Zakstelskaja, L Ja. (Ivanovsky Institute of Virology, AMS, Moscow D-98, USSR), N. A. Evstigneeva, V. A. Isachenko, S. Ph. Shenderovitch and V. A. Eflmova. Influenza in the USSR: New antigenic variant A2/Hong Kong/1/68 and its possible precursors. Amer. J. Epid. 1969, 90: 400-405.-Thf A2/Hong Kong-like influenza strains appeared in the USSR in December, 1968 and initiated large outbreaks. By employing HI tests with hyperimmune rat antisera, an antigenic relationship was demonstrated between A2/Hong Kong/1/68 and influenza A strains isolated from ducks in the USSR. Influenza virus strain A2/Hong Kong/1/68 is antigenically distinct from previously isolated A2 influenza strains and the authors propose that it be designated as a third variant of the A2 subtype. Virus neutralizing and HI antibodies to influenza A2/Hong Kong/1/68 were detected in serum samples collected in 1960 from men born before 1892. These findings suggest that strains related to the A2/Hong Kong/68 strain circulated in the human population about 80 years ago. © 1969, by THE JOHNS HOPKINS UNIVERSITY.
