Rare viral disease: three people died from Bornavirus
The Bornavirus is a pathogen that had previously only been observed in animals. But now there is evidence that the brain inflammation that killed three people was caused by the dangerous virus. However, experts assume very rare individual cases.
First confirmed Bornavirus evidence in humans
In Germany, three patients died from the consequences of a viral disease that, according to experts, has so far only been observed in animals. Those affected had an inflammation of the brain, which was most likely caused by the classic Bornavirus. The Robert Koch Institute (RKI) in Berlin and the head of the Institute for Virus Diagnostics at the Friedrich-Loeffler-Institut (FLI) in Greifswald, Martin Beer, assume that this is the first confirmed Bornavirus evidence in humans at all .
Severe inflammation of the brain
The RKI recently reported on the cases in the “Epidemiological Bulletin” (10/2018).
There it is said that studies by the FLI in cooperation with the university clinics in Regensburg, Munich and Leipzig, among others, for the first time the classic Borna disease virus 1, BoDV-1; species Mammalian 1 Bornavirus) as a probable trigger of severe inflammation of the brain (encephalitis ) identified in humans.
"The diseases occurred in three recipients of donor organs from the same postmortem organ donor and two of the transplanted patients died later," write the experts.
"The new test results confirm the first confirmed BoDV-1 diseases in humans."
However, the participating institutions and the RKI currently agree that "the BoDV-1 diseases of the organ recipients described above are a very rare individual case."
But: “Regardless of what happens during the transplantation, there is evidence of a fatal infection with the classic Bornavirus with the symptoms of massive encephalitis in another patient. A similar case is currently being clarified. "
Virus differs from the pathogen that was identified in 2015
At the end of 2016, the researchers from the FLI, the federal research institute for animal health, were brought in by the university hospitals where the patients had been treated because the cause of the brain inflammation could not be found using standard diagnostics.
In 2015, the FLI was involved in the elucidation of three unclear brain inflammations. At that time, they found a new Bornavirus (Bornavirus der Hörnchen, VSBV-1) from deceased Bunthörnchen breeders in Saxony-Anhalt, which was transmitted by the animals.
This time, thanks to special analysis methods, the researchers discovered the classic BoDV-1, known from horses and sheep, which, according to the RKI, differs from the virus detected in 2015.
"So far, there has been no search for brain inflammation because there was no evidence that it could matter," said Martin Beer of the FLI in a message from the dpa news agency.
"Based on the current, new findings, should be examined for unclear human encephalitis diseases for BoDV-1," writes the RKI.
Detect Bornavirus infections at an early stage
As Hartmut Hengel, President of the Society for Virology and Virologist at the University of Freiburg, said according to dpa, the aim now is to develop new detection methods so that Bornavirus infections can be detected at an early or chronic stage.
In the case of the organ donor, such an infection must have been present so that the person appeared healthy and organs could be transplanted.
However, Hengel does not currently consider further arrangements to safeguard organ donation to be possible - and, given the apparent rarity of the virus, it is not necessary either.
"We still do not have any suitable tools to preventively test organ donors," says the professor, according to dpa.
In addition, it is not clear whether previous illnesses may play a role in the cases now documented.
Diseased animals mostly die from the consequences of infection
Infections with the Bornavirus in horses have been known for over 100 years - with brain inflammation as a possible consequence.
Diseased animals show movement disorders and behavioral problems. They often die from the consequences.
According to experts, it has not been finally clarified how the animals become infected, but it is known that the pathogen in Germany can multiply in shrews and can be eliminated by them. The path to people is then unclear.
According to the RKI, the virus, which is named after the place Borna near Leipzig, generally occurs rarely.
Controversy over the dangerousness of the virus
There has been scientific controversy in the past about the virus and its dangerousness. Research at the RKI on possible Bornavirus infections in humans, which began in the early 1990s, was discontinued in 2005.
At the time, it was said that despite years of efforts, no reliable evidence of a risk to humans had been found.
Alleged Bornavirus evidence in human samples was later traced back to contamination in the laboratory.
The topic had also received a lot of attention because some of the scientists described the Bornavirus as a factor in the development of diseases such as depression and schizophrenia.
However, Martin Beer from FLI emphasized: “You have to clearly separate the current individual cases from the discussions of the past 20 years and the investigations back then. We now see very clear symptoms, we have deaths and very large amounts of the virus genome can be found in the samples of the deceased patients. ”
Researchers from several German institutions now want to investigate open questions about Bornaviruses - such as infection routes and risk areas - in a federally funded consortium ("ZooBoCo"). (ad)