Risk mapping of highly pathogenic avian influenza H5 during 2012–2017 in Taiwan with spatial bayesian modelling: Implications for surveillance and control policies

In October 2020, a highly pathogenic avian influenza (HPAI) subtype H5N8 virus was identified from a fecal sample of a wild mandarin duck (Aix galericulata) in South Korea. We sequenced all eight genome segments of the virus, designated as A/Mandarin duck/Korea/K20-551-4/2020(H5N8), and conducted genetic characterization and comparative phylogenetic analysis to track its origin. Genome sequencing and phylogenetic analysis show that the hemagglutinin gene belongs to H5 clade 2.3.4.4 subgroup B. All genes share high levels of nucleotide identity with H5N8 HPAI viruses identified from Europe during early 2020. Enhanced active surveillance in wild and domestic birds is needed to monitor the introduction and spread of HPAI via wild birds and to inform the design of improved prevention and control strategies.

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1438Dynamics of inter-farm transmission of highly pathogenic avian influenza integrating vehicle movements and phylogenetic information

International Journal of Epidemiology ◽

10.1093/ije/dyab168.736 ◽

2021 ◽

Vol 50 (Supplement_1) ◽

Author(s):

Dae-sung Yoo ◽

Chun Byung Chul

Keyword(s):

Network Analysis ◽

Avian Influenza ◽

Highly Pathogenic Avian Influenza ◽

Control Strategies ◽

Poultry Production ◽

Movement Restriction ◽

Phylogenetic Information ◽

Highly Pathogenic ◽

Pathogenic Avian Influenza ◽

And Control

Abstract Background Highly pathogenic avian influenza (HPAI), a zoonotic infectious disease, has been considered a severe threat to public health. The fundamental prevention and control strategy against HPAI includes minimizing the outbreaks of poultry holdings where the virus primarily spreads through animal trade and poultry production associated vehicle movement (PPVM). However, very few attempts have been made to elucidate the association between PPVM and HPAI transmission compared to studies on poultry trade. Therefore, our study aimed to elucidate the role of PPVM on HPAI transmission. Methods We performed network analysis using PPVM data based on a global positioning system (GPS), with phylogenetic information of the HPAI virus for reliable estimation. Moreover, the contribution of PPVM to HPAI infection was estimated by Bayesian inference. Results The network analysis revealed that the connection via PPVM between the same genetic group of infected premises (IPs) was more prevalent than that of different genotype IPs. Moreover, the similarity of farm poultry species and the overlapped integrators between inter-linked IPs was associated with potential transmission route formation. Additionally, the contribution of PPVM among phylogenetically clustered IPs was estimated to have 28.25% of HPAI infections in IPs on average. Conclusions HPAI control strategies including targeted movement restriction and standstill should be established against the HPAI transmission via PPVM. Key messages This is a solid and novel study depicting the need for combining epidemiological analysis with data regarding molecular epidemiology of pathogens.

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