• 1
    Centers for Disease Control and Prevention. Outbreak of swine-origin influenza A (H1N1) virus infection - Mexico, March-April 2009. MMWR Morb Mortal Wkly Rep. 2009; 58:46770.
  • 2
    Anonymous. New influenza A (H1N1) virus: WHO guidance on public health measures, 11 June 2009. Wkly Epidemiol Rec. 2009;84:2614.
  • 3
    World Health Organization. Pandemic (H1N1) 2009 - Update 98. Available at: Accessed Oct 17, 2012.
  • 4
    Kim WJ. Pandemic influenza (H1N1 2009): experience and lessons. Infect Chemother. 2010; 42:613.
  • 5
    Glezen WP, Decker M, Perrotta DM. Survey of underlying conditions of persons hospitalized with acute respiratory disease during influenza epidemics in Houston, 1978–1981. Am Rev Respir Dis. 1987; 136:5505.
  • 6
    Izurieta HS, Thompson WW, Kramarz P, et al. Influenza and the rates of hospitalization for respiratory disease among infants and young children. N Engl J Med. 2000; 342:2329.
  • 7
    Novel Swine-Origin Influenza A (H1N1) Virus Investigation Team, Dawood FS, Jain S, et al. Emergence of a novel swine-origin influenza A (H1N1) virus in humans. N Engl J Med. 2009;360:260515.
  • 8
    Perez-Padilla R, de la Rosa-Zamboni D, Ponce de Leon S, et al. Pneumonia and respiratory failure from swine-origin influenza A (H1N1) in Mexico. N Engl J Med. 2009;361:6809.
  • 9
    World Health Organization. CDC Protocol of Realtime RTPCR for Influenza A (H1N1). Available at: Accessed Oct 17, 2012.
  • 10
    Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis. 2007; 44(Suppl 2):S2772.
  • 11
    Yealy DM, Auble TE, Fine MJ. Using the pneumonia severity index to guide hospitalization decisions. Am J Med. 2007; 120:e21.
  • 12
    Rothberg MB, Haessler SD. Complications of seasonal and pandemic influenza. Crit Care Med. 2010; 38(4 Suppl):e917.
  • 13
    Jain S, Kamimoto L, Bramley AM, et al. Hospitalized patients with 2009 H1N1 influenza in the United States, April-June 2009. N Engl J Med. 2009; 361:193544.
  • 14
    Chowell G, Bertozzi SM, Colchero MA, et al. Severe respiratory disease concurrent with the circulation of H1N1 influenza. N Engl J Med. 2009; 361:6749.
  • 15
    Morris AE, Stapleton RD, Rubenfeld GD, Hudson LD, Caldwell E, Steinberg KP. The association between body mass index and clinical outcomes in acute lung injury. Chest. 2007; 131:3428.
  • 16
    Centers for Disease Control and Prevention. Intensive-care patients with severe novel influenza A (H1N1) virus infection - Michigan, June 2009. MMWR Morb Mortal Wkly Rep. 2009; 58:74952.
  • 17
    Kumar A, Zarychanski R, Pinto R, et al. Critically ill patients with 2009 influenza A (H1N1) infection in Canada. JAMA. 2009; 302:18729.
  • 18
    Cao B, Li XW, Mao Y, et al. Clinical features of the initial cases of 2009 pandemic influenza A (H1N1) virus infection in China. N Engl J Med. 2009; 361:250717.
  • 19
    Angeles Marcos M, Camps M, Pumarola T, et al. The role of viruses in the aetiology of community-acquired pneumonia in adults. Antivir Ther. 2006;11:3519.
  • 20
    Hietala J, Uhari M, Tuokko H, Leinonen M. Mixed bacterial and viral infections are common in children. Pediatr Infect Dis J. 1989; 8:6836.
  • 21
    McCarthy PL, Frank AL, Ablow RC, Masters SJ, Dolan TF. Value of the C-reactive protein test in the differentiation of bacterial and viral pneumonia. J Pediatr. 1978; 92:4546.
  • 22
    Simon L, Gauvin F, Amre DK, Saint-Louis P, Lacroix J. Serum procalcitonin and C-reactive protein levels as markers of bacterial infection: a systematic review and meta-analysis. Clin Infect Dis. 2004; 39:20617.
  • 23
    Moulin F, Raymond J, Lorrot M, et al. Procalcitonin in children admitted to hospital with community acquired pneumonia. Arch Dis Child. 2001; 84:3326.
  • 24
    Ingram PR, Inglis T, Moxon D, Speers D. Procalcitonin and C-reactive protein in severe 2009 H1N1 influenza infection. Intensive Care Med. 2010; 36:52832.
  • 25
    Ho YC, Wang JL, Wang JT, et al. Prognostic factors for fatal adult influenza pneumonia. J Infect. 2009; 58:43945.
  • 26
    Choi WJ, Kim WY, Kim SH, et al. Clinical characteristics of pneumonia in hospitalized patients with novel influenza A (H1N1) in Korea. Scand J Infect Dis. 2010; 42:3114.
  • 27
    Ajlan AM, Quiney B, Nicolaou S, Muller NL. Swine-origin influenza A (H1N1) viral infection: radiographic and CT findings. AJR Am J Roentgenol. 2009; 193:14949.
  • 28
    Dominguez-Cherit G, Lapinsky SE, Macias AE, et al. Critically ill patients with 2009 influenza A (H1N1) in Mexico. JAMA. 2009; 302:18807.
  • 29
    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; 302:1896902.
  • 30
    Centers for Disease Control and Prevention. Bacterial coinfections in lung tissue specimens from fatal cases of 2009 pandemic influenza A (H1N1) - United States, May-August 2009. MMWR Morb Mortal Wkly Rep. 2009; 58:10714.
  • 31
    Commons RJ, Denholm J. Triaging pandemic flu: pneumonia severity scores are not the answer. Int J Tuberc Lung Dis. 2012; 16:6703.