# Avian Influenza A(H9N2) Virus Transmission across Chicken Production and Distribution Networks, Vietnam

## TL;DR

The study found that the H9N2 avian flu spreads more in chicken distribution centers than on farms in Vietnam, suggesting the need for better control measures across the whole poultry supply chain.

## Contribution

The study reveals extensive viral mixing in chicken production and distribution networks, emphasizing the importance of network-wide risk mitigation.

## Key findings

- H9N2 prevalence was higher in distribution facilities compared to farms.
- Phylogenetic analysis showed significant viral mixing across the chicken supply chain.
- Facility type influenced H9N2 prevalence patterns.

## Abstract

In northern Vietnam, during March 2021–March 2022, prevalence of influenza A(H9N2) in chickens was higher in distribution facilities than on farms and varied between facility types. Phylogenetic analysis indicated extensive viral mixing along networks of chicken production and distribution, highlighting a need for risk mitigation across the entire network.