About 4,000 new cases of whooping cough (pertussis) occur in the United States each year. That’s significantly less than the 183,000 cases reported to the Centers for Disease Control and Prevention in 1940 before the wide availability of the pertussis vaccine. Whooping cough is caused by Bordetella pertussis bacteria, which affect the linings of the airways, causing swelling and narrowing of the breathing passages. It is suspected that whooping cough is more common than we think, especially in teenagers, so vaccination remains important.
Signs and Symptoms
A severe, violent, and rapid cough is the most common symptom of whooping cough. The respiratory secretions that are expelled during these coughing episodes can spread the disease to other people. When a child develops whooping cough, he has bursts of coughing that result in shortness of breath. After a coughing spell, he breathes in deeply. This breathing pattern often makes a whooping sound as the child breathes in, only to be followed by the next coughing spell.
Before a child develops the characteristic cough of pertussis, his illness will begin with symptoms that might be mistaken for the common cold (eg, runny nose, nasal congestion, sneezing, low-grade fever). As the cough and the whooping sound develop and worsen, his lips and fingertips may take on a dark or bluish color because of a lack of oxygen during the coughing spells. Other symptoms may include
These children also become more vulnerable to other infections, including pneumonia, as well as complications such as seizures. For children younger than 1 year, whooping cough leads to pneumonia about 20% of the time. In general, the disease is most severe in babies in the first 6 months of life, particularly in those who were born prematurely (preterm). In all ages, the cough lasts for months—this illness has been called the 100-day cough.
Once a child has been infected with pertussis bacteria, symptoms may occur 7 to 10 days later, although this incubation period can last from 6 to 21 days.
When to Call Your Pediatrician
Contact your doctor if cold-like symptoms are followed by symptoms that could indicate the presence of whooping cough. These include a cough that worsens, becoming much more violent and frequent, and a darkening of the fingertips and lips during the cough. Your child may vomit at the end of a coughing spasm. He may also be extremely tired from the severe coughing and may have difficulty eating and drinking.