A Fatal Case of Puumala Virus Infection with Pulmonary and Renal Syndrome in Moscow Region, Russia.

Hemorrhagic fever with renal syndrome (HFRS) is the most common zoonotic disease in Russia, with about a 98% abundance of Puumala virus in all HFRS cases. We report clinical manifestations and genomic characteristics of the Puumala virus strain that caused an unconventional course of HFRS with sudden death. The patient was admitted to the hospital on the third day from fever onset with hyperthermia, cough, shortness of breath, and severe weakness, and died 28 h after hospitalization despite intensive care. Further analyses of autopsy samples led to Puumala virus detection. The viral genome was sequenced, followed by phylogenetic and similarity plot analyses. The genomic sequences of three viral segments were identified as endemic for the Moscow region strain. Phylogenetic and similarity plot analysis revealed the reassortant origin of the strain via M segment exchange. This finding increases the explored molecular diversity of Puumala virus in the Central Federal District and underscores the need for heightened awareness of HFRS manifestations that deviate from regular clinical presentation.