Isolation of avian pneumovirus from mallard ducks that is genetically similar to viruses isolated from neighboring commercial turkeys.

Our earlier studies demonstrating avian pneumovirus (APV) RNA in wild geese, sparrows, swallows, starlings and mallard ducks suggested that wild birds might be involved in the circulation of APV in the United States. To determine whether turkey virus can be transmitted to the free flying birds, we placed APV-negative mallard ducks next to a turkey farm experiencing a severe APV outbreak and in an area with a large population of waterfowls. The sentinel ducks did not develop clinical APV disease but infectious APV (APV/MN-12) was recovered from choanal swabs after 2 weeks, and anti-APV antibodies detected after 4 weeks. Four APV isolates recovered from the neighboring turkeys that were experiencing an APV outbreak at the same time shared 95-99% nucleotide identity and 97-99% predicted amino acid identity with the duck isolate. In addition experimental infection of turkey poults with APV/MN-12 resulted in detection of viral RNA in nasal turbinates and APV-specific IgG in serum. These results indicate that the APV isolates from turkeys and ducks shared a common source, and the viruses from different avian species can cross-infect.