Estimation of the probability of freedom from bovine virus diarrhoea virus in Norway using scenario tree modelling

Madelaine Norström; Malin E Jonsson; Johan Åkerstedt; Anne Cathrine Whist; Anja Bråthen Kristoffersen; Ståle Sviland; Petter Hopp; Helene Wahlström

doi:10.1016/j.prevetmed.2014.06.012

Estimation of the probability of freedom from bovine virus diarrhoea virus in Norway using scenario tree modelling

Prev Vet Med. 2014 Sep 1;116(1-2):37-46. doi: 10.1016/j.prevetmed.2014.06.012. Epub 2014 Jul 3.

Authors

Madelaine Norström¹, Malin E Jonsson², Johan Åkerstedt³, Anne Cathrine Whist⁴, Anja Bråthen Kristoffersen⁵, Ståle Sviland⁶, Petter Hopp⁷, Helene Wahlström⁸

Affiliations

¹ Norwegian Veterinary Institute, P.O. Box 750 Sentrum, NO-0106 Oslo, Norway. Electronic address: madelaine.norstrom@hotmail.com.
² Norwegian Veterinary Institute, P.O. Box 750 Sentrum, NO-0106 Oslo, Norway. Electronic address: malin.jonsson@vetinst.no.
³ Norwegian Veterinary Institute, P.O. Box 295, NO-4303 Sandnes, Norway. Electronic address: johan.akerstedt@vetinst.no.
⁴ Norwegian School of Veterinary Sciences, Department of Production Animal Clinical Sciences, P.O. Box 8146 Dep. , NO-0033 Oslo, Norway. Electronic address: anne.c.whist@nvh.no.
⁵ Norwegian Veterinary Institute, P.O. Box 750 Sentrum, NO-0106 Oslo, Norway. Electronic address: anja.kristoffersen@vetinst.no.
⁶ Norwegian Veterinary Institute, P.O. Box 750 Sentrum, NO-0106 Oslo, Norway. Electronic address: stale.sviland@vetinst.no.
⁷ Norwegian Veterinary Institute, P.O. Box 750 Sentrum, NO-0106 Oslo, Norway. Electronic address: petter.hopp@vetinst.no.
⁸ National Veterinary Institute, Department for Disease Control and Epidemiology, Zoonosis Center, SE-751 89 Uppsala, Sweden. Electronic address: helene.wahlstrom@sva.se.

PMID: 25037848
DOI: 10.1016/j.prevetmed.2014.06.012

Abstract

Disease caused by Bovine virus diarrhoea virus (BVDV) is notifiable in Norway. An eradication programme started in 1992. The number of herds with restrictions decreased from 2950 in 1994 to zero at the end of 2006. From 2007, the aim of the programme has been surveillance in order to document freedom from the infection. To estimate the probability of freedom from BVDV infection in the Norwegian cattle population by the end of 2011, a scenario tree model of the surveillance program during the years 2007-2011 was used. Three surveillance system components (SSCs) were included in the model: dairy, beef suckler sampled at farms (2007-2010) and beef suckler sampled at slaughterhouses (2011). The design prevalence was set to 0.2% at herd level and to 30% at within-herd level for the whole cattle population. The median probability of freedom from BVDV in Norway at the end of 2011 was 0.996; (0.995-0.997, credibility interval). The results from the scenario tree model support that the Norwegian cattle population is free from BVDV. The highest estimate of the annual sensitivity for the beef suckling SSCs originated from the surveillance at the slaughterhouses in 2011. The change to sampling at the slaughterhouse level further increased the sensitivity of the surveillance.

Keywords: Bovine virus diarrhoea; Cattle; Freedom from disease; Norway; Scenario tree model; Surveillance.

MeSH terms

Animal Husbandry
Animals
Bovine Virus Diarrhea-Mucosal Disease / epidemiology*
Bovine Virus Diarrhea-Mucosal Disease / virology
Cattle
Cattle Diseases / epidemiology*
Cattle Diseases / virology
Diarrhea Viruses, Bovine Viral / physiology*
Female
Male
Models, Theoretical*
Norway / epidemiology
Prevalence
Probability Theory