Seasonal influenza (flu)

What is influenza (Flu)?

Influenza or 'flu' is a respiratory illness caused by influenza virus. Symptoms may include:

  • Headache
  • Fevenr
  • Cough
  • Sore throat
  • Aching muscles and joints.

Flue is most common during the winter months and usually peaks between December and March in the Northern Hemisphere.

Types of influenza:

There are two main types of influenza that cause illness:

  • Influenza A - usually causes more severe illness
  • Influenza B - can also cause infection, but is generally milder

The influenza virus changes constantly, with new strains and variants emerging every year. Because of this, annual vaccination is recommended to provide best protection.

Who is at higher risk from Flu?

For most people, flu is unpleasant, but not serious.  However, some people are more at risk of sever illness and complications

You are considered 'at risk’ if you are :

  • pregnant (at any stage of pregancy)
  • aged 50 or over on 31 March 2024 (even if you feel fit and healthy)
  • a child or adult with certain medical conditions, including:
    • chronic chest condition (such as asthma)
    • chronic heart condition
    • chronic liver disease
    • chronic kidney disease
    • diabetes
    • lowered immunity due to disease or treatment such as steroids or cancer therapy (people living in the same house as someone with lowered immunity may also need to be vaccinated)
    • a chronic neurological condition (such as stroke, multiple sclerosis, cerebral palsy, or hereditary and degenerative diseases of the central nervous system or muscles)
    • serious medical condition (check with your doctor if you are unsure
  • a child who has previously been admitted to hospital with a chest infection
  • a child attending schools for children with severe learning difficulties
  • living in a residential or nursing home
  • a main carer for an older or disabled people

How to get a free flu vaccine

If you are in a an 'at risk' group, you are eligible for a free flu vaccine on the HSC (NHS) through your local GP practice.

Where to get vaccinated

  • Adults and eligible children - Contact your GP practice to book your flu vaccination

  • Primary school children and Year 8 pupils - Will be offered the flu vaccine at school

  • Children aged 2-4 years - Eligible for a free flu vaccine through their GP practice

Children are also vaccinated to help prevent the spread of flu to vulnerable people.

Flu complications

Flu can lead to serious complications, including:

  • Bronchitis

  • Secondary bacterial pneumonia.

These complications may require hospital treatment and can be life threatening - especially for the elderly, those with asthma, and individuals in poor health. 

Each year, around 8,000 people die in the UK from flu, with higher numbers in severe flu seasons.

Flu surveillance and further information

Influenza weekly surveillance bulletins
Please click here to view all recent surveillance bulletins from the PHA.

Other key links 
Public Health England: Seasonal influenza: guidance, data and analysis

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