Retraction. Triple reassortant swine influenza A (H3N2) virus in waterfowl.

To the Editor: We would like to retract the letter entitled “Triple Reassortant Swine Influenza A (H3N2) Virus in Waterfowl,” which was published the April 2010 issue of Emerging Infectious Diseases (). The nucleoprotein gene sequences from the viruses reported in that letter are very closely related to those from the earliest detected triple reassortant swine influenza viruses [CY095676 A/sw/Texas/4199–2/1998(H3N2)]. Although these viruses could have acquired a swine-origin segment, the branch lengths are quite short for 9 years of evolution. Therefore, we have withdrawn these 4 isolates from GenBank and subsequently retract this letter.