Increase in reported Clostridium difficile cases as unintended consequence of enhanced norovirus testing

摘要

Madam, Norovirus is the most frequent cause of nosocomial gastroenteritis outbreaks. There are no specific symptoms that allow a reliable diagnosis but, when large outbreaks occur, the descriptive criteria used by Kaplan have a moderate sensitivity and high specificity. However, the Kaplan criteria are a poor tool for practical timely infection control. First, they can only be applied when a number of cases have occurred. Second, a failure to make individual diagnoses at least for 'atypical cases', or cases occurring towards the end of an outbreak, or cases in new and unexpected locations, may result in the unnecessary introduction or prolongation of ward closures. The Kaplan criteria are often complemented with the selective submission of stools to regional centres for norovirus poly-merase chain reaction (PCR) testing. In our institution when testing was done via a nearby reference centre, the turnaround time was 10 days: this meant that testing was not an effective infection control tool.