[Immunization with live attenuated A/H5N1 vaccine protects guinea pigs from reinfection].

Cold-adapted influenza virus A/HK/1/68/162/35(H3N2) was developed as unified donor of attenuation and high reproductive capacity forvaccine strains. The reassortant of this donor with surface antigens of highly pathogenic strain Alchicken/Astana/6/05 (H5N1) was tested in guinea pigs as a live or inactivated preparation. Immunization with both formulations induced equal levels of serum virus specific antibodies, while the level of mucosal antibodies was significantly higher in animals immunized with live virus.

[Vaccines against highly pathogenic influenza viruses of the avian origin].

Worldwide spreading of H5 and H7 highly pathogenic influenza viruses of the avian origin, which periodically infect and kill humans without prior adaptation, poses a constant threat of the new pandemic. The effectiveness of the pandemic prevention completely depends on the quality of the existing influenza vaccines. Typical methods of the vaccine production from the antigenically relevant strains are problematic in case of high virulent H5 and H7 viruses.

[Preclinical studies of live intranasal H5N1 influenza vaccine with the deleted HS1 gene].

The paper gives the results of evaluating the efficiency of deINS1 pandemic H5N1 vaccine candidate VN1203delNS1 which was constructed by reverse genetics on the basis of influenza virus strain A/Vietnam/1203/04. The safety, immunogenicity and cross-protection of the vaccine strain against different H5N1 virus clades were demonstrated in mouse and macaque models. The results showed the possibility of designing a new-generation replication-deficient intranasal influenza vaccine, by applying an approach to deleting the NS1 pathogenicity factor, an antagonist of the interferon system.

[Interference and its overcoming during the reproduction of 2 influenza A virus strains in an experiment].

The interference between two influenza A virus strains was investigated in vivo. In mixed infection of chick embryos or mice two results were observed: maximal reproduction of both strains or interference which resulted in a reduction of reproduction activity, antibody production, or virulence of one of the viruses. No interference was observed upon inoculation of two strains apathogenic for the study host combined with an equal concentration of an infectious virus.

[The inoculation properties of live recombinant influenza vaccine types A and B used separately and jointly in children 3 to 14].

The reactogenicity and immunizing activity of vaccine influenza virus A (H1N1) and B strains used as mono- and bi-preparations in children of 3 to 14 years was studied. No increased reactogenicity after the use of bivaccine was observed in the children. Febrile reactions as well as 9 other clinical symptoms which could indicate the reactogenicity of the vaccines were identical for mono- and bivaccine and corresponded to the requirements of the technical documents for the vaccine.

[The ts phenotype of reisolates from children inoculated with live cold-adapted influenza vaccine type A].

Using mutants of fowl plague virus (FRV) which have single temperature-sensitive (ts) mutations in some genes, an analysis was carried out on reisolates from children of 3-6 years, vaccinated with a monovaccine from recombinant strains of influenza type A virus. The recombinants were obtained by crossing of current epidemic strains of subtypes A (HINI) and a (H3N2) with the cold-adapted (XA) ts-donor of attenuation A/Leningrad/134/47/57 (H2N2) from which they, as a rule, inherited 5 ts-mutations in genes 1 (PB2), 2 (PB1), 5 (NP), 7 (M), and 8 (NS). All the reisolates were shown to retain the ts-phenotype.