“…The association of this particular virus with aseptic meningitis, often accompanied by a rubelliform rash, was first observed in 1956 (Tyrrell and Snell, 1956;McLean and Cameron, 1957). On many subsequent occasions frank epidemics of meningitis, sharply circumscribed in time and place, have occurred with evidence of direct spread within families (Sanford and Sulkin, 1959;Sabin, Krumbiegal, and Wigand 1958;Sabin 1960).…”