Isolation of an attenuated myxoma virus field strain that can confer protection against myxomatosis on contacts of vaccinates

Twenty MV strains obtained from a survey of field strains currently circula ting throughout Spain were analyzed for their virulence and horizontal spre ading among rabbits by contact transmission. A virus strain with suitable c haracteristics to be used as a potential vaccine against myxomatosis in wil d rabbit populations was selected. Following inoculation, the selected MV s train elicited high levels of MV specific antibodies and induced protection of rabbits against a virulent MV challenge. Furthermore, the attenuated MV was transmitted to 9 out of 16 uninoculated rabbits by contact, inducing p rotection against myxomatosis.