Analysis of Costs Attributable to an Outbreak of Severe Acute Respiratory Syndrome at a French Hospital
Infection control and hospital epidemiology
Other potential reservoirs (eg, shaving cream, povidoneiodine solution, water supplies, and an alcohol-based mouthwash) were culture negative for B. cepacia. Samples were obtained from unopened bottles of mouthwash distributed around the hospital that belonged to different batches, and the samples were cultured. Batches diswere highly contaminated. No other samples were available for analysis. The distribution of contaminated batches matched the substantial increase in the incidence of B.
... a infection or colonization. Strains from 5 patients and 6 mouthwash samples were submitted for identification to our reference center (National Center of Microbiology, Health Institute Carlos III, Majadahonda, Madrid, Spain). Pulsed-field gel electrophoresis of Xbal-digested genomic DNA was performed with a Chief DR-III system (Bio-Rad) according to conditions described elsewhere, 10 with several modifications. Briefly, electrophoresis was carried out in a 1.2% agarose gel for 22 hours at 6 V/cm with pulse times ranging from 5 to 35 seconds. Molecular mass markers were concatameters of phage X New England (Biolabs, UK). Electrophoretic patterns showed that all the strains were identical (Figure) . On July 18, the use of the mouthwash product in our hospital was discontinued, and the last isolate of B. cepacia was obtained on July 22, 2005. The methods of production and distribution and the extent of use of this mouthwash in other hospitals are now being investigated by the Spanish Department of Health. At the moment, no information is available on the rate of B. cepacia infection or colonization at other hospitals that used the same product distributed by the same company as at our hospital. Our findings strongly suggest that intrinsically contaminated alcohol-free mouthwash solution was the source of this large outbreak involving predisposed adults in ICU. To date, 2 similar outbreaks in which B. cepacia was isolated from culture of respiratory tract specimens from patients without cystic fibrosis have been traced to intrinsically contaminated alcohol-free mouthwash in North America. 7 ' 8 More-thorough surveillance of microbiological contamination of alcohol-free products used in adults predisposed to infection should be mandatory. These findings highlight the importance of hospital surveillance and investigation of unusual clusters of infection and colonization to promptly identify unexpected sources of pathogens and to protect patients at risk.