Outbreaks of Highly Pathogenic Avian Influenza (HPAI) are common today all across the world. The occurrence of the virus in wild and domestic birds is neither limited to a certain avian species or to any species for that matter. The global poultry community needs to find a way to live with the constant threat and reoccurring out-breaks. This paper sheds light on two major outbreaks in the USA in 2015 and in Germany in 2017. For both countries, these outbreaks were the largest up until then and were therefor equally challenging for authorities and the poultry industry. The dissertation analyses the spatial development of the outbreaks and includes an economic impact assessment for each country. Locally applied virus mitigation methods are compared with regard to effectiveness and cost efficiency. The quantitative analysis is backed up by expert interviews in both the USA and Germany. The interviews validate quantitative results and improve the understanding of the industry and its key stakeholder. The statements of the interviews were categorized and further analyzed using inductive category formation. Through quantification of statements in each category, comparatability between results of both countries is achieved. Results show a clear and distinct spatial development of both outbreaks around clearly defined epicentres in areas with exceptionally high densities of poultry production. After a first line of small outbreaks, the virus spread wildly affecting a majority of operations in the areas. The devastating progression of the virus can be linked to ineffective, faulty or slow mitigation measures. In Germany, efficient mitigation processes were in place before the outbreak, yet small mistakes led to a cascade of ensuing outbreaks nonetheless. Overall, the poultry industry of the USA was affected more severely. Mitigation processes in Germany used financial resources more efficiently and indemnification payments for farmers were quicker and higher. At the same time, mitigation efforts were relatively cheaper in the USA. The secondary industry was impacted more severely in the USA due to longer idle production times. Experts supported these findings and demanded more commitement to biosecurity in the future.