Rare virus that causes nearly 100% death suddenly 're-emerges'

On June 9, German health authorities warned of a very rare case of Borna disease (BDV). The Frankfurter Rundschau newspaper reported that the case was a resident of Mühldorf am Inn, Bavaria, Germany. This case is notable because the Borna virus is very rare but has a very high mortality rate of up to 100%.

Rare neurological disease

According to the Bavarian State Office of Health and Food Safety, the Borna virus (BoDV-1) has been a pathogen in animals for more than 250 years. Borna virus originally only caused disease in animals, mainly horses, but in many cases it jumped to humans. In 2018, BoDV-1 was first identified as the cause of severe brain inflammation (encephalitis) in humans. Research on this disease is also quite meager.

Borna virus under an electron microscope.

For decades, the ability of Borna virus 1 (BoDV-1) to be transmitted from animals to humans has been the subject of expert debate. Previous studies have sought to link human infection with other mental disorders such as bipolar disorder or schizophrenia, but the results have been controversial.

A study published in the journal The Lancet Infectious Diseases in 2020 was highly appreciated for its detailed descriptions of people with the disease in Germany (January 1995 – August 2018). In which, 9 cases died from encephalitis. 7/9 people positive for Borna virus 1.

All 7 of these people had the onset of the disease with headache, fever, neurological symptoms such as unsteadiness, memory loss, convulsions, confusion, and gradual loss of consciousness. The patient fell into a coma after admission and died within 16 to 57 days.

From the investigated data, the authors concluded that the disease caused by Borna virus is relatively rare but has a high rate of leading to severe encephalitis, unexplained death.

The shrew is a host for the Borna virus. The virus can be spread when an animal or person comes in contact with the animal's feces, urine, or saliva.

There is no treatment

Borna virus disease is a deadly disease with neurological symptoms, affecting warm-blooded animals. Borna disease is very rare. The name Borna refers to the city of Borna, Germany, where an epidemic occurred in the late 1800s that affected many horsemen of the time.

To date, only a handful of human cases of BoDV-1 have been identified, occurring between 1996 and 2022. As of June 2022, the average number of confirmed cases is two. numbers. In particular, the case in Germany is the latest, showing that Borna has re-emerged.

In 2021, 7 people have Borna disease across Germany, 5 of them from Bavaria. First, the virus was detected in a cluster of cases involving an organ transplant recipient. Two of the transplant patients later died. One person survived but the disease left severe consequences.

Subsequently, other independent cases unrelated to this cluster were detected in Bavaria, Brandenburg, Saxony-Anhalt.

Very few people escape death when infected with the Borna virus. Even if they survived, they would face very serious consequences.

According to the Bavarian State Office of Health and Food Safety, BDV can cause encephalitis, which can lead to death. Symptoms of the disease are headache, fever, muscle weakness, fatigue. Then, they will experience neurological symptoms such as disturbances in behavior, voice, and gait. As the disease progresses, the sufferer will fall into a coma for a few days or weeks.

In particular, in addition to 3 survivors, all remaining cases died. There is no treatment for people or animals infected with this virus. After the first symptoms appear, the patient will die within weeks or months.

In most cases, even after surviving a viral infection, the person suffers lasting damage. The three surviving cases of this disease are still struggling with very serious consequences, unable to return to normal life.

The only natural host for the BoDV-1 virus at present is the shrew. The virus appears in the saliva, urine, and feces of this animal.

The risk of transmission of BoDV-1 to humans is very rare. With a human vaccine unavailable, health officials recommend reducing the risk of infection by avoiding contact with shrews and their droppings.