First Human Case of Shamonda Virus Found in France
France has identified the first known human case of Shamonda virus. The infected person died after developing the infection. Health experts currently view the case as isolated, and the risk to the wider public is considered low.
International health teams are working with French health authorities to learn more about the case. Investigators are examining how the person became infected and whether the virus played a role in the death.
A Virus Usually Found in Farm Animals
Shamonda virus mainly affects livestock. It was first identified in cattle in Nigeria in 1965. Since then, infections have been found most often in cattle, although the virus can also affect sheep, goats, horses and alpacas.
Animals infected with the virus may develop several health problems, including:
- Fever
- Diarrhea
- Lower milk production
- Abnormal development in unborn calves
In some cases, infected animals may show few or no clear signs of illness. This can make it harder to recognize the virus without laboratory testing.
The Virus Has Reached Europe
Most known cases of Shamonda virus have been found in Africa and Japan. It was later detected in cattle in southern Germany and Switzerland, marking its first known appearance in Europe.
The virus has since been found in animals in several other Western European countries, including Austria, Belgium and France. Its spread among livestock has increased attention from animal and public health experts.
Even though the virus is now present in parts of Europe, its behavior there may not be the same as in regions where it has circulated for many years. Weather, insect populations and animal movement can all affect how the virus spreads.
Small Biting Insects Carry the Virus
Shamonda virus is passed to animals through the bite of a Culicoides midge. These insects are tiny and resemble small flies. More research is needed to determine which exact midge species are able to carry and transmit the virus.
The virus is not known to spread directly from one animal to another. One important exception can occur during pregnancy, when an infected animal may pass the virus to its unborn fetus.
Shamonda virus belongs to a group called Orthobunyaviruses. It is part of the Simbu subgroup, which also includes Schmallenberg virus. Diseases in this group often appear in cycles linked to the seasonal activity of biting midges.
Those patterns may change in Europe. The insects may behave differently there because of local temperatures, rainfall and other environmental conditions.
Why the Human Risk Is Thought to Be Low
French investigators believe the person may have been bitten by a midge carrying Shamonda virus. However, the exact route of infection has not been confirmed.
The patient was also being treated for a serious medical condition. That illness may have made the person more vulnerable to infections than most people. Further testing is needed to determine whether Shamonda virus caused or contributed to the death.
Viruses in the same broad family do not all affect people in the same way. Some can infect humans more easily than others. Because of this, laboratories must use careful safety procedures when handling samples that may contain the virus.
The single known human case does not show that Shamonda virus is spreading widely among people. There is currently no evidence of regular person-to-person transmission, and the public health danger remains low.
Limited Testing Makes Cases Hard to Track
Countries are encouraged, but not required, to report Shamonda virus cases in animals. This means the total number of infections may be higher than the known count.
Confirming the virus also requires laboratory testing. Fever, diarrhea and reduced milk production can occur with many livestock diseases, so symptoms alone cannot identify Shamonda virus.
There is currently no specific treatment or vaccine for Shamonda virus. Monitoring livestock, testing suspicious cases and tracking the insects that spread the virus remain important tools for understanding its risks.