There are several indications that central nervous system (CNS) lesions in visna are immune-mediated and that cell-mediated immunity (CMI) may be of importance in the initiation of the lesions. To study the role of CMI in the pathogenesis of CNS lesions, five sheep were infected by intracerebral ino...

Intracerebral serial passage of visna virus KV1514 through three icelandic sheep was used to select for strains with increased neurovirulence. A strain (KV1772) with increased neuropathogenicity was obtained. We isolated several proviral molecular clones from a plaque-purified biological clone of KV...

Of 730 Icelandic schoolgirls, 12 years of age, screened for rubella antibodies by the haemagglutination-inhibition (HI) technique, 372 (50.9%) were found to be seronegative. Rubella vaccine was administered to 355 members of this group, and to 12 girls with an HI titre of 20. Blood samples were take...