Recent epidemiology and ecology of influenza A viruses in avian species in Europe and the Middle East

There have been at least ten distinct outbreaks of LPAI or HPAI in poultry caused by H5 or H7 viruses in the last eight years in Europe and the Middle East. There appears to be an increased occurrence of such episodes consistent with global trends. As a result, surveillance systems have been enhance...

Full description

Saved in:
Bibliographic Details
Published inDevelopments in biologicals Vol. 124; p. 45
Main Authors Brown, I H, Banks, J, Manvell, R J, Essen, S C, Shell, W, Slomka, M, Londt, B, Alexander, D J
Format Journal Article
LanguageEnglish
Published Switzerland 2006
Subjects
Animals
Biological Evolution
Birds
Disease Outbreaks - veterinary
Europe - epidemiology
Humans
Influenza A virus - genetics
Influenza A virus - pathogenicity
Influenza in Birds - epidemiology
Middle East - epidemiology
Population Surveillance - methods
Poultry
Middle East
Europe
Online AccessGet more information

Cover

More Information
Summary:There have been at least ten distinct outbreaks of LPAI or HPAI in poultry caused by H5 or H7 viruses in the last eight years in Europe and the Middle East. There appears to be an increased occurrence of such episodes consistent with global trends. As a result, surveillance systems have been enhanced to facilitate early detection of infection in poultry, together with active surveillance of wild bird populations. These complementary activities have resulted in the detection of a number of viruses in wild bird populations, including some with high genetic similarity to newly detected viruses in poultry, for example, H7N3 in Italy and H7N7 in the Netherlands. Furthermore, there is evidence for continued circulation of H5 and H7 viruses in wild Anseriformes, thereby presenting a real and current threat for the introduction of viruses to domestic poultry, especially those reared in outdoor production systems. Viruses of H9N2 subtype continue to circulate widely in the Middle East and are associated with significant disease problems in poultry. The epidemiology has the potential to be complicated further by introduction of novel viruses through illegal importation of captive birds, such as was detected with H5N1 in Belgium in 2004. Continual genetic exchange in the avian virus gene pool and independent evolution of all gene segments either within an individual host species or among wild bird hosts suggests that these viruses are not in evolutionary stasis in the natural reservoir.
ISSN:1424-6074