PCR-based detection of an emerging avian pneumovirus in US turkey flocks

Avian pneumovirus (APV) or turkey rhinotracheitis virus (TRTV) is an import ant respiratory pathogen of domesticated poultry in many countries in Europ e, Africa, and Asia. Until recently, the United States was considered free of APV. In late 1996, an atypical upper respiratory tract infection appeare d in turkey flocks in Colorado and shortly thereafter in turkey flocks in M innesota. An avian pneumovirus (APV-US) that was serologically distinct fro m the previously described TRTV was isolated as the primary cause of the ne w syndrome. The nucleotide sequence of a fragment of the APV-US fusion gene was determined and used to develop a polymerase. chain reaction-based assa y that specifically detects APV-US viral nucleic acid sequences in RNA extr acts of tracheal swabs and turbinate homogenates. The assay is highly sensi tive in that it can detect <0.01 TCID50 of APV. The availability of this as say enables the rapid and accurate determination of APV-US in infected poul try flocks.