H7N7 HPAI in commercial chicken layers in Italy

386

The Italian Authorities have reported an outbreak of H7N7 HPAI in commercial chicken layers in Italy (Ferrara region). All 17,000 birds have been humanely destroyed. Restriction zones have been put in place in line with EU rules. In addition, this month two outbreaks of LPAI have been reported in Italy; one of H5N2 LPAI in poultry breeder of various species in Pordenone region, as part of the national surveillance programme and one of H7N7 LPAI in a holding of ornamental birds in Ferrara region, where birds were sampled as part of pre-movement testing requirements for entry at an exhibition. According to the Italian Authorities, the LPAI and HPAI H7N7 viruses are phylogenetically distinct and represent two separate incursions.

At present, it is not clear if the Italian HPAI case is the result of an initial incursion with an LPAI virus and consequent mutation, or initial incursion of a HPAI virus however the most probable explanation is that there has been an undetected incursion of LPAI H7N7 virus which has mutated to HPAI as it spread through the flock. The Italian Authorities reported very sudden onset of increased mortality and drop in egg production which they suggest means the an HPAI incursion; however clinical signs of LPAI viruses in poultry, even galliforme poultry, can be difficult to detect, as it relies on record keeping for food and water intake as well as production records.

NEWS.H7N7 HPAI in commercial chicken layers in Italy

For more information: https://www.gov.uk/government/collections/animal- diseases-international-monitoring