Trivalent influenza vaccine for the 2010-2011 season
March 10, 2010 — JesseThe selection of viruses for seasonal flu vaccines is based on which influenza viruses circulate during the previous season. Sample viruses are collected by 130 national influenza centers in 101 countries and data on disease … Even though the 2009 H1N1 strain has not undergone significant antigenic changes, it’s important to be immunized again in anticipation of the next influenza season
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Trivalent influenza vaccine for the 2010-2011 season