Pertussis: What is it, and who is at risk?

Infants and children get sick often, picking up various pathogens in child care, playing in the park or sitting in their classrooms. However, sometimes what may look like a routine common cold can actually be much more serious—and it starts with a “whoop.”

What is pertussis?

Pertussis, which has a number of other names including the 100-day-cough or whooping cough, is a bacterial infection that can be very serious in young children and babies. According to the Centers for Disease Control and Prevention (CDC), approximately half of the babies less than 1 year old who get pertussis need treatment in the hospital.

“We see serious cases in infants younger than 6 months old, and pertussis can be fatal, especially in those younger than 2 months,” said Jesse Parr, FAAP, MD, a pediatrician and assistant professor with the Texas A&M College of Medicine. “Most children will get pertussis from older kids, their parents or grandparents, in whom it could look like just a chronic cough.”

In 2012, 48,277 cases of pertussis were reported in the United States—the highest number since 1955, when 62,786 cases were reported. Still, this number is likely an underestimate, as many more cases go undiagnosed and unreported.

What are the symptoms of pertussis?

The disease typically starts with cold-like symptoms and possibly a mild cough or fever, and babies can have a symptom known apnea—which means they can stop breathing. As the disease progresses over the course of a week, more severe symptoms appear. These include coughing fits, a high-pitched “whoop” sound during fits, vomiting and exhaustion before or during the fits.

“It’s called the 100-day-cough because it can last a long time, and in older children and adults it can just present as a chronic cough,” Parr said. “During the coughing spells, which last between 15 and 30 seconds, kids can become red or blue in the face. These instances are separated by relatively cough-free intervals that gradually increase in time as the disease becomes more prolonged.”

Another classic symptom is the high pitch “whoop” sound, which happens during these coughing fits. “Interspersed in the coughing spells are inspiratory whoops as the children breathe in, thus the name ‘whooping cough’,” Parr added.

Preventing pertussis

Pertussis is a very contagious disease, spread easily from person to person. Antibiotics may shorten the amount of time someone is contagious, but the most effective tool to prevent the disease is to get vaccinated. “The only way to protect children who are too young to be vaccinated is for the majority of the population—at least 92–94 percent in the case of pertussis—to be immunized,” said Carrie L. Byington, MD, dean of the Texas A&M College of Medicine, senior vice president of the Texas A&M University Health Science Center and vice chancellor for health services at The Texas A&M University System. “This is referred to as herd or community immunity, when a critical portion of a population is vaccinated against a contagious disease. Community immunity limits the likelihood of an outbreak.”

“Babies under the age of 2 or 3 months rely on the immunity of the population to not get infected,” Parr said. “I saw a case where an infant was 7 weeks old and caught it from older kids in their community who had not been immunized. The baby was unprotected.”

If you are pregnant, live with or care for an infant, talk to your health care provider or pharmacist about getting the pertussis vaccine, called Tdap (because it protects against tetanus, diphtheria and pertussis), to help protect yourself and your baby. Also work with your provider to make sure your baby begins getting their vaccines as soon as they’re eligible at 2 months old. If you plan to be in contact with an unprotected infant, get vaccinated at least two weeks before seeing the baby to give your body time to build antibodies so you’re not risking the infant.

“Our immunity is not 100 percent without vaccines, and for younger children, their immune systems are growing and developing,” Parr said. “The population, and the youngest children in particular, depend upon the rest of us to do our part in providing herd immunity. This is a preventable disease if everyone who can get immunized does.”