Pertussis (Whooping Cough)

Pt with no h/o DTaP or TDaP vaccination presents with cough and intermittent apneic episodes. Cough started > 2 weeks ago. Current symptoms include coughing paroxysms followed by whooping sound and emesis. Low grade fever on exam.

• Cough duration

  • < 4 weeks: Obtain PCR and culture

  • > 4 weeks: Obtain serology

• CXR shows no foreign body

• Treatment

  • Cough duration < 3 weeks: Start azithromycin (see notes for dosing)

  • Cough duration < 6 weeks and pregnant pt with small infant who works in health care: Start azithromycin (see notes for dosing)

  • Start post-exposure prophylaxis for all close contacts

• Pt and parents advised that pertussis is highly contagious

Notes

• Due to risk of transmission, antibiotics are started within 6 weeks of cough for a pt who is pregnant, anyone working with infants, and healthcare workers

• Close contact prophylaxis

  • Close contact definition: Regular, face-to-face exposure within 3 feet of the symptomatic patient.

  • Threshold for "regular" can change based on the individual’s risk for contracting the illness, e.g. would be lower for immunocompromised individuals.

• Azithromycin dosing

  • Age 1-5 month: 10 mg/kg x 5 days

  • Children 6+ months: 10 mg/kg on day 1 then 5 mg/kg days 2-5

  • Adults: 500 mg on day 1 then 250 mg days 2-5