tetano
Editor, Senior Moderator
Citation: Reed C, Katz JM, Hancock K, Balish A, Fry AM, et al. (2012) Prevalence of Seropositivity to Pandemic Influenza A/H1N1 Virus in the United States following the 2009 Pandemic. PLoS ONE 7(10): e48187. doi:10.1371/journal.pone.0048187
Carrie Reed*, Jacqueline M. Katz, Kathy Hancock, Amanda Balish, Alicia M. Fry*, for the H1N1 Serosurvey Working Group?
Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
Abstract Top
Background
2009 pandemic influenza A/H1N1 (A(H1N1)pdm09) was first detected in the United States in April 2009 and resulted in a global pandemic. We conducted a serologic survey to estimate the cumulative incidence of A(H1N1)pdm09 through the end of 2009 when pandemic activity had waned in the United States.
Methods
We conducted a pair of cross sectional serologic surveys before and after the spring/fall waves of the pandemic for evidence of seropositivity (titer ≥40) using the hemagglutination inhibition (HI) assay. We tested a baseline sample of 1,142 serum specimens from the 2007?2008 National Health and Nutrition Examination Survey (NHANES), and 2,759 serum specimens submitted for routine screening to clinical diagnostic laboratories from ten representative sites.
Results
The age-adjusted prevalence of seropositivity to A(H1N1)pdm09 by year-end 2009 was 36.9% (95%CI: 31.7?42.2%). After adjusting for baseline cross-reactive antibody, pandemic vaccination coverage and the sensitivity/specificity of the HI assay, we estimate that 20.2% (95%CI: 10.1?28.3%) of the population was infected with A(H1N1)pdm09 by December 2009, including 53.3% (95%CI: 39.0?67.1%) of children aged 5?17 years.
Conclusions
By December 2009, approximately one-fifth of the US population, or 61.9 million persons, may have been infected with A(H1N1)pdm09, including around half of school-aged children
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0048187
Carrie Reed*, Jacqueline M. Katz, Kathy Hancock, Amanda Balish, Alicia M. Fry*, for the H1N1 Serosurvey Working Group?
Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
Abstract Top
Background
2009 pandemic influenza A/H1N1 (A(H1N1)pdm09) was first detected in the United States in April 2009 and resulted in a global pandemic. We conducted a serologic survey to estimate the cumulative incidence of A(H1N1)pdm09 through the end of 2009 when pandemic activity had waned in the United States.
Methods
We conducted a pair of cross sectional serologic surveys before and after the spring/fall waves of the pandemic for evidence of seropositivity (titer ≥40) using the hemagglutination inhibition (HI) assay. We tested a baseline sample of 1,142 serum specimens from the 2007?2008 National Health and Nutrition Examination Survey (NHANES), and 2,759 serum specimens submitted for routine screening to clinical diagnostic laboratories from ten representative sites.
Results
The age-adjusted prevalence of seropositivity to A(H1N1)pdm09 by year-end 2009 was 36.9% (95%CI: 31.7?42.2%). After adjusting for baseline cross-reactive antibody, pandemic vaccination coverage and the sensitivity/specificity of the HI assay, we estimate that 20.2% (95%CI: 10.1?28.3%) of the population was infected with A(H1N1)pdm09 by December 2009, including 53.3% (95%CI: 39.0?67.1%) of children aged 5?17 years.
Conclusions
By December 2009, approximately one-fifth of the US population, or 61.9 million persons, may have been infected with A(H1N1)pdm09, including around half of school-aged children
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0048187