title: Differences in the detection of highly pathogenic avian influenza H5N1 virus in feather samples from 4-week-old and 24-week-old infected Pekin ducks (Anas platyrhynchos var. domestica).
abstract: Previous studies have reported the detection of H5N1 HPAI virus in feathers from ducks naturally and experimentally infected and suggested that feather calami (FC) could be used as diagnostic samples for the early detection of H5N1 HPAI infections. Ducks are readily infected with H5N1 HPAI viruses although the development of clinical signs and deaths were reported as age-related with younger birds being more susceptible. The correlation between age and virus localisation in FC of infected ducks has not been studied to date. In the present study juvenile (4-week-old) and adult (24-week-old) Pekin ducks (Anas platyrhynchos var. domestica) were infected experimentally with a clade 2.2 H5N1 HPAI virus (A/duck/Nigeria/1071-23/2007). Tracheal (Tr) and cloacal (Cl) swabs and FC were collected at 3, 5, 7 and 10 days post infection and tested by RRT-PCR and a double antibody sandwich-ELISA (DAS-ELISA) developed in house. Virus was detected in swabs and FC of challenged ducks with a higher rate of detection in juvenile ducks. In this age group virus was detected over a longer period of time in FC compared to swabs. Our study showed that FC samples collected from young ducks are a valid diagnostic specimen for H5N1 HPAI virus detection. The DAS-ELISA on FC proved to be a suitable alternative diagnostic test when molecular and/or virus isolation techniques are not available therefore it could be useful in the diagnosis of H5N1 HPAI infections in under-resourced countries.
authors.affiliation: OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Infectious Diseases at the Human-Animal Interface, Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), Viale dell'Università 10, 35020 Legnaro, PD, Italy. raiello@izsvenezie.it
authors.forename: Roberta
authors.initials: R
authors.lastname: Aiello
authors.forename: Maria Serena
authors.initials: MS
authors.lastname: Beato
authors.forename: Marzia
authors.initials: M
authors.lastname: Mancin
authors.forename: Michela
authors.initials: M
authors.lastname: Rigoni
authors.forename: Aurora Romero
authors.initials: AR
authors.lastname: Tejeda
authors.forename: Silvia
authors.initials: S
authors.lastname: Maniero
authors.forename: Ilaria
authors.initials: I
authors.lastname: Capua
authors.forename: Calogero
authors.initials: C
authors.lastname: Terregino
mesh_terms: D000367:Age Factors; D000818:Animals; D004372:Ducks / Q000821:virology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards; D005241:Feathers / Q000821:virology*; D053124:Influenza A Virus, H5N1 Subtype / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D005585:Influenza in Birds / Q000175:diagnosis* / Q000276:immunology / Q000821:virology; D016133:Polymerase Chain Reaction / Q000592:standards; D015203:Reproducibility of Results; D014132:Trachea / Q000821:virology