An unusual strain of swine flu, H3N3, containing a gene from the H1N1 virus that caused the 2009 global pandemic, as of October 21, 2011 had infected five young children in Pennsylvania and Indiana, USA, after four were exposed to livestock pigs at an agricultural fair, and one had contact with a person exposed to the pigs.

http://www.southbendtribune.com/news/sbt-new-swine-flu-virus-sickens-5-children-in-3-states-
20111021,0,3133475.story
http://www.chicagotribune.com/news/chi-ap-me-flustrain,0,5083072.story