Challenges and lessons learned from preliminary modeling of with-in herd transmission of highly pathogenic avian influenza H ₅ N ₁ in dairy cattle

The emergence of highly pathogenic avian influenza A H ₅ N ₁ in dairy cattle raises many questions related to animal health and changes to the risk of an epidemic in humans. We synthesized information currently published to fit a compartment model of H ₅ N ₁ transmission within a dairy herd. An accompanying web application allows users to run simulations for specific outbreak scenarios. We estimated R ₀ near 1.2 with a short duration of infectiousness and fast time course of an epidemic within a farm, which we discuss in the context of possible on-farm control strategies. The web application allows users to simulate consequences of an epidemic using herd-specific information, a tool we propose will help inform stakeholders about potential consequences of uncontrolled H ₅ N ₁ spread. Our modeling work has identified several key information gaps that would strengthen our understanding and control of this emerging infectious disease.