Pertussis (Whooping Cough)
Pertussis, commonly known as whooping cough, is a highly contagious bacterial respiratory infection that causes severe, prolonged coughing fits. It is especially dangerous for infants under 12 months who are not yet fully vaccinated. The illness progresses through stages and can last 6–10 weeks or longer, earning it the nickname "the 100-day cough."
Common symptoms
- Cough
- Runny Nose
- Fever
- Fatigue
- Vomiting
Cause
Pertussis is caused by the bacterium Bordetella pertussis. It spreads very easily through respiratory droplets when an infected person coughs, sneezes, or shares breathing space. An infected person can spread it from the onset of symptoms through at least 2 weeks of coughing, or until 5 days of appropriate antibiotic treatment.
How common is it?
Pertussis remains a significant public health concern with periodic outbreaks occurring every 3–5 years in the U.S. The CDC reports thousands of cases annually, with the highest rates in infants under 1 year. Outbreaks are common in schools and childcare settings, particularly when vaccination rates decline.
Treatment
Pertussis is treated with antibiotics, typically azithromycin, clarithromycin, or trimethoprim-sulfamethoxazole. Early treatment (within the first 1–2 weeks) can reduce severity and prevent spread. Supportive care includes small frequent meals to reduce vomiting after coughing fits, plenty of fluids to prevent dehydration, rest in a calm and quiet environment, and using a cool-mist humidifier. Infants under 1 year, especially those under 6 months, may require hospitalization for monitoring, suctioning, and oxygen support. Seek emergency care for any pauses in breathing (apnea), blue or purple skin color, inability to keep fluids down, or signs of dehydration.
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The free kit checklist that covers Pertussis (Whooping Cough) and the other bugs going around, so you are stocked before it hits your house.
Open the cold and flu season kitPrevention
Vaccination is the most effective prevention. The DTaP vaccine is given to children at 2, 4, 6, and 15–18 months, with a booster at 4–6 years. The Tdap booster is recommended for preteens at age 11–12 and for pregnant women during each pregnancy (to protect newborns). Additional prevention measures include keeping infants away from anyone with a persistent cough, ensuring all caregivers and close contacts are up to date on pertussis vaccination (cocooning strategy), and practicing good hand hygiene and respiratory etiquette.
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Frequently asked questions
Pertussis (Whooping Cough) articles for parents
- October 2025When Should Kids Stay Home from School?Guidelines to help parents make the tough call about keeping sick kids home.
- December 2025Managing School Sick Days: A Chicago Working Parent's Survival GuideWhen your child is sick and you have work, something has to give. Practical strategies for Chicago parents juggling careers and caregiving.
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Medical disclaimer: Educational only. Always consult a healthcare provider for diagnosis and treatment.