Pertussis

• What is pertussis also known as?

  Whooping cough
• What is whooping cough?


  URTI

  Caused by Bordetella pertussis (gram negative bacteria)
• Who is vaccinated against whooping cough?


  Children

  Pregnant women (28-32 wks gestation)
• What are the RFs of pertussis?


  Unvaccinated or under-vaccinated

  Close contact with infected person
• What is the incubation period for pertussis?


  7-10 days
• In pertussis, how long after onset of symptoms are individuals still infectious?


  21 days
• What are the phases of pertusssis?

  3 different phases

  Early catarrhal

  • flu-like symptoms, dry cough, coryza, conjunctivitis, sore throat, mild fever
  • lasts for 1-2 weeks

  Spasmodic

  • dry, hacking cough - intensifies at night
  • 'whooping' cough during sustained periods of expiration
  • child may also vomit, faint, or cyanosed after severe coughing fits
  • lasts for 1-6 weeks

  Convalescent

  • cough may persist for 2-3 wks
• What are the signs & symptoms of pertussis?


  Cough

  Inspiratory whooping

  Coryza (rhinorrhoea, sneezing, a non-specific mild cough, and low-grade fever)

  Post-tussive vomiting
• What are the DDx of pertussis?


  Bronchiolitis

  Asthma

  Croup
• What are the Inx for pertussis?


  Obs

  Full Hx & examination

  Pernasal swabs (with PCR testing +/- culture)

  Anti-pertussis toxin IgG (in oral fluid)
• What is the management of pertussis?


  Infants < 6 mths -> should be admitted (as well as those with signif resp symptoms or complications)

  Notifiable disease

  Abx (typically macrolides, clarithromycin)

  Supportive care (analgesia/antipyretic, adequate fluid intake)

  Consider whether close contacts need prophylactic Abx or vaccination

  Do not go to nursery/school until 48 hrs after starting Abx or 21 days from onset of cough
• What are the possible complications of pertussis?


  Coughing fits -> subconjunctival haemorrhage, epistaxis, PTX, hernias & rib fractures

  Apnoea

  Secondary bacterial infections & pneumonia

  Cerebral hypoxia & seizures

  Encephalopathy

  Bronchiectasis

  Can be fatal (esp in < 6 months)
• Pathophys - pertussis

  Bordetella pertussis spread via resp droplets, airborne particles or contaminated fomites

  Bacteria adheres to ciliated resp epithelial cells -> produces toxins & mediators -> ciliary paralysis, tissue damage & inflammation -> increased lymphocytes (lymphocytosis), due to toxin

  B. pertussis can survive inside phagocytic & non-phagocytic cells

  Effects on disease progression & immune response is unclear
• What is shown in the image?

  Pernasal swab