Summary
Highlights
Whooping cough, also known as Pertussis, is a severe lung infection caused by the bacteria Bordetella pertussis. It is characterized by violent, uncontrollable coughing fits and a distinctive 'whooping' sound during gasping breaths. The CDC estimates 24 million cases worldwide annually, with 160,000 deaths. It's particularly dangerous for babies under one year old due to their small airways.
Whooping cough has been recognized since the Middle Ages. The causative agent, Bordetella pertussis, was identified in 1900. This bacteria is a small, strictly aerobic, gram-negative coccobacillus. It spreads person-to-person through respiratory droplets and attaches to the cilia in the upper respiratory tract. It produces four toxins (pertussis toxin, adenylate cyclase or hemolysin, dermonecrotic toxin, and tracheal cytotoxin) and two lipopolysaccharides, which together cause tissue damage, inflammation, and an immune system overreaction.
After a 7-10 day incubation period, symptoms begin. The initial stage presents as cold-like symptoms (runny nose, mild cough, low-grade fever), which is when the bacteria count is highest and transmission risk is greatest. After a week or two, the disease progresses to violent, rapid coughing fits, leading to lung air depletion and the characteristic 'whooping' sound upon inhalation. Extreme coughing can cause vomiting, exhaustion, weight loss, loss of bladder control, fainting, or rib fractures. The disease can last up to 10 weeks or more, earning it the nickname 'the hundred day cough'.
Bordetella pertussis only infects humans. Diagnosis involves physical examination, mucus lab tests, or blood tests. Antibiotics are effective if administered early (within three weeks of illness onset) to reduce coughing and transmission, but do not reverse existing damage. Vaccination is crucial for protection. The DTaP vaccine is recommended for babies and children, and the Tdap booster for teens and adults, particularly those visiting newborns. Covering coughs and sneezes and handwashing also help prevent spread. Despite its long history, whooping cough remains a common disease and a leading cause of vaccine-preventable deaths globally.