Two consecutive outbreaks of Acinetobacter baumanii 1-a in a burn Intensive Care Unit for adults

Abstract 

Acinetobacter baumanii is generally a highly antibiotic resistant micro-organism that can be easily transmitted between inpatients of ICUs. We report two consecutive outbreaks of A. baumanii in a burn ICU. Material and methods: All patients with ICU-stay greater than 2 days were subject to a strict epidemiological surveillance after admission, recording age, sex, TSBA, etc. and follow-up data such as antibiotherapy, instrumentation, infections, etc. We also monitored the microbial flora evolution and their resistance to antibiotic by weekly cultures of pharynx, rectum, skin (healthy and burned), etc. Because of an “epidemic” microorganism, infection control procedures, were increased. We studied the colonization by other prevalent microorganisms: MR-S. aureus and Pseudomonas aeruginosa. Results: Seventy-two burn patients were followed in 1 year. Only 4.1% were infected at some site by A. baumanii, but 1/3 of patients were colonized by this microorganism, distributed in two outbreaks, one in the first trimester, after admission in the Unit of two non-burned and colonized patients (from another ICU). The second epidemic began in July and probably was due to transitory colonization of skin or fomites by health personnel working in both ICUs. All the isolates (from both ICUs) of A. baumanii were identical by PFGE. The length of hospital stay was the main risk factor for colonization. P. aeruginosa and MR-S. aureus showed a tendency to be endemo-epidemic at all times. Conclusion: Our cross colonization control measures showed a limited efficacy our burn patients. Therefore, we must impede the introduction to burn ICUs of epidemic microorganisms by colonized patients or heath personnel by restriction of admission of A. baumanii colonized patients from other ICUs (if the treatment can be administered in this ICU) and by strict disinfection/antiseptic procedures.

Keywords:  Consecutive outbreaks, Acinetobacter baumanii 1-a, Intensive Care Unit