Popis: |
By the antigenic specificity of the surface subunits, hemagglutinin and neuraminidase, the influenza virus strains A (H1N1) isolated in 1977--1978 were related but not identical to the A (H1N1) strains circulating in 1950--1952. The A/FM/1/47 strain differed from the A/England/51, A/Pan/52 strains and A/USSR/090/77 strain by its antigenic relations with the A/Netherland/56 and A/Denver/57 strains. Biologically, the new A/H1N1/77 strains were similar to the reference strains circulating in 1947--1952 by any one feature. |