title: Absolute Humidity Influences the Seasonal Persistence and Infectivity of Human Norovirus.
abstract: Norovirus (NoV) is one of the main causative agents of acute gastroenteritis worldwide. In temperate climates, outbreaks peak during the winter season. The mechanism by which climatic factors influence the occurrence of NoV outbreaks is unknown. We hypothesized that humidity is linked to NoV seasonality. Human NoV is not cultivatable, so we used cultivatable murine norovirus (MNV) as a surrogate to study its persistence when exposed to various levels of relative humidity (RH) from low (10% RH) to saturated (100% RH) conditions at 9 and 25°C. In addition, we conducted similar experiments with virus-like particles (VLPs) from the predominant GII-4 norovirus and studied changes in binding patterns to A, B, and O group carbohydrates that might reflect capsid alterations. The responses of MNV and VLP to humidity were somewhat similar, with 10 and 100% RH exhibiting a strong conserving effect for both models, whereas 50% RH was detrimental for MNV infectivity and VLP binding capacity. The data analysis suggested that absolute humidity (AH) rather than RH is the critical factor for keeping NoV infectious, with an AH below 0.007 kg water/kg air being favorable to NoV survival. Retrospective surveys of the meteorological data in Paris for the last 14 years showed that AH average values have almost always been below 0.007 kg water/kg air during the winter (i.e., 0.0046 ± 0.0014 kg water/kg air), and this finding supports the fact that low AH provides an ideal condition for NoV persistence and transmission during cold months.
authors.affiliation: UMR Procédés Alimentaires et Microbiologiques, AgroSup Dijon-Université de Bourgogne, Dijon, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Colas de la Noue
authors.affiliation: National Reference Center for Enteric Viruses, Public Hospital of Dijon, Dijon, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Estienney
authors.affiliation: Epidemiology and Infection Control Unit, Public Hospital of Dijon, Dijon, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Aho
authors.affiliation: UMR Procédés Alimentaires et Microbiologiques, AgroSup Dijon-Université de Bourgogne, Dijon, France.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Perrier-Cornet
authors.affiliation: National Reference Center for Enteric Viruses, Public Hospital of Dijon, Dijon, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: de Rougemont
authors.affiliation: National Reference Center for Enteric Viruses, Public Hospital of Dijon, Dijon, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Pothier
authors.affiliation: UMR Procédés Alimentaires et Microbiologiques, AgroSup Dijon-Université de Bourgogne, Dijon, France gael.belliot@u-bourgogne.fr patrick.gervais@u-bourgogne.fr.
authors.forename: Patrick
authors.initials: P
authors.lastname: Gervais
authors.affiliation: National Reference Center for Enteric Viruses, Public Hospital of Dijon, Dijon, France gael.belliot@u-bourgogne.fr patrick.gervais@u-bourgogne.fr.
authors.forename: Gaël
authors.initials: G
authors.lastname: Belliot
mesh_terms: D000818:Animals; D001789:Blood Group Antigens / Q000378:metabolism; D017250:Caliciviridae Infections / Q000453:epidemiology* / Q000821:virology*; D006801:Humans; D006813:Humidity; D051379:Mice; D050296:Microbial Viability; D029322:Norovirus / Q000502:physiology*; D010297:Paris; D011485:Protein Binding; D012621:Seasons; D013696:Temperature; D022701:Virosomes / Q000378:metabolism; D053585:Virus Attachment
chemical_list: D001789:Blood Group Antigens; D022701:Virosomes