Outbreak of Serratia marcescens postoperative infection traced to barbers and razors

SummaryBackgroundFourteen postoperative infections caused by Serratia marcescens were detected in patients on the neurosurgical wards and spinal surgery ward of a 2640-bed hospital between 26th December 2012 and 5th June 2013.AimTo investigate the source of the outbreak, identify risk factors and implement infection control measures.MethodsCultures were collected from healthcare workers and potential environmental sources. S. marcescens isolates were characterized by antibiotic susceptibility testing and pulsed-field gel electrophoresis (PFGE). A retrospective case–control study was performed to identify the risk factors.FindingsThe outbreak involved 14 patients, five of whom required more than one surgical procedure. S. marcescens was isolated from cerebrospinal fluid, brain tissue, sputum and other secretions. S. marcescens was also cultured from samples taken from the hands of two barbers and their razors. Exposure to the two barbers [odds ratio (OR) 78.0, P < 0.0001] and wound drainage (OR 4.889, P = 0.028) were risk factors. Pre-operative shaving by the barbers was the only independent risk factor (OR 78.0, P < 0.0001). Isolates of S. marcescens from patients, barbers and razors were indistinguishable by PFGE and antibiotic susceptibility pattern. The outbreak ended after removal of the implicated barbers, extensive re-inforcement of infection control procedures and re-education.ConclusionThese results underscore the risk of postoperative infection associated with pre-operative wet shaving.