Whooping cough (pertussis) is a highly contagious bacterial infection of the lungs and airways.

The condition usually begins with a persistent dry and irritating cough that progresses to intense bouts of coughing. The gasping for breath after one of these coughing bouts causes a distinctive "whooping" noise, which is how the condition gets its name.

Other symptoms include a runny nose, raised temperature and vomiting after coughing.

The coughing can last for around three months (another name for whooping cough is the "hundred day cough").

Read more about the symptoms of whooping cough.

When to see your GP

See your GP as soon as possible if you think you or your child may have whooping cough.

Your GP can usually diagnose the condition by asking about your symptoms and listening to the cough (the whooping cough is very distinctive).

Whooping cough can also be confirmed with:

• a blood test – to test for antibodies to Bordetella pertussis bacteria
• a sample of mucus taken with a swab – to test for Bordetella pertussis bacteria

Whooping cough can be severe in young babies and, in some cases, they may need to be diagnosed and given immediate treatment in hospital.

What causes whooping cough?

Whooping cough is caused by a bacterium called Bordetella pertussis, which infects the lining of the airways, mainly the windpipe (trachea) and the two airways that branch off from it to the lungs (the bronchi).

If the bacteria make contact with your airways, this leads to:

• a build-up of thick mucus – which causes the intense bouts of coughing as your body tries to expel it
• swollen airways – which makes breathing more difficult and causing the "whoop" sound as you gasp for breath after coughing

People with whooping cough are infectious from six days after exposure to the bacteria to three weeks after the "whooping" cough begins.

The bacteria is passed from person to person by infected droplets in the air, spread by coughing and sneezing.

Treating whooping cough

If whooping cough is diagnosed during the first three weeks (21 days) of infection, a course of antibiotics may be prescribed. This is to prevent the infection being passed on to others.

It's important to take steps to avoid spreading the infection to others, particularly babies under six months of age.

Children with whooping cough should be kept away from school or nursery until either:

• five days from the time they start taking antibiotics
• they have had three weeks of intense coughing

The same advice applies to adults returning to work.

As a precaution, household members of someone with whooping cough may also be given antibiotics and a booster shot of the vaccine.

Antibiotics won't usually be prescribed if whooping cough is diagnosed in the later stages of infection (two to three weeks after the onset of symptoms). By this time, you will no longer be infectious. It's also very unlikely that antibiotics will improve your symptoms at this stage.

Your GP will be able to advise you about how to manage the infection at home using some simple self-care measures, such as resting and drinking plenty of fluids to avoid dehydration.

Read more about treating whooping cough.

Babies under a year old are likely to be admitted to hospital as they are most at risk of severe complications, such as serious breathing difficulties.

They will be treated in isolation to prevent the infection spreading and will be given antibiotics into a vein through a drip (intravenously).

Read more about the complications of whooping cough.

Whooping cough vaccination

In the UK, all pregnant women are offered vaccination against whooping cough when they are 28-38 weeks pregnant. Getting vaccinated while you’re pregnant could help to protect your baby from developing whooping cough in its first few weeks of life.

Read more about the whooping cough vaccine in pregnancy.

Children are vaccinated against whooping cough with the 5-in-1 vaccine at two, three and four months of age, and again with the 4-in-1 pre-school booster before starting school at the age of about three years and four months.

Read more about preventing whooping cough.

Although the number of cases of whooping cough has fallen dramatically since vaccination began, it is still possible for children to get the infection, so having the vaccination is vital.

The more people are vaccinated against whooping cough, the less chance of passing on the infection to a young baby, which could cause serious, and possibly fatal, complications.

The effectiveness of the whooping cough vaccination may fade over time, meaning it's possible to develop the condition during adulthood, even if you were vaccinated as a child.

Who is affected?

Due to the success of the NHS vaccination scheme, whooping cough is now uncommon in young children.

Most cases occur in adults whose immunity has faded. In these cases symptoms tend to be less serious, although the persistent cough can be frustrating and unpleasant.

Whooping cough is a cyclical disease with the number of cases thought to peak every three to four years. An outbreak of whooping cough in 2012 meant 9,711 cases were confirmed in England and Wales compared to 4,835 confirmed cases in 2013.

The overall increase in the number of cases of whooping cough is thought to be related to heightened awareness of the disease and more cases being reported.