Pertussis

Question 1

Clinical Criteria of Pertussis

Answer 1

Cough Lasting > 2 weeks without a more likely diagnosis with at least one of the following
- Paroxysms of coughing
- Inspiratory whoop
- Post-tussive vomiting
- For infants < 1 yo, apnoea with or without cyanosis

Question 2

Laboratory Criteria of pertussis

Answer 2

Isolation of B. pertussis from a clinical specimen within 2 weeks
Positive PCR for pertussis from a clinical specimen within 4 weeks
If > 4 weeks since onset of symptoms, only serology is useful and swabs will return negative.

Question 3

Antibiotic treatment for Pertussis

Answer 3

Azithromycin 500mg (10mg/kg) PO OD Day 1, Follow with Azithromycin 250mg (5mg/kg) PO OD for 4 further days
Neonate? 10mg/kg PO OD x 5 days
or Clarithromycin 500mg (7.5mg/kg) PO BD x 7 days

2nd line
- Trimethoprim + Sulfamethoxazole 160+800mg (4+20mg/kg) PO BD x 7 days

Recommended if diagnosis made within 3 weeks of onset of symptoms

Question 4

Public health measures after identification of case and

Answer 4

• Notify local public health unit
• Contact tracing (individuals within 1 meter for more than 1 hour over last 3 weeks
• Avoid close contact with others until 5 days after commencement of PO Abx