Pertussis cases on the rise; CDC recommends booster

The immunization wears off over the years.
RALEIGH NEWS & amp; OBSERVER
When Debbie Quinn's newborn son developed a runny nose and a cough within weeks of his birth in June, Quinn figured he had picked up her husband's lingering cold.
But little Austin's symptoms quickly grew severe, until he had violent coughing spells that shook his body and turned him beet-red. He began to vomit after taking a bottle. Alarmed, Quinn and her husband, Buddie, who live in Raleigh, took their 1-month-old son to the emergency room.
The ER doctor at WakeMed listened to the infant's cough and almost instantly said a word the Quinns had never heard before: pertussis.
It scarcely helped when the doctor went on to explain that pertussis is another name for whooping cough. Debbie Quinn's first thought was that it was an old disease that modern medicine had knocked out decades ago.
"I probably gave [the doctor] the weirdest look possible," Quinn said. "I said, 'I thought we had shots for that. I thought we were immune.'"
Despite widespread vaccination for whooping cough -- about 86 percent of children nationally receive the immunizations to protect against the disease, according to the National Center for Health Statistics -- the old foe is on the rise. During the 1930s and 1940s, whooping cough sickened an average of 200,000 people a year and killed about 4,000 annually. It presents an especially deadly risk for infants, attacking their fragile lungs and causing serious breathing problems.
Background
After immunizations were introduced in the 1940s, the number of whooping cough cases nationally fell to a low of about 1,000 a year in 1976. But the U.S. Centers for Disease Control and Prevention has observed a 25-fold increase in reported cases of the disease since then. Whooping cough is the only vaccine-preventable disease that is increasing in the U.S.
Medical experts think the increase is due to waning immunity in adolescents and adults, whose childhood shots for whooping cough essentially wear off over time. Children typically receive their final vaccination for whooping cough, part of a combination shot known as DTaP, by the time they reach age 6. This year, to address the problem, the CDC began recommending an additional booster shot for children 11 and older and for adults up to age 64.
Waning immunity would be no cause for concern if whooping cough weren't still circulating in the community, said Dr. Jeffrey Engel, North Carolina's state epidemiologist. He said outbreaks can often be traced to groups or individuals that haven't been immunized for medical or religious reasons.
Last year, more than 25,000 cases of whooping cough were reported nationally.
Physicians and public health experts say they think reported cases represent only a small fraction of actual cases. In adults and older children, the symptoms resemble those of the common cold. As a result, the true diagnosis is often not recognized. Symptoms may not become severe in older patients, and many never develop the signature "whoop" that often accompanies coughing spells in patients with serious cases.
"A lot of people will try to tough it out at home," said Dr. Tom Belhorn, a pediatric infectious disease specialist at UNC Hospitals. "But if you have a persistent cough that lasts for a couple of weeks, you need to be seen by a physician."
Infected patients can remain contagious for up to three weeks after contracting whooping cough. If they happen to come in contact with an infant or person with respiratory problems, the consequences can be serious.