Pertussis (Whooping Cough)

Pertussis, also known as whooping cough, is a highly contagious respiratory illness.¹ It is transmitted from person to person through respiratory droplets, like coughing or sneezing. Pertussis is a vaccine-preventable disease.

Pertussis, or whooping cough, is a highly contagious disease involving the upper respiratory tract.¹ It is caused by the bacterium Bordetella pertussis that can be found in the mouth, nose, and throat of an infected person. The bacteria attach to the tiny, hair-like extensions, known as cilia, found in the upper respiratory tract. The bacteria then release toxins which damage the cilia and cause the airways to swell. This disease is only found in humans.¹

Transmission

The bacteria that causes whooping cough spreads from person to person through the air when an infected person coughs or sneezes.¹ As they cough, talk, or sneeze, they exhale tiny particles into the air with bacteria in them, which can then be breathed in by other people.

You Can Be Contagious for Many Weeks Until Treated

People can spread the disease from the time that symptoms start and for several weeks after the coughing begins, or until an appropriate antibiotic treatment is completed.¹ Whooping cough is very serious, especially for infants and young kids.² Some people, particularly older adults and teens, may have mild symptoms and not realize they’re infected. In some cases, older siblings or adults who do not know they have pertussis infect other people, especially infants.¹

Symptoms

Pertussis symptoms typically begin with 5 to 10 days, but it may take up to 21 days (three weeks).³ The early symptoms last for up to two weeks and resemble those of the common cold, including

• Sneezing and runny nose
• Low-grade fever (<100.4 °F)
• A mild cough

Within two weeks, the cough becomes more severe with coughing fits characterized by episodes of many rapid coughs followed by a gasping for air with a high-pitched “whooping” sound.³ This extreme coughing may cause patients to

• Throw up
• Feel very tired, especially right after the fit
• Cough up thick mucus⁴
• Have trouble sleeping at night
• Struggle to breathe
• Break a rib

These coughing fits can last a few weeks to as long as 10 weeks. Completing an appropriate course of antibiotics can significantly shorten the duration of symptoms. The cough tends to get worse as the illness progresses, but it will taper off after treatment.³

Dangerous Symptoms for Infants

Many infants with whooping cough do not cough, instead, they have life-threatening pauses in breathing, called apnea. Apnea can cause the infant to turn blue (cyanosis), or they may struggle to breathe. Same infants may have cold-like symptoms for the entire illness.³

Risk Factors

Age and underlying medical conditions are the greatest risk factors for severe illness.¹ People at greatest risk for severe illness include²:

• Infants younger than 1 year old are at the greatest risk for becoming infected and having severe complications. For this reason, pregnant parents in their third trimester of pregnancy may be a source of pertussis for newborn infants and are considered high-risk contacts.⁵
• People with pre-existing medical conditions that may be made worse by whooping cough, such as immunocompromising conditions and moderate-to-severe medically treated asthma, are at high risk for severe infection.

Complications

Pertussis can cause serious and sometimes life-threatening complications in infants and young children, especially those who are not fully vaccinated.³

Diagnosis

Due to its similarity to other respiratory illnesses, whooping cough can be difficult to diagnose.¹ Health care providers diagnose whooping cough by taking a history of signs and symptoms and conducting a physical exam and performing a¹:

• Laboratory test of a mucus sample from the back of the throat
• Blood test (this is a less reliable test for pertussis)

Treatment

Catching whooping cough early, before coughing fits begin, is important⁶ People who are sick with whooping cough can be treated with antibiotics, but it’s important to start treatment before three weeks of illness. After three weeks, antibiotics are less likely to help. This is because the infection-causing bacteria are gone, but the airways have been damaged and will take time to heal—and symptoms from that damage may still be present.

If symptoms become more severe, treatment in a hospital may be necessary. Hospital treatment usually focuses on⁶

• Keeping the airways clear
• Monitoring breathing and giving oxygen as needed
• Preventing dehydration, either through drinks or providing intravenous fluids (through a vein)

Managing Care at Home

Most people can take care of their symptoms at home by doing the following⁶:

• Take antibiotics as prescribed. The typical treatment for pertussis is a five-day regimen of antibiotics. A person is no longer contagious once this treatment has been completed.
• Keep your home free of things, like smoke, dust and chemical fumes, that could irritate your airways and cause coughing.
• Use a humidifier to help with mucus and coughing.
• Drink plenty of fluids.

Do not take cough medicine unless your medical provider recommends it.⁶ Cough medicine isn’t likely to help and isn’t recommended for children younger than 4.

Prevention

Pertussis is preventable—and severe illness can be prevented by being vaccinated for pertussis and by completing a course of antibiotics if you are infected with pertussis or exposed to someone with pertussis.¹

In 2019 and 2020, there were 178 and 90 cases of whooping cough reported in Spokane County, respectively. Case rates for those years were above Spokane County’s five-year average. See the communicable disease dashboard to see county, state and national rates.

See the Dashboard

Take steps to prevent the spread of pertussis just as you would for other respiratory illnesses like flu or COVID-19. Prevention measures like getting vaccinated, completing treatment if positive, receiving PEP in case of exposure, and practicing good respiratory illness hygiene are effective at preventing the spread of pertussis.

Practice Good Respiratory Illness Hygiene

Practicing good respiratory hygiene is always recommended to prevent the spread of respiratory illnesses, including pertussis^1,11:

• Stay home while sick and away from others if you have symptoms.¹² If you are prescribed antibiotics as part of your treatment, you will no longer be contagious after five days of treatment and can be around others again on day six (6), after five days of appropriate treatment.¹³
• Practice good hygiene by covering coughs and sneezes with a tissue (cough into your elbow if you do not have a tissue) and washing your hands properly.¹¹
• Clean frequently touched surfaces, such as counters and doorknobs.¹¹
• Take steps for cleaner air by opening doors and windows or using exhaust fans.¹¹
• Seek health care right away if you have risk factors for severe illness.¹⁴

If You Have Been Exposed to Pertussis

If you have been exposed to pertussis, contact your doctor to find out what steps to take. They may recommend that you receive PEP (antibiotics) to help prevent you from becoming sick.