LONDON, Dec. 17, 2012 /PRNewswire/ -- GlaxoSmithKline plc [LSE/NYSE: GSK] announced today that the U.S. Food and Drug Administration (FDA) has approved FLUARIX® QUADRIVALENT (Influenza Virus Vaccine) for the immunisation of children (three years and older) and adults to help prevent disease caused by seasonal influenza (flu) virus subtypes A and type B contained in the vaccine. Fluarix Quadrivalent is the first intramuscular vaccine to cover against four influenza strains. Scientists classify the influenza strains that cause seasonal flu as A or B strains. Currently administered trivalent (three-strain) flu vaccines help protect against the two A virus strains most common in humans and the B strain expected to be predominant in a given year. But since the year 2000, two B virus strains ( Victoria and Yamagata) have co-circulated to varying degrees each season. Various degrees of mismatch have occurred between the B strain included in trivalent vaccines and the B strain that actually circulated, causing an increased risk of influenza-related morbidity across all age groups – children, adults and the elderly. Fluarix Quadrivalent helps protect against the two A strains and adds coverage against a second B strain. "Trivalent influenza vaccines have helped protect millions of people against flu, but in six of the last 11 flu seasons, the predominant circulating influenza B strain was not the strain that public health authorities selected," said Dr. Leonard Friedland, V.P. and Head, GSK North America Vaccines Clinical Development and Medical Affairs. "Fluarix Quadrivalent will help protect individuals against both B strains and from a public-health standpoint, can help decrease the burden of disease." GSK will make Fluarix Quadrivalent available in time for the 2013-14 flu season and and also plans to fulfill orders for its trivalent vaccines. Healthcare providers traditionally order flu vaccines about a year in advance of each flu season.