Flu season has begun, and Belgium is once again emphasizing the importance of vaccination for older adults aged 65 and up.
Recent data from Healthy Belgium show that 540,000 people, roughly 5% of Belgium’s population, were affected by influenza-like illnesses during the 2024-2025 flu season.
While older people aren’t usually the largest age demographic affected, they are the most vulnerable to serious infections. The Superior Health Council of Belgium’s extensive 2026-2027 Influenza report states that Belgians aged 65 and older have the highest influenza-related hospitalization rate and account for nearly two-thirds of all flu-related deaths.
Sciensano found that during the 2024-2025 flu season, Belgium recorded 2,872 excess deaths, or a 9.3% excess mortality rate, which steadily increased with age among infected people. Across Belgium, Brussels had an excess mortality rate roughly 4% higher than any other region at 13.6%.
Updated vaccination recommendations
Earlier this year, Belgium's Superior Health Council updated its vaccination recommendations for this flu season. They now recommend that older adults take one of two flu vaccinations, either a high-dose vaccine that contains four times the amount of influenza antigen, or an adjuvanted vaccine that stimulates the immune response beyond the antigen alone. Both aim to at least partly compensate for the reduced immune response that occurs with ageing and were found to be significantly more effective than the standard flu shot.
However, a standard flu shot is still recommended for people under 65, though the Belgian Centre for Pharmacotherapeutic Information (CBIP) notes that individuals with kidney disease should take the high-dose rather than the adjuvanted vaccine.
It is strongly recommended to consult a healthcare professional before requesting a certain vaccine, as individual circumstances may affect which vaccine is recommended.
The Council’s full list of recommended vaccines for different ages can be found here.
Dangers with age
As people age, their immune systems typically respond less effectively to infection and vaccination. The flu, in particular, can lead to serious complications like pneumonia or worsen an existing chronic illness. In severe cases, complications include inflammation of the heart muscle, respiratory distress and bloodstream infections.
During the 2024–2025 winter, 15% of Belgian patients hospitalised with flu-related respiratory infections developed severe complications. Of these hospitalised patients, four percent died.
These concerns have led EU-wide organizations like the European Health Management Association to promote a 75% vaccination rate goal among older adults and other at-risk groups, though the most recent figures from 2023 show that Belgium is 24% behind this goal.
