Influenza's mortality burden in older people is well established but varies severalfold between seasons, and the estimate depends heavily on the attribution method, since most influenza deaths are certified to something else. RSV's burden in adults was under-recognised until routine testing and modelling studies in the last decade put it in the same range as a moderate influenza season for the over-75s. That recognition led to the first RSV vaccines for older adults, licensed in 2023 and now in national programmes in the UK, the US and several European countries. First-season effectiveness against RSV-related hospitalisation was high in trials and in early observational studies; how far protection lasts into a second and third season is the open question. Influenza vaccine effectiveness remains modest and variable, typically between a third and a half against medically attended illness, depending on the match. Post-pandemic seasons have been irregular in timing and size, which makes the baseline for excess estimates unstable.