FIELD: medicine, virology, vaccines. SUBSTANCE: vaccine strain of influenza virus A/17/New Caledonia/99/145 (H1N1) is an reassortant prepared by crossing an epidemic virus A/New Caledonia/20/99 (H1N1) with cold-adapted temperature-sensitive virus A/Leningrad/134/47/57 (H2N2) as a donor of attenuation that is harmless for adults and its properties provide a possibility to obtain reassortant vaccine strains with guarantee from newly appearing epidemic viruses. The strain A/17/New Caledonia/99/145 (H1N1) multiplies actively in developing chicken embryos at optimal temperature 33-34 C, shows temperature- -sensitivity and cold-adaptation. Reassortant inherited two genes from an epidemic virus encoding surface proteins (hemagglutinine and neuraminidase) and six genes encoding nonglycosidated proteins from an attenuation donor. The strain A/17/New Caledonia/99/145 (H1N1) is an areactogenic for adults in an intranasal route of administration. Thus, vaccine strain A/17/New Caledonia/99/145 by biological properties and indices of reactogenicity corresponds to requirements imposing by Pharmacopoeia article PHA 42-3569-98 to vaccine strains for live (anti)-influenza vaccine for intranasal use for adults. EFFECT: new strain indicated above, valuable medicinal properties. 1 tbl, 1 ex
