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Whooping Cough

Also known as Pertussis, 100 day cough

Severity: SevereCauses an estimated 24 million cases and over 100,000 infant deaths annually

This article is general health information for the selected condition. It is not a diagnosis and does not replace clinical judgement. If you have questions or need treatment advice, please consult a qualified healthcare professional.

What is whooping cough?

Whooping cough is a highly contagious respiratory infection caused by Bordetella pertussis. It produces prolonged violent coughing fits, sometimes followed by a characteristic whoop on inhaling. It is most dangerous in infants under six months, who may not cough typically and can instead stop breathing. Vaccination in pregnancy protects newborns effectively.

Causes

  • Bordetella pertussis bacteria
  • Spread by respiratory droplets
  • Waning immunity after vaccination or infection
  • Close household contact

Symptoms

  • Initial cold like symptoms with mild cough
  • Progression to severe coughing paroxysms
  • Whooping sound on breathing in, mainly in children
  • Vomiting after coughing fits
  • Exhaustion after coughing
  • Cough persisting for weeks to months
  • Apnoea and poor feeding in young infants

Risk factors

  • Infants too young to be fully vaccinated
  • Incomplete or absent vaccination
  • Pregnancy without maternal vaccination
  • Close contact with an infected person
  • Crowded settings

Diagnosis

  • Clinical suspicion in prolonged paroxysmal cough
  • PCR of nasopharyngeal swab in early disease
  • Serology for later presentation
  • Full blood count sometimes showing marked lymphocytosis
  • Public health notification and contact tracing

Treatment

  • Macrolide antibiotics, most effective when given early
  • Antibiotic prophylaxis for vulnerable close contacts
  • Hospital admission for infants with apnoea or feeding difficulty
  • Supportive care with small frequent feeds
  • Maternal vaccination in pregnancy to protect newborns
  • Routine childhood immunisation and boosters

Self care

  • Complete the antibiotic course to reduce spread
  • Rest and take small frequent fluids and meals
  • Keep the air free of smoke and irritants
  • Sit upright during coughing fits
  • Stay away from infants and pregnant women until treated
  • Expect cough to last weeks despite treatment
  • Avoid cough suppressants, which do not help

When to see a doctor

Book an appointment if:

  • Cough with a whooping sound or vomiting after coughing
  • Cough lasting more than two weeks
  • Contact with a confirmed case, especially in pregnancy
  • Any cough in an infant under six months
  • Coughing fits causing exhaustion
  • Pregnancy, to arrange vaccination

Some symptoms need emergency care rather than an appointment. See the warning signs listed above.

Prevention

  • Vaccination in pregnancy, which protects newborns effectively
  • Routine childhood immunisation and preschool boosters
  • Adolescent and adult boosters where recommended
  • Antibiotic prophylaxis for vulnerable close contacts
  • Keep infants away from anyone with a prolonged cough

Outlook

Whooping cough is prolonged, with coughing fits often lasting six to ten weeks or longer, which is why it is called the hundred day cough. Older children and adults recover fully. Infants under six months are at real risk of pneumonia, seizures and death, which is why maternal vaccination is emphasised so strongly.

Common questions

Why is vaccination in pregnancy recommended?

Maternal antibodies cross the placenta and protect the baby during the vulnerable first weeks before their own vaccinations begin. It is highly effective at preventing severe infant disease.

Do antibiotics stop the cough?

They reduce infectiousness and can shorten illness if started in the first week or two, but once the paroxysmal coughing phase is established they do little for the cough itself, which can last months.

Can vaccinated people still catch it?

Yes. Protection wanes over years, so adolescents and adults can develop a milder prolonged cough and unknowingly pass it to infants. This is why boosters and maternal vaccination matter.

References

  1. Centers for Disease Control and Prevention. Diseases and conditions.
  2. World Health Organization. Fact sheets.
  3. National Institutes of Health. Health information.

Important: Dard AI is not a medical device and does not diagnose, treat, or replace clinician judgement. This article is general information only. Always consult a qualified healthcare professional about diagnosis and treatment, and seek emergency care for severe or rapidly worsening symptoms.