Increase in Influenza A H3N2v Virus Infections CDC HEALTH ADVISORY
Multiple infections with variant* influenza A (H3N2v) viruses
have been identified in 3 states and has been isolated in
U.S. swine. While the viruses identified in these cases are
genetically nearly identical, separate swine exposure events in
different states were associated with human infections. There is
no indication that the cases in different states are
More than half of the recent infections with H3N2v have occurred
after contact with pigs, but in some cases, the virus seems to
have spread from person-to-person. So far spread has not
continued beyond one or two people.
Clinical characteristics of the 16 H3N2v recent cases have been
generally consistent with signs and symptoms of seasonal
influenza, and have included fever, cough, pharyngitis, myalgia,
and headache. No hospitalizations or deaths have occurred among
the 16 confirmed cases since July 2012.