Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-13T00:45:34.540Z Has data issue: false hasContentIssue false
  • English
  • Français

Differences in the Epidemiological Characteristics and Clinical Outcomes of Pandemic (H1N1) 2009 Influenza, Compared with Seasonal Influenza

Published online by Cambridge University Press:  02 January 2015

Kevin T. Shiley ,
Gregory Nadolski ,
Timothy Mickus ,
Neil O. Fishman  and
Ebbing Lautenbach
Kevin T. Shiley*
Affiliation:
Division of Infectious Diseases, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
Gregory Nadolski
Affiliation:
Department of Radiology, University of Pennsylvania School of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
Timothy Mickus
Affiliation:
Department of Radiology, University of Pennsylvania School of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
Neil O. Fishman
Affiliation:
Division of Infectious Diseases, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
Ebbing Lautenbach
Affiliation:
Division of Infectious Diseases, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania Department of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania Center for Education and Research on Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
*
3rd Floor, Suite D, 3400 Spruce Street, Philadelphia, PA 19103 (shileyk@uphs.upenn.edu)
Get access Rights & Permissions [Opens in a new window]

Extract

Background.

There are limited data comparing the clinical presentations, comorbidities, and outcomes of patients with infections due to seasonal influenza with patients with infections due to pandemic (H1N1) 2009 influenza.

Objective.

To compare the epidemiological characteristics and outcomes of pandemic (H1N1) 2009 influenza with those of seasonal influenza.

Methods.

A cross-sectional study was conducted among patients who received diagnoses during emergency department and inpatient encounters at 2 affiliated academic medical centers in Philadelphia, Pennsylvania. Cases of seasonal influenza during the period November 1, 2005, through June 1, 2008, and cases of pandemic influenza during the period from May 1, 2009, through August 7, 2009, were identified retrospectively.

Results.

Forty-nine cases of pandemic influenza and 503 cases of seasonal influenza were identified. Patients with pandemic H1N1 were younger (median age, 29 years) than patients with seasonal influenza (median age, 59 years) (P <.001). More patients with pandemic H1N1 (35 [71%] of 49) were African American, compared with patients with seasonal influenza (267 [53%] of 503; P = .02). Several symptoms were more common among patients with pandemic influenza infections than among patients with seasonal influenza infections: cough (98% vs 83%; P = .007), myalgias (71% vs 46%; P = .001), and pleuritic chest pain (45% vs 15%; P < .001). Pregnancy was the only comorbidity that occurred significantly more often in the pandemic influenza group than in the seasonal influenza group (16% vs 1%; P < .001). There were no significant differences in frequencies of deaths of hospitalized patients, intensive care unit admission, or length of hospitalization between groups.

Conclusion.

Other than pregnancy, there were few clinically important differences between infections due to seasonal influenza and those due to pandemic influenza. The greater rate of lower respiratory tract symptoms in pandemic cases might serve to differentiate pandemic influenza from seasonal influenza.

Type
Original Articles
Information
Infection Control & Hospital Epidemiology , Volume 31 , Issue 7 , July 2010 , pp. 676 - 682
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Chen, M. World now at the start of 2009 influenza pandemic. World Health Organization Web site, http://www.who.int/mediacentre/news/statements/2009/h1n1_pandemic_phase6_20090611/en/index.html. Published 2009. Accessed September 24, 2009.Google Scholar
2.Chowell, G, Bertozzi, SM, Colchero, MA, et al. Severe respiratory disease concurrent with the circulation of H1N1 influenza. N Engl J Med 2009; 361(7):674–679.CrossRefGoogle ScholarPubMed
3.Centers for Disease Control and Prevention. Surveillance for pediatric deaths associated with 2009 pandemic influenza A (H1N1) virus infection—United States, April-August 2009. MMWR Morb Mortal Wkly Rep 2009;58(34): 941–947.Google Scholar
4.Nishiura, H, Castillo-Chavez, C, Safan, M, Chowell, G. Transmission potential of the new influenza A (H1N1) virus and its age-specificity in Japan. Euro Surveill 2009;14(22): pii = 19227. http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId = 19227. Published June 4, 2009. Accessed September 23, 2009.CrossRefGoogle ScholarPubMed
5.Centers for Disease Control and Prevention. 2009 pandemic influenza A (H1N1) virus infections—Chicago, Illinois, April-July 2009. MMWR Morb Mortal Wkly Rep 2009;58(33): 913–918.Google Scholar
6.Gilsdorf, A, Poggensee, G. Influenza A(H1N1)v in Germany: the first 10,000 cases. Euro Surveill 2009;14(34): pii= 19318. http://www.euro surveillance.org/ViewArticle.aspx?ArticleId= 19318. Published August 27, 2009. Accessed September 23, 2009.CrossRefGoogle Scholar
7. 2009 H1N1 flu situation update. Centers for Disease Control and Prevention Web site, http://www.cdc.gov/hlnlflu/update.htm. Published September 25, 2009. Accessed September 25, 2009.Google Scholar
8. Pandemic (H1N1) 2009—update 67. World Health Organization Web site, http://www.who.int/csr/don/2009_09_25/en/index.html. Published September 25, 2009. Accessed September 25, 2009.Google Scholar
9.Kelly, HA, Grant, KA, Williams, S, Fielding, J, Smith, D. Epidemiological characteristics of pandemic influenza H1N1 2009 and seasonal influenza infection. Med J Aust 2009;191(3): 146–149.CrossRefGoogle ScholarPubMed
10.Chang, YS, van Hal, SJ, Spencer, PM, Gosbell, IB, Collett, PW. Comparison of adult patients hospitalised with pandemic (H1N1) 2009 influenza and seasonal influenza during the “PROTECT” phase of the pandemic response. Med J Aust 2010;192(2): 90–93.CrossRefGoogle ScholarPubMed
11.Gordon, A, Saborio, S, Videa, E, et al. Clinical attack rate and presentation of pandemic H1N1 influenza versus seasonal influenza A and B in a pediatric cohort in Nicaragua. Clin Infect Dis 2010;50(11): 1462–1467.CrossRefGoogle Scholar
12.Surveillance for the 2009 pandemic influenza A (H1N1) virus and seasonal influenza viruses—New Zealand, 2009. MMWR Morb Mortal Wkly Rep 2009;58(33): 918–921.Google Scholar
13.Vaillant, L, La Ruche, G, Tarantola, A, Barboza, P. Epidemiology of fatal cases associated with pandemic H1N1 influenza 2009. Euro Surveill 2009;14(33): pii = 19309. http://www.eurosurveillance.org/ViewArticle.aspx'Articleld = 19309. Published August 20, 2009. Accessed September 25, 2009.CrossRefGoogle ScholarPubMed
14.Relio, J, Rodriguez, A, Ibanez, P, et al. Intensive care adult patients with severe respiratory failure caused by influenza A (H1N1)v in Spain. Crit Care 2009;13(5): R148.Google Scholar
15.James, J. Novel influenza A virus H1N1 and revised specimen submission guidelines in Pennsylvania. Pennsylvania Department of Health Web site, http://www.hlnlinpa.com/info-for-specific-groups/information-for-healthcare-providers/health-advisories-and-alerts/advisory-5/. Published June 12, 2009. Accessed May 12, 2010.Google Scholar
16.Gill, J, Sheng, Z, Ely, S, et al. Pulmonary pathological findings of fatal 2009 pandemic influenza A/H1N1 viral infections. Arch Pathol Lab Med 2010;134(2): 235–243.CrossRefGoogle ScholarPubMed
17.Finland, M, Peterson, OL, Straus, E. Staphylococcic pneumonia occurring during an epidemic of pneumonia. Arch Intern Med 1942;70(2): 183–205.CrossRefGoogle Scholar
18.Podewils, LJ, Liedtke, LA, McDonald, LC, et al. A national survey of severe influenza-associated complications among children and adults, 20032004. Clin Infect Dis 2005;40(11): 1693–1696.CrossRefGoogle ScholarPubMed
19.Oliveira, EC, Marik, PE, Colice, G. Influenza pneumonia: a descriptive study. Chest 2001;119(6): 1717–1723.CrossRefGoogle ScholarPubMed
20.Martin, C, Kunin, C, Gottlieb, L, Finland, M. Asian influenza A in Boston, 1957-1958. Arch Intern Med 1959;103:36–46.Google ScholarPubMed
21.O'Brien, KL, Walters, MI, Sellman, J, et al. Severe pneumococcal pneumonia in previously healthy children: the role of preceding influenza infection. Clin Infect Dis 2000;30(5): 784–789.CrossRefGoogle ScholarPubMed
22.Schwarzmann, SW, Adler, JL, Sullivan, RJ Jr, Marine, WM. Bacterial pneumonia during the Hong Kong influenza epidemic of 1968-1969. Arch Intern Med 1971;127(6): 1037–1041.CrossRefGoogle Scholar
23.Morens, DM, Taubenberger, JK, Fauci, AS. Predominant role of bacterial pneumonia as a cause of death in pandemic influenza: implications for pandemic influenza preparedness. J Infect Dis 2008;198(7): 962–970.CrossRefGoogle ScholarPubMed
24. 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(38): 1071–1074.Google Scholar
25.Shiley, K, Gasink, L. Antibiotic use after the diagnosis of viral respiratory tract infection in hospitalized adults. In: Infectious Diseases Society of America 47th Annual Meeting. Philadelphia, Pennsylvania; 2009. Abstract 600.Google Scholar
26.Falsey, AR, Murata, Y, Walsh, EE. Impact of rapid diagnosis on management of adults hospitalized with influenza. Arch Intern Med 2007;167(4): 354–360.Google ScholarPubMed
27.Winchester, CC, Macfarlane, T, Thomas, M, Price, D. Antibiotic prescribing and outcomes of lower respiratory tract infection in UK primary care. Chest 2009;135(5): 1163–1172.CrossRefGoogle ScholarPubMed
28.Tapson, VF. Acute pulmonary embolism. N Engl J Med 2008;358(10): 1037–1052.CrossRefGoogle ScholarPubMed
29. ACC/AHA 2007 Guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction). Circulation 2007;116(7): 803–877.CrossRefGoogle Scholar
30.Safrin, S, Rush, JD, Mills, J. Influenza in patients with human immunodeficiency virus infection. Chest 1990;98(1):33–37.CrossRefGoogle ScholarPubMed
31.Fujita, J, Bandoh, S, Yamaguchi, M, Higa, F, Tateyama, M. Chest CT findings of influenza virus-associated pneumonia in 12 adult patients. Influenza Other Respi Viruses 2007;1(5-6):183–187.CrossRefGoogle ScholarPubMed
32.Shiley, KT, Van Deerlin, V, Miller, WTJ. Chest CT features of community-acquired respiratory viral infections in adult inpatients with lower respiratory tract infections. J Thorac Imaging 2010;25(1):68–75.CrossRefGoogle ScholarPubMed
33.Jamieson, DJ, Honein, MA, Rasmussen, SA, et al. H1N1 2009 influenza virus infection during pregnancy in the USA. Lancet 2009;374(9688): 451–458.CrossRefGoogle ScholarPubMed
34.Freeman, DW, Barno, A. Deaths from Asian influenza associated with pregnancy. Am J Obstet Gynecol 1959;78:1172–1175.CrossRefGoogle ScholarPubMed
35.Neuzil, KM, Reed, GW, Mitchel, EF, Simonsen, L, Griffin, MR. Impact of influenza on acute cardiopulmonary hospitalizations in pregnant women. Am J Epidemiol 1998;148(11): 1094–1102.CrossRefGoogle ScholarPubMed
36.Harris, JW. Influenza occurring in pregnant women. JAMA 1919;72(14): 978–980.CrossRefGoogle Scholar
37.Dodds, L, McNeil, SA, Fell, DB, eta 1. Impact of influenza exposure on rates of hospital admissions and physician visits because of respiratory illness among pregnant women. CMAJ 2007; 176(4) :463–468.CrossRefGoogle ScholarPubMed
38.Fiore, AE, Shay, DK, Broder, K, et al. Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009. MMWR Recomm Rep 2009;58(RR-8):1–52.Google ScholarPubMed
39.Black, SB, Shinefield, HR, France, EK, Fireman, BH, Piatt, ST, Shay, D. Effectiveness of influenza vaccine during pregnancy in preventing hospitalizations and outpatient visits for respiratory illness in pregnant women and their infants. Am J Perinatol 2004;21(6): 333–339.CrossRefGoogle ScholarPubMed
40.Munoz, FM, Greisinger, AJ, Wehmanen, OA, et al. Safety of influenza vaccination during pregnancy. Am J Obstet Gynecol 2005;192(4): 1098–1106.CrossRefGoogle ScholarPubMed
41. Self-reported influenza vaccination coverage trends 1989-2008 among adults by age group, risk group, race/ethnicity, health-care worker status, and pregnancy status, United States, National Health Interview Survey (NHIS) [table]. Centers for Disease Control and Prevention Web site. http://www.cdc.gov/FLU/PROFESSIONALS/VACCINATION/pdf/NHIS89_08fluvaxtrendtab.pdf. Published August 18, 2008. Accessed September 25, 2009.Google Scholar