VKM Report 2018: 16 Factors that can contribute to spread of CWD – an update on the situation in Nordfjella, Norway Opinion of the Panel on biological hazards of the Norwegian Scientific Committee for Food and Environment Report from the Norwegian Scientific Committee for Food and Environment (VKM) 2018: 16 Factors that can contribute to spread of CWD – an update on the situation in Nordfjella, Norway Opinion of Panel on biological hazards of the Norwegian Scientific Committee for Food and Environment 13.12.2018 ISBN: 978-82-8259-316-8 ISSN: 2535-4019 Norwegian Scientific Committee for Food and Environment (VKM) Po 222 Skøyen 0213 Oslo Norway Phone: +47 21 62 28 00 Email: [email protected] vkm.no vkm.no/English Cover photo: Wild reindeer visiting a mineral lick in early spring. Aerial photo by Roy Andersen, NINA. Suggested citation: VKM, Bjørnar Ytrehus, Danica Grahek-Ogden, Olav Strand, Michael Tranulis, Atle Mysterud, Marina Aspholm, Solveig Jore, Georg Kapperud, Trond Møretrø, Truls Nesbakken, Lucy Robertson, Kjetil Melby, Taran Skjerdal. (2018) Factors that can contribute to spread of CWD – an update on the situation in Nordfjella, Norway. Opinion of the Panel on biological hazards. ISBN: 978-82-8259-316-8. Norwegian Scientific Committee for Food and Environment (VKM), Oslo, Norway. VKM Report 2018: 16 Factors that can contribute to spread of CWD – an update on the situation in Nordfjella, Norway Preparation of the opinion The Norwegian Scientific Committee for Food and Environment (Vitenskapskomiteen for mat og miljø, VKM) appointed a project group to answer the request from the Norwegian Food Safety Authority. The project group consisted of one VKM member of the Panel on Microbial Ecology, two external experts and a project leader from the VKM secretariat. An external referee commented on and reviewed the manuscript. The VKM Panel on biological hazards evaluated and approved the final opinion drafted by the project group. Authors of the opinion Members of the project group that contributed to the drafting of the opinion (in alphabetical order after chair of the project group): Bjørnar Ytrehus – Chair of the project group and member of the Panel on Microbial Ecology. Affiliation: 1) VKM; 2) Norwegian Institute for Nature Research (NINA) Danica Grahek-Ogden – Project leader from the VKM secretariat. Affiliation: VKM Atle Mysterud - Member of the project group. Affiliation: 1) University of Oslo (UiO) Olav Strand - Member of the project group. Affiliation: 1) Norwegian Institute for Nature Research (NINA) Michael Tranulis – Member of the project group. Affiliation: 1) Norwegian University of Life Sciences (NMBU) Members of the Panel on biological hazards that contributed to the assessment and approval of the opinion (in alphabetical order): Marina Elisabeth Aspholm - Affiliation: 1) VKM; 2) Norwegian University of Life Sciences (NMBU) Solveig Jore – Affiliation: 1) VKM; 2) Norwegian Institute of Public Health (NIPH) Georg Kapperud – Affiliation: 1) VKM; 2) Norwegian Institute of Public Health (NIPH) Kjetil Klaveness Melby - Affiliation: 1) VKM; 2) Oslo University Hospital/ University of Oslo (UiO) Trond Møretrø – Affiliation: 1) VKM; 2) NOFIMA Truls Nesbakken – Affiliation: 1) VKM; 2) Norwegian University of Life Sciences VKM Report 2018: 16 Lucy Robertson – Affiliation: 1) VKM; 2) Norwegian University of Life Sciences Olaug Taran Skjerdal - Affiliation: 1) VKM; 2) Norwegian Veterinary Institute Acknowledgment VKM would like to thank Geir Rune Rauset (Norwegian Institute for Nature Research, NINA) for excellent help with map and GIS analysis and Michael Angeloff (Norwegian Institute for Bioeconomy, NIBIO) for kindly providing data on sheep grazing and farming. Erling Solberg (Norwegian Institute for Nature Research, NINA), Erling Meisingset (Norwegian Institute of Bioeconomy Research, NIBIO) and Christer Rolandsen (Norwegian Institute for Nature Research, NINA) are thanked for their contribution on moose, red deer and roe deer population development and movement patterns, and André Høva, Torodd Urnes and several other officers in Norwegian Food Safety Authority (NFSA) for sharing knowledge and data on the efforts performed to combat CWD. We are also in debt to Runar S. Bjøberg and Asgrim Opdal in Filefjell reinlag who shared knowledge about their reindeer herd, and Harald Skjerdal in Aurland fjellstyre who gave us information about his work to prevent contact between Zone 1 and 2. We are also thankful to Roar Gudding (VKM and Norwegian Veterinary Institute) for providing constructive criticism. Competence of VKM experts Persons working for VKM, either as appointed members of the Committee or as external experts, do this by virtue of their scientific expertise, not as representatives for their employers or third party interests. The Civil Services Act instructions on legal competence apply for all work prepared by VKM. VKM Report 2018: 16 Table of Contents Summary ................................................................................................................ 7 Sammendrag på norsk ......................................................................................... 11 Background and terms of reference as provided by the Norwegian Food Safety Authority ...................................................................................................... 15 1 Introduction ................................................................................................. 16 Definitions of areas described in this report ............................................................ 17 Management actions already enforced ................................................................... 18 Eradication of affected herd ....................................................................... 19 Nation-wide surveillance for CWD ............................................................... 19 Efforts to eliminate “hotspots” for transmission ............................................ 20 Efforts to minimize entry and transit of wild or semi-domesticated reindeer into Zone 1 24 Population reduction in neighbour areas ...................................................... 25 Scientific projects initiated .................................................................................... 25 Bioassay experiments in laboratory rodents ................................................. 25 Oral inoculation of newborn lambs with VRQ/VRQ PrP genotype .................... 26 Samples of rectal tissue and faeces from sheep that have grazed in Nordfjella Z1 26 PRNP-genetic analysis of cervids in Fennoscandia ........................................ 27 Supplementary salt licks as a potential transmission hot spot for CWD prions . 27 2 Literature search .......................................................................................... 28 Relevance screening............................................................................................. 28 3 Hazard identification and characterisation .................................................. 28 Environmental reservoirs ...................................................................................... 28 Transmission of prions and the transmission barrier ................................................ 30 Carriers of disease ............................................................................................... 33 “Preclinical carriers”: Animals shedding infectious prions during the incubation period 33 “Nonclinical carrier” ................................................................................... 35 “Latent carriers”: ....................................................................................... 36 “Passive carrier”: ....................................................................................... 36 n-No biological mechanical transport of CWD prions ...................................... 38 Cervids in Nordfjella ............................................................................................. 38 Wild reindeer ............................................................................................ 38 VKM Report 2018: 16 3.4.1.1 Large scale drivers and factors external to Nordfjella ................................. 38 3.4.1.2 Local drivers in Nordfjella ........................................................................ 40 3.4.1.3 Translocation of reindeer from Nordfjella to other areas. ............................ 41 Semi-domesticated reindeer in Filefjell Reinlag ............................................. 42 Red deer .................................................................................................. 46 Moose ...................................................................................................... 46 Roe deer .................................................................................................. 47 Domestic animals grazing in Nordfjella ................................................................... 47 Use of mineral licks .............................................................................................. 52 Mineral licks and animal movements ........................................................... 54 The difficulty of restoring mineral licks ................................................................... 54 Human activities in Nordfjella ................................................................................ 56 4 Exposure characterisation ............................................................................ 58 Environmental contamination