Latest Outbreaks of Bornavirus in Bavaria: Essential Q&A
- Author: Solvejg Hoffmann
- Approx Read Time: 3 minutes
Hazardous Bornavirus surfacing in Upper Bavaria: Answers to Crucial Inquiries - Potentially Hazardous Bornavirus Surfaces in Upper Bavaria: Primary Inquiries and Responses
There has been a recent surge of the extremely rare but potentially lethal Borna virus infection cases in Bavaria, with two individuals from Pfaffenhofen confirmed infected. Another patient is currently receiving treatment, as per a spokesperson for the Pfaffenhofen an der Ilm district administration office.
Just last June 2022, a case of Bornavirus was detected in an individual from the western Landkreis Mühldorf am Inn in Bavaria. The virus was detected in a 58-year-old woman from the Landkreis Anhalt-Bitterfeld in Saxony-Anhalt at the end of 2021. Known instances of the virus in humans have been isolated in Germany in previous years.
So far, roughly 45 cases of BoDV-1 disease have been verified in humans, with around ten cases reported annually for the whole of Germany, predominantly from Bavaria.
What's the Gist of Bornavirus?
The Borna Disease Virus 1, often referred to as BoDV-1, has been linked with Borna's disease for quite some time. Initially, this virus was only observed in farm animals such as horses and sheep primarily in Central Europe. BoDV-1 was first identified in humans in 2018, as the source of severe brain inflammation.
The disease became notifiable since 2020. Since then, up to six acute cases of BoDV-1 encephalitis have been reported annually to the Robert Koch Institute (RKI), with the majority of these cases in Bavaria, as stated by the LGL.
BoDV-1 does not resemble the closely related Bunthornchen-Bornavirus (Variegated squirrel bornavirus 1, VSBV-1) directly. The virus that affects squirrels has been known to be transmissible to humans for several years. It was first found in three hobby breeders from Saxony-Anhalt who experienced symptoms of brain inflammation and subsequently passed away in the years 2011 to 2013.
Where's BoDV-1 Prevalent?
According to the Robert Koch Institute, field shrews, scientifically known as Crocidura leucodon, have been identified as the natural reservoir of BoDV-1 in Central and Southeast Europe. These shrews are thought to spread the virus via saliva, urine, and feces.
Reported endemic areas for BoDV-1 in Germany are mainly Bavaria, Thuringia, and Saxony-Anhalt, as well as adjacent regions of these federal states. The virus has also been detected in animals in Switzerland (particularly the Alpine Rhine), Liechtenstein, and Austria (notably Vorarlberg and Upper Austria).
How Does Infection Occur?
The specific transmission routes for the Bornavirus are still not fully understood in the scientific community. Numerous possible transmission methods are considered, for instance direct contact with the virus through contaminated food, water, or soil, or contact with infected field mice, their saliva, urine, or feces while grazing.
In terms of human transmission, several scenarios are plausible. It is most likely that humans contract the pathogen via contact with the excretions of field mice or direct animal contact. To stay safe, the LGL advises avoiding contact with field mice and their excretions and discourages handling live or dead animals with bare hands.
Potential means of infection could also include contaminated food or water, inhaling the virus through dust, as well as other animals, such as domestic cats, that hunt field mice, potentially playing a significant role in the infection chain. Human-to-human transmission is thought to be quite unlikely according to the Robert Koch Institute, while other animals besides field mice are not believed to be infectious to either animals or humans.
What's the Risk of Infection in Germany?
Specialists estimate that anywhere from two to six acute cases of Bornavirus infection may occur in humans in Germany each year. While the infection risk is primarily associated with contact with field mice, such occasions may be rare and challenging to prevent at the current level of knowledge.
A potentially higher infection risk exists for outdoor activities that may result in contact with field mice or their excrement—for example, gardening, agricultural and forestry work, construction work, and cleaning buildings where field mice have previously been present. In the years 2018 and 2019, three individuals were infected with the fatal disease via an organ transplant after receiving a kidney or liver from an infected individual in Bavaria.
What Typical Symptoms Does an Infection Display?
The most common early symptoms of the disease are headaches and fever. Infected patients often experience neurological symptoms like behavioral abnormalities, speech and gait disorders, and coma within days or weeks.
Is Bornavirus Harmful to Humans?
The Borna Disease Virus 1 can lead to severe brain inflammation in humans. So far, all reported cases have been fatal for humans, except for one. Currently, there is no specific treatment for Bornavirus infections, and care consists primarily of supportive measures with intensive medical attention.
The Borna Disease Virus 1 (BoDV-1) is closely linked with medical-conditions such as encephalitis, a severe brain inflammation, which became notifiable in 2020. This virus shares a natural reservoir, mainly found in field shrews, with the closely related Bunthornchen-Bornavirus that has been known to be transmissible to humans.
In terms of health and wellness, it's essential to understand that the BoDV-1 infection risk is associated with contact with field mice, and prevention can be challenging due to the limited understanding of specific transmission routes. The virus can lead to symptoms like headaches, fever, behavioral abnormalities, speech and gait disorders, and even coma in humans, with all reported cases so far being fatal, except for one.
