The Cough That Won't Go Away

Pertussis, or whooping cough, can drag on for weeks -- even months -- before it's detected and is notoriously hard to treat.

woman holding child Alexandra Grablewski

When Avery Holdsworth was 3 months old, she began coughing so hard that "she would almost lift her little body off the crib mattress," remembers her mother, Amanda Holdsworth, of Howell, Michigan.

When she wasn't coughing, which was most of the time, Avery looked fine. And she didn't have a runny nose or a fever. However, the cough was so severe that Holdsworth took her daughter to the pediatrician three times in ten days. The doctor ruled out RSV (respiratory syncytial virus) and allergies, but the cough continued. Finally, Holdsworth's husband suggested having Avery tested for pertussis because a client's child had recently been diagnosed with it.

"I said, 'Whooping cough? Isn't that like a Little House on the Prairie disease?'" recalls Holdsworth. She was shocked when Avery tested positive.

Once upon a time, whooping cough (or pertussis) was as dreaded a disease as polio, says Parents advisor Harley Rotbart, M.D., professor of pediatric infectious diseases at the University of Colorado School of Medicine and Children's Hospital of Colorado in Aurora. "It was a quite severe, life-threatening bacterial illness that took young babies from parents."

But we've grown up in the era of pertussis vaccination. The DTaP vaccine (which combines diphtheria, tetanus, and pertussis) is given to children at 2 months, 4 months, and 6 months, and again between 15 and 18 months and 4 to 6 years of age. Most parents have never seen or heard whooping cough because widespread immunization campaigns dramatically reduced the rate of the disease. After the vaccine was introduced in the 1940s, cases declined by more than 99 percent. By 1976, there were only about 1,000 cases nationwide.

Unfortunately, it's a drastically different situation today. Pertussis is on the upswing, thanks to what some experts call a perfect storm of innocent ignorance, anti-vaccine sentiment, and less-than-perfect immunizations. In 2012, more than 41,000 confirmed cases of whooping cough were reported to the Centers for Disease Control and Prevention (CDC) -- the most since 1955. "That's likely just the tip of the iceberg," says Mary Anne Jackson, M.D., section chief of infectious disease at Children's Mercy Hospital, in Kansas City, Missouri. "Many cases go undiagnosed and many don't get treated with antibiotics, so the disease continues to spread." Babies are at highest risk of getting pertussis and becoming dangerously ill, but more school-age children are getting sick than ever before too.

One of the biggest dangers of the disease is that it is often not diagnosed until it has progressed to a more serious stage, when breathing becomes difficult. At that point it's easy to develop respiratory infections like pneumonia. "Children can literally suffocate because they cannot catch their breath. Their cough and whoop can be so severe that they die of oxygen deprivation," Dr. Rotbart explains. Understanding the facts about the disease known as "the 100-day cough" will go a long way to helping prevent it.

    Vaccine Surprises

    The earliest pertussis vaccines, called "whole-cell," were made from the entire pertussis bacterium and were nearly 95 percent effective. However, the public worried that they may have sometimes caused serious nervous-system side effects, such as seizures. Though studies never proved that, scientists created a safer "acellular" vaccine that uses only part of the bacterium. This is the shot American kids have gotten since 1990.

    But after a startling number of vaccinated preteens in California came down with whooping cough in 2004, researchers investigated and learned that the current vaccine can be as low as 70 percent effective, Dr. Jackson says. Doctors also suspect that the immunity the vaccine does confer may wear off over time. A study published last year found exactly that: Immunity wanes after the fifth dose, traditionally given before kids enter kindergarten, which explains why so many kids ages 7 to 10 are coming down with pertussis. In fact, children who have not received all five of the recommended DTaP shots are eight times more likely to get whooping cough than those who are fully immunized, reports the CDC. Since 2005, it's been recommended that kids receive a booster shot called Tdap (tetanus, diphtheria, and pertussis) at age 11 or 12. Kids 7 to 10 who haven't gotten all five doses of DTap should also receive a single dose of Tdap. Some experts believe every 7- to 10-year-old should get Tdap, but that hasn't been officially recommended yet.

    Only about 70 to 85 percent of teens and roughly 13 percent of all adults are fully immunized against pertussis, says the CDC. If vaccinated kids do get sick, they may still cough for an extended time but generally won't be as ill as kids who haven't gotten the booster.

      What Does Whooping Cough Sound Like?

        Vulnerable Babies

        Even though more older kids are getting whooping cough now, it is babies who are still at highest risk. At least 18 babies died of whooping cough in 2012 (2013 stats weren't available at press time). Infants are relatively unprotected against pertussis until a few weeks after they've received their third dose of DTaP, which is typically given at 6 months of age. They're the most likely to be admitted to the hospital with whooping cough and to develop serious complications.

        To protect a young baby, experts recommend a "cocooning" strategy. This means parents should get the Tdap booster and all siblings should be vaccinated, as should anyone who will be around the baby -- child-care providers, aunts, uncles, friends, grandparents. (Unsure if you've had Tdap -- or DTaP? Check with your doc. Many adults mistakenly assume they're protected.)

        The CDC's Advisory Committee for Immunization Practices says that expectant moms should receive a Tdap vaccination during each pregnancy in order to protect their baby, even if they've gotten Tdap before. "We want to make sure all pregnant women are vaccinated, preferably between 27 and 36 weeks," says Laurie Swaim, M.D., an ob-gyn at Texas Children's Pavilion for Women, in Houston. This way a mom passes immunity on to her baby, which offers some protection until he starts getting his own vaccines at 2 months.

        Spotting the Disease

        At first, whooping cough looks a lot like a cold: Symptoms include a runny nose, a mild cough, low-grade fever, sneezing, and loss of appetite. That's why it's hard to catch it early. The second stage of the illness, which occurs about two weeks after the onset of symptoms, is when the cough gets worse. "A young baby may cough to the point where he chokes or turns blue. Older kids and adults might cough so hard that they pass out or vomit," Dr. Jackson says. It's typical for a child to cough ten to 20 times in a row before stopping to take a breath. When he quickly draws air into his lungs, that can cause the telltale whooping sound. This stage can last for up to ten weeks. The third stage, which is when kids are particularly susceptible to secondary respiratory infections like pneumonia, lasts for another two to three weeks.

        But not everyone who has whooping cough whoops. Talk to your doctor if your child has been having coughing fits for a period of longer than two weeks or coughs to the point of vomiting.

          How It's Treated

          Whooping cough is definitively diagnosed via a nasal swab, which is similar to a strep-throat test. The swab has to be sent to a lab for diagnosis, though, and not all doctor's offices are equipped to perform, store, and ship pertussis tests for analysis. So some doctors will check your child's white-blood-cell count with a blood test; the ratio of certain types of white blood cells can indicate a whooping-cough infection. However, this doesn't always pick up the disease.

          Because whooping cough is so contagious, your doctor may start your child (and everyone else in your home) on antibiotics before any test results are back. They won't stop the cough, but they may help shorten or lessen the disease if it's picked up within the first seven days after infection, Dr. Jackson says. (But most people don't know they have whooping cough until coughing spasms begin two or three weeks after infection.) Untreated, your child can spread pertussis for three full weeks after the cough begins. If the test results come back negative, you can stop the meds. But if your child does indeed have pertussis, you'll have helped halt the spread.

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