New Research Suggests High-Dose Flu Vaccine May Reduce Alzheimer’s Risk
Recent research has highlighted a potential link between high-dose flu vaccines and a reduced risk of developing Alzheimer’s disease. This discovery could have significant implications for older adults, particularly as they age and face increased health risks.
The study, which involved nearly 200,000 adults aged 65 and over, found that those who received a high-strength flu jab had a 55 per cent lower risk of developing Alzheimer’s compared to those who received the standard dose, which showed a 40 per cent reduction. These findings were published in Neurology and contribute to growing evidence that routine vaccinations may play a role in protecting the brain as people grow older.
While the exact mechanism is not yet fully understood, scientists believe that the benefits of vaccination come from its ability to support the aging immune system. As people get older, their bodies become less effective at fighting infections and managing inflammation, which can lead to chronic conditions such as dementia, cancer, and heart disease.
How Vaccines Might Help Protect the Brain
Vaccines, including the high-dose flu jab, may help strengthen the immune system and reduce inflammation, potentially lowering the risk of cognitive decline. This is especially relevant for individuals aged 65 and over, as their immune systems are more vulnerable to weakening.
Dr Paul Schulz, a professor of neurology at McGovern Medical School at UTHealth Houston, explained that by age 65, the immune system becomes less effective at combating infections. This is why high-dose vaccines are recommended for this age group. Previous research from his team suggested that any flu shot could lower Alzheimer’s risk, but this new study shows that higher doses may offer even greater protection.
Dr Avram Samuel Bukhbinder, a neurology fellow at Massachusetts General Hospital, added that selecting the high-dose vaccine could be an easy, safe, and widely available way to help protect the brain as we age.
Flu Vaccination in the UK
In the UK, more potent flu vaccines are already part of routine care for older adults. The Joint Committee on Vaccination and Immunisation (JCVI) recommends ‘enhanced’ vaccines for those aged 65 and over to counteract the natural weakening of the immune system.
Options include:
- High-dose inactivated influenza vaccine (IIV-HD) – such as Efluelda, which is four times stronger than standard vaccines.
- Adjuvanted vaccine (Fluad) – contains an added ingredient to boost the immune response and provide longer-lasting protection.
- Recombinant vaccine (Supemtek) – an egg-free jab considered equivalent in providing enhanced protection.
These vaccines are offered free on the NHS to those aged 65 and over, typically from October each year.
Observational Study and Limitations
It is important to note that the study was observational, meaning it identified an association rather than proving causation. Other factors, such as overall health and lifestyle, could also influence the results. However, the findings highlight the added benefit of the high-dose shot, not just for preventing influenza but also for reducing the risk of Alzheimer’s.
In England, flu vaccine uptake for those aged 65 and over is consistently high, with 74.9 per cent vaccinated in the 2024–25 season. While this is close to the 75 per cent target set by the World Health Organisation, uptake in 2023 was higher at 79 per cent.
Understanding Alzheimer’s Disease
Alzheimer’s is the most common form of dementia in the UK, accounting for 60 to 80 per cent of cases. The progressive disorder is caused by abnormal protein build-up in the brain, known as plaques and tangles, which gradually destroy brain cells. Early detection and management are crucial in helping those affected maintain their quality of life.
For those seeking further information or support, resources such as the Alzheimer’s Society’s Dementia Support Line can provide valuable guidance. Additionally, tools like the symptoms checker can help identify early signs of dementia, enabling timely intervention.
