The number of cases submitted to laboratory examination is shown in the following table. In Switzerland, an information campaign was initiated in 1989 to familiarize farmers and veterinarians with the symptoms of BSE, and it is mandatory to notify cattle with suspicion of BSE since 1990. Subsequently, the awareness of the disease was maintained through numerous articles in various journals for veterinarians, farmers and other professionals, and presentations. In addition a video on the clinical signs of BSE was realized. An efficient notification of all suspect cases was guaranteed by full compensation of the animal value and of all the costs related with the management of the case, such as diagnostic, the veterinary practitioners visit, the incineration and others.
Preliminary results exclude a possible association with risk factors other than feed.
In spite of the feed ban, owing to a cross-contamination at feed mill, the resulting level of infectivity in cattle concentrate feed would rarely have reached a critical threshold. A special investigation on BAB cases is in progress. Preliminary results showed no evidence of vertical transmission. Moreover, their export has been prohibited. In Autumn 1996, following the knowledge of the British study on the possible vertical transmission, a campaign to kill all direct offspring of BSE-confirmed cows was started.