11/09/2009

Pandemic A(H1N1)/09 virus. -- (WIKIPEDIA) -- Recombination A(H1N1) -- H5N1

 

Other experts are also concerned that the new virus strain could mutate over the coming months. Guan Yi, a leading virologist from the University of Hong-Kong, for instance, described the new H1N1 influenza virus as "very unstable", meaning it could mix and swap genetic material when exposed to other viruses. During an interview he said "BothH1N1 and H5N1 are unstable so the chances of them exchanging genetic material are higher, whereas a stable (seasonal flu) virus is less likely to take on genetic material." TheH5N1 virus is mostly limited to birds, but in rare cases when it infects humans it has a mortality rate of between 60% to 70%.  Experts worry about the emergence of a hybrid of the more virulent Asian-lineage HPAI (highly pathogenic avian influenza) A/H5N1 strain (media labeled "bird flu") with more human-transmissible Influenza A strains such as this novel 2009 swine-origin A/H1N1 strain (media labeled "swine flu"), especially since the H5N1 strain is and has been for years endemic in birds in countries like China, Indonesa, Vietnam and Egypt.

 

300px-2009_H1N1_influenza_virus_genetic-num.svg

HA  Hemagglutinin   swine (H1) North America

 

NA Neuraminidase  swine (N1) Europe

 

 

PA  RNA Polymerase subunit  PA avian North America

 

PB1 RNA Polymerase Subunit PB1 human 1993 H3N2 strain 

 

PB2 RNA Polymerase Subunit PB2 avian North America

NP   Nucleoprotein   Swine North America

M     Matrix Protein  M1, M2  Swine Eurasia

                    Non-strutural protéins NS1

NS/NEP                                                             Swine North America

                    NEP Nuclear (Nuclear export protein)

 

GRIPPE_PORCINE-c1f3e

La souche actuelle du virus H1N1 est un mélange de gènes humains, porcins et aviaires. Elle est très contagieuse, mais pas plus meurtrière que le virus de lagrippe saisonnière commune. Toutefois, elle pourrait, en théorie, devenir plus dangereuse en devenant plus virulente, par exemple en se recombinant avec le virus H5N1, ougrippe aviaire, qui est bien plus mortel, mais aussi plus difficile à transmettre chez l'homme. On parle de «réassortiment» ou de «recombinaison» génétique, qui peut intervenir à la faveur d'une infection virale simultanée chez n'importe quel hôte.

 



 

21:08 Écrit par Dr MSFV | Lien permanent | Commentaires (0) |  Facebook |

Les commentaires sont fermés.