On 21 March 2008, the Austrian health authorities reported a cluster of measles cases in an anthroposophical school in Salzburg, the capital of one of Austria’s nine regions, through the Early Warning and Response System (EWRS). The EU Member States and the European Centre for Disease Prevention and Control (ECDC) were notified that about 40 out of 400 students from the affected school had contracted measles; two additional cases without an epidemiological link were also identified.