Investigation of a Clostridium difficile associated disease outbreak at Nanaimo General Regional Hospital August 2008

NGRH experienced an outbreak of Clostridium difficile associated illness (CDI) which in retrospect started in June of 2008 and was decreasing by mid September 2008. On August 2008, the Vancouver Island Health Authority Infection Prevention and Control Program requested the assistance of the BC Centre for Disease Control in conducting an in-depth epidemiologic investigation of the outbreak in order to identify any modifiable factors to help prevent recurrence of CDI outbreaks in the future. At the time of this review in late August there were 64 confirmed cases of CDI with 8 deaths in the confirmed cases. Not all deaths were due to CDI and are being reviewed to determine the role that CDI played. Rates of CDI peaked at 22 cases/1000 admissions in August of 2008; over four times the average rate seen in Canada and significantly higher than rates in NGRH over the previous two years which had ranged from 1.3-2.4 /1000 admissions. Enhanced infection control practices and a concerted effort to identify and isolate cases appropriately led to the outbreak waning in late August/early September. The BC Centre for Disease Control was asked to conduct an infection control and epidemiologic review of this outbreak to assist NGRH in understanding the precipitating factors and the course of the outbreak in order to more fully appreciate the measures they needed to take to prevent further outbreaks. An infection control review was conducted on August 22 and an interim report was prepared for the facility; two epidemiologists (from BCCDC and the Public Health Agency of Canada) then spent a week from August 25-29 onsite reviewing the case records and procedures at the facility to develop an epidemiologic picture of the outbreak.