The New Link Between Working Age Health and Flu Prevention

Flu vaccination plays a clear role in preventing influenza infection and reducing severe illness. New research has also created interest in the possible long term health benefits of flu vaccines, including brain health. Even so, the findings help explain why flu prevention matters for long term wellbeing and why employers can benefit from strong vaccination coverage in the workplace.

What the research says about flu vaccination and dementia risk

A large 2022 US claims-based cohort study compared adults aged 65 and over who received an influenza vaccine with similar adults who did not. Over about four years of follow up, the study reported that 5.1 percent of vaccinated people developed Alzheimer’s disease compared with 8.5 percent of unvaccinated people. The authors reported an estimated relative risk of 0.60 and a number needed to treat of 29 over the follow up period. These results suggest an association between flu vaccination and a lower observed risk of Alzheimer’s disease in that population, but the study design cannot prove cause and effect.

Other reporting has grouped this research with findings on shingles and pneumonia vaccines, which have also shown links with a lower risk of dementia in some observational studies. These reports help raise awareness, but it is important that they do not confirm prevention.

What this means for keeping employees healthy long term

The proven benefits remain short term and clear, fewer influenza infections, fewer severe cases, and lower risk of hospitalisation. The possible longer term benefits, such as a lower observed risk of dementia in some older adult studies, remain an emerging area of research.

For employers, the practical value is strong. If vaccination reduces severe illness and complications, employees return to normal sooner and teams face fewer gaps in staffing. If future research continues to support longer term benefits, that would also support healthy ageing across the workforce over time, especially as many workplaces employ people in their 50s and 60s, and many employees care for older family members.

A healthier workforce supports productivity and lowers the operational costs that come with unplanned absenteeism.

Why organisations should think beyond sick leave

There is also growing interest in longer term health links beyond the brain. A 2025 review discussed how influenza infection can trigger inflammation that may contribute to cardiovascular events in higher risk people, and it reviewed influenza vaccination as a preventive strategy in this wider context. The take home message for workplaces stays simple, preventing flu can reduce more than short term disruption.

Influenza prevention is not only about fewer winter sick days. Flu can cause severe illness, particularly in older adults and those with long term conditions. Protecting employees also reduces the chance of bringing influenza home to vulnerable family members, including older parents, grandparents, and young children.

What employers can do now practical steps for winter protection

Workplace flu prevention works best when it is easy, early, and well communicated.

• Run onsite vaccination clinics, so staff can get vaccinated at work with minimal disruption.
• Provide flu vouchers, so staff who miss the clinic, work remotely, or travel can still get vaccinated at a pharmacy or medical centre.
• Communicate early, with simple messages on vaccination dates, consent forms, and what to expect on the day.
• Keep the message accurate, the main proven benefit is preventing flu and reducing severe outcomes and positive heart health benefits, while long term links like brain health remain an area of active study.

These steps help employers protect staff, support whānau wellbeing, and reduce winter disruption, with the added benefit that research continues to explore the wider health effects of vaccination.

Sources

• Health New Zealand, Te Whatu Ora. (2026, January 3). Adult immunisations.
• Medsafe. (2025, November 10). Influenza vaccine composition.
• Pharmac. (2024, October 16). Influenza vaccine (flu jab), Pharmac’s role.
• Bukhbinder, A. S., Ling, Y., Hasan, O., Jiang, X., Kim, Y., Phelps, K. N., Schmandt, R. E., Amran, A., Coburn, R., Ramesh, S., Xiao, Q., & Schulz, P. E. (2022). Risk of Alzheimer’s disease following influenza vaccination, A claims based cohort study using propensity score matching. Journal of Alzheimer’s Disease, 88(3), 1061–1074.
• Appel, A. M., Janbek, J., Jensen-Dahm, C., Laursen, T. M., & Waldemar, G. (2024). The effect of influenza vaccination on the rate of dementia amongst older adults. European Journal of Neurology, 31(12), e16489.
• Fröbert, O., Pedersen, I. B., Hjelholt, A. J., Erikstrup, C., & Cajander, S. (2025). The flu shot and cardiovascular protection, Rethinking inflammation in ischemic heart disease. Atherosclerosis, Advance online publication, 120405.
• Bukhbinder et al. 2022, Risk of Alzheimer’s Disease Following Influenza Vaccination, claims based cohort study, adults 65+.