Virological investigation of avian influenza virus on postglacial species of phasianidae and tetraonidae in the italian alps.

Land-based birds, belonging to Galliformes order are considered to be potential intermediaries in the emergence of new strains of influenza A viruses (AIVs), but the viral circulation in these birds remains largely unknown. To gain insights into the circulation of AIV in the wild Galliformes populations in Italian Alps, we conducted a virological survey on rock partridge (Alectoris graeca saxatilis) belonging to Phasianidae family and on tetraonids including rock ptarmigan (Lagopus mutus helveticus) and black grouse (Tetrao tetrix tetrix). In 2003 and 2004, during the hunting seasons, 79 wild Galliformes, categorised into age and sex classes, were hunted in the Sondrio Province (Central Alps). Cloacal swabs were collected from 11 rock partridges and from 68 tetraonids including 23 alpine rock ptarmigans and 45 black grouses. We tested cloacal swabs by a high sensitive reverse transcription- (RT-) PCR detecting the matrix gene of AIV. No AIV was detected in the investigated samples, thus, suggesting the lack of AIV circulation in these relict populations in the study period. In terms of threatened species conservation, during wildlife management activities, it is very important to exclude the introduction of AIV-carrier birds in shared territories, a fact representing a health risk for these populations.

Avian influenza and animal health risk: conservation of endemic threatened wild birds in Sardinia Island.

Sardinia is a Mediterranean island with a long geological history, leading to a separation process from continental Europe during the Miocene. As a consequence, in this insular habitat some wild bird species developed endemic forms, some of which are currently threatened. The aim of this study is to evaluate the possible animal health risk associated with a potential avian influenza virus (AIV) circulation in Sardinian wild bird populations. Overall, 147 cloacal swabs were sampled in the Sardinia region from June 2009 to September 2011. Samples were obtained from 12 taxonomic orders, including 16 families and 40 species of birds. Based on the endangered host status or on the ecology of the host-virus interaction, samples were categorized into three groups of species: 1) endemic, endangered, or both (17 species); 2) potential reservoir (21 species); and 3) potential spillover (two species). Cloacal swabs were tested by reverse transcription (RT)-PCR for influenza A virus matrix gene amplification. Forty-one serum samples were tested by nucleoprotein-enzyme-linked immunosorbent assay (NP-ELISA) for antibodies against influenza A virus nucleoprotein and by hemagglutination inhibition assay for detection of seropositivity against H5 and H7 AIV subtypes. No cloacal swabs tested RT-PCR positive for AIV, whereas two weak seropositive results were detected by NP-ELISA in a mallard (Anas platyrhynchos) and in a yellow-legged gull (Larus michahellis). The low or absent AIV circulation detected in Sardinia's wild birds during the study suggests a naïve status in these avian populations. These data provide new information on AIV circulation in Sardinia's wild birds that could be applied to implement conservation strategies for threatened species.