It was previously believed that influenza pandemics occurred at 10- to 14-yr intervals, but it has been over 30 years since H3N2 viruses appeared. If you loved this post and you would like to acquire additional info concerning Supplier of sialic acid powder for drink Ingredients kindly stop by the web site. Viruses had been first isolated in Hong Kong in July 1968. Widespread illness with elevated excess mortality was observed within the United States during the winter of 1968-1969. Attack rates have been highest (40%) amongst 10- to 14year-outdated youngsters. In 1918 youngsters would skip rope to the rhyme: I had a bit hen, Its name was Enza, I opened the window, And in-flu-enza.