to eggs. If one of the preferentially recommended vaccines is unavailable, the CDC advises that getting any age-appropriate flu shot is better than none. The CDC website provides comprehensive information and guidance for vaccine decisions, so be sure to consult official sources for the latest recommendations and updates. Visit the official CDC influenza page here.
Conclusion
Staying up-to-date with flu vaccinations is one of the most effective ways for older adults to protect themselves from serious illness, hospitalization, and death. The newest recommendations prioritize high-dose, adjuvanted, and recombinant vaccines specifically designed to provide enhanced protection for those with a weakened immune system due to age. By understanding what is the new flu shot for the elderly and discussing your options with your doctor or pharmacist, you can make an informed decision to stay healthy this flu season. Remember, regular annual vaccination is the best defense against the flu.
