Over the last year, avian metapneumovirus (AMPV or Swollen Head syndrome) has been reported in every turkey-producing state in the U.S. AMPV is also present in commercial poultry flocks around the world, affecting not only turkeys, but also chickens and ducks. Wild birds are considered natural reservoirs. AMPV is highly contagious and affects mainly the respiratory and reproductive tracts, leading to respiratory signs and decreased egg production. AMPV infection is often complicated by secondary