Influenza continues to pose a significant health threat, particularly for older adults. This vulnerable population faces a disproportionately higher risk of severe illness, hospitalization, and mortality from influenza infection. Understanding the unique challenges and the most effective strategies for prevention and control is crucial for pharmacists, who are at the forefront of patient care during flu season. The blog outlines the importance of flu vaccines for older adults and strategies to increase uptake in your clinic.
The Disproportionate Burden of Influenza in Older Adults
Adults aged ≥65 years are especially susceptible to severe influenza symptoms and serious complications due to factors such as chronic comorbidities and age-related decline in immune function (immunosenescence). Statistics underscore this burden:
- Older adults account for the majority of influenza-associated hospitalizations, ICU admissions, and deaths annually.
- In Canada, 45% of influenza-associated hospitalizations during the 2023-2024 season occurred in adults ≥65 years, and over 80% of overall influenza-associated deaths in A(H3N2) dominant seasons were in this age group.
- There’s a 7.31 times increased risk of acute myocardial infarction among adults >65 years during the 7 days after laboratory-confirmed influenza infection.
- Long-term care residents aged 66-85 years face a 4.6 times greater risk of influenza-related hospitalization compared to community residents in the same age range.
Given these risks, optimizing influenza protection in older adults is a critical public health priority.
Prioritizing Enhanced Influenza Vaccines
National and international recommendations increasingly favour enhanced influenza vaccines for adults aged ≥65 years due to their superior immunogenicity and improved efficacy/effectiveness compared to standard-dose vaccines. When available, the National Advisory Committee on Immunization (NACI) recommends offering these options over others:
- High-Dose Inactivated Influenza Vaccine (IIV-HD): Contains four times the amount of hemagglutinin antigen found in standard-dose vaccines, designed to elicit a stronger immune response.
- Adjuvanted Inactivated Influenza Vaccine (IIV-Adj): Includes an adjuvant (MF59, an oil-in-water emulsion of squalene oil) that boosts the magnitude and breadth of the immune response.
- Recombinant Influenza Vaccine (RIV): Produced using recombinant technology, it contains three times more hemagglutinin than standard-dose vaccines and eliminates the risk of viral mutations associated with egg-based production, potentially reducing antigenic mismatch.
While IIV-HD has the most extensive body of supporting evidence, followed by IIV-Adj and RIV, these enhanced vaccines are generally well-tolerated with similar safety profiles to standard-dose vaccines. If a preferred product is not available, any available age-appropriate influenza vaccine should be utilized.
Understanding the Evidence: RCTs and Real-World Data
Clinical decisions are best informed by a comprehensive understanding of different types of evidence:
- Randomized Controlled Trials (RCTs): Considered the “gold standard” for determining efficacy due to controlled settings and randomization that minimizes bias. However, their strict inclusion criteria can limit how well results apply to diverse real-world populations.
- Real-World Evidence (RWE): Derived from observational data (e.g., electronic medical records, health care registries), RWE provides insights into the effectiveness of interventions in routine clinical practice. It offers greater external validity by reflecting heterogeneous patient populations and is valuable for long-term surveillance, though it may be subject to unmeasured confounding factors.
Both RCTs and RWE are essential for a holistic understanding of vaccine performance and guiding clinical practice.
Practical Strategies for Maximizing Vaccination Rates
Primary care clinicians and pharmacists are key players in increasing influenza vaccination rates. Effective strategies include:
- Proactive Identification: Identify high-risk individuals through patient profiles, incoming referrals, and prescription reviews.
- Direct Offering: Offer influenza vaccination on-site to individuals who have not yet received their seasonal shot.
- Patient-Centered Communication (The SHARE Method): When addressing vaccine hesitancy, employ a structured approach:
- S (Share): Explain why the vaccine is right for the individual based on their age, health status, and risk factors.
- H (Highlight): Share positive experiences with influenza vaccines to reinforce benefits.
- A (Address): Answer questions and concerns about safety and effectiveness using plain, understandable language.
- R (Remind): Emphasize how the vaccine protects them and their loved ones from severe complications.
- E (Explain): Discuss the potential costs of getting influenza (health, financial, time lost) and the risk of transmission.
- Concurrent Administration: Capitalize on opportunities to administer influenza vaccines simultaneously with other recommended vaccines, such as COVID-19 and pneumococcal vaccines, to enhance comprehensive protection.
- Community Engagement: Partner with local public health departments and non-profit advocacy groups to promote vaccination awareness among high-risk groups.
- Optimizing Workflow: For pharmacies, implementing strategies like scheduled clinics, accommodating walk-ins, and engaging all staff members can significantly improve vaccine accessibility and uptake. Consider proactive outreach, even for patients receiving medication deliveries.
By understanding the unique vulnerabilities of older adults, embracing enhanced vaccine options, utilizing evidence effectively, and adopting proactive communication and administrative strategies, pharmacists can significantly contribute to safeguarding this critical population against the burden of influenza.
Learn more in this 30-minute CCCEP-accredited course, Using Clinical Data to Combat Influenza in Older Adults. Start today and be prepared for the upcoming flu season.
