Infection control for norovirus

Abstract

Norovirus infections are notoriously difficult to prevent and control, owing to their low infectious dose, high shedding titre, and environmental stability. The virus can spread through multiple transmission routes, of which person-to-person and foodborne are the most important. Recent advances in molecular diagnostics have helped to establish norovirus as the most common cause of sporadic gastroenteritis and the most common cause of outbreaks of acute gastroenteritis across all ages. In this article, we review the epidemiology and virology of noroviruses, and prevention and control guidelines, with a focus on the principles of disinfection and decontamination. Outbreak management relies on sound infection control principles, including hand hygiene, limiting exposure to infectious individuals, and thorough environmental decontamination. Ideally, all infection control recommendations would rely on empirical evidence, but a number of challenges, including the inability to culture noroviruses in the laboratory and the challenges of outbreak management in complex environments, has made it difficult to garner clear evidence of efficacy in certain areas of infection control. New experimental data on cultivable surrogates for human norovirus and on environmental survivability and relative resistance to commonly used disinfectants are providing new insights for further refinining disinfection practices. Finally, clinical trials are underway to evaluate the efficacy of vaccines, which may shift the current infection control principles to more targeted interventions.

Advances in Laboratory Methods for Detection and Typing of Norovirus

“…Therefore, rapid laboratory diagnosis is a critical tool to guide controlling norovirus outbreaks by choosing the most appropriate intervention and control practices such as enhanced cleaning and disinfection protocols, isolation, grouping patients based on symptoms, exclusion of symptomatic staff members or food handlers, or, ultimately, closing of units in hospitals (38). Over the last decade, significant progress has been made in the development of diagnostic methods for the routine detection of human noroviruses.…”

Norovirus

“…Many of these results are summarized in the HICPAC (Healthcare Infection Control Practices Advisory Committee) guidelines for the prevention and control of norovirus gastroenteritis outbreaks in health care settings published in 2011 and in a recent review of norovirus infection control measures (233,234). The three main strategic areas included staff and patient policy development, hand hygiene, and proper environmental disinfection.…”

“…In general, hypochlorite (bleach) solutions of at least 1,000 ppm are the preferred disinfectants for contaminated surfaces and objects and must be used for an appropriate contact time (233,266,267). Quaternary ammonium compounds are also under investigation but have been somewhat less effective than bleach solutions (234,267). Both the type of sanitizer and method of application can have an impact on virucidal success (268).…”

Monthly Distribution of Norovirus and Sapovirus Causing Viral Gastroenteritis in Thailand

“…NoV can be divided into 5 distinct genogroups, GI to GV: the two major ones, GI and GII, and GIV have been shown to infect humans. The GI and GII strains consist of at least 9 and 22 genotypes (GI.1-GI.9 and GII.1-GII.22), respectively (2,3). GII.4 has been the most prevalent genotype in recent years, although the emergence and predominant distribution of GII.17 have been reported recently in Asia (4).…”