Puumala Virus and Nephropathia Epidemica: A Review of Virology, Transmission Dynamics, and Clinical Management

Puumala virus (PUUV), a member of the Hantavirus genus within the Bunyavirales order, is a significant zoonotic pathogen responsible for nephropathia epidemica (NE), a mild to moderate form of hemorrhagic fever with renal syndrome (HFRS). The virus is maintained in nature through a persistent, asymptomatic infection in its primary reservoir, the bank vole (Myodes glareolus). Human transmission occurs predominantly via the inhalation of aerosolized excreta from infected voles. PUUV is endemic across Northern, Central, and Eastern Europe, with incidence rates influenced by complex ecological dynamics, including a 3-4 year cycle in vole populations driven by climatic factors. Clinically, NE presents after a 2-8 week incubation period with an abrupt onset of high fever, headache, abdominal and back pain, and blurred vision, often accompanied by facial flushing, ocular redness, and a petechial rash. The hallmark of severe disease is acute kidney injury (AKI), which can progress to acute renal failure, hemodynamic instability, and vascular leakage. Diagnosis primarily relies on serological detection of PUUV-specific IgM and IgG antibodies, while molecular methods like RT-PCR are valuable for early detection and viral load quantification. Treatment remains largely supportive, focusing on meticulous fluid and electrolyte management; ribavirin has been used in severe cases, though its efficacy is not fully established. Prevention strategies center on public health education to minimize exposure to rodent habitats and the safe decontamination of potentially infected areas. This 14-page review provides a detailed synthesis of PUUV, encompassing its molecular biology, host-reservoir interactions, global epidemiology, pathogenesis, clinical presentation, diagnostic modalities, and current management approaches, highlighting its role as a model for understanding rodent-borne hantavirus diseases.