“The seasonal vaccine is not designed to protect against H3N2v. Limited studies show that it may boost immunity against this virus in adults, but will probably not offer protection for children.”-U.S. Centers for Disease Control and Prevention

The U.S. CDC is concerned after 12 people caught H3N2v (the ‘v’ stands for “variant”) between August and December 2011.

“This virus is related to human flu viruses from the 1990s, so adults should have some immunity, but young children probably do not. Early steps to make a vaccine against H3N2v have been taken, but no decision to mass produce such a vaccine has been made. Public health authorities are watching closely.”-U.S. CDC