The cause is officially unclear but The Netherlands are part of an important route for migrating birds. The Wadden Sea is an official World Heritage Site and millions of birds rest and feed there an route to and from the chilly northern Russian plains and the warmer climes of southern Europe or the sub-Sahara.
Because Low Pathogenic Avian Influenza (LPAI) can easily mutate into Highly Pathogenic Avian Influenza (HPAI), the authorities rightfully decided to cull all chickens in the affected poultry farms.
But the Dutch will remain vigilant because these outbreaks of Influenza A are an accident waiting to happen. Consumers increasingly want to have meat from free-range chickens and pigs on their menu. Both are excellent mixing vessels for a new and potentially lethal Influenza virus.