Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Phylogenetic Analysis of Low-Pathogenicity Avian Influenza H6N2 Viruses from Chicken Outbreaks (2001-2005) Suggest That They Are Reassortants of Historic Ostrich Low-Pathogenicity Avian Influenza H9N2 and H6N8 Viruses (El análisis filogenético de los virus H6N2 de influenza aviar de baja patogenicidad provenientes de un brote en pollos (2001-2005) sugiere que son una recombinación de dos virus de influenza aviar de baja patogenicidad H9N2 y H6N8 de avestruz)

C. Abolnik, S. P. R. Bisschop, G. H. Gerdes, A. J. Olivier and R. F. Horner
Avian Diseases
Vol. 51, No. 1, Supplement: Sixth International Symposium on Avian Influenza (Mar., 2007), pp. 279-284
Stable URL: http://www.jstor.org/stable/4493210
Page Count: 6
  • Read Online (Free)
  • Download ($12.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Phylogenetic Analysis of Low-Pathogenicity Avian Influenza H6N2 Viruses from Chicken Outbreaks (2001-2005) Suggest That They Are Reassortants of Historic Ostrich Low-Pathogenicity Avian Influenza H9N2 and H6N8 Viruses (El análisis filogenético de los virus H6N2 de influenza aviar de baja patogenicidad provenientes de un brote en pollos (2001-2005) sugiere que son una recombinación de dos virus de influenza aviar de baja patogenicidad H9N2 y H6N8 de avestruz)
Preview not available

Abstract

Low-pathogenicity (LPAI) and high-pathogenicity (HPAI) avian influenza viruses are periodically isolated from South African ostriches, but during 2002 the first recorded outbreak of LPAI (H6N2) in South African chickens occurred on commercial farms in the Camperdown area of KwaZulu/Natal (KZN) Province. Sequence analysis of all eight genes were performed and phylogenetic analysis was done based on the hemagglutinin and neuraminidasc sequences. Results from phylogenetic analyses indicated that the H6N2 chicken viruses most likely arose from a reassortment between two South African LPAI ostrich isolates: an H9N2 virus isolated in 1995 and an H6N8 virus isolated in 1998. Two cocirculating sublineages of H6N2 viruses were detected, both sharing a recent common ancestor. One of these sublineages was restricted to the KZN province. The neuraminidase gene contained a 22-amino acid deletion in the NA-stalk region, which is associated with adaptation to growth in chickens, whereas the other group, although lacking the NA-stalk deletion, spread to commercial farms in other provinces. The persistence of particular H6N2 types in some regions for at least 2 yr supports reports from Asia and southern California suggesting that H6N2 viruses can form stable lineages in chickens. It is probable that the ostrich H6N8 and H9N2 progenitors of the chicken H6N2 viruses were introduced to ostriches by wild birds. Ostriches, in which AI infections are often subclinical, may serve as mixing vessels for LPAI strains that occasionally spill over into other poultry. /// Virus de influenza aviar de baja y alta patogenicidad son aislados periódicamente de avestruces en Sur África, pero durante el año 2002 en granjas comerciales del área de Camperdown en la provincia de KwaZulu/Natal se registró el primer brote de influenza aviar de baja patogenicidad (H6N2) en pollos de Sur África. Se realizó el análisis de la secuencia de todos los ocho genes y el análisis filogenético se hizo basado en la secuencia de los genes que codifican para la hemaglutinina y la neuraminidasa. Los resultados de los análisis filogenéticos indican que los virus de pollo H6N2 muy probablemente surgieron de la recombinación entre dos aislamientos Surafricanos de influenza aviar de baja patogenicidad: un H9N2 aislado en el año 1995 y un H6N8 aislado en el año 1998. Se detectaron dos sublinajes de H6N2 circulando, ambos con un ancestro común. Uno de los sublinajes estaba restringido a la provincia de KwaZulu/Natal. El gen de la neuraminidasa contenía una deleción de 22 aminoácidos en la región del tallo de la proteína, lo cual se asocia con la adaptación a crecer en pollos, mientras el otro grupo, aunque carecía de la deleción en la proteína neuraminidasa, se diseminó a granjas comerciales en otras provincias. La persistencia durante al menos dos años de un tipo particular de H6N2 en algunas de las regiones, apoyan reportes de Asia y del sur de California que sugieren que los virus H6N2 pueden formar linajes estables en pollos. Es probable que los progenitores del virus H6N2 de pollo (H6N8 y H9N2 de avestruz) fueran introducidos en los avestruces por aves silvestres. Las avestruces, donde las infecciones con influenza aviar son comúnmente subclínicas, pueden servir como huéspedes intermediarios para cepas de influenza aviar de baja patogenicidad que ocasionalmente se transmiten a otros tipos de ayes domésticas.

Page Thumbnails

  • Thumbnail: Page 
279
    279
  • Thumbnail: Page 
280
    280
  • Thumbnail: Page 
281
    281
  • Thumbnail: Page 
282
    282
  • Thumbnail: Page 
283
    283
  • Thumbnail: Page 
284
    284