Ask Dr. Dunn: whooping cough (pertussis)

By Maren Dunn, D.O. ExploreBigSky.com Health Writer

Is whooping cough going around the community?

– Eric, Big Sky

Cold symptoms run rampant in the wintertime, and this year has been no exception – especially when it comes to the contagious cough running around Big Sky.

Since 2004, there has been a frightening resurgence of pertussis, or whooping cough in the U.S., and 2010 tallied the most cases in more than 50 years, with 27,550 nationwide. We’re still experiencing what the Centers for Disease Control has called “the worst whooping cough epidemic in 50 years,” though case numbers are dropping due to increased vaccination rates.

Whooping cough is a highly contagious upper respiratory illness caused by Bordetella pertussis. In the pre-vaccine era, children under 10 predominantly contracted the illness, stricken with prolonged cough and one or more of the classic symptoms: a “whoop” noise between coughs, severe coughing fits, and cough followed by vomiting.

It can be hard to know if a community is experiencing a pertussis outbreak, because affected individuals tend not to seek treatment during the first stage – confirmation of the illness, done through lab testing, is only reliable during the first 2-4 weeks. This is also the time period when medicine can actually shorten the course of the illness. Unfortunately, most cases go undetected.

If treated after two weeks, antibiotics may not shorten the illness but are likely to decrease the spread of the bacteria. Most infected individuals clear the illness within 3-4 weeks without treatment.
Since the 1990s, pertussis has affected mostly adolescents and adults, due largely to waning immunity. While their symptoms can be less severe than in children, these age groups can carry the illness to children and infants who are at higher risk of severe illness and death. Once infected, the typical incubation period is 7-10 days. This is much longer than the common cold, where incubation takes about three days.

Infections have three phases of illness. In the first stage, which lasts 1-2 weeks, runny nose, malaise and mild cough are common; high fever is atypical. Other early symptoms include excessive eye watering or redness.

The hallmark symptom occurs during the second stage, which starts around week two: severe, forceful coughs during exhalation, followed by a vigorous inhalation that sounds like a “whoop.” Often a person will have paroxysms, or fits of these distinctive coughs.

Since their airways are smaller, the whooping noise is more pronounced in young children, who may also stop breathing between coughing spells. This can be alarming, since the paroxysms can cause a person to vomit or pass out. In adolescents and adults, this period can last 2-3 months. Finally, within two more weeks, the symptoms subside.

If the illness is recognized, antibiotics are prescribed. However, neither natural infection nor vaccination offers life-long immunity, so following vaccination schedules is critical. The childhood vaccine is called DTaP (diphtheria, tetanus and acellular pertussis) and is given at 2, 4, 6 and 18 months of age, and at 4 and 11 years of age. An infant less than 2 months old is at high risk of pertussis infection and death.

To help protect this population, doctors recommend all pregnant women have a booster during their third trimester and repeat vaccination for every pregnancy. A pregnant mother passes on antibodies to the unborn child, offering protection until the child receives the first vaccine.

Since immunity wanes years after vaccination, it’s necessary for adults to get boosters, as well. The adult vaccine is called Tdap (tetanus, diphtheria and acellular pertussis). Tdap is now routinely given at least once after age 18. If you are unsure if your recent tetanus booster was a Tdap, get the Tdap vaccination immediately. This will help maintain immunity and reduce the possibility of passing the illness to a child.

See your medical provider if you suffer from a cough for longer than a week or show typical symptoms of whooping cough. If you’ll be spending time with a new baby, help protect it from pertussis by getting your vaccine.

Find Dr. Dunn’s writing regularly in the Health section of the Big Sky Weekly.

Maren Dunn, D.O., is owner of Gallatin Family Medicine, a medical clinic in the Big Sky Meadow Village. Gallatin Family Medical offers reduced cost and free mammogram screening. Have a question? Email her at inquiries@gallatinfamilymedicine.com.

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