The NHS is warning that the winter flu has started 6-8 weeks early this year, and this is partly down to a new mutation in the H3N1 flu virus. It could be the worst flu season for a decade or more.
The bottom line is basically that if you’re eligible, or can afford to pay, please get your flu jab. It’s the best protection there is, and even if the vaccine provides less protection than is ideal it should still provide protection against severe illness.
There’s a BBC report at https://www.bbc.co.uk/news/articles/c2dr8gzdz1wo.