CONTROL OF AUJESZKYS-DISEASE IN SCHLESWIG -HOLSTEIN .2. ERADICATION OF AUJESZKYS-DISEASE FROM A HIGH-INCIDENCE AREA AFTER A 3 YEAR VACCINATION PROGRAM

The prevalence of gI positive breeding herds and that of breeding pigs decreased from 75% to 24.3% and from 27.3% to 3.7%, respectively, wit hin three years after the start of a compulsory vaccination programme. This was followed by a mandatory test and slaughter programme in all breeding herds to eliminate Aujeszky's disease virus from the area. AD -free status was achieved in 746 (83.9%) of 889 herds, the remaining 1 43 herds had to be subject to the re-test eradication programme. At th e end of the first year of this programme the percentage of AD-free he rds increased to 97.4%. Twenty-three herds (2.6%) were found to contai n gI positive animals including three herds which became re-infected a fter the introduction of boars from outside the area. Recently no gI p ositive finishing pigs were found and since 1994 the eradication campa ign has been expanded to the whole area of Schleswig-Holstein