Pertussis ( Whooping Cough )

Symptoms and Causative Agent

Pertussis, also known as whooping cough, is an extremely contagious disease caused by the Bordetella pertussis bacterium. These bacteria produce toxins that paralyze parts of respiratory cells, leading to inflammation in the respiratory tract.

The incubation period for pertussis is generally between 7-10 days long, but can last more than a month. After symptoms first appear, the disease can take anywhere from weeks to months to fully run its course.

Initial symptoms include runny nose, sneezing, and a mild cough, which may seem like a typical cold. A mild fever also generally occurs. However, the cough slowly becomes more severe. Eventually the patient experiences bouts of rapid coughing followed by the “whooping” sound that gives the disease its common name as they try to inhale. While the coughing fit is occurring, the patient may turn blue.

While symptoms may be less severe for adults, pertussis can be extremely dangerous for infants and young children.

In between bouts of coughing, the person typically does not appear to be ill.


The bacteria that cause pertussis are spread in the air in droplets created when a sick person coughs or sneezes. People nearby can become infected by breathing in the droplets. 

Although cases of pertussis have dropped dramatically in the United States since the introduction of the pertussis vaccine, the disease has caused widespread outbreaks in recent years. In 2012, nearly 50,000 cases of pertussis were reported in the United States, the most cases since 1955. Twenty pertussis deaths were reported in 2012. Fifteen of those deaths occurred in infants too young to have received the vaccine.

Pertussis also remains a major problem in the developing world. The World Health Organization estimates that pertussis caused 89,000 deaths worldwide in 2012.

The tendency of pertussis to be milder in adults, sometimes escaping diagnosis, further complicates disease transmission. The coughing associated with the disease may be mild enough in an adult case to mistaken as a simple cold. The adult, however, will still be contagious and can easily spread the disease to infants too young to be vaccinated, or to individuals whose immunity has waned.

Treatment and Care

Treatment for pertussis is generally limited to supportive care. Antibiotics are sometimes used; however, this is primarily done to remove the Bordetella pertussis bacteria from an infected patient’s secretions, thus reducing her ability to infect others. Antibiotic treatment is unlikely to affect the course of the illness unless administered very early on.

Antibiotics may be given to individuals in contact with the patient in order to prevent infection.


Infants younger than six months of age are particularly at risk for complications and death from pertussis. Complications include pneumonia (bacterial or viral), seizures, ear infections, and dehydration, among others; in adults, rib fracture from coughing is also possible.

The most common of these complications in infants is B. pertussis pneumonia, which accompanies almost all deaths from pertussis.

Available Vaccines and Vaccination Campaigns

Immunization against pertussis is available for children via the combination DTaP (diphtheria, tetanus, and acellular pertussis) vaccine. The DTaP vaccination replaced the previously used DTP shot, which protected against the same three diseases but used a whole-cell preparation in the pertussis component—that is, it contained inactivated, but complete, Bordetella pertussis bacteria. For the DTaP combination vaccine, the whole-cell preparation was removed; “aP” stands for “acellular pertussis.” This vaccine provides protection against the disease by using only pieces of the pertussis bacteria, which results in fewer side effects than the whole-cell preparation.

A similar combination vaccine called Tdap offers booster protection against tetanus, diphtheria, and pertussis for adolescents and adults in certain situations.

U.S. Vaccination Recommendations

Immunization against pertussis is included on the U.S. childhood immunization schedule as part of the combined DTaP shot. This vaccine is given in several doses, with the first recommended at two months of age, and the last between age four and six years.

A booster dose of pertussis vaccine via the Tdap combined immunization is recommended for adolescents and also for adults over age 19. Pregnant women are recommended to get a booster dose of Tdap during the third trimester of pregnancy. Your doctor can tell you more about when to consider a Tdap booster.


Centers for Disease Control and Prevention. 2013 Final Pertussis Surveillance. (134 KB). Accessed 01/25/2018.

CDC. Pertussis. Epidemiology and Prevention of Vaccine-Preventable Diseases. Atkinson, W., Wolfe, S., Hamborsky, J., McIntyre, L. eds. 13th ed. Washington DC: Public Health Foundation, 2015. (730 KB). Accessed 01/25/2018.

CDC. Pertussis cases by year, 1922-2015. Accessed 01/25/2018.

CDC. Pertussis: Summary of vaccine recommendations. Accessed 01/25/2018.

CDC. Vaccine information sheet (VIS), DTaP. Accessed 01/25/2018.

Paddock, C.D., Sanden, G.N., Cherry, J.D., et. al. Pathology and pathogenesis of fatal Bordetella pertussis infection in infants. Clinical Infect Dis. 2008; 328-38.

CDC. Pertussis vaccination: Use of acellular Pertussis vaccines among infants and young children recommendations of the Advisory Committee on Immunization Practices (ACIP). (1997) Morbidity and Mortality Weekly Report, 46(RR-7);1-25. Accessed 01/25/2018.

World Health Organization. Pertussis. Immunization, Vaccines, and Biologicals. Accessed 01/25/2018.

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Last update 25 January 2018

Timeline Entry: 7/9/2010

California Pertussis Cases Increase 418% from 2009

In its July 9, 2010 Morbidity and Mortality Weekly Report (MMWR), the Centers for Disease Control and Prevention noted that pertussis (whooping cough) cases reported to the California Department of Health between January 1 and June 30 had increased by 418% over those reported during the same period in 2009. Of these, 89% of cases were among infants less than six months of age, who are too young to be fully immunized against pertussis. As of June 30, five deaths had been reported from pertussis, all among infants less than two months of age.

The CDC urged individuals to be sure that they were up to date on their pertussis immunizations, noting that while whooping cough is generally not as severe for adults, they are still contagious and can pass the disease on to children who are not yet fully immunized. Pertussis immunization is available as part of the DTaP vaccine for children and the Tdap booster vaccine for adults and adolescents.

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Assessment Questions

Pertussis is caused by __________.

  • bacteria
  • viruses
  • fungi
  • none of the above

True or false? Pertussis symptoms usually go away after a few days.

  • True
  • False

Pertussis is especially dangerous for __________.

  • teenagers
  • adults
  • infants
  • the very old
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