It's been known for ages that the flu match may not be great and there's less natural immunity about.
www.walesonline.co.uk/news/uk-news/flu-significant-public-health-concern-21815243
It comes as England’s Deputy Chief Medical Officer Professor Jonathan Van-Tam warned that influenza is a "significant public health concern" this winter - because our natural immunity has been lowered by two years of lockdowns, social distancing, increased hand-washing and mask-wearing.
On Friday, Professor Van-Tam said: "Not many people got flu last year because of Covid-19 restrictions, so there isn’t as much natural immunity in our communities as usual.
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UK Health Security Agency chief executive Dr Jenny Harries also said there is lower immunity to flu this year.
Asked how worried the public should be about flu this winter, she told Sky’s Trevor Phillips On Sunday: “We should be worried about flu each winter. I think people still don’t realise it can be a fatal disease. Recent studies suggest that about 25% of us don’t actually understand that. On average, over the last five years, about 11,000 people have died with flu-related conditions.
“So I think it’s an uncertain winter ahead – that’s not a prediction it’s an uncertain feature – but we do know that flu cases have been lower in the previous year so immunity and the strain types are a little more uncertain.”