Noroviruses: Simple Detection for Complex Epidemiology

Abstract

Nearly 25 years ago, Kaplan et al. [1] developed criteria for recognizing outbreaks of gastroenteritis due to norovirus. In those days, the state-of-the-art diagnostic test for these ubiquitous and ecologically clever RNA viruses was transmission electron microscopy. Preparing stool specimens for analysis under the microscope is not a particularly fulfilling exercise, given the frustratingly low sensitivity of visualizing the small round structured virus particles [2]. The criteria of Kaplan et al. responded to these limitations in diagnostic capability. Of course, in the intervening years, tremendous progress has been made in monoclonal antibody technology and nucleic acid detection (e.g., [3, 4]). Given all of the diagnostic advances of the past 2 decades, it is both remarkable and a little bit sad that the criteria of Kaplan et al. remain such a relevant tool for recognizing outbreaks caused by norovirus. Turcios et al. [5] have confirmed, on a much larger and more varied data set than Kaplan et al. [ 1] had at their disposal, what these earlier investigators originally suggested. These criteria are wonderfully specific-99%-and reasonably sensitive-