tetano
Editor, Senior Moderator
J Infect Dis. (2012) doi: 10.1093/infdis/jis517
Increase in Rates of Hospitalization Due to Laboratory-Confirmed Influenza Among Children and Adults During the 2009?10 Influenza Pandemic
Chad M. Cox1,
Tiffany D'Mello1,3,
Alejandro Perez1,
Arthur Reingold2,7,
Ken Gershman2,8,
Kimberly Yousey-Hindes2,9,
Kathryn E. Arnold2,4,
Monica M. Farley2,4,5,6,
Patricia Ryan2,10,
Ruth Lynfield2,11,
Craig Morin2,11,
Joan Baumbach2,12,
Emily B. Hancock2,12,
Shelley Zansky2,13,
Nancy M. Bennett2,14,
Ann Thomas2,15,
William Schaffner2,16,
Lyn Finelli1 and
for the Emerging Infections Programs Network
+ Author Affiliations
1Influenza Division
2Emerging Infections Program, Centers for Disease Control and Prevention
3Battelle
4Emerging Infections Program, Georgia Division of Public Health
5Emory University
6Atlanta VA Medical Center, Atlanta, Georgia
7California Emerging Infections Program, Oakland
8Colorado Department of Public Health and Environment, Denver
9Connecticut Emerging Infections Program, Yale University School of Public Health, New Haven
10Maryland Department of Health and Mental Hygiene, Baltimore
11Minnesota Department of Health, St. Paul
12New Mexico Department of Health, Santa Fe
13Emerging Infections Program, New York State Department of Health, Albany
14Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
15Oregon Public Health Division, Portland
16Department of Preventive Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
Correspondence: Lyn Finelli, DrPH, MS, Influenza Division, Centers for Disease Control and Prevention, 1600 Clifton Rd NE, MS A-32, Atlanta, GA 30333 (lyf8@cdc.gov).
Abstract
Background. The Emerging Infections Programs (EIP) network has conducted population-based surveillance for hospitalizations due to laboratory-confirmed influenza among children since 2003, with the network expanding in 2005 to include adults.
Methods. From 15 April 2009 through 30 April 2010, the EIP conducted surveillance among 22.1 million people residing in 10 states. Incidence rates per 100 000 population were calculated using US Census Bureau data. Mean historic rates were calculated on the basis of previously published and unpublished EIP data.
Results. During the 2009 pandemic of influenza A virus subtype H1N1 infection, rates of hospitalizations due to laboratory-confirmed influenza were 202, 88, 49, 31, 27, 36, 28, and 27 episodes per 100 000 among persons aged <6 months, 6?23 months, 2?4 years, 5?17 years, 18?49 years, 50?64 years, 65?74 years, and ≥75 years, respectively. Comparative mean rates from previous influenza seasons during which EIP conducted surveillance were 153, 53, 20, 6, 4, 8, 20, and 56 episodes per 100 000 among persons aged <6 months, 6?23 months, 2?4 years, 5?17 years, 18?49 years, 50?64 years, 65?74 years, and ≥75 years, respectively.
Conclusions. During the pandemic, rates of hospitalization due to laboratory-confirmed influenza among individuals aged 5?17 years and 18?49 years increased 5-fold and 6-fold, respectively, compared with mean rates from previous influenza seasons. Hospitalization rates for other pediatric and adult age groups increased, compared with mean rates from previous influenza seasons, whereas the rate among individuals aged ≥75 years decreased.
Increase in Rates of Hospitalization Due to Laboratory-Confirmed Influenza Among Children and Adults During the 2009?10 Influenza Pandemic
Chad M. Cox1,
Tiffany D'Mello1,3,
Alejandro Perez1,
Arthur Reingold2,7,
Ken Gershman2,8,
Kimberly Yousey-Hindes2,9,
Kathryn E. Arnold2,4,
Monica M. Farley2,4,5,6,
Patricia Ryan2,10,
Ruth Lynfield2,11,
Craig Morin2,11,
Joan Baumbach2,12,
Emily B. Hancock2,12,
Shelley Zansky2,13,
Nancy M. Bennett2,14,
Ann Thomas2,15,
William Schaffner2,16,
Lyn Finelli1 and
for the Emerging Infections Programs Network
+ Author Affiliations
1Influenza Division
2Emerging Infections Program, Centers for Disease Control and Prevention
3Battelle
4Emerging Infections Program, Georgia Division of Public Health
5Emory University
6Atlanta VA Medical Center, Atlanta, Georgia
7California Emerging Infections Program, Oakland
8Colorado Department of Public Health and Environment, Denver
9Connecticut Emerging Infections Program, Yale University School of Public Health, New Haven
10Maryland Department of Health and Mental Hygiene, Baltimore
11Minnesota Department of Health, St. Paul
12New Mexico Department of Health, Santa Fe
13Emerging Infections Program, New York State Department of Health, Albany
14Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
15Oregon Public Health Division, Portland
16Department of Preventive Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
Correspondence: Lyn Finelli, DrPH, MS, Influenza Division, Centers for Disease Control and Prevention, 1600 Clifton Rd NE, MS A-32, Atlanta, GA 30333 (lyf8@cdc.gov).
Abstract
Background. The Emerging Infections Programs (EIP) network has conducted population-based surveillance for hospitalizations due to laboratory-confirmed influenza among children since 2003, with the network expanding in 2005 to include adults.
Methods. From 15 April 2009 through 30 April 2010, the EIP conducted surveillance among 22.1 million people residing in 10 states. Incidence rates per 100 000 population were calculated using US Census Bureau data. Mean historic rates were calculated on the basis of previously published and unpublished EIP data.
Results. During the 2009 pandemic of influenza A virus subtype H1N1 infection, rates of hospitalizations due to laboratory-confirmed influenza were 202, 88, 49, 31, 27, 36, 28, and 27 episodes per 100 000 among persons aged <6 months, 6?23 months, 2?4 years, 5?17 years, 18?49 years, 50?64 years, 65?74 years, and ≥75 years, respectively. Comparative mean rates from previous influenza seasons during which EIP conducted surveillance were 153, 53, 20, 6, 4, 8, 20, and 56 episodes per 100 000 among persons aged <6 months, 6?23 months, 2?4 years, 5?17 years, 18?49 years, 50?64 years, 65?74 years, and ≥75 years, respectively.
Conclusions. During the pandemic, rates of hospitalization due to laboratory-confirmed influenza among individuals aged 5?17 years and 18?49 years increased 5-fold and 6-fold, respectively, compared with mean rates from previous influenza seasons. Hospitalization rates for other pediatric and adult age groups increased, compared with mean rates from previous influenza seasons, whereas the rate among individuals aged ≥75 years decreased.