title: Aetiology of influenza-like illness in adults includes parainfluenzavirus type 4.
abstract: Influenza viruses cause significant morbidity and mortality in adults each winter. At the same time, other respiratory viruses circulate and cause respiratory illness with influenza-like symptoms. Human respiratory syncytial virus (HRSV), human parainfluenza viruses (HPIV) and human metapneumovirus have all been associated with morbidity and mortality in adults, including nosocomial infections. This study evaluated 154 respiratory specimens collected from adults with influenza-like/acute respiratory illness (ILI) seen at the Edward Hines Jr VA Hospital, Hines, IL, USA, during two successive winters, 1998-1999 and 1999-2000. The samples were tested for ten viruses in two nested multiplex RT-PCRs. One to three respiratory viruses were detected in 68 % of the samples. As expected, influenza A virus (FLU-A) infections were most common (50 % of the samples), followed by HRSV-A (16 %). Surprisingly, HPIV-4 infections (5.8 %) were the third most prevalent. Mixed infections were also relatively common (11 %). When present, HPIV infections were approximately three times more likely to be included in a mixed infection than FLU-A or HRSV. Mixed infections and HPIV-4 are likely to be missed using rapid diagnostic tests. This study confirms that ILI in adults and the elderly can be caused by HRSV and HPIVs, including HPIV-4, which co-circulate with FLU-A.
authors.affiliation: Department of Immunology & Microbiology, College of Medicine, Rush University, 1653 W. Congress Parkway, Chicago, IL 60612, USA.|Sisli Etfal Training and Research Hospital, Department of Infectious Disease and Clinical Microbiology, Sisli, Istanbul, Turkey.
authors.forename: Hatice
authors.initials: H
authors.lastname: Hasman
authors.affiliation: Section of Infectious Diseases, Department of Medicine, Edward Hines Jr VA Hospital, Hines, IL 60141, USA.
authors.forename: Constance T
authors.initials: CT
authors.lastname: Pachucki
authors.affiliation: Section of Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Department of Pediatrics, Ohio State University College of Medicine, 700 Children's Drive, Columbus, OH 43205, USA.
authors.forename: Arife
authors.initials: A
authors.lastname: Unal
authors.affiliation: Department of Medical Technology, College of Health Sciences, Rush University, 1653 W. Congress Parkway, Chicago, IL 60612, USA.
authors.forename: Diep
authors.initials: D
authors.lastname: Nguyen
authors.affiliation: Department of Medical Technology, College of Health Sciences, Rush University, 1653 W. Congress Parkway, Chicago, IL 60612, USA.
authors.forename: Troy
authors.initials: T
authors.lastname: Devlin
authors.affiliation: Division of Immunology, Graduate College, Rush University, 1653 W. Congress Parkway, Chicago, IL 60612, USA.|Section of Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Department of Pediatrics, Ohio State University College of Medicine, 700 Children's Drive, Columbus, OH 43205, USA.|Department of Immunology & Microbiology, College of Medicine, Rush University, 1653 W. Congress Parkway, Chicago, IL 60612, USA.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Peeples
authors.affiliation: Division of Immunology, Graduate College, Rush University, 1653 W. Congress Parkway, Chicago, IL 60612, USA.|Section of Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Department of Pediatrics, Ohio State University College of Medicine, 700 Children's Drive, Columbus, OH 43205, USA.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Kwilas
mesh_terms: D000328:Adult; D000818:Animals; D002460:Cell Line; D004285:Dogs; D006801:Humans; D007251:Influenza, Human / Q000821:virology*; D029482:Parainfluenza Virus 4, Human / Q000235:genetics / Q000302:isolation & purification*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012621:Seasons