Puumala virus

Puumala virus is a species of Orthohantavirus that is primarily responsible for causing a mild form of hemorrhagic fever with renal syndrome (HFRS) known as nephropathia epidemica. This virus is endemic to Europe and is transmitted to humans through contact with the excreta of infected rodents, particularly the bank vole (Myodes glareolus).

Virology

Puumala virus is a member of the Hantaviridae family, which is part of the order Bunyavirales. It is an enveloped virus with a negative-sense, single-stranded RNA genome. The genome is segmented into three parts: the small (S), medium (M), and large (L) segments, which encode the nucleocapsid protein, glycoproteins (Gn and Gc), and the RNA-dependent RNA polymerase, respectively.

Transmission

The primary reservoir host of Puumala virus is the bank vole. Humans typically become infected through inhalation of aerosolized particles from rodent urine, droppings, or nesting materials. Direct contact with rodents or their excreta can also lead to transmission. Human-to-human transmission is extremely rare.

Clinical Manifestations

Infection with Puumala virus leads to nephropathia epidemica, a milder form of HFRS. Symptoms typically include fever, headache, back pain, abdominal pain, and renal dysfunction. The disease is usually self-limiting, but in some cases, it can lead to acute kidney injury requiring hospitalization.

Diagnosis

Diagnosis of Puumala virus infection is primarily based on serological tests that detect specific antibodies (IgM and IgG) against the virus. Molecular techniques such as RT-PCR can also be used to detect viral RNA in blood or tissue samples.

Treatment

There is no specific antiviral treatment for Puumala virus infection. Management is primarily supportive, focusing on maintaining fluid and electrolyte balance and monitoring renal function. In severe cases, dialysis may be required.

Prevention

Preventive measures include reducing exposure to rodent habitats, particularly in endemic areas. This can be achieved by sealing homes to prevent rodent entry, maintaining cleanliness to deter rodent infestation, and using protective equipment when cleaning areas contaminated with rodent excreta.

Epidemiology

Puumala virus is predominantly found in Northern and Central Europe, with the highest incidence in Finland, Sweden, and Russia. The incidence of nephropathia epidemica varies seasonally and is influenced by the population dynamics of the bank vole.

Also see

• Hantavirus
• Hemorrhagic fever with renal syndrome
• Orthohantavirus
• Bank vole