Epidemiology of Clostridium difficile during norovirus outbreaks

ABSTRACT: It has been reported and was observed at HoEFT last winter that during norovirus outbreaks the incidence of Clostridium difficile increases. However, there is limited understanding of the increased incidence of C. difficile at times of other gastrointestinal infections. It is hypothesized that it may be due to an increased number of specimens being tested, with increased detection of CDT in patients who, in non-outbreak periods, would not normally have been tested for C. difficile toxin. Other possibilities are that there maybe due to an interaction between C. difficile and norovirus increasing the chance of clostridial toxin production, or that there is an increased risk of C. difficile transmission due to the norovirus. The principal aim of the project is to determine the epidemiology of C. difficile and norovirus during outbreaks of confirmed norovirus on a ward. Detection of C. difficile at HoEFT currently relies upon ELISAs which have been shown to have low sensitivities. Real-time PCR methods are available which have shown to have a high degree of concordance with toxigenic culture (the current gold standard). This project will also include an evaluation of both proprietary and in-house real-time PCR methods for possible introduction into routine testing procedures.