title: Assessment of airborne virus contamination in wastewater treatment plants.
abstract: BACKGROUND
  Occupational exposure to bioaerosols in wastewater treatment plants (WWTP) and its consequence on workers' health are well documented. Most studies were devoted to enumerating and identifying cultivable bacteria and fungi, as well as measuring concentrations of airborne endotoxins, as these are the main health-related factors found in WWTP. Surprisingly, very few studies have investigated the presence and concentrations of airborne virus in WWTP. However, many enteric viruses are present in wastewater and, due to their small size, they should become aerosolized. Two in particular, the norovirus and the adenovirus, are extremely widespread and are the major causes of infectious gastrointestinal diseases reported around the world. The third one, hepatitis E virus, has an emerging status.
  
  
  OBJECTIVE
  This study׳s objectives were to detect and quantify the presence and concentrations of 3 different viruses (adenovirus, norovirus and the hepatitis E virus) in air samples from 31 WWTPs by using quantitative polymerase chain reaction (qPCR) during two different seasons and two consecutive years.
  
  
  RESULTS
  Adenovirus was present in 100% of summer WWTP samples and 97% of winter samples. The highest airborne concentration measured was 2.27 × 10(6) genome equivalent/m(3) and, on average, these were higher in summer than in winter. Norovirus was detected in only 3 of the 123 air samples, and the hepatitis E virus was not detected.
  
  
  CONCLUSIONS
  Concentrations of potentially pathogenic viral particles in WWTP air are non-negligible and could partly explain the work-related gastrointestinal symptoms often reported in employees in this sector.
authors: Institute for Work and Health (IST), University of Lausanne and University of Geneva, Route de la Corniche 2, 1066 Epalinges-Lausanne, Switzerland. Electronic address: Frederic.Masclaux@unil.ch.
authors: Frédéric G
authors: FG
authors: Masclaux
authors: Occupational and Environmental Medicine Unit, Med. Poliklinik USZ, Rämistrasse 100, 8091 Zürich, Switzerland. Electronic address: Philipp.Hotz@usz.ch.
authors: Philipp
authors: P
authors: Hotz
authors: Occupational and Environmental Medicine Unit, Med. Poliklinik USZ, Rämistrasse 100, 8091 Zürich, Switzerland.
authors: Drita
authors: D
authors: Gashi
authors: Institute for Work and Health (IST), University of Lausanne and University of Geneva, Route de la Corniche 2, 1066 Epalinges-Lausanne, Switzerland.
authors: Dessislava
authors: D
authors: Savova-Bianchi
authors: Institute for Work and Health (IST), University of Lausanne and University of Geneva, Route de la Corniche 2, 1066 Epalinges-Lausanne, Switzerland. Electronic address: Anne.Oppliger@hospvd.ch.
authors: Anne
authors: A
authors: Oppliger
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D000391:Air Microbiology; D004731:Endotoxins / Q000009:adverse effects / Q000235:genetics; D016752:Hepatitis E virus / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D029322:Norovirus / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D060888:Real-Time Polymerase Chain Reaction; D018505:Waste Management
chemical_list: D004731:Endotoxins
keywords: Adenovirus; Bioaerosol; Hepatitis E virus; Norovirus; Occupational health; Sewage