Seasonal flu immunisation, or the flu jab, is the injection of a vaccine against flu. It gives good protection from flu that lasts for one year.

The flu jab is offered to people in at-risk groups, who are at greater risk of developing serious complications from flu. To stay protected, they need to have it every year.

The vaccine, which is normally available in the autumn, is made from the strains of flu that are expected in winter (see About the vaccine).

How effective is it?

The flu vaccines currently available give 70-80% protection against infection, with flu virus strains closely matching those in the vaccine.

In the elderly, protection against infection may be less, but immunisation reduces the chances of pneumonia, hospital admissions and death from seasonal flu.

Who should have the jab?

For most people, seasonal flu is unpleasant but not serious and they recover within a week.

However, certain people are at greater risk of developing serious complications of flu, such as bronchitis and pneumonia. These may require hospital treatment. A large number of elderly people die from flu every winter.

The seasonal flu vaccine is offered free of charge to these at-risk groups to protect them from catching flu and developing these complications.

Also, this winter, the seasonal flu vaccine will be offered to pregnant women not in the high-risk groups who have not previously been vaccinated against H1N1 (swine) flu.

At-risk groups

It is recommended you have a flu jab if you:

• are 65 or over,
• have a serious medical condition*
• live in a residential or nursing home,
• are the main carer for an elderly or disabled person whose welfare may be at risk if you fall ill,
• are a healthcare or social care professional directly involved in patient care, or
• work with poultry (see below).

* Serious medical conditions such as  include

• chronic (long-term) respiratory disease, such as severe asthma, COPD or bronchitis,
• chronic heart disease, such as heart failure,
• chronic kidney disease,
• chronic liver disease,
• chronic neurological disease, such as Parkinson's disease or motor neurone disease,
• diabetes, or
• a weakened immune system due to disease (such as HIV/AIDS) or treatment (such as cancer treatment.

Also, this year, it is recommended that pregnant women not in the high-risk groups who have not previously been vaccinated against H1N1 flu have the seasonal flu jab.

If you are the parent of a child (over six months) with a long-term condition, speak to your GP about the flu jab. Your child's condition may get worse if they catch flu.

If you are the carer of an elderly or disabled person, make sure they have had their flu jab.

Will it protect against H1N1 (swine) flu?