Whooping cough can be misdiagnosed as cold

My best friend’s daughter spent two weeks abroad in between her college semesters. She had a fabulous time, and landed back in her dorm room the day before school started, not quite ready to roll. She didn’t feel so great. The cold she got overseas got worse and she couldn’t stop coughing. She was running a high fever, up to 105. That’s when her mom called me.

“Can you talk to her? She won’t go to the doctor!” So Auntie Stacie got on the phone. Together we convinced her that colds don’t usually give you a temperature that high, and since she’d been overseas, she might have brought something weird back.

Well, she finally felt so bad she went. “She’s got whooping cough!” my friend called to tell me. Now, I know this family and they got all their vaccinations, so how did that happen?

I asked Dr. Heather Armstrong, faculty at Family Medicine Spokane, what was going on.

“We probably under-diagnose whooping cough in adolescents and adults,” she said. “The vaccine doesn’t give immunity forever. It probably wears off after 10 years.” Whooping cough is highly contagious, and adolescents and adults are now the reservoir for the disease.

Whooping cough, or pertussis, is the most common vaccine-preventable disease diagnosed in children under age five. In very young infants, it can cause a severe illness, leading to pneumonia and even death. That’s what mothers experienced in the early 20th century, before vaccines against pertussis were developed.

In adolescents and adults, almost all cases of whooping cough appear in patients who have been previously vaccinated. That’s one reason it’s under-diagnosed in this age group. We figure since the patient was vaccinated as a child it’s not whooping cough. But as Dr. Armstrong pointed out, the vaccine-promoted immunity does not last forever. At this point, re-vaccination is not recommended for the older age group.

Pertussis can easily be misdiagnosed as a bad upper respiratory infection – otherwise known as the common cold – starting off with symptoms of a runny nose, weepy eyes, sneezing, low grade fever (Emmy obviously didn’t read that part of the book) and a mild cough. The mild cough soon turns wicked; patients have severe spasms of numerous, rapid coughs, followed by a quick inspiration of air. Sometimes this breath will sound like crowing or like a “whoop.” Hence the name. This trademark trait got Emmy her diagnosis, although most often in teens and adults, the classic sound is missing, further contributing to diagnostic befuddlement. These fits of coughing can do great damage to any attempt to get a good night’s sleep. Just ask Emmy’s roommate – she moved in with a friend to escape the noise.

To make matters even more undignified, vomiting often follows the coughing spells, and this can be a clue for the clinician who is trying to figure out what’s going on. The coughing spells can last for four to eight weeks. In fact, prolonged coughing is another hint to the proper diagnosis.

Unlike the common cold, whooping cough is a bacterial infection, not viral. This is important, because it can, and should, be treated with antibiotics. Pertussis can be contagious for up to four weeks, but antibiotics can reduce that time to five to seven days after the medicine is started. You never know when you’ll run into an unprotected child, and besides, who wants to be sick for that long?

The most vulnerable among us are very young infants, especially if they have yet to receive their childhood vaccinations. In the United States, about 80 percent of deaths from pertussis occur in children under one year of age. So it is important that household contacts, especially adults and very young children, receive antibiotics to prevent infection.

I’m happy to say that Emmy is on the mend. As we used to say when the kids were little, “the antibiotic fairy came to visit.” I wonder if she did any of Em’s homework for her?