Titre du document / Document title
New avian influenza A virus subtype combination H5N7 identified in Danish mallard ducks
Auteur(s) / Author(s)BRAGSTAD K.
JØRGENSEN P. H.
HANDBERG K. J.
Résumé / Abstract
During the past years increasing incidences of influenza A zoonosis have made it of uppermost importance to possess methods for rapid and precise identification and characterisation of influenza A viruses. We present herea convenient one-step RT-PCR method that will amplify full-length haemagglutinin (HA) and neuraminidase (NA) directly from clinical samples and from all known subtypes of influenza A. We applied the method on samples collected in September 2003 from a Danish flock of mallards with general health problems and by this a previously undescribed influenza A subtype combination, H5N7, was identified. The HA gene showed great sequence similarity to the highly pathogenic avian influenza A virus (HPAIV) A/Chicken/Italy/312/97 (H5N2); however, the cleavage site sequence between HA1 and HA2 had a motif typical for low pathogenic avian influenza viruses (LPAIV). The full-length NA sequence was most closely related to the HPAIV A/Chicken/Netherlands/01/03 (H7N7) that infected chickens and humans in the Netherlands in 2003. Ten persons with direct or indirect contact with the Danish mallard ducks showed signs of influenza-like illness 2-3 days following the killing of the ducks, but no evidence of influence infections was detected. To our knowledge this is the first report of an H5N7 influenza A virus.
Revue / Journal TitleVirus research
Source / Source
2005, vol. 109, no
2, pp. 181-190 [10 page(s) (article)]
Langue / Language
Editeur / Publisher
Elsevier, Shannon, IRLANDE
Localisation / Location
INIST-CNRS, Cote INIST : 20313, 35400012504818.0090
Nº notice refdoc (ud4) : 16635355