Performance of gross lesions at postmortem for the detection of outbreaks during the avian influenza A virus (H7N7) epidemic in The Netherlands in 2003.

A total of 123 submissions (on average, five birds per submission) from poultry flocks with a suspicion of an infection with highly pathogenic avian influenza virus were investigated at postmortem during the 2003 epidemic in The Netherlands. A total of 86 of these submissions were from infected flocks (positive submissions), and 37 submissions were from non-infected flocks (negative submissions). Peritonitis was the most frequently (62%) recorded pathological finding in positive submissions, followed by tracheitis (43%), oedema of the neck and/or wattles (12%) and (petechial) haemorrhages in the proventriculus (4%).