“Vole fever” which can trigger the spread of the Ebola-type hemorrhagic virus in Europe

A POTENTIALLY deadly virus capable of jumping from rodents to humans and triggering Ebola-like hemorrhages is spreading across northern Europe.

Researchers have discovered that Swedish rodents carry a pathogen that can transmit to humans and develop into hemorrhagic fever.

Cases of illness are being spotted hundreds of miles from where health officials typically see this virus, raising concern among scientists.

It all started when doctors in Scania County, southern Sweden, diagnosed a case of epidemic nephropathy, caused by the Puumala virus carried by riverside voles, in 2018.

Epidemic nephropathy is also called “vole fever” and is a rare disease that can cause hemorrhagic fever in humans.

Hemorrhagic fevers are a group of illnesses caused by different viruses that can be serious and life-threatening. These include yellow fever, Ebola and Crimean-Congo hemorrhagic fever.

Doctors were stunned to detect a case of vole fever this far south of the country, more than 500 km south of where the disease had previously been detected.

Another case was spotted in 2020, also in Scania County in Sweden.

In both cases, the patients had not traveled and were infected in their region of origin.

Their symptoms were typical of hemorrhagic fever with renal syndrome (HFRS), including fever, general malaise, nosebleeds and poor kidney function.

Both patients recovered from their infections, but it prompted scientists at Uppsala University to examine why vole fever infections were appearing so far from where they usually occur.

They carried out genetic testing on bank voles in Scania County, capturing them near patients’ homes and analyzing them for the presence of hantavirus.

Hantaviruses are a family of viruses found primarily in rodents like mice, rats, and voles.

Some hantaviruses are capable of infecting humans and causing two types of illness: hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS).

According to scientists from Uppsala University, both types of diseases must be reported under the Communicable Diseases Act, because they can cause serious problems or even death.

In northern and central Europe, a variant of the virus – called Puumala hantavirus – causes a relatively mild form of HFRS.

However, studies have shown that this hantavirus can also cause very serious HRFS, which in the worst case can be fatal.

In Sweden, around 100 to 450 cases of vole fever require hospital care each year in the northern part of the country alone.

The scientists’ analysis revealed that nine of 74 voles captured in the southern region of Skåne carried hantavirus genes.

They also discovered that the virus infecting rodents in this region was not the same strain found in northern Sweden.

Instead, it was a distinct variant closely related to the Puumala viruses of Finland or Russian Karelia, located hundreds of miles away.

Somehow, this strain of the virus that causes hemorrhagic fever had appeared in the bank vole population of southern Sweden, most likely within the last decade.

Although only two human cases have been identified so far in southern Sweden, scientists fear this emerging virus strain poses a threat to public health.

“New strains of Puumala virus in a new geographic area could have a substantial effect on human health,” researchers wrote in a study published in the journal Emerging Infectious Diseases.

Elin Economou Lundeberg, study author and infectious disease doctor at Kristianstad Central Hospital, said: “We were surprised to find that such a high proportion of the relatively few voles we captured were in actually carry a hantavirus that makes people sick.

“And this was in an area more than 500 km south of the previously known virus spread zone.”

Researchers now intend to find out where the virus comes from and map its distribution in southern Sweden.

Professor Åke Lundkvist of Uppsala University, co-author of the study, wondered: “If the virus has existed in the region for a long time and simply hasn’t been discovered, why aren’t more people Didn’t they get sick?

“Or has it recently established itself in Scania County and just started to spread? And how did it get there?

“Unfortunately, the COVID-19 pandemic intervened, which significantly delayed the completion of this study.

“These results are very interesting and show how important it is to investigate the causes as quickly as possible when we see an infectious disease in a new geographic area.”

OTHER OBSERVATIONS OF HEMORRHAGIC FEVER

This is not the first time that the alarm has been sounded regarding cases of hemorrhagic fever in Europe.

Crimean-Congo hemorrhagic fever is a viral disease commonly seen in regions such as Africa, the Middle East, and West and South Central Asia.

But the virus has caused significant outbreaks in the Balkans and Turkey, as well as in Russia, according to the European Center for Disease Prevention and Control (ECDC).

It has also been spotted in popular vacation spots like Spain.

In April 2024, a person died in Salamanca province after contracting Crimean-Congo hemorrhagic fever while hiking.

A forestry worker in León province also died from fever in 2022, while another person was infected by a tick bite but recovered.

Crimean-Congo hemorrhagic fever is usually spread through tick bites, which are “widely distributed in southern and eastern Europe,” according to the ECDC.