Pertussis
Whooping cough
Pertussis is a highly contagious bacterial disease that causes uncontrollable, violent coughing. The coughing can make it hard to breathe. A deep "whooping" sound is often heard when the person tries to take a breath.
Causes
Pertussis, or whooping cough, is an upper respiratory infection. It is caused by the Bordetella pertussis bacteria. It is a serious disease that can affect people of any age and cause permanent disability in infants, and even death.
When an infected person sneezes or coughs, tiny droplets containing the bacteria move through the air. The disease is easily spread from person to person.
The symptoms of infection often last 6 weeks, but it can last as long as 10 weeks.
Symptoms
Initial symptoms are similar to the common cold. In most cases, they develop about a week after exposure to the bacteria.
Severe episodes of coughing start about 10 to 12 days later. In infants and young children, the coughing sometimes ends with a "whoop" noise. The sound is produced when the person tries to take a breath. The whoop noise is rare in infants under 6 months of age and in older children or adults.
Coughing spells may lead to vomiting or a short loss of consciousness. Pertussis should always be considered when vomiting occurs with coughing. In infants, choking spells and long pauses in breathing are common.
Other pertussis symptoms include:
- Runny nose
- Low grade fever, usually 100.4°F (38.9°C) or lower
- Diarrhea
Exams and Tests
The initial diagnosis is most often based on the symptoms. However, when the symptoms are not obvious, pertussis may be hard to diagnose. In very young infants, the symptoms may be caused by pneumonia instead.
To know for sure, your child's health care provider may take a sample of mucus from their nose. The sample is sent to a lab and tested for pertussis. While this can offer an accurate diagnosis, the test takes some time. Most of the time, treatment is started before the results are ready.
Some people may have a complete blood count that shows large numbers of lymphocytes.
Treatment
If started early enough, antibiotics such as erythromycin can make the symptoms go away more quickly. Unfortunately, most people are diagnosed too late, when antibiotics aren't very effective. However, the medicines can help reduce the person's ability to spread the disease to others.
Infants younger than 18 months need constant supervision because their breathing may temporarily stop during coughing spells. Infants with severe cases should be hospitalized.
An oxygen tent with high humidity may be used.
Fluids may be given through a vein if coughing spells are severe enough to prevent the person from drinking enough fluids.
Sedatives (medicines to make you sleepy) may be prescribed for young children.
Cough mixtures, expectorants, and suppressants are most often not helpful. These medicines should not be used.
Outlook (Prognosis)
In older children, the outlook is most often very good. Infants have the highest risk for death, and need careful monitoring.
Possible Complications
Complications may include:
- Pneumonia
- Convulsions
- Seizure disorder (permanent)
- Nosebleeds
- Ear infections
- Brain damage from lack of oxygen
- Bleeding in the brain (cerebral hemorrhage)
- Intellectual disability
- Slowed or stopped breathing (apnea)
- Death
When to Contact a Medical Professional
Contact your provider if you or your child develops symptoms of pertussis.
Call 911 or the local emergency number or get to an emergency room if the person has any of the following symptoms:
- Bluish skin color, which indicates a lack of oxygen
- Periods of stopped breathing (apnea)
- Seizures or convulsions
- High fever
- Persistent vomiting
- Dehydration
Prevention
DTaP vaccination, one of the recommended childhood immunizations, protects children against pertussis infection. DTaP vaccine can be safely given to infants. Five DTaP vaccines are recommended. They are most often given to children at ages 2 months, 4 months, 6 months, 15 to 18 months, and 4 to 6 years.
The TdaP vaccine should be given at age 11 or 12.
During a pertussis outbreak, unimmunized children under age 7 should not attend school or public gatherings. They should also be isolated from anyone known or suspected to be infected. This should last until 14 days after the last reported case.
It is also recommended that adults age 19 and older receive 1 dose of the TdaP vaccine against pertussis.
TdaP is especially important for health care professionals and anyone having close contact with a baby younger than 12 months old.
Pregnant women should get a dose of TdaP during every pregnancy between 27 and 36 weeks of pregnancy, to protect the newborn from pertussis.
References
Centers for Disease Control and Prevention website. Whooping cough (pertussis): about whooping cough. www.cdc.gov/pertussis/about/index.html. Updated November 26, 2025. Accessed February 20, 2026.
Issa AN, Wodi AP, Moser CA, Cineas S. Advisory committee on immunization practices recommended immunization schedule for children and adolescents aged 18 years or younger - United States, 2025. MMWR Morb Mortal Wkly Rep. 2025;74(2):26-29. PMID: 39819853 pubmed.ncbi.nlm.nih.gov/39819853/.
Souder EE, Long SS. Pertussis (Bordetella pertussis and Bordetella parapertussis). In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 243.
Wodi AP, Issa AN, Moser CA, Cineas S. Advisory committee on immunization practices recommended immunization schedule for adults aged 19 years or older - United States, 2025. MMWR Morb Mortal Wkly Rep. 2025;74(2):30-33. PMID: 39820474 pubmed.ncbi.nlm.nih.gov/39820474/.
Review Date: 7/1/2025
Reviewed By: Charles I. Schwartz, MD, FAAP, Clinical Assistant Professor of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, General Pediatrician at PennCare for Kids, Phoenixville, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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