摘要：Forty four influenza B viruses were isolated and analyzed in an epidemiological survey of infectious disease in Osaka city between 1988 and 1993. Hemagglutination inhibition (HI) test using antisera showed that the antigenicity of the B/OC/19/93 strain isolated in 1993 was clearly distinct from that of the 18 other strains. The B/OC/19/93 strain was similar in antigenicity to the B/Aichi/5/88-like strain of the B/Victoria line, which was not detected in the 1990/91 influenza B virus epidemic in Osaka city. All influenza B viruses detected in the 1990/91 seasons were B/Yamagata 16/88-like strains belonged to the B/Norway line. The HI test revealed that some B virus variants may cocirculate every few years. Thus it was considered that a new B virus of the B/Victoria line may again become the main current in Osaka next influenza epidemic.
