AT-risk groups have been urged to get their flu jab as soon as possible.
NHS England in Durham, Darlington and Tees said full protection from the jab can take up to two weeks to develop, so people who could be badly affected by the illness should act now.
Dr James Gossow, medical director at Durham, Darlington and Tees NHS England, said: “Flu can knock even the healthiest people off their feet for a couple of weeks, but for some people it can be really serious.”
Those most at risk include pregnant women, people living with a health condition such as severe asthma, chest or heart complaints, and those aged 65 and over.
In recent years, critical care units across the region have been busy with people who should have been vaccinated against flu, but instead ended up seriously ill over Christmas.
Most of these patients would have been eligible for a free flu jab on the NHS.
Dr Gossow added: “I really want to emphasise how severe flu can be. Not only can it stop you caring for your kids and keep you off work, but it can lead to more critical illness and a spell in hospital."
Those eligible can book an appointment with their GP to get their free flu jab.
For more information, speak to your GP or local pharmacist, or visit nhs.uk/flu
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