In 2006 he won the national title over all three distances and, in May, beat a top-class international field at Duisburg. Injury prevented him from appearing at the European championships, but he was determined not to miss the 2006 World Championships, held in his hometown of Szeged. He recovered in time to take the C-1 1000 m bronze medal behind surprise winner Everardo Cristóbal of Mexico and Germany's Andreas Dittmer. Vadja won the gold medal in the same event at the following world championships in Duisburg.