Pertussis outbreak in paediatric cardiac surgery

Introduction: Although pertussis immunisation is recommended for paediatric health care workers (HCW), vaccine uptake remains low and outbreak may still occur. In 2008, a 6 month-old cardiac patient originating from Algeria, developed severe pertussis and was admitted to PICU.
Objective: To describe infection control intervention during a pertussis oubreak in our 16 beds paediatric cardiac surgery and 14 beds PICU unit.
Methods: Confirmed pertussis case : Positive PCR on nasopharyngeal aspirate (NPA). HCW, patients and parents were interviewed to search for cough and pertussis vaccine status. B. pertussis PCR detection was performed in all unvaccinated direct contact of index case. Serology was performed in unvaccinated contact HCW and parents. Immunisation was proposed to all HCW. Contact patients and parents were given antibiotic prophylaxis and cardiac surgery unit was quarantined for 5 days. Active surveillance was performed for 10 weeks.
Résultats: 4/61 and 19/54 HCW had received a pertussis vaccine in surgery and ICU respectively. 151 NPA were performed and 7 (4,6 %) confirmed cases have been identified (2 children, 2 nurses and 3 mothers), 2 of which were symptomatic. No cases were acquired in ICU. No children were identified with pertussis symptoms and 7 HCW had symptoms of cough, one was paroxysmal and one prolonged. No serology was positive (55 performed). Antibiotics treatments or prophylaxis were administered to 38 persons. 82 HCW were vaccinated, 29 and 18 from surgery and ICU respectively.
Conclusions: Pertussis outbreak control required drastic containment measures. Pertussis immunisation of HCW should be actively recommanded to avoid outbreaks.