Cell Phones and Acinetobacter Transmission

To the Editor: Nosocomial Acinetobacter baumannii is commonly acquired through cross-transmission because of its propensity to survive in the hospital environment and persistently contaminate fomites. Since cell phones are used increasingly by health personnel worldwide, we sought to determine their role in noso-comial transmission of multidrug-resistant (MDR) A. baumannii. The study was conducted in a terti-ary-care hospital in Israel, where MDR Acinetobacter spp. is endemic. Cell phones are used by personnel both for private communication and instead of traditional pagers. During 2002, 124 personnel (71 physicians, 54 nurses) were screened randomly for Acinetobacter spp. in a point-prevalence study; samples from hands of 119 personnel and 124 cell phones were cultured simultaneously for 2 months. Swabs from the back and sides of the cell phones were cultured. Cultures of hand samples were done by using the broth-bag technique (1). To assess cross-transmission between hands, cell phones, and patients, we studied 2 additional Acinetobacter spp. culture cohorts, nosocomial blood isolates from 2000 to 2002, and axilla and groin Acinetobacter spp. skin colonization in an intensive care unit (ICU) during 2002. Cohorts represent wards in which 73% of study personnel worked. Isolates were identified by the ID20NE system (bioMerieux, Marcy l'Etoile, France) without differentiation between A. baumannii and species 3 and 13TU. Antimicrobial susceptibility was determined for aminoglycosides, penicillins, cepha-losporins, carbapenems, fluoro-quinolones, tetracyclines, polymyxin E, and ampicillin/sulbactam by using disk diffusion according to Clinical and Laboratory Standards Institute guidelines (2). MDR was defined as resistance >3 different classes. Genotypic analysis of isolates from all cohorts was performed using pulsed-field gel electrophoresis. Chromosomal DNA was digested with ApaI and analyzed by using a CHEF-DRIII apparatus Strain relatedness was interpreted according to consensus (3). Isolates showing an identical banding pattern were considered indistinguishable, and those showing differences of 3 bands were considered closely related. Study personnel were assigned to medical (22%), surgical (44%), pedi-atric (23%), and ICU (11%) wards. The respective contamination rate with Acinetobacter spp. was 27%, 7.4%, 7.4%, and 0% for cell phones and 24%, 22%, 14%, and 41% for personnel hands. Of 30 hand and 15 cell phone cultures positive for Acinetobacter spp., 17% and 20%, respectively, were MDR. Both hand and cell phone cultures of 3 personnel were positive (unrelated strains). Cell phone and hand isolates exhibited substantial clonal diversity. Acinetobacter spp. transmission (including MDR strains) was documented between hands, as well as between cell phones and hands, of different persons …