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Background: infectious low pathogenic avian influenza viruses (LPaIVs) have been recently detected on feathers of wild ducks. Laboratory trial results suggested that the preen oil gland secretion, covering waterbirds’ feathers, may attract and concentrate virus particles from aIV-contaminated waters to birds’ bodies. We evaluated whether ducks can become infected by the ingestion of preen oil-associated viral particles, experimentally smeared on their plumage. In addition, we compared virologic and serologic results obtained from mallards whose feathers were experimentally infected, with those from wild mallards naturally carrying aIVs on feathers.Methods: we experimentally coated 7 mallards (anas plathyrynchos) using preen oil mixed with a LPaIV (h10n7 subtype), and housed them for 45 days with a control, uncoated duck. cloacal, oropharyngeal and feather swabs were collected from all birds and examined for aIV molecular detection and isolation. Blood samples were also taken to detect influenza specific antibodies. In addition, sera from 10 wild mallards, carrying on feathers infectious LPaIV h10n7, were examined.Results: virologic and serologic results indicated that through self- and allopreening all the birds experimentally coated with the preen oil/aIV mix and the control duck ingested viruses covering feathers and became infected. Virus isolation from feathers was up to 32 days post-coating treatment. one out of 8 wild mallards showing antibodies against type a influenza virus was seropositive for h10 subtype too.Conclusions: our experimental and field results show evidences suggesting that uninfected birds carrying viruses on their feathers, including immune ones, might play an active role in spreading aIV infection in nature. For this reason, routine aIV surveillance programs, aimed at detecting intestinal and/or respiratory viruses, should include the collection of samples, such as feather swabs, enabling the detection of viruses sticky to preened birds’ bodies....

A molecular and serological survey was performed in order to investigate the role of some wild avian species in the epidemiology of Avian Pneumovirus (APV) infection. During 2001, 440 aquatic birds, including sea gulls, terns, herons, flamingos and shorebirds, were sampled in north-eastern wetlands of Italy. According to the taxonomic group, the sample sizes were: 179 Laridae, 161 Sternidae, 46 Ardeidae, 35 Phoenicopteridae, 19 Scolopacidae. Swabs from the choanal cleft were collected from 394 of these birds and tested by a subtype-specific RT-nested PCR, based on oligonucleotides specific for G gene sequence and able to differentiate A and B subtypes. At the same time, whenever possible, blood samples were collected (n. 368) and analysed using a blocking ELISA serological assay. All molecular and serological tests produced negative results.

Pheasant coronavirus (PhCoV) has been isolated in the UK and Italy in the last few decades. A serological survey was carried out in the Emilia-Romagna Region (Northern Italy) in order to establish the occurrence and spread of coronavirus infection in farm-bred and free-living pheasants. Seven hundred and four sera were obtained during 1998 from 16 game farms. 275 sera were collected from 1995 to 2002 from free-living pheasants, belonging to a natural population: these were classified as “wild” and “restocked” (a few reared birds released in the study area). A blocking ELISA (Svanovir) test was employed for the detection of antibodies cross reactive to Infectious Bronchitis Virus in sera. Seropositive animals were detected in 5 out 16 game farms examined, while only two free-living pheasants (a restocked bird and an unclassified one) were seropositive. These data confirm that the infection was present in Italian-reared pheasants, but the free-living sampled population appeared to be free from the infection. The authors emphasise the risk of spreading the infection to wild bird populations by game restocking activities.