Update on chronic wasting disease (CWD) III

chronic, wasting, cervids, strain, risk, zoonotic
First published in the EFSA Journal
11. November 2019
Adopted
26. September 2019
Type
Scientific Opinion

Abstract

The European Commission asked EFSA for a Scientific Opinion: to revise the state of knowledge about the differences between the chronic wasting disease (CWD) strains found in North America (NA) and Europe and within Europe; to review new scientific evidence on the zoonotic potential of CWD and to provide recommendations to address the potential risks and to identify risk factors for the spread of CWD in the European Union. Full characterisation of European isolates is being pursued, whereas most NA CWD isolates have not been characterised in this way. The differing surveillance programmes in these continents result in biases in the types of cases that can be detected. Preliminary data support the contention that the CWD strains identified in Europe and NA are different and suggest the presence of strain diversity in European cervids. Current data do not allow any conclusion on the implications of strain diversity on transmissibility, pathogenesis or prevalence. Available data do not allow any conclusion on the zoonotic potential of NA or European CWD isolates. The risk of CWD to humans through consumption of meat cannot be directly assessed. At individual level, consumers of meat, meat products and offal derived from CWD‐infected cervids will be exposed to the CWD agent(s). Measures to reduce human dietary exposure could be applied, but exclusion from the food chain of whole carcasses of infected animals would be required to eliminate exposure. Based on NA experiences, all the risk factors identified for the spread of CWD may be associated with animals accumulating infectivity in both the peripheral tissues and the central nervous system. A subset of risk factors is relevant for infected animals without involvement of peripheral tissues. All the risk factors should be taken into account due to the potential co‐localisation of animals presenting with different disease phenotypes.

Panel members at the time of adoption

Kostas Koutsoumanis, Ana Allende, Avelino Alvarez‐Ordoñez, Declan Bolton, Sara Bover‐Cid, Marianne Chemaly, Robert Davies, Alessandra De Cesare, Lieve Herman, Friederike Hilbert, Roland Lindqvist, Maarten Nauta, Luisa Peixe, Giuseppe Ru, Marion M. Simmons, Panagiotis Skandamis and Elisabetta Suffredini.
Panel on Biological Hazards
Contact
biohaz [at] efsa.europa.eu
doi
10.2903/j.efsa.2019.5863
EFSA Journal 2019;17(11):5863
Question Number
On request from
European Commission