Shamonda Virus Infection in Humans – France

Shamonda Virus Infection in Humans – France

Update #1 Date- 02/11/2026

Occurrence Update

France has reported the first laboratory-confirmed human infection with Shamonda virus (SHAV), resulting in the death of an immunocompromised older adult male.

On 20 October 2026, French health authorities notified the first documented human case of Shamonda virus infection globally.

The patient, who lived in eastern France and had no history of international travel during the preceding year, developed severe neurological symptoms on 23 September 2026, including visual disturbances, confusion, loss of consciousness and seizures.

He was diagnosed with severe encephalitis (inflammation of the brain) and died on 8 October 2026.

Laboratory investigations confirmed the presence of the virus through metagenomic sequencing and reverse transcription polymerase chain reaction (RT-PCR), with high viral loads detected in post-mortem tissue samples.

About Shamonda Virus

Shamonda virus belongs to the family Peribunyaviridae, genus Orthobunyavirus, and Simbu serogroup.

It was previously recognized primarily as an animal-associated virus and has been identified in cattle and other animals in parts of Africa, Japan and Europe.

Animal Infections and Geographic Spread

During the summer of 2026, the virus was detected in cattle, horses and alpacas in several European countries, including Belgium, France, Germany, the Netherlands and Switzerland.

By 21 October 2026, additional animal detections had been reported in Austria, Ireland, Jersey, Liechtenstein, Portugal, Slovenia and Spain.

In France, animal infections had been reported across 54 departments, predominantly among cattle.

Possible Transmission

The exact source and route of human infection remain unknown.

However, vector-borne transmission is considered a plausible route, with biting midges of the genus Culicoides believed to play a major role in transmitting the virus among animals.

Mosquito exposure was also reported in the patient’s history, although its role in transmission has not been established.

Food-borne transmission is considered unlikely but remains under investigation, particularly regarding the possible presence of the virus in milk from infected cattle.

Investigations into blood transfusions also found no evidence of infection among the tested blood donors, making transfusion-associated transmission unlikely.

Human Health Situation

As of 2 November 2026, this remains the first laboratory-confirmed human infection with Shamonda virus reported globally, and no additional human cases have been detected.

There is currently insufficient evidence to determine the frequency, clinical severity or extent of human infection, particularly among individuals with normal immune systems.

Treatment and Vaccine

No specific antiviral treatment or vaccine is currently available for Shamonda virus.

Public Health Response

Veterinary and public health investigations are continuing to identify potential transmission routes, vectors and associated risks.

Strengthened surveillance, laboratory investigations, information sharing and coordination between human, animal and environmental health authorities through a One Health approach remain essential to understand the epidemiology and potential public health implications of this emerging infection.

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