Severity of Influenza A(H1N1) Illness and Emergence of D225G Variant, 2013–14 Influenza Season, Florida, USA - Volume 21, Number 4—April 2015 - Emerging Infectious Disease journal - CDC
Volume 21, Number 4—April 2015
Severity of Influenza A(H1N1) Illness and Emergence of D225G Variant, 2013–14 Influenza Season, Florida, USA
In 2009, a novel influenza virus, influenza A(H1N1)pdm09, emerged. The resulting pandemic disproportionately affected persons <65 years of age (1), but illness caused by the virus was similar in severity to that caused by seasonal influenza (2). As the 2013–14 influenza season progressed, physicians at a Florida hospital noted that patients <65 years of age were affected in numbers similar to those seen in 2009–10, but with increased severity. To investigate these observations, we obtained the number of influenza admissions during the 2013–14 season, characterized pathologic findings in deceased patients, sequenced subtype H1N1 viruses, and assessed receptor-specific characteristics.
Dr. Iovine is the hospital epidemiologist at the University of Florida Health in Gainesville, Florida. Her research interests include the epidemiology of novel respiratory viruses and innate defense against multidrug-resistant gram-negative organisms.
We thank Gregory Gray and Gary Heil for useful discussions regarding this work.
This work was supported by the University of Florida Emerging Pathogens Institute and UF Health.
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Suggested citation for this article: Iovine NM, Morris JG Jr, Fredenburg K, Rand K, Alnuaimat H, Lipori G, et al. Increased severity of influenza A(H1N1) virus infection during the 2013–14 influenza season, Florida, USA. Emerg Infect Dis. 2015 Apr [date cited]. http://dx.doi.org/10.3201/eid2104.141375