The face of equine influenza is evolving, and so must our understanding of its behavior and the vaccines that protect against it. Updating flu vaccines, transmission of flu between horses and dogs, and flu mutation were featured topics in a recent Equine Influenza Workshop held Nov. 3-6 in Miami, Fla. An international group of scientists, vaccine manufacturers, and government officials chaired by Jenny Mumford, PhD, director of science at the U.K.’s Animal Health Trust in Newmarket, shared research notes and discussed handling flu as it changes.


Antigenic map of human influenza A (H3N2) virus strains from 1968 to 2003. The relative position of strains (colored shapes) and antisera (uncolored open shapes) show how the strains have changed over time; the letters refer to the isolation location (HK=Hong Kong, etc.). This model could help scientists stay one step ahead of the next influenza strain to emerge and mutate, and it could eventually be adapted to predict equine influenza strains.

Tom Chambers, PhD, heads an international influenza reference lab at the University of Kentucky’s Gluck Equine Research Center. He said that in 2004, the Expert Surveillance Panel (a group of leading equine flu researchers from the Office International des Epizooties and World Health Organization, WHO) recommended an update in the strains to be used in equine vaccines—the first recommended update since 1995 ( The Panel reviewed the rationale for the update at the workshop.

“First in 2003, in Newma