ARS | Publication request: OUTBREAKS OF HIGHLY PATHOGENIC AVIAN INFLUENZA (H5N2) IN ITALY DURING OCTOBER 1997 TO JANUARY 1998

Submitted to: Avian Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 15, 1999
Publication Date: November 1, 1999

Interpretive Summary: Highly pathogenic avian influenza is a viral disease in poultry that can cause high death losses and stop international trade in poultry & poultry products. An outbreak of highly pathogenic influenza virus and its control were reported for Northern Italy during the fall, 1997 and winter,1998. An H5N2 avian influenza virus was responsible for the outbreak. The source of fthe virus is unknown. Eradication was achieved by quarantine, testing and depopulation of infected flocks.

Technical Abstract: Between the month of October 1997 and January 1998, eight outbreaks of highly pathogenic avian influenza were diagnosed in the Veneto and Friuli-Venezia Giulia regions in north-eastern Italy. For each of the eight outbreaks, influenza A virus of subtype H5N2 was isolated and the inoculation of susceptible chickens confirmed these viruses to be extremely yvirulent with intravenous pathogenicity indices in 6-week-old chickens of 2.98 to 3.00. Although it was not possible to trace the origin of infection, the epidemiological investigation revealed connections between several outbreaks and emphasized the well-known risk factors for avian influenza such as bird movement, rearing of mixed populations and contact with migratory waterfowl. Control measures listed in European Union directive 92/40/EEC were implemented promptly and spread of the infection to intensively-reared domestic poultry was avoided.