Isolation of hemorrhagic fever with renal syndrome (HFRS) virus from a tumor specimen in a rat.

A strain of hemorrhagic fever with renal syndrome (HFRS) virus was isolated in a cell culture from a tumor specimen in a rat kept in a medical institution in which there was a case of HFRS. Positive immunofluorescent reaction with sera from HFRS patients was recognized at the second passage and the number of cells containing antigen increased in the third passage. This virus, named B-1 strain, was identified as the HFRS virus by immunofluorescent tests with sera from patients.