title: BVD eradication in Switzerland--a new approach.
abstract: Diverse concepts for BVD eradication or control have been applied in several countries with varying success. Results of previous studies conducted in Switzerland have shown that the prevalence of antibody-positive animals is high and that BVDV is widespread in the country causing serious economic losses. A new approach to eradicate BVD in the cattle population in Switzerland was chosen. It consists in testing the whole Swiss cattle population for virus detection in a short period of time, without initial antibody screening. Identified persistently infected (PI) animals have to be slaughtered, and new herd infections should be avoided by movement restrictions. Ear-notches are collected using special tags for labeling the animals, and are analyzed using ELISA or rtRT-PCR methods. Confirmatory tests if needed are performed on blood samples using rtRT-PCR. The eradication program is divided into four phases: (1) Pre-pasturing phase: all young bovines going to transhumance in summer have to be negative tested before. (2) Initial phase: all non-tested bovines have to be tested. Movement restrictions are effective at the same time. (3) Calves phase: all newborn calves have to be tested. (4) Surveillance phase: several strategies will be compared using a modeling approach. After the pre-pasture phase already 595,230 animals (37% of the livestock) have been tested within four months. A prevalence of 1.1% of PIs was observed. The average age of infected animals is 403 days compared to 794 days for non-infected animals, with the oldest PI-animal being over 11 years old. On average PI-animals are slaughtered within 18 days after the last positive result. The pre-pasture phase has shown that sampling and testing a high number of animals in a short time is challenging but possible. The next phase will deal with double the number of animals in a similar time frame. The coordination between all partners as well as the collaboration of farmers is the key factor for ensuring the success of the program.
authors.affiliation: Federal Veterinary Office, 3003 Bern, Switzerland. patrick.presi@vphi.unibe.ch
authors.forename: P
authors.initials: P
authors.lastname: Presi
authors.forename: D
authors.initials: D
authors.lastname: Heim
mesh_terms: D017677:Age Distribution; D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000453:epidemiology / Q000517:prevention & control*; D002417:Cattle; D001908:Diarrhea Viruses, Bovine Viral; D013557:Switzerland; D013997:Time Factors