Background: During a hospital obstetric rotation, a medical student demonstrated classic symptoms of pertussis. The diagnosis was confirmed by isolation of Bordetella pertussis. Because this exposure occurred in a high-risk hospital setting, control measures were undertaken to prevent transmission and illness.
Objectives: To identify secondary cases of pertussis, to determine compliance with chemoprophylaxis recommendations, and to monitor for adverse events associated with chemoprophylaxis following a hospital exposure to pertussis.
Patients: More than 500 individuals were potentially exposed, including 168 neonates; antimicrobial chemoprophylaxis was administered to 281 individuals. Fifty-eight neonates and 194 adults began azithromycin chemoprophylaxis; 18 neonates and 2 adults began erythromycin chemoprophylaxis.
Methods: Active surveillance was instituted for (1) secondary cases of pertussis among healthcare coworkers, obstetric patients, their neonates, and labor companions and (2) antibiotic compliance and tolerance.
Results: No secondary cases of pertussis were confirmed by laboratory tests; however, 26 suspected cases and 5 clinically compatible cases were identified. Antibiotic courses were completed by 95% of the individuals who initiated therapy. Neonates taking azithromycin had statistically significantly less gastrointestinal distress compared with neonates taking erythromycin (12% vs 50%; P = .002); there were no cases of infantile hypertrophic pyloric stenosis.
Conclusions: Although it was not possible to assess the effectiveness of the antibiotic regimens, the lack of laboratory-confirmed secondary cases suggests control measures were successful. Data from the 58 neonates who received azithromycin suggest it may be well tolerated in this age group.