Recombination and Transmission Studies with Influenza Virus
Abstract
A recombinant influenza virus X-31 which is antigenically identical with the new Hong Kong (HK) variants but which grows to high yields in chick embryos, has been produced by hybridization of the standard Aichi vaccine strain with Ao/PR8 virus. With this virus, purified inactivated vaccine was produced by Evans Medical Ltd. in England for clinical trials in the United States under the auspices of the Commission on influenza. Correlative and comprehensive studies of the X-31 vaccine and standard HK/Aichi vaccine of matched CCA activity have been conducted in mice, rabbits and man in 6 different laboratories. These studies demonstrated: (1) Significant protection of volunteers from experimental influenza was afforded by both vaccines as determined by reduction in illness and shedding of virus after challenge; (2) The efficacy of X-31 vaccine in preventing natural infection at Fort Ord; 104 hospitalized cases of influenza were found among the 7,934 controls (1.3%), while only 6 (0.36%) occurred in the 1,682 vaccines (p=<0.002). (3) That immunogenicity in experimental animals correlated well with antigenicity and protection data in man. It was possible to distinguish between the two vaccines on the basis of their relative effects on human and mouse ID50 and their capacity to stimulate the production of hemagglutination-inhibiting, neutralizing and plague-inhibiting antibody. The differing immunogenicity of the two vaccines was not predictable from their CCA concentrations, which did not differ significantly.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1970
- Accession Number
- AD0873704
Entities
People
- Edwin D. Kilbourne
Organizations
- Icahn School of Medicine at Mount Sinai