%0 Journal Article
%T Pandemic 2009 H1N1 virus infection in children and adults: A cohort study at a single hospital throughout the epidemic
%A Jung-Woo Rhim
%A Eun-Ji Go
%A Kyung-Yil Lee
%A You-Sook Youn
%A Myung-Sook Kim
%A Sun Hee Park
%A Ji-Chang Kim
%A Jin-Han Kang
%J International Archives of Medicine
%D 2012
%I BioMed Central
%R 10.1186/1755-7682-5-13
%X We evaluated the epidemiologic characteristics of patients infected with the 2009 H1N1 influenza A virus (4,463 patients, age range from 2 mo to 86 y), and the clinical and laboratory findings of 373 inpatients (80/217 children, ¡Ü 15 y, had pneumonia and 36/156 adults, > 16 y, had pneumonia) in a single hospital during the epidemic.The majority of infected patients (94%) were less than 40 y, and greater than 90% of cases occurred during a two-month period. The rates of admission and pneumonia were 8.4% (373/4,463) and 2.5% (116/4,463), respectively. The rates of admission and pneumonia, total duration of fever, the frequency of underlying diseases, and the values of C-reactive protein and erythrocyte sedimentation rate tended to increase as age increased; highest rates were found in the ¡Ý 65 y group. Pneumonia was founded more boys than girls in children, but more female than male in adults. The adult patients with pneumonia had higher leukocyte counts with lower lymphocyte differentials than the group without pneumonia, as shown in children group.Our results suggest that the immunologic reaction to viral insults may be associated with age, sex and underlying diseases, and that unknown herd immunity may affect populations. The patients with underlying diseases, especially in older patients may have immunologic insufficiency that is associated with immunologic consumption by the underlying diseases.Since the 2009 H1N1 influenza A virus was first isolated in North America in spring 2009, there was an influenza pandemic in South Korea in 2009 as well as in other countries. Although the mortality of the 2009 H1N1 influenza A virus pandemic (2009 H1N1 flu) has been reported to be not exceed that of seasonal (inter-pandemic) influenza, some epidemiological characteristics of the pandemic, including its age distribution, differ from those of seasonal influenza [1,2]. In seasonal influenza, young infants and older persons are vulnerable and the mortality rate is higher in t
%K H1N1 influenza virus
%K Epidemiology
%K Pneumonia
%K Children
%K Adults
%U http://www.intarchmed.com/content/5/1/13