Commonground
Senior Moderator
16 Feb 2026
New research from the Royal Veterinary College has uncovered how the way chickens are produced, traded and transported in northern Viet Nam can contribute to the spread of avian influenza viruses. As chickens move through farms, markets and slaughter points, they mix at multiple stages, creating hotspots for viral transmission. These findings highlight that in order to protect both human and animal health, surveillance and control strategies must cover the entire poultry supply chain rather than focusing on individual farms or markets.
With chickens becoming the most widely produced land-based animals globally, avian influenza poses a serious threat to poultry production, public health and food security. Rapid expansion of chicken production in South and Southeast Asia has created increased opportunities for avian influenza viruses to emerge and evolve, including strains that can infect humans.
While live bird markets are well-known hotspots for transmission, much less is understood about the wider production and distribution system. In Viet Nam, practices such as trading live chickens and slaughtering birds at the point of sale further increases the risk of human exposure. However, there is limited data linking farms, distribution facilities and points of sale which has left gaps in understanding where infection risk is highest – highlighting the need for surveillance across the entire poultry network.
This study was conducted by the RVC and with project partners in Viet Nam, France and Hong Kong to carry out a cross-sectional investigation of chicken production and distribution systems in northern Viet Nam. The researchers collected 1,682 samples across 50 farms and 52 distribution facilities in four provinces, including retail and wholesale markets, small-scale slaughter points and industrial slaughterhouses. To understand how chickens moved through the system, the researchers also interviewed farmers, traders and facility operators. This data was used to trace chicken movements and analyse the poultry supply chain as a connected network, allowing researchers to identify where chickens from different sources were most likely to mix, as well as testing for the presence of avian influenza viruses.
The study revealed clear differences in the presence of avian influenza viruses across the poultry production and distribution system. Two virus types were examined: A(H5N1), which is a highly pathogenic virus associated with severe disease; and A(H9N2), a low pathogenic virus which typically causes less severe disease in chickens. Both virus types can harm poultry and potentially infect humans directly or can combine with other influenza viruses to form new strains. Only one chicken tested positive for A(H5N1), whereas A(H9N2) was detected in 11% of all sampled chickens, with higher prevalence in distribution facilities than on farms.
continued: https://farming.co.uk/news/royal-ve...uenza-risks-in-viet-nams-chicken-supply-chain
New research from the Royal Veterinary College has uncovered how the way chickens are produced, traded and transported in northern Viet Nam can contribute to the spread of avian influenza viruses. As chickens move through farms, markets and slaughter points, they mix at multiple stages, creating hotspots for viral transmission. These findings highlight that in order to protect both human and animal health, surveillance and control strategies must cover the entire poultry supply chain rather than focusing on individual farms or markets.
With chickens becoming the most widely produced land-based animals globally, avian influenza poses a serious threat to poultry production, public health and food security. Rapid expansion of chicken production in South and Southeast Asia has created increased opportunities for avian influenza viruses to emerge and evolve, including strains that can infect humans.
While live bird markets are well-known hotspots for transmission, much less is understood about the wider production and distribution system. In Viet Nam, practices such as trading live chickens and slaughtering birds at the point of sale further increases the risk of human exposure. However, there is limited data linking farms, distribution facilities and points of sale which has left gaps in understanding where infection risk is highest – highlighting the need for surveillance across the entire poultry network.
This study was conducted by the RVC and with project partners in Viet Nam, France and Hong Kong to carry out a cross-sectional investigation of chicken production and distribution systems in northern Viet Nam. The researchers collected 1,682 samples across 50 farms and 52 distribution facilities in four provinces, including retail and wholesale markets, small-scale slaughter points and industrial slaughterhouses. To understand how chickens moved through the system, the researchers also interviewed farmers, traders and facility operators. This data was used to trace chicken movements and analyse the poultry supply chain as a connected network, allowing researchers to identify where chickens from different sources were most likely to mix, as well as testing for the presence of avian influenza viruses.
The study revealed clear differences in the presence of avian influenza viruses across the poultry production and distribution system. Two virus types were examined: A(H5N1), which is a highly pathogenic virus associated with severe disease; and A(H9N2), a low pathogenic virus which typically causes less severe disease in chickens. Both virus types can harm poultry and potentially infect humans directly or can combine with other influenza viruses to form new strains. Only one chicken tested positive for A(H5N1), whereas A(H9N2) was detected in 11% of all sampled chickens, with higher prevalence in distribution facilities than on farms.
continued: https://farming.co.uk/news/royal-ve...uenza-risks-in-viet-nams-chicken-supply-chain