Whooping Cough (Pertussis): Symptoms, Risks and Vaccination

Last updated October 28, 2026

Whooping cough, also called pertussis, is a very contagious respiratory illness. It can make people of any age sick, but it is most dangerous for babies.

The illness often starts like a common cold. Unlike a cold, the cough can go on for weeks or even months. Vaccination is the best way to prevent it.

What Causes Whooping Cough?

Whooping cough is caused by a bacterium called Bordetella pertussis. The disease is found only in humans.

The bacteria attach to the cilia, the tiny hair-like structures that line part of the upper airway. They release toxins that damage the cilia and make the airways swell.

How Whooping Cough Spreads

The bacteria spread easily from person to person through the air. When someone with whooping cough coughs or sneezes, they release small particles that carry the bacteria. People nearby can breathe them in.

Spread is most likely when people spend a lot of time together or share the same breathing space, such as in a household.

  • People can spread the bacteria from the start of their symptoms and for at least 2 weeks after the cough begins.
  • Some people have mild symptoms and do not know they have whooping cough, but they can still pass it on.
  • Many babies who get whooping cough catch it from older brothers or sisters, parents or caregivers who do not know they are sick.

Antibiotics taken early in the illness may shorten the time a person is contagious.

Symptoms of Whooping Cough

Symptoms usually appear 5 to 10 days after exposure. Sometimes they take as long as 3 weeks to develop.

Early Symptoms

The early stage looks like a common cold and usually lasts 1 to 2 weeks. Symptoms include:

  • A runny or stuffy nose.
  • A low-grade fever.
  • A mild cough that comes and goes.

Many babies with whooping cough do not cough at all. Instead, they may have apnea, which is a life-threatening pause in breathing. A baby may turn blue or struggle to breathe.

Later Symptoms

One to 2 weeks after the first symptoms, rapid and violent coughing fits can start. These fits usually last 1 to 6 weeks but can last up to 10 weeks. The cough often gets worse as the illness goes on.

Coughing fits can cause a person to:

  • Make a high-pitched “whoop” when breathing in after a fit.
  • Vomit during or after a fit.
  • Feel very tired after a fit, while seeming well between fits.
  • Have trouble sleeping.
  • Struggle to breathe.
  • Break a rib.

Recovery can be slow. The cough becomes milder over time, but coughing fits can come back with other respiratory infections, even months later.

See a healthcare provider if you or your child are coughing violently. Get care right away for any breathing difficulty.

Who Is Most at Risk?

Babies younger than 1 year old have the greatest risk of getting whooping cough and of having severe complications. People with some health conditions, such as a weakened immune system or moderate to severe asthma, are also at higher risk of severe illness.

According to the CDC, about 1 in 3 babies younger than 1 year old who get whooping cough need care in the hospital. Among babies who are treated in the hospital:

  • About 2 in 3 (68%) have apnea.
  • About 1 in 5 (22%) get pneumonia.
  • About 1 in 50 (2%) have convulsions.
  • About 1 in 150 (0.6%) get encephalopathy, a disease of the brain.
  • About 1 in 100 (1%) die from complications.

Teens and adults can also have complications, such as pneumonia. These are usually less serious, especially in people who have been vaccinated.

Diagnosis and Treatment

Whooping cough can be hard to diagnose because early symptoms look like other respiratory illnesses. Healthcare providers use the person’s symptoms, a physical exam and laboratory tests, such as a test of a mucus sample from the back of the throat or a blood test.

Providers usually treat whooping cough with antibiotics. Early treatment, before the coughing fits begin, is important and may make the infection less serious. People with serious symptoms may need treatment in the hospital.

People who have been around someone with whooping cough may be given antibiotics to help prevent illness. A healthcare provider or the health department usually decides who should get them.

Whooping Cough Vaccines

The best way to prevent whooping cough is to get vaccinated. The CDC recommends whooping cough vaccination for everyone: babies and children, preteens and teens, pregnant women and adults.

Whooping cough vaccines are combined with protection against diphtheria and tetanus. There are 2 types:

  • DTaP is for babies and young children. Children get up to 5 doses.
  • Tdap is for people 7 years and older. It is given to preteens and teens, during pregnancy, as a booster for adults, and to people who were never vaccinated.

How Well the Vaccines Work

The vaccines work well, but protection fades over time. CDC figures show:

  • For children who get all 5 doses of DTaP, the vaccine protects nearly all of them (98 in 100) within a year of the last dose, and about 7 in 10 five years after the last dose. Most of the other 3 in 10 are partly protected and less likely to get seriously ill.
  • Tdap protects about 7 in 10 people in the first year, and about 3 or 4 in 10 people four years later.
  • Tdap during pregnancy protects more than 3 in 4 babies younger than 2 months old from whooping cough, and about 9 in 10 babies from being hospitalized with it.

People who are vaccinated and still get whooping cough usually have a milder illness.

Side Effects

Most people have no serious problems after vaccination. Mild reactions are common and usually go away within a few days. They include soreness or swelling where the shot was given, a mild fever, tiredness and a poor appetite. Serious reactions, such as seizures or a very high fever after DTaP, are much less common.

Talk with a vaccine provider about your vaccination history, any allergies and any past reactions to a vaccine.

Why Prevention Matters

Whooping cough has not gone away. In the United States it is still a common disease, with peaks in reported cases every few years. Having whooping cough once does not give lifelong protection, so vaccination is important even for people who have had the disease.

Keeping up with recommended doses protects you and helps protect the babies around you, who are too young to be fully vaccinated. To learn how vaccination fits into wider public health planning, read about the economics of vaccination.

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