• 1
    Jennings LC, Anderson TP, Beynon KA et al. Incidence and characteristics of viral community-acquired pneumonia in adults. Thorax 2008; 63:4248.
  • 2
    Jain S, Kamimoto L, Bramley AM et al. Hospitalized patients with 2009 H1N1 influenza in the United States, April–June 2009. New Engl J Med 2009; 361:19351944.
  • 3
    Mallia P, Johnston SL. How viral infections cause exacerbation of airway diseases. Chest 2006; 130:12031210.
  • 4
    Thompson WW, Shay DK, Weintraub E et al. Influenza-associated hospitalizations in the United States. JAMA. 2004; 292:13331340.
  • 5
    Thompson WW, Shay DK, Weintraub E et al. Mortality associated with influenza and respiratory syncytial virus in the United States. JAMA. 2003; 289: 179186.
  • 6
    Templeton KE, Scheltinga SA, van den Eeden WC, Graffelman AW, van den Broek PJ, Claas EC. Improved diagnosis of the etiology of community-acquired pneumonia with real-time polymerase chain reaction. Clin Infect Dis 2005; 41:345351.
  • 7
    GEN-PROBE. Prodesse ProFlu+ 2010. Available from: (Accessed 14 November 2013).
  • 8
    Luminex Molecular Diagnostics. xTAG RVP 2009. Available from: (Accessed 8 November 2013).
  • 9
    Kumar D, Michaels MG, Morris MI et al. Outcomes from pandemic influenza A H1N1 infection in recipients of solid-organ transplants: a multicentre cohort study. Lancet Infect Dis 2010; 10:521526.
  • 10
    Yu H, Feng Z, Uyeki TM et al. Risk factors for severe illness with 2009 pandemic influenza A (H1N1) virus infection in China. Clin Infect Dis 2011; 52:457465.
  • 11
    Lee N, Choi KW, Chan PK et al. Outcomes of adults hospitalised with severe influenza. Thorax 2010; 65:510515.
  • 12
    Winther B, Hayden FG, Hendley JO. Picornavirus infections in children diagnosed by RT-PCR during longitudinal surveillance with weekly sampling: Association with symptomatic illness and effect of season. J Med Virol 2006; 78:644650.
  • 13
    Litwin CM, Bosley JG. Seasonality and prevalence of respiratory pathogens detected by multiplex PCR at a tertiary care medical center. Arch Virol 2014; 159:6572.
  • 14
    Johnstone J, Majumdar SR, Fox JD, Marrie TJ. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 2008; 134:11411148.
  • 15
    Simonsen L, Clarke MJ, Williamson GD, Stroup DF, Arden NH, Schonberger LB. The impact of influenza epidemics on mortality: introducing a severity index. Am J Public Health 1997; 87:19441950.
  • 16
    Galindo-Fraga A, Ortiz-Hernandez AA, Ramirez-Venegas A et al. Clinical characteristics and outcomes of influenza and other influenza-like illnesses in Mexico City. Int J Infect Dis 2013; 17:e510e517.
  • 17
    Bakaletz LO. Viral potentiation of bacterial superinfection of the respiratory tract. Trends Microbiol 1995; 3:110114.
  • 18
    Ishizuka S, Yamaya M, Suzuki T et al. Effects of rhinovirus infection on the adherence of Streptococcus pneumoniae to cultured human airway epithelial cells. J Infect Dis 2003; 188:19281939.
  • 19
    Paranhos-Baccala G, Komurian-Pradel F, Richard N, Vernet G, Lina B, Floret D. Mixed respiratory virus infections. J Clin Virol 2008; 43:407410.
  • 20
    Semple MG, Cowell A, Dove W et al. Dual infection of infants by human metapneumovirus and human respiratory syncytial virus is strongly associated with severe bronchiolitis. J Infect Dis 2005; 191:382386.
  • 21
    Wolf DG, Greenberg D, Kalkstein D et al. Comparison of human metapneumovirus, respiratory syncytial virus and influenza A virus lower respiratory tract infections in hospitalized young children. Pediatr Infect Dis J 2006; 25:320324.
  • 22
    Walsh EE. Respiratory syncytial virus infection in adults. Sem Respir Crit Care Med 2011; 32:423432.
  • 23
    Lee N, Lui GC, Wong KT et al. High morbidity and mortality in adults hospitalized for respiratory syncytial virus infections. Clin Infect Dis 2013; 57:10691077.
  • 24
    Cane PA, van den Hoogen BG, Chakrabarti S, Fegan CD, Osterhaus AD. Human metapneumovirus in a haematopoietic stem cell transplant recipient with fatal lower respiratory tract disease. Bone Marrow Transplant 2003; 31:309310.
  • 25
    Englund JA, Boeckh M, Kuypers J et al. Brief communication: fatal human metapneumovirus infection in stem-cell transplant recipients. Ann Intern Med 2006; 144:344349.
  • 26
    Hicks LA, Shepard CW, Britz PH et al. Two outbreaks of severe respiratory disease in nursing homes associated with rhinovirus. J Am Geriatr Soc 2006; 54:284289.
  • 27
    Louie JK, Yagi S, Nelson FA et al. Rhinovirus outbreak in a long term care facility for elderly persons associated with unusually high mortality. Clin Infect Dis 2005; 41:262265.
  • 28
    Corne JM, Marshall C, Smith S et al. Frequency, severity, and duration of rhinovirus infections in asthmatic and non-asthmatic individuals: a longitudinal cohort study. Lancet 2002; 359:831834.
  • 29
    Greenberg SB, Allen M, Wilson J, Atmar RL. Respiratory viral infections in adults with and without chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2000; 162:167173.
  • 30
    Kraft CS, Jacob JT, Sears MH, Burd EM, Caliendo AM, Lyon GM. Severity of human rhinovirus infection in immunocompromised adults is similar to that of 2009 H1N1 influenza. J Clin Microbiol 2012; 50:10611063.
  • 31
    Ghosh S, Champlin R, Couch R et al. Rhinovirus infections in myelosuppressed adult blood and marrow transplant recipients. Clin Infect Dis 1999; 29:528532.
  • 32
    Ison MG, Hayden FG, Kaiser L, Corey L, Boeckh M. Rhinovirus infections in hematopoietic stem cell transplant recipients with pneumonia. Clin Infect Dis 2003; 36:11391143.
  • 33
    Debur MC, Vidal LR, Stroparo E et al. Human metapneumovirus infection in hematopoietic stem cell transplant recipients. Transpl Infect Dis 2010; 12:173179.
  • 34
    Small TN, Casson A, Malak SF et al. Respiratory syncytial virus infection following hematopoietic stem cell transplantation. Bone Marrow Transplant 2002; 29:321327.
  • 35
    Kim YJ, Boeckh M, Englund JA. Community respiratory virus infections in immunocompromised patients: hematopoietic stem cell and solid organ transplant recipients, and individuals with human immunodeficiency virus infection. Semin Respir Crit Care Med 2007; 28:222242.
  • 36
    van Elden LJ, van Kraaij MG, Nijhuis M et al. Polymerase chain reaction is more sensitive than viral culture and antigen testing for the detection of respiratory viruses in adults with hematological cancer and pneumonia. Clin Infect Dis 2002; 34:177183.
  • 37
    Gottlieb J, Schulz TF, Welte T et al. Community-acquired respiratory viral infections in lung transplant recipients: a single season cohort study. Transplantation 2009; 87:15301537.
  • 38
    Vilchez RA, McCurry K, Dauber J et al. Influenza virus infection in adult solid organ transplant recipients. Am J Transplant 2002; 2:287291.
  • 39
    Williams JV, Martino R, Rabella N et al. A prospective study comparing human metapneumovirus with other respiratory viruses in adults with hematologic malignancies and respiratory tract infections. J Infect Dis 2005; 192:10611065.
  • 40
    Ghosh S, Champlin RE, Englund J et al. Respiratory syncytial virus upper respiratory tract illnesses in adult blood and marrow transplant recipients: combination therapy with aerosolized ribavirin and intravenous immunoglobulin. Bone Marrow Transplant 2000; 25:751755.
  • 41
    Hohenthal U, Nikoskelainen J, Vainionpaa R et al. Parainfluenza virus type 3 infections in a hematology unit. Bone Marrow Transplant 2001; 27:295300.
  • 42
    Nichols WG, Gooley T, Boeckh M. Community-acquired respiratory syncytial virus and parainfluenza virus infections after hematopoietic stem cell transplantation: the Fred Hutchinson Cancer Research Center experience. Biol Blood Marrow Transplant 2001; 7(Suppl):11S15S.
  • 43
    Louie JK, Acosta M, Winter K et al. Factors associated with death or hospitalization due to pandemic 2009 influenza A(H1N1) infection in California. JAMA. 2009; 302:18961902.
  • 44
    Fuhrman C, Bonmarin I, Paty AC et al. Severe hospitalised 2009 pandemic influenza A(H1N1) cases in France, 1 July–15 November 2009 Euro Surveill 2010;15: pii: 19463.
  • 45
    O'Riordan S, Barton M, Yau Y, Read SE, Allen U, Tran D. Risk factors and outcomes among children admitted to hospital with pandemic H1N1 influenza. CMAJ. 2010; 182:3944.
  • 46
    Cocoros NM, Lash TL, Demaria A, Jr., Klompas M. Obesity as a risk factor for severe influenza-like illness. Influenza Other Respir Viruses 2014; 8:2532.
  • 47
    Dimopoulos G, Lerikou M, Tsiodras S et al. Viral epidemiology of acute exacerbations of chronic obstructive pulmonary disease. Pulm Pharmacol Ther 2012; 25:1218.
  • 48
    Walsh EE, Peterson DR, Falsey AR. Human metapneumovirus infections in adults: another piece of the puzzle. Arch Intern Med 2008; 168:24892496.
  • 49
    Widmer K, Zhu Y, Williams JV, Griffin MR, Edwards KM, Talbot HK. Rates of hospitalizations for respiratory syncytial virus, human metapneumovirus, and influenza virus in older adults. J Infect Dis 2012; 206:5662.
  • 50
    Mallia P, Message SD, Gielen V et al. Experimental rhinovirus infection as a human model of chronic obstructive pulmonary disease exacerbation. Am J Respir Crit Care Med 2011; 183:734742.
  • 51
    Doshi S, Kamimoto L, Finelli L et al. Description of antiviral treatment among adults hospitalized with influenza before and during the 2009 pandemic: United States, 2005–2009. J Infect Dis 2011; 204:18481856.
  • 52
    Harper SA, Bradley JS, Englund JA et al. Seasonal influenza in adults and children–diagnosis, treatment, chemoprophylaxis, and institutional outbreak management: clinical practice guidelines of the Infectious Diseases Society of America. Clin Infect Dis 2009; 48:10031032.
  • 53
    McGeer A, Green KA, Plevneshi A et al. Antiviral therapy and outcomes of influenza requiring hospitalization in Ontario, Canada. Clin Infect Dis 2007; 45:15681575.
  • 54
    Hanshaoworakul W, Simmerman JM, Narueponjirakul U et al. Severe human influenza infections in Thailand: oseltamivir treatment and risk factors for fatal outcome. PLoS ONE 2009; 4:e6051.
  • 55
    Louie JK, Yang S, Acosta M et al. Treatment with neuraminidase inhibitors for critically ill patients with influenza A (H1N1)pdm09. Clin Infect Dis 2012; 55:11981204.
  • 56
    Viasus D, Pano-Pardo JR, Pachon J et al. Timing of oseltamivir administration and outcomes in hospitalized adults with pandemic 2009 influenza A(H1N1) virus infection. Chest 2011; 140:10251032.
  • 57
    Higuera Iglesias AL, Kudo K, Manabe T et al. Reducing occurrence and severity of pneumonia due to pandemic H1N1 2009 by early oseltamivir administration: a retrospective study in Mexico. PLoS ONE 2011; 6:e21838.
  • 58
    Fiore AE, Fry A, Shay D et al. Antiviral agents for the treatment and chemoprophylaxis of influenza – recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 2011; 60:124.
  • 59
    Aoki FY, Macleod MD, Paggiaro P et al. Early administration of oral oseltamivir increases the benefits of influenza treatment. J Antimicrob Chemother 2003; 51:123129.
  • 60
    Lee N, Chan PK, Hui DS et al. Viral loads and duration of viral shedding in adult patients hospitalized with influenza. J Infect Dis 2009; 200:492500.
  • 61
    Centers for Disease Control. Seasonal Influenza Available from: – table. (Accessed 8 July 2013).
  • 62
    Bonner AB, Monroe KW, Talley LI, Klasner AE, Kimberlin DW. Impact of the rapid diagnosis of influenza on physician decision-making and patient management in the pediatric emergency department: results of a randomized, prospective, controlled trial. Pediatrics 2003; 112:363367.