What do we all need to know about whooping cough (pertussis)? WebMD asked epidemiologist Tom Clark, MD, MPH, of the CDC's National Center for Immunization and Respiratory Diseases.
What is whooping cough?
Whooping cough is a bacterial infection that's highly contagious, and it's also vaccine preventable. Especially in young kids and unvaccinated people, it causes a severe cough, which is the reason for the name, "whooping cough."
What kind of infection causes whooping cough?
It's caused by bacteria called Bordetella pertussis.
What are the symptoms of whooping cough?
It starts like a cold, with congestion and upper respiratory symptoms, and then progresses to a cough. You have fits of coughing that are so severe that you can't stop or catch your breath.
It's that severe, prolonged cough, and especially the characteristic paroxysms [uncontrolled fits] of cough that trigger physicians to be worried about pertussis and try to confirm the diagnosis.
The symptoms are pretty nonspecific, and so doctors don't always suspect it. Pertussis is high on the list if that whoop is present. The “whoop” sounds like a sharp gasping intake of breath after all the air has been coughed out of your lungs. If it's not, it's likely to go unrecognized because there aren't really other signs and symptoms that are as characteristic.
How does whooping cough spread from person to person?
It spreads through close contact with oral secretions or respiratory droplets. So it's easily spread through the cough, especially when people are in close contact, like living in the same house with a person who has whooping cough. It can also be spread through sneezes - anything that spreads respiratory secretions.
Who is most at risk for whooping cough?
The highest incidence is in infants, and they're also at greatest risk for complications if they develop the disease. In fact, the great majority of fatal cases in the country each year are in infants less than 6 months of age, especially if they're too young to have received their first vaccination.
How is whooping cough treated?
It's a bacterial infection, so it can be treated with antibiotics, usually erythromycin or a family of antibiotics like erythromycin. Erythromycin is taken for 2 weeks.
If antibiotics are recommended, they should take all the doses and finish the recommended course. It's important for a couple of reasons. If the child's doctor feels that antibiotics are necessary, it's important to take the doses on time to develop and maintain the appropriate antibiotic levels in the blood to clear the infection. And missing a dose or stopping early can sometimes result in a relapse. It's also important in general, because one of the things that promotes antibiotic resistance in bacteria is stopping and starting [antibiotics].
Over-the-counter cough medicines are not recommended and don't really help. The prescription medicines that are really effective for cough are pretty strong medicines, so they're generally avoided in young children and probably not effective in pertussis specifically.
It's commonly recommended to minimize the things that can trigger the cough. A humidifier helps. Breathing moist air will help. With younger kids, try to keep them calm and not agitated or running around.
Infants or people with severe disease sometimes require ... hospitalization, sometimes in intensive care. It can be serious enough to require intubation and ventilation -- in which a breathing tube is inserted into the throat, both to protect the airways and to assist with breathing until they can recover from the infection.
What health problems can whooping cough cause in infants?
Concerning things include pneumonias. Because the cough is so severe, blood vessels can break because of the pressure generated from coughing. That causes bleeding inside the brain, which can be very serious. In infants [whooping cough] can be life threatening.
How can I prevent my baby from getting whooping cough?
Whooping cough is commonly thought of as sort of an old-time disease of childhood that went away with vaccination, but it never really went away. So it's important that we maintain high vaccination coverage in kids. It's also a disease that adolescents and adults can get.
The best way to prevent it is to get vaccinated. For kids, vaccinations start at 2 months. They get the pertussis vaccination with diphtheria and tetanus. And then doses at 4 months and 6 months. Then there's a booster at 15 to 18 months, and another booster at 4 to 6 years before they start school.
The Tdap vaccine is recommended for all adolescents, preferably at age 11 or 12 during a preventive care visit with their doctor. But anyone who hasn't gotten it at age 11 or 12 can get a dose.
If adults have never had [the vaccine], they should definitely get it, and they can get it at any time. They don't have to wait until they're due for their tetanus vaccine.
For infants who are too young to be vaccinated and who are at highest risk for disease and severe complications, we recommend that everybody who is in the house or caring for the baby get vaccinated to help protect the baby.
How do outbreaks of whooping cough start?
Things that can promote outbreaks or promote the spread of disease include low vaccination coverage. Protection from the vaccine doesn't last forever. Immunity wanes over time. That's why you commonly see outbreaks in teenagers.
The reason that the adolescent and adult Tdap booster was developed was really the increase in disease observed in teenagers and young adults as a result of waning immunity.
Are we seeing more outbreaks of whooping cough, and if so, why?
It definitely comes and goes. There are frequently outbreaks. But most are kind of small clusters of dozens of cases. Large, community-wide outbreaks are pretty rare. Occasionally, every 3 to 5 years, we see big increases in states or regions of the country.
Transmission is a definite and recognized cycle. It's thought that as transmission declines, the number of people in the total population who are susceptible gradually increases because the disease isn't circulating as much, and protection from the vaccine wanes over time. And then transmission gradually increases and runs through the susceptible population until it starts to decline again.
Do other family members need to take preventive antibiotics or vaccine boosters if they've been exposed?
They do. It's always important to make sure that kids are up-to-date with their immunizations. With the Tdap booster, make sure adolescents and adults are up-to-date with their immunizations. The person with pertussis should be treated, and people who are in close contact should get preventive antibiotics.