Avian Influenza in the Netherlands, 2018
Nancy Beerens, NRL meeting, Italy, June 2019
Wageningen BioVeterinaryResearch
Detections of HPAI H5N6 in 2017-2018
2
Location farm species date
Biddinghuizen Duck 7-12-2017
Oldekerk Chicken 25-2-2018
Kamperveen Duck 13-3-2018
Biddinghuizen various 15-12-2017
Rhoon various 20-1-2018
No virus transmission between farms
Full genome sequences of viruses
isolated from the 3 commercial poultry
farms were compared
Large number of genetic differences
Relatively long time between infections
No epidemiological links identified
Separate introductions from wild birds
3
location host date day km nt code
Biddinghuizen duck 7-12-2017 - - - BH
Oldekerk chicken 25-2-2018 80 97 47 OK
Kamperveen duck 13-3-2018 96 12 49 KV
Detection of H5N6 in wild birds
4
location date family species #1 code2
Elburg 9-12-2017 Anatidae mute swan - Cygnus olor 1 wb1
Hulshorst 9-12-2017 Anatidae tufted duck -Aythya fuligula 1 wb2
Hulshorst 9-12-2017 Anatidae mute swan - Cygnus olor 5 wb3
Harderwijk 14-12-2017 Anatidae mute swan - Cygnus olor 1 wb4
Elburg 19-12-2017 Anatidae mute swan - Cygnus olor 1 wb5
Enkhuizen 21-02-2018 Anatidae greater scaup - Aythya marila 1 wb6
Westernieland 1-03-2018 Falconidae peregrine falcon - Falco peregrinus 1 wb7
Stavernisse 14-03-2018 Accipitridae buzzard - Buteo buteo 1 wb8
Zandfoort 15-03-2018 Accipitridae buzzard - Buteo buteo 1 wb9
Eemmeer 24-08-2018 Anatidae mallard - Anas platyrhynchos 1 wb10
Eemmeer 31-08-2018 Accipitridae Eurasian marsh harrier - Circus aeruginosus 1 wb11
Genetic analysis of poultry and wild bird viruses
5
Commercial farms
Hobby farms
Wild birds NL
Wild birds EU
Biddinghuizen
cluster
Median-Joining-Network Analysis was performed for all viruses
Biddinghuizen in cluster of viruses derived from a common ancestor
Kamperveen and Oldekerk are more distantly related
Detections of H5N6 in August 2018
H5N6 viruses detected between 12/2017 and 3/2018
In previous epidemics, virus was not observed after winter
Wild birds migrate to breeding grounds in March-April
But on 24 August 2018: positive mallard, Eemmeer
Several days later, bird of prey from same area
Question:
A novel introduction by wild bird migration?
Or virus persisting during summer?
6
H5N6 detections in late August 2018
7
Location Eemmeer
Central Lake area
Near Biddinghuizen
First outbreak, dec 2017
H5N6 is a reassortant of H5N8 2016
H5N6 is a reassortant of H5N8 Group B
Contains novel NA and PB2 segments,
derived from Eurasian LPAI viruses
Molecular clock analysis: reassortment
events likely occurred in 2015–2016
This was before the virus was introduced
into the Netherlands (dec 2017)
Late H5N6 virus has similar genetic
constitution
8
H5N8 Eurasia 2016, PA II
H5N6 Netherlands
PB2PB1PA
HANPNA
NSMP
MP
PB2PB1PA
HANPNA
NS
Median-Joining-Network Analysis
9
Most likely the virus still circulated in local wild birdpopulations
First time this is observed: higher risk for HPAI introduction all year round?
Eemmeer: common ancestorwith Biddinghuizen cluster
53 nt differences in 9 months
Eemmeer
Dead wild bird surveillance
10
VirusClade
2.3.4.4wild bird mortality
positive
# tested # species
H5N8 2014 Group A None 0 0
H5N8 2016 Group B Massive 84 17
H5N6 2017 Group B Limited 15 7
Eurasian wigeon
>3000 deaths
Tufted duck
>6000 deaths
Mute Swan Bird of Prey
Pathogenicity of HPAI H5N6
Wild bird mortality related to H5N6 lower than for H5N8 2017
Pathogenicity of the two viruses for ducks is similar:
● IVPI is not natural way of infection
● Pekin ducks not a model for all wild bird species
Lower prevalence of the virus in wild bird population
Protective immunity in wild bird population (H5N8 2016)
11
VirusClade
2.3.4.4wild bird mortality
IVPI chicken
IVPI duck
H5N8 2014 Group A None 3.00 1.87
H5N8 2016 Group B Massive 3.00 2.99
H5N6 2017 Group B Limited 2.99 3.00
Detection of LPAI viruses in 2018
No detections in commercial poultry
captive birds – Swan: H5N3 LP
wild birds – Mallard: H8N4
Eurasian Teal: H3N8
12
Results of passive surveillance program
13
Jaar Maand Plaats Subtype
2018 2 Vaassen HxNx
2018 3 Neerkant H5Nx
2018 3 Hiaure H2N5
2018 3 Den Bommel H5Nx
2018 3 Maarsbergen H5N3
2018 4 Sterksel H9N7
2018 5 Steenwijkerwold H9N3
2018 6 Den Bommel H6N8
2018 6 Odoornerveen H7N3
2018 6 Winterswijk HxNx
2018 7 Boxmeer HxNx
2018 7 Tzummarum H2N5
2018 7 Idsegahuizum H10N7
2018 8 Aalten HxN3
2018 8 Donkerbroek HxN7
2018 8 Hierden HxN2
2018 9 Zuidwolde HxNx
2018 9 Overberg HxNx
2018 9 Tubbergen HxNx
2018 10 Nieuweroord HxNx
2018 10 Oosterwolde Fr H4Nx
2018 11 Radewijk HxNx
2018 12 Groesbeek H10Nx
2018 12 Elsloo Fr H6N2
2018 12 Lemelerveld H5N3 LP
2018 12 Milheeze H9N2
2018 12 Stadskanaal H6Nx
2018 12 Sint Philipsland H3N8
2018 12 Veeningen H5Nx LP
2018 12 Veeningen H5N3 LP
2018 12 Witteveen H6N8
No detections of H3N1
in 2018/2019
Thanks to:
14
René Heutink
Sylvia Pritz-Verschuren
Frank Harders
Alex Bossers
Guus Koch
Saskia Bergervoet
Evelien Germeraad
* Beerens et al. TransboundEmerg Dis 2019