title: Inactivation of a foodborne norovirus outbreak strain with nonthermal atmospheric pressure plasma.
abstract: Human norovirus (NoV) is the most frequent cause of epidemic nonbacterial acute gastroenteritis worldwide. We investigated the impact of nonthermal or cold atmospheric pressure plasma (CAPP) on the inactivation of a clinical human outbreak NoV, GII.4. Three different dilutions of a NoV-positive stool sample were prepared and subsequently treated with CAPP for various lengths of time, up to 15 min. NoV viral loads were quantified by quantitative real-time reverse transcription PCR (RT-qPCR). Increased CAPP treatment time led to increased NoV reduction; samples treated for the longest time had the lowest viral load. From the initial starting quantity of 2.36 × 10(4) genomic equivalents/ml, sample exposure to CAPP reduced this value by 1.23 log10 and 1.69 log10 genomic equivalents/ml after 10 and 15 min, respectively (P < 0.01). CAPP treatment of surfaces carrying a lower viral load reduced NoV by at least 1 log10 after CAPP exposure for 2 min (P < 0.05) and 1 min (P < 0.05), respectively. Our results suggest that NoV can be inactivated by CAPP treatment. The lack of cell culture assays prevents our ability to estimate infectivity. It is possible that some detectable, intact virus particles were rendered noninfectious. We conclude that CAPP treatment of surfaces may be a useful strategy to reduce the risk of NoV transmission in crowded environments.
  
  
  OBJECTIVE
  Human gastroenteritis is most frequently caused by noroviruses, which are spread person to person and via surfaces, often in facilities with crowds of people. Disinfection of surfaces that come into contact with infected humans is critical for the prevention of cross-contamination and further transmission of the virus. However, effective disinfection cannot be done easily in mass catering environments or health care facilities. We evaluated the efficacy of cold atmospheric pressure plasma, an innovative airborne disinfection method, on surfaces inoculated with norovirus. We used a clinically relevant strain of norovirus from an outbreak in Germany. Cold plasma was able to inactivate the virus on the tested surfaces, suggesting that this method could be used for continuous disinfection of contaminated surfaces. The use of a clinical strain of norovirus strengthens the reliability of our results as it is a strain relevant to outbreaks in humans.
authors.affiliation: Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
authors.forename: Birte
authors.initials: B
authors.lastname: Ahlfeld
authors.affiliation: Max Planck Institute for Extraterrestrial Physics, Garching, Germany.
authors.forename: Yangfang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Boulaaba
authors.affiliation: Central Institute of the Bundeswehr Medical Service Kiel, Kronshagen, Germany.
authors.forename: Alfred
authors.initials: A
authors.lastname: Binder
authors.affiliation: Central Institute of the Bundeswehr Medical Service Kiel, Kronshagen, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schotte
authors.affiliation: Max Planck Institute for Extraterrestrial Physics, Garching, Germany.
authors.forename: Julia L
authors.initials: JL
authors.lastname: Zimmermann
authors.affiliation: Max Planck Institute for Extraterrestrial Physics, Garching, Germany.
authors.forename: Gregor
authors.initials: G
authors.lastname: Morfill
authors.affiliation: Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany guenter.klein@tiho-hannover.de.
authors.forename: Günter
authors.identifier: http://orcid.org/0000-0003-1931-2701
authors.initials: G
authors.lastname: Klein
mesh_terms: D017250:Caliciviridae Infections / Q000453:epidemiology / Q000821:virology*; D004196:Disease Outbreaks; D005243:Feces / Q000737:chemistry; D005517:Foodborne Diseases / Q000453:epidemiology / Q000821:virology*; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D029322:Norovirus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D058626:Plasma Gases / Q000494:pharmacology*; D013242:Sterilization / Q000295:instrumentation / Q000379:methods*; D038301:Virus Inactivation / Q000187:drug effects*
chemical_list: D058626:Plasma Gases