title: Comparison of internal process control viruses for detection of food and waterborne viruses.
abstract: Enteric viruses are pathogens associated with food- and waterborne outbreaks. The recovery of viruses from food or water samples is affected by the procedures applied to detect and concentrate them. The incorporation of an internal process control virus to the analyses allows monitoring the performance of the methodology. The aim of this study was to produce a recombinant adenovirus (rAdV) and apply it together with bacteriophage PP7 as process controls. The rAdV carries a DNA construction in its genome to differentiate it from wild-type adenovirus by qPCR. The stability of both control viruses was evaluated at different pH conditions. The rAdV was stable at pH 3, 7, and 10 for 18 h. PP7 infectious particles were stable at pH 7 and showed a 2.14 log reduction at pH 10 and total decay at pH 3 after 18 h. Three virus concentration methods were evaluated: hollow-fiber tap water ultrafiltration, wastewater ultracentrifugation, and elution-PEG precipitation from lettuce. Total and infectious viruses were quantified and their recoveries were calculated. Virus recovery for rAdV and PP7 by ultrafiltration showed a wide range (2.10-84.42 and 13.54-84.62%, respectively), whereas that by ultracentrifugation was 5.05-13.71 and 6.98-13.27%, respectively. The performance of ultracentrifugation to concentrate norovirus and enteroviruses present in sewage was not significantly different to the recovery of control viruses. For detection of viruses from lettuce, genomic copies of PP7 were significantly more highly recovered than adenovirus (14.74-18.82 and 0.00-3.44%, respectively). The recovery of infectious virus particles was significantly affected during sewage ultracentrifugation and concentration from lettuce. The simultaneous use of virus controls with dissimilar characteristics and behaviors might resemble different enteric viruses.
authors.affiliation: Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina. dblanco@ffyb.uba.ar.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina. dblanco@ffyb.uba.ar.
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Blanco Fernández
authors.affiliation: Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina.|Ministerio de Ciencia y Tecnología, Agencia Nacional de Promoción Científica y Tecnológica, Godoy Cruz 2370, 1425, Buenos Aires, Argentina.
authors.forename: Melina Elizabeth
authors.initials: ME
authors.lastname: Barrios
authors.affiliation: Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina.
authors.forename: Robertina Viviana
authors.initials: RV
authors.lastname: Cammarata
authors.affiliation: Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina.
authors.forename: Carolina
authors.initials: C
authors.lastname: Torres
authors.affiliation: Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina.|Instituto de Biotecnología, INTA, Nicolás Repetto y de los Reseros s/n, 1686, Hurlingham, Buenos Aires, Argentina.
authors.forename: Oscar Alberto
authors.initials: OA
authors.lastname: Taboga
authors.affiliation: Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113, Buenos Aires, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, 1425, Buenos Aires, Argentina.
authors.forename: Viviana Andrea
authors.initials: VA
authors.lastname: Mbayed
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000502:physiology; D004770:Enterovirus / Q000235:genetics / Q000302:isolation & purification; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D018545:Lactuca / Q000821:virology; D017909:Levivirus / Q000235:genetics / Q000302:isolation & purification; D029322:Norovirus / Q000235:genetics / Q000302:isolation & purification; D017105:Pseudomonas Phages / Q000235:genetics / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction; D012722:Sewage / Q000821:virology; D014461:Ultracentrifugation; D014462:Ultrafiltration; D014780:Viruses / Q000235:genetics / Q000302:isolation & purification*; D014871:Water Microbiology
chemical_list: D012722:Sewage
keywords: Hollow fiber ultrafiltration; Internal process control virus; Lettuce; Sewage; Ultracentrifugation; Virus recovery