Safety, immunogencity, and efficacy of a cold-adapted A/Ann Arbor/6/60 (H2N2) vaccine in mice and ferrets.
We studied the attenuation, immunogenicity and efficacy of the cold-adapted A/Ann Arbor/6/60 (AA ca) (H2N2) virus in mice and ferrets to evaluate its use in the event of an H2 influenza pandemic. The AA ca virus was restricted in replication in the respiratory tract of mice and ferrets. In mice, 2 doses of vaccine elicited a >4-fold rise in hemagglutination-inhibition (HAI) titer and resulted in complete inhibition of viral replication following lethal homologous wild-type virus challenge. In ferrets, a single dose of the vaccine elicited a >4-fold rise in HAI titer and conferred complete protection against homologous wild-type virus challenge in the upper respiratory tract. In both mice and ferrets, the AA ca virus provided significant protection from challenge with heterologous H2 virus challenge in the respiratory tract. The AA ca vaccine is safe, immunogenic, and efficacious against homologous and heterologous challenge in mice and ferrets, supporting the evaluation of this vaccine in clinical trials.
Chen
Grace L
GL
Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, MD 20892, USA. chengra@niaid.nih.gov
Lamirande
Elaine W
EW
Jin
Hong
H
Kemble
George
G
Subbarao
Kanta
K
D000222:Adaptation, Physiological; D000818:Animals; D003080:Cold Temperature; D005260:Female; D005289:Ferrets; D053121:Influenza A Virus, H2N2 Subtype / Q000235:genetics / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects* / Q000276:immunology*; D008168:Lung / Q000821:virology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009154:Mutation; D009976:Orthomyxoviridae Infections / Q000517:prevention & control* / Q000821:virology*; D014613:Vaccines, Attenuated; D014779:Virus Replication
D007252:Influenza Vaccines; D014613:Vaccines, Attenuated