title: Active surveillance for avian influenza viruses in wild birds and backyard flocks in Northern Italy during 2004 to 2006.
abstract: Following the avian influenza epidemics that occurred in Italy between 1997 and 2003, the Italian Ministry of Health in collaboration with veterinary authorities promoted, funded and implemented a national surveillance programme. The main objectives of the surveillance effort were to identify avian influenza viruses circulating in wild birds and to investigate the role of backyard poultry flocks in the dynamics of infection in a densely populated poultry area. Over 2 years (2004 to 2006), 164 backyard flocks and 4083 wild birds (mainly migratory Anseriformes and Charadriiformes) were sampled in three regions in the North of Italy. Samples collected were screened by means of real-time reverse transcriptase-polymerase chain reaction and the positive samples were processed for attempted virus isolation in embryonated fowl's specific pathogen free eggs. At the end of the study period, 27 low-pathogenic avian influenza viruses had been isolated from backyard flocks and 49 strains obtained from wild birds. Of these, 26 belonged to the H5 or H7 subtype and were closely related to contemporary low-pathogenic strains of Eurasian lineage. The findings confirm that backyard free-range farming is at high risk for avian influenza virus introduction, and confirm the role of wild waterfowl in the introduction and perpetuation of low-pathogenic avian influenza viruses during the winter season in Southern Europe.
authors.affiliation: OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy. cterregino@izsvenezie.it
authors.forename: Calogero
authors.initials: C
authors.lastname: Terregino
authors.forename: Roberta
authors.initials: R
authors.lastname: De Nardi
authors.forename: Vittorio
authors.initials: V
authors.lastname: Guberti
authors.forename: Mara
authors.initials: M
authors.lastname: Scremin
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Raffini
authors.forename: Ana Moreno
authors.initials: AM
authors.lastname: Martin
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cattoli
authors.forename: Lebana
authors.initials: L
authors.lastname: Bonfanti
authors.forename: Ilaria
authors.initials: I
authors.lastname: Capua
mesh_terms: D000818:Animals; D000829:Animals, Domestic; D000835:Animals, Wild; D001717:Birds / Q000821:virology*; D009980:Influenza A virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D005585:Influenza in Birds / Q000453:epidemiology* / Q000821:virology*; D007558:Italy / Q000453:epidemiology; D010802:Phylogeny; D011159:Population Surveillance