What is whooping cough?

Whooping cough (pertussis) is a highly contagious bacterial infection of the upper respiratory system-specifically, the area where the nasal passages meet the back of the throat (nasopharynx). The infection causes irritation in breathing passages, resulting in severe coughing spells. The illness can have three distinct stages and can last months.

Complications like pneumonia can result from whooping cough. These kinds of problems can be very serious in young children, especially babies who are born early or who have not been immunized. Older adults are also more likely than other people to have problems caused by whooping cough.

What causes whooping cough?

Whooping cough is caused by infection with Bordetella pertussis or B. parapertussis bacteria. The infection easily spreads from person to person through respiratory secretions or mucus, which can be emitted during coughing or sneezing. The incubation period is about 7 to 14 days, meaning that symptoms start about 1 to 2 weeks after exposure to the bacteria.

Getting immunized helps prevent whooping cough infection and the spread of the disease. The whooping cough vaccine is recommended for children, adolescents, and adults. Routine immunization especially helps babies, older adults, and others who are at high risk for problems caused by whooping cough. Caregivers who never got immunized-and may not even know that they have the illness-can spread whooping cough to babies and other people who aren’t immunized.

You can get whooping cough more than once. After being immunized or after recovering from whooping cough infection, you are temporarily protected from getting a severe form of the disease again. But this protection does not last. You can get another whooping cough infection years later. You can reduce your risk of infection by getting the recommended booster shot with the pertussis vaccine.

What are the symptoms?

Symptoms of whooping cough typically last 6 to 10 weeks (but may last longer) and can occur in three stages.

• Stage 1: Coldlike symptoms-such as sneezing, runny nose, mild coughing, watery eyes, and sometimes a mild fever-last from several days to 2 weeks. An infected person is most contagious during this stage.
• Stage 2: Coldlike symptoms fade, but the cough gets worse. It changes from a dry, hacking cough to bursts of uncontrollable, often violent coughing. During a coughing episode, it may be temporarily impossible to take a breath because of the intensity and repetition of coughs. When finally able to breathe, the person may take in a sudden gasp of air through airways narrowed by inflammation, and this sometimes causes a whooping noise. Vomiting and severe exhaustion often follow a coughing spell. But between coughing episodes, the infected person often appears normal. This is the most serious stage of whooping cough, usually lasting from 2 to 4 weeks or longer.
• Stage 3: Although the person improves and gains strength, the cough may become louder and sound worse. Coughing spells may occur off and on for weeks to months and may flare up if a cold or other upper respiratory illness develops. This final stage may last longer in people who have never received the whooping cough vaccine.