Between 31 December 2009 and 10 February 2010, 13 patients were infected by an identical hepatitis A virus strain not previously detected in the Netherlands. They had not been abroad and were widely distributed over the Netherlands. A case-control study including 12 cases and 44 controls identified semi-dried tomatoes in oil as the source of the outbreak (odds ratio: 20.0; 95% confidence interval: 1.5-274). The virus was not detected in any of 81 tested food samples. International trace-back is still ongoing.