Hantaviruses are found in small mammals such as z.B. Mice before. Infection occurs through bites, contact with animals, and inhalation of contaminated dust. As a preventive measure, it is recommended to avoid contact with rodents and their excrement.
Pathogen and transmission
Hantaviruses are among the causative agents of viral hemorrhagic fevers. They are named after the Korean border river Hantaan, where during the Korean War (1950-1953) more than 3000 soldiers fell seriously ill after an infection. Transmission to humans occurs through infected rodents (z. B. mice or rats), which excrete the virus through saliva, urine and feces. Infection can occur through rodent bites, contact with rodents or their droppings, and inhalation of contaminated dust.
There are many different types of hantaviruses, which differ in terms of distribution and clinical picture. Human-to-human transmission has only been described for one extremely rare virus type.
Disease pattern
The infection goes unnoticed in the majority of cases. If symptoms occur, it leads to various severe clinical pictures, depending on the type of virus, up to febrile courses with a massive bleeding tendency (hemorrhagic fever). The illness usually begins with a sudden onset of high fever that lasts for 3 to 4 days. It is accompanied by non-specific, flu-like symptoms such as headache, abdominal pain and muscle pain.
The period between infection and the first clinical symptoms is variable and is usually 1 to 5 weeks. Effective drugs against hantaviruses do not exist, therapy is limited to alleviation of symptoms.
Hantavirus types found in Europe and Asia cause hemorrhagic fever with renal syndrome (HFRS), which can lead to renal dysfunction and even acute renal failure. 1 to 15 % of HFRS cases are fatal. The types existing in North and South America cause hemorrhagic fever with pulmonary syndrome (HCPS or HPS), pulmonary edema and acute respiratory failure as possible complications. Up to 50 % of these cases end with the death of the affected persons.
Prevalence and incidence
Hantaviruses occur worldwide. Since 2000, around 3000 cases have been registered annually in Europe, with Switzerland hardly affected at all. Germany, Finland, Austria and Slovenia have the highest number of cases in Europe. In Germany, annual numbers vary widely. On average, the disease is registered there in about 230 people. In 2012, however, there was a major outbreak with about 3000 people affected. Severe courses of the disease with life-threatening bleeding are extremely rare in Europe.
Prevention
There is no vaccination against hantaviruses. The only prevention is to avoid contact with rodents and their excreta.