Only 2018 was the fatal pathogen detected in humans. Now it turns out: In this country far more people have died from infection with so-called Borna viruses in recent years than previously known.
The virus was detected in Bavaria in brain samples from deceased patients, researchers from the Friedrich Loeffler Institute (FLI) and the University of Regensburg report in the specialist journal “The Lancet Infectious Diseases”.
In total, at least died since 1995 ) People proven to have brain inflammation. The scientists date the latest known Borna case to the end 2019. An eleven-year-old girl died in the process. To what extent the virus could be behind brain inflammation with an unknown cause is so far unclear.
Some infected infected through organ donation
The scientists had brain samples from 56 Patients from Bavaria were examined who had been diagnosed with brain inflammation between 1999 and 2019. No reason was found for 28, nine of these sufferers had died. Borna Disease Virus 1 (BoDV-1) was detected in seven of these nine people.
Regardless, there were two other confirmed infections. All cases occurred in Bavaria and were diagnosed at the Regensburg University Hospital, in Erlangen or in the Munich area, said Martin Beer, Head of the Institute for Virus Diagnostics at the FLI.
There were already five further detection reports known from the years 2018 and 2019. Among other things, three people were infected with the fatal disease by donating an organ because they had received a kidney or the liver of an infected person from Bavaria. Only one of them survived the disease, but with serious health consequences.
The only reservoir for the virus: the Feldspitzmaus
That about horses and sheep infected with Borna disease and can die from it has long been known. BoDV-1 occurs in Germany in Bavaria, Thuringia, Saxony-Anhalt and adjacent parts of neighboring federal states. Cases of Borna disease in horses, sheep and other farm animals also regularly occur in Austria, Switzerland and Liechtenstein. “It's an old illness, but you always looked wrong,” said Beer.
The only known reservoir of the pathogen is the shrew ( Crocidura leucodon ), in which the infection does not cause any severe symptoms. The mice excrete the virus in urine, faeces and saliva – this can then infect other animals and, in rare cases, humans.
Infection from person to person or from horse to person is naturally excluded, Beer explained. He speaks of so-called dead end hosts who carry the virus but do not spread it further. The infection is likely to be fatal very often in both farm animals and humans.
Most of those affected had contact with animals
How exactly the patients looked Bavaria, who became infected with the virus regardless of organ donation, is unclear, according to Beers. Many would have had close contact with cats – who may have caught a shrew and brought it home.
But that's just a hypothesis. According to the report in the journal, most of the 14 sufferers had contact with animals, lived in rural areas, worked in agriculture or had been involved in outdoor activities.
Beer and his colleagues call on doctors in Borna areas to have patients with severe brain inflammation tested for the virus if the cause of the disease is unclear. So far, there is no obligation to register for the disease – however, according to Beers, this should change in March.
There is no reason to panic, he emphasized. “I still count on individual cases. The risk for the individual – even in Bavaria – is very low.” There is currently no special therapy for the disease.
First symptoms: headache, fever, feeling sick
According to the “Ärzteblatt”, the few infections known to date – with the exception of younger children – affect all age groups and both genders. According to the Robert Koch Institute (RKI) in Berlin, many of the well-known patients initially suffered from headaches, fever and a general feeling of illness. This is followed by neurological symptoms such as confusion, behavioral problems and speech and gait disorders, and often coma and death within days or a few weeks.
In addition to BoDV-1 there is also the Variegated Squirrel Bornavirus 1 ( VSBV-1). This pathogen, which occurs in colored squirrels, is also transferable to humans, as has been known for some years. It was demonstrated for the first time in three hobby breeders from Saxony-Anhalt who had symptoms in the years 2011 to 2013 Brain infections were treated in clinics and died. It was shown that representatives of the Bornavirus family can also infect humans, it said when the results were published in the year 2015. (AP)