Whooping cough (also known as pertussis) is a respiratory system infection caused by the bacterium Bordetella pertussis. It is characterized by severe coughing spells that may end in a "whooping" sound when the infected person inhales.
With the number of reported outbreaks of whooping cough on the rise in the United States, the Centers for Disease Control and Prevention (CDC) says there is a need to protect adolescents and adults, as well as children, against this highly contagious respiratory infection. Commonly thought of as a childhood illness, whooping cough actually affects people of all ages.
According to the CDC, 5,000 to 7,000 cases of the illness are reported in the United States each year. Moreover, the condition has been increasingly reported among adolescents and adults in the last several years. This is important because those who have a cough may not realize that they have whooping cough and may be the primary source of infection for infants, who have the greatest risk of dying from the disease.
The cause of the illness is an infection with bacteria. The bacterium that causes whooping cough is called Bordetella pertussis (B. pertussis).
The whooping cough bacteria are spread through direct contact with an infected person's respiratory secretions. They can be passed either through the air or by touching a contaminated surface.
Whooping cough is a highly contagious infection. A person is most likely to transmit the bacteria that cause pertussis when they are experiencing symptoms, especially during the first three weeks of having symptoms.
When a person is infected with Bordetella pertussis, the bacteria begin multiplying within the lungs. The period between infection and the onset of symptoms is called the incubation period. The whooping cough incubation period is commonly 7 to 10 days, with a range of 4 to 21 days, and rarely may be as long as 42 days.
Once whooping cough symptoms begin, there are generally three stages of the illness.
During the first stage, common symptoms are like a cold or flu and can include:
- Sneezing
- Runny nose
- Nasal congestion
- Slight fever
- Dry cough that may get worse at night.
Unlike a cold, the symptoms of whooping cough stick around, and within two weeks, the symptoms get worse. Common symptoms during the next stage can include:
- Fits of coughing that seem to go on and on
- Severe coughing spells that may end in a "whooping" sound when the infected person inhales
- Severe coughing that leads to vomiting, which may make it difficult for a person to eat or drink
- Skin turning blue during coughing episodes.
In the last stage, symptoms gradually improve, disappearing within two to three weeks. However, fits of coughing often return with other respiratory infections for many months after the symptoms improve.
Complications Associated With Whooping Cough
Whooping cough complications are a major concern when a person develops the symptoms of pertussis, especially in children younger than 12 months of age.
Possible complications of whooping cough can include:
- Middle ear infection (otitis media)
- Difficulty breathing
- Less oxygen in the blood (hypoxia)
- Pneumonia
- Seizures
- Encephalopathy
- Malnutrition
- Death.
(Click Whooping Cough Complications to learn more about these potential complications.)
In order to make a diagnosis, your doctor will ask a number of questions, perform a physical exam, and (in some cases) recommend certain tests. As part of diagnosing whooping cough, the doctor will also rule out other causes of possible
whooping cough symptoms, such as the
common cold, flu, and bronchitis.
If you or your child is considered to be at high risk for having whooping cough, your healthcare provider may recommend certain lab tests. Laboratory tests to diagnose whooping cough may be useful with young infants, atypical cases, and cases modified by
pertussis vaccine.
Tests that may be used to help in making a diagnosis include:
- Nose or throat swab
- Blood tests.
(Click Whooping Cough Diagnosis for more information on this topic.)
Whooping cough treatment typically involves antibiotics and supportive care, which involves providing relief of symptoms and complications as the body fights the infection. Preventive treatment is also recommended for any one who comes in close contact with the infected person.
People with whooping cough are advised to avoid contact with others, particularly infants and children.
While there is no lifelong protection against whooping cough, immunization by the
pertussis vaccine is the best whooping cough prevention measure available. Vaccines currently licensed by the Food and Drug Administration (FDA) to prevent whooping cough and reduce related illness and death are available for children up to age 7, and for adolescents between 10 and 18.
The children's vaccine is part of a routine series of childhood immunizations called
DTaP (diphtheria and tetanus toxoids and acellular pertussis vaccine). It is administered in five doses, given at 2, 4, 6, and 15 to 18 months of age, and between ages four and six. All five doses are recommended for maximum protection.
The adolescent vaccine, approved in May 2005, has the same components as the DTaP vaccine for infants and young children, but in reduced quantities.
Infants and Whooping Cough
Infants under the age of 12 months typically become more seriously ill as a result of whooping cough, and they are more likely to have
whooping cough complications and be hospitalized than people in other age groups.
In the 1990s, about two-thirds of infants reported with whooping cough were hospitalized. Infants are more likely to have complications such as pneumonia or convulsions. Infants also are at greatest risk of fatal whooping cough. In recent years, 15 to 21 infant deaths from pertussis have been reported to the CDC annually.
Adults and Whooping Cough
Many people believe that whooping cough is a disease that only affects infants and children. The fact is, whooping cough in adults accounted for more than half of the reported cases of whooping cough in recent years. Yet whooping cough is still underrecognized among adults.
Outbreaks of whooping cough were first described in the sixteenth century, and the organism was first isolated in 1906.
In the twentieth century, pertussis was one of the most common childhood diseases and a major cause of childhood mortality in the United States. Before the availability of
pertussis vaccine in the 1940s, more than 200,000 cases of pertussis were reported annually. Since widespread use of the vaccine began, the incidence of whooping cough has decreased by more than 80 percent compared with the pre-vaccine era.
Statistics on Whooping Cough
Whooping cough remains a major health problem among children in developing countries, with an estimated 285,000 deaths resulting from the disease in 2001.
In the United States, a total of 25,827 cases were reported in 2004, the largest number since 1959.
During 2001 to 2003, the highest average annual whooping cough incidence was among infants younger than one year of age (55.2 cases per 100,000 population) and particularly among children younger than six months of age (98.2 per 100,000 population). In 2002, 24 percent of all reported whooping cough cases were in this age group.
However, in recent years, adolescents (11 to 18 years of age) and adults (20 years and older) have accounted for an increasing proportion of whooping cough cases. During 2001-2003, the annual incidence of pertussis among people aged 10 to 19 years increased from 5.5 per 100,000 in 2001, to 6.7 in 2002, and 10.9 in 2003. In 2004, approximately 60 percent of whooping cough cases occurred in people 11 years of age and older.