Salt-dependent haemagglutinating measles virus in S.S.P.E.

Two strains fo S.S.P.E. virus show both haemagglutinin and salt-dependent haemagglutinin. These properties are associated with distinct plaque forms within each strain. The existence of salt-dependent strains in wild-type measles virus suggests that they should be found in the early isolates of all strains of S.S.P.E.