LPAI detection in wild birds and LPAI spread between European holdings in the period 2005‐2015

Abstract

The objective of this report is to describe the information provided from European Member States relating to LPAI detection in wild birds and LPAI spread between European holdings. Regarding LPAI outbreaks in poultry holdings in Europe, were collected for 272 LPAI outbreaks occurring in 13 Member States between 2006 and 2015. These consisted of 89 outbreaks of LPAI H5, 72 outbreaks of LPAI H7 and 111 outbreaks where the H subtype was not identified. Overall, France and Italy had the greatest number of LPAI H5 outbreaks between 2006 and 2015 (n=10 and 47, respectively). Most outbreaks from Italy were reported in 2011-2013 and 2015 Germany and Italy had the greatest number of LPAI H7 outbreaks across all years (n=17 and 30 respectively). Most outbreaks from Italy were reported in 2009-2011. Species affected by LPAI H5 and H7 were mostly chickens (n=15 and 34 respectively), ducks (n=17 and four respectively) and 'mixed' (n=16 and 20 respectively). Species affected by LPAI of undetermined H subtype were mostly turkeys (n=48), mixed species (n=25) and chickens (n=20). Regarding LPAI detection in wild birds between 2005 and 2015, there were 1159 records for wild birds with LPAI, of the H5 subtype (831), H7 subtype (216) or unreported subtype (112), from 20 EU member Member States. The majority of LPAI-positive birds were recorded from Sweden, Germany, and the Netherlands. The wild bird species in which LPAI was most frequently reported was the mallard. However, this species also was the most frequently sampled. Other species in which LPAI was frequently reported were gadwall, Eurasian wigeon, garganey, greylag goose, and greater white-fronted goose. Experimental infections in chickens, turkeys and mallards showed clear differences in replication kinetics and transmissibility of LPAI strains. Depending on LPAI-HPAI pair, the transmissibility of LPAI or HPAI in chickens was higher.

Avian influenza

“…The parameters were informed based on: (i) data from experimental and observational studies collected by the Consortium ((Duncan et al., ,b; data received as per procurement, Erasmus University Medical Centre, OC/EFSA/ALPHA2015/01, unpublished Gonzales; and data received as per procurement, coordinated by Linnaeus University SE) and Erasmus Medical Centre (NL), OC/EFSA/ALPHA 2015/01 supplemented with NP/EFSA/ALPHA/2015/04, unpublished) and the Working Group (WG) experts (see Appendix D), and (ii) EKE (semi‐formal and formal), performed using the Sheffield method. Parameters have been estimated by experts as probability distribution reflecting the uncertainty around the unknown true values (see Section C.6 in Appendix C).…”

“…Data have been extracted by the AI Consortium from the scientific literature (Duncan et al., ,b). A descriptive analysis of the data is provided in Section 3.5 and tables with transmission characteristics are included in Appendix E.…”

“…The objective was to describe the current understanding of the mechanisms that govern pathogenicity of AIV in poultry and to identify factors that might influence LP‐to‐HP mutation rates with respect to virus, environmental and host species‐specific aspects. Data have been extracted by the AI Consortium from the scientific literature (Richard et al., ) and several databases have been used (GISAID, ; data collected by the Consortium as reported by Duncan et al., ,b).…”

“…The concentration of LPAIVs shed by mallards and falcons experimentally infected with LPAI H5N2 and H7N2, respectively, is given in Table . Further scientific evidence is provided in the systematic literature review performed by the AI consortium, identifying and synthesising the evidence on risk factors of HPAI and LPAI introductions into European poultry holdings (Duncan et al., ).…”