Abstract
In the province of Voyvodina 18 cases of post-vaccinal encephalitis have been recorded, three of which were fatal.The estimated morbidity rate was 0.6 per 10(5) after revaccination, and 3.9 per 10(5) after primary vaccination. The virological studies described, as well as other findings referred to in this report, are consistent with the possibility of an autoimmune aetiology of the post-vaccinal encephalitis cases observed.