Potency of an inactivated avian influenza vaccine prepared from a non-pathogenic H5N1 reassortant virus generated between isolates from migratory ducks in Asia.
A reassortant influenza virus, A/duck/Hokkaido/Vac-1/2004 (H5N1) (Dk/Vac-1/04), was generated between non-pathogenic avian influenza viruses isolated from migratory ducks in Asia. Dk/Vac-1/04 (H5N1) virus particles propagated in embryonated chicken eggs were inactivated with formalin and adjuvanted with mineral oil to form a water-in-oil emulsion. The resulting vaccine was injected intramuscularly into chickens. The chickens were challenged with either of the highly pathogenic avian influenza virus strains A/chicken/Yamaguchi/7/2004 (H5N1) or A/swan/Mongolia/3/2005 (H5N1) at 21 days post-vaccination (p. v.), when the geometric mean serum HI titers of the birds was 64 with the challenge virus strains. The vaccinated chickens were protected from manifestation of disease signs upon challenge with either of the highly pathogenic avian influenza viruses. However, challenge virus was recovered at low titers from the birds at 2 and 4 days post-challenge (p.c.). All 3 chickens challenged at 6 days p.v. died, whereas 3 chickens challenged at 8 days p.v. survived. These results indicate that the present vaccine confers clinical protection and reduction of virus shedding against highly pathogenic avian influenza virus challenge and should be useful as an optional tool in emergency cases.
Isoda
Norikazu
N
Laboratory of Microbiology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18-jyo Nishi-9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan.
Sakoda
Yoshihiro
Y
Kishida
Noriko
N
Soda
Kosuke
K
Sakabe
Saori
S
Sakamoto
Ryuichi
R
Imamura
Takashi
T
Sakaguchi
Masashi
M
Sasaki
Takashi
T
Kokumai
Norihide
N
Ohgitani
Toshiaki
T
Saijo
Kazue
K
Sawata
Akira
A
Hagiwara
Junko
J
Lin
Zhifeng
Z
Kida
Hiroshi
H
D025041:Animal Migration; D000818:Animals; D000835:Animals, Wild; D000914:Antibodies, Viral / Q000097:blood; D001208:Asia; D002642:Chick Embryo; D002645:Chickens; D004372:Ducks / Q000821:virology*; D053124:Influenza A Virus, H5N1 Subtype / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D009980:Influenza A virus / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D016865:Reassortant Viruses / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D017201:Virus Shedding
D000914:Antibodies, Viral; D007252:Influenza Vaccines; D015164:Vaccines, Inactivated