CDC: Older kids more at H1N1 risk

VANCOUVER, British Columbia, May 5 (UPI) -- Older children, especially those with underlying medical conditions, are more at risk of H1N1 influenza than seasonal flu, U.S. researchers said.

"Our findings underscore the importance of influenza immunization in children of all ages and particularly in children with underlying medical conditions," lead author Dr. Fatimah Dawood of the Centers for Disease Control and Prevention in Atlanta said in a statement.

"Ensuring immunization of children at risk for hospitalization with influenza will remain critical during the upcoming 2010-2011 influenza season when the 2009 pandemic H1N1 virus may continue to circulate and other seasonal influenza viruses may circulate as well."

Dawood and colleagues looked at data for 5.3 million children age 18 and younger in 10 states hospitalized with laboratory-confirmed influenza during the 2003-2009 influenza seasons or in the early 2009 H1N1 pandemic.

The researchers found those with H1N1 influenza had a median age of 5 years -- versus age 1 for those with 2003-2009 seasonal flu. The H1N1 group also had a larger proportion of those born prematurely or having pre-existing conditions such as asthma or sickle-cell disease. However, one-third of children hospitalized with H1N1 flu had previously been healthy.

The findings were presented in Vancouver at the annual meeting of Pediatric Academic Societies.