Adult pertussis lacks whoop in cough

DEAR DR. ROACH » I have an adult son with serious medical issues. Because of a persistent cough, he saw his internist four times, as well as a pulmonologist. Blood tests and Xrays were negative. His diagnoses over time included: a bad cold, allergies and sleep apnea. During those months, he was prescribed several antibiotics and steroids, as well as other medications.

Soon I, too, began having cold symptoms — running nose, sneezing, coughing, exhaustion — then increased choking from mucus. I tried natural treatments, to no avail. One night my cough changed in both sound and severity. My throat was slightly sore and my glands a bit swollen: I knew the diagnosis.

In the morning, I went to the doctor and said, “I have adult whooping cough.” He agreed. I was put on doxycycline for four weeks. My son is finally on a similar medication. Loss of time, job income, fear of suffocation — all so terrible to experience.

How long is this contagious? When we are better, should we take a booster shot for pertussis (whooping cough)? Do people realize how dangerous this is for babies? I’ve been told their pertussis vaccine is only 70 percent effective. How long are vaccinations and booster shots effective? Please fully explain whooping cough in adults. I believe it’s being misdiagnosed much too often! Thank you. — L.S., R.N. DEAR READER » Whooping cough is caused by the bacterium Bordatella pertussis and is a very contagious illness. In adults, it causes nonspecific symptoms, including cough, which can be severe (the “whoop” inspiration that makes this condition recognizable in children usually is absent in adults). I’d agree with you that this infection is frequently not diagnosed.

The infection typically begins seven to 10 days after exposure (colds and the flu have much shorter incubation periods). The first phase (called the catarrhal phase) lasts one to two weeks and seems like a cold: feeling unwell, runny nose, mild cough. Eye redness and tearing are common, but it is seldom recognized as pertussis.

The second phase is the paroxysmal phase, and is characterized by severe cough. The cough is forceful, has several spasms in a single exhalation, and can lead to vomiting, fainting or loss of urine. This phase lasts up to three months.

The convalescent phase lasts a week or two, during which symptoms gradually decrease. People are most infectious in the catarrhal phase and the first two weeks of the paroxysmal phase. This is the time when antibiotics also are most likely to be effective. However, antibiotics still may reduce infectivity to others, so health care workers and people working with small children should be treated as soon as the condition is suspected. Azithromycin is the usual treatment.

Neither natural infection nor vaccination leads to lifelong immunity. It is hard to make the diagnosis; obtaining a correct specimen is hard, and many physicians fail to consider the diagnosis. It’s important to know whether there is an outbreak in the area; many public health departments send that information by email. Adults should have a booster vaccine, the TDaP, and pregnant women should have a booster with each pregnancy. More information is available from the Centers for Disease Control and Prevention website at https://tinyurl.com/ cdcpertussis vaccine.