Serological and molecular evidence showed that a German female student became infected by Puumala hantavirus during mice trapping efforts in Finland. The incubation period before exhibiting clinical signs of nephropathia epidemica was as long as 6 weeks. Phylogenetic analysis of PUUV nucleic acid sequences amplified from the patient demonstrate that she was infected by the PUUV strain circulating at the place of her occupational exposure in Finland.