Virus Shamonda: què és, com es transmet i què sabem sobre el primer cas en humans?

France has reported the first documented case of Shamonda virus infection in a human. The virus has been known to affect animals for decades and was detected in Europe for the first time in 2026. Despite this first human case, health authorities indicate that, based on the information currently available, no risk to the general population has been identified.

The Shamonda virus has attracted attention in recent days after France reported the first known case of infection in a human. Until now, the virus had mainly been detected in animals, particularly cattle, but also in sheep, goats and horses.

The case in France, which remains under investigation, involved a person who was severely immunocompromised. In light of this exceptional situation, the French authorities and the World Health Organization are investigating the circumstances surrounding the infection, the possible routes of transmission and the potential impact of the virus on human health.

What is the Shamonda virus?

The Shamonda virus belongs to the Orthobunyavirus genus, within the Peribunyaviridae family and the Simbu serogroup. It is related to other viruses that mainly affect animals, such as the Schmallenberg virus.

It was first identified in cattle in Nigeria in 1965. It was subsequently detected in animals in several African countries and in Japan. In June 2026, it was identified in Europe for the first time, specifically in cattle in Germany and Switzerland, and has since also been detected in other European countries.

Its presence has also been confirmed on cattle farms in Spain. In Catalonia, information published by the Government of Catalonia indicated that no suspected cases had been detected at the time of its latest update.

How is it transmitted?

The main known route of transmission of the Shamonda virus is through the bite of small insects of the Culicoides genus. These are tiny flying insects that can act as vectors and transmit the virus between animals.

In the case detected in France, the hypothesis under investigation is that the person may have acquired the infection through the bite of one of these insects in an area where the virus was circulating among animals and where Culicoides were present. However, further studies are needed to determine precisely how the human infection occurred and what the possible routes of transmission may be.

At present, there is no evidence that the Shamonda virus can be transmitted from person to person.

What symptoms does it cause?

In animals, particularly cattle, the infection can cause symptoms such as fever, diarrhoea and reduced milk production. Reproductive disorders have also been reported.

In humans, however, it is not yet possible to establish a characteristic set of symptoms associated with the Shamonda virus. Only one case has been documented so far and, therefore, the information currently available is very limited.

The person affected in France already had a serious illness and was severely immunocompromised. During the infection, they developed neurological complications that the French authorities consider likely to be related to the virus. However, based on a single case, it is not possible to determine whether these would be the typical symptoms of infection in humans or how the disease would progress in a healthy person.

Does the Shamonda virus pose a risk to the population?

Based on the information currently available, there is no cause for alarm.

The French authorities have indicated that no risk to the general population has currently been identified. Furthermore, the first human case occurred under very particular circumstances, as the person was severely immunocompromised.

The fact that a human infection has been identified for the first time is significant from a scientific and epidemiological perspective and warrants continued surveillance. However, a single case does not allow us to conclude that the virus is capable of routinely causing infections in humans or that it can be transmitted between people.

The World Health Organization is in contact with the French authorities to continue gathering information on the origin of the infection, possible routes of transmission and any potential risks to public health.

Therefore, at the Fundació Lluita contra les Infeccions, we would like to convey a message of calm while emphasising the importance of continued monitoring: this is a new situation that requires further study, but the information currently available does not indicate that the Shamonda virus poses a threat to the general population.