It's Not Just in the History Books!
So, what do we need to know about pertussis? It is caused by a bacterium, Bordetella pertussis, and it is spread person-to-person by coughing. Most of us are vaccinated against it as children with our “baby shots,” but immunity fades within a few years of our last immunization, and this has a lot to do with its current rising incidence. While there were just 7000 cases reported in the U.S. in 2001, in 2004 there were 19,000 cases.
Pertussis is very contagious – as many as 80-90% of household members will get the disease if someone at home brings it in. The incubation period is about a week. Then the cough starts (along with other mild symptoms that suggest a “cold”). The cough is mild at first (and this is when folks are most contagious), but gradually gets more severe until it reaches the paroxysmal stage which is characterized by fits of coughing, often ending with vomiting and the classic “whoop.” Unfortunately, the cough often lasts about 10 weeks, even with treatment – thus, the term “hundred day cough” used to describe pertussis. Even the convalescent stage is prolonged, as it can take weeks to months for the cough to completely go away.
Small children (under about 6 months) are at risk of apnea (or cessation of breathing), pneumonia and death. The disease is rarely fatal to older children or adults, but weeks to months of severe coughing is nothing “to sneeze at.” Many older kids and adults have less severe courses, which is good for them, but they may be unknowingly spreading the disease into the community.
The health departments in our states keep a close watch out for this disease, and, when it is discovered in the community, physicians report it to the authorities so that warnings can be sent out. We generally suspect the disease in people who have had coughs for more than a couple of weeks. We have tests for the disease, though they’re less than perfect. If the disease is picked up, the recommendation is to begin antibiotic “prophylaxis” (generally with 5 days of antibiotics such as azithromycin) to all close-contacts (at home, the work place, school, etc.) in order to try to prevent its spread. Antibiotic treatment of those who have actually contracted pertussis helps to limit spread, but doesn’t do much to shorten the course of the illness.
For more information, check out the CDC web site at: http://www.cdc.gov/doc.do/id/0900f3ec80228696
That little 2 month old girl I saw in the ER yesterday sure was cute, but I have a colleague who contracted pertussis last year from a patient in our Peds ER. It was not a pretty thing. And, one of our nurses was telling me last night how she broke a couple ribs from her pertussis cough a few years ago. I think I’ll go take my antibiotic now…
Stay alert and stay safe.
- Dr. Bob