A cough that began like a mild cold but is still going after two or three weeks, especially one that ends with a gasping breath, is a reason to think about whooping cough. Pertussis can be especially dangerous for young infants.

Why It Happens and How It Spreads

Pertussis is caused by the bacterium Bordetella pertussis and spreads through droplets from coughing and sneezing. Protection from vaccines tends to fade over time, so older children, teens and adults can carry the infection with mild symptoms and pass it to babies who are too young to be fully vaccinated.

How It Looks at Different Ages

CDC describes an early stage that resembles a cold: runny or stuffy nose, a low-grade fever under 100.4°F, and a mild occasional cough. After one to two weeks, coughing fits tend to become more severe and may last for weeks, sometimes followed by vomiting or a high-pitched “whoop” as the child inhales. Older children and adults may have only a lingering cough. Infants often look different: many do not cough at all, and instead may have apnea (pauses in breathing), turn blue, or feed poorly. CDC reports that about 1 in 3 babies younger than 1 year who get whooping cough needs hospital care, and the younger the baby, the higher the risk.

Care and Prevention

If pertussis is suspected, a pediatrician can test and, if appropriate, start an antibiotic, which is most helpful early in the illness. Keep a coughing child away from infants and ask the doctor when it is safe to return to school or child care. At home, small frequent feedings, fluids and a humidifier may ease discomfort. Vaccination is the main protection: CDC recommends DTaP at 2, 4 and 6 months, 15-18 months and 4-6 years, with a Tdap booster at age 11-12. CDC also recommends a dose of Tdap during every pregnancy, ideally early in the third trimester (27-36 weeks), so that antibodies pass to the newborn.

Common Misunderstandings

  • Pertussis is not just a disease of the past; it still occurs.
  • Being vaccinated does not guarantee a child will never catch it, but vaccination tends to make illness milder.
  • No whooping sound does not rule it out, and infants often have none.
  • Over-the-counter cough medicines are not a substitute for an evaluation.

When to Seek Care

Book a visit if a cough lasts more than two weeks or comes in violent fits. Go to the emergency room right away if an infant has pauses in breathing, turns blue or gray around the lips or face, cannot feed because of coughing and vomiting, or becomes limp or hard to wake. Fast, labored breathing in any child is also a reason for urgent care. This information is based on U.S. (CDC) guidance; if you live elsewhere, check with a local pediatrician for country-specific recommendations. This information isn’t a diagnostic tool and doesn’t replace advice from a medical professional.