First Human Case of Shamonda Virus Confirmed in France
France has reported the death of the first individual infected with the Shamonda virus (SHAV), a pathogen primarily affecting livestock, including cattle, sheep, and goats, which was previously believed to be non-transmissible to humans. The French government has assured the public that, based on current knowledge of the virus, there is no significant risk to the general population. Nevertheless, health authorities are conducting a thorough investigation into the circumstances surrounding the case.
The fatality occurred earlier this month in Lyon, where the patient was suffering from severe immunosuppression. Preliminary indications suggest that the infection was acquired through a mosquito bite. An official statement noted, “The neurological complications observed in the immunocompromised patient prior to their death were very likely associated with the Shamonda virus infection.”
Understanding the Shamonda Virus
The Shamonda virus belongs to the Orthobunyavirus genus and is primarily transmitted through bites from Culicoides mosquitoes. First identified in Nigeria in the mid-1960s, sporadic infections have since been reported in livestock across West, East, and Southern Africa, as well as in Japan.
Cattle are considered the main hosts of this infectious agent, as they are not only susceptible to infection but also exhibit visible symptoms of the disease. Although sheep and goats can become infected, there have been no documented clinical manifestations in these animals to date.
The incubation period for SHAV ranges from two to three days, with symptoms in animals including fever, diarrhoea, and a decrease in milk production. In pregnant females, the virus can lead to miscarriages or serious fetal malformations. Currently, there is no vaccine available for the virus, and preventive measures rely on the application of insecticides and repellents.
European Context and Virus Risk Assessment
Despite health authorities classifying the case as “exceptional” due to the deceased’s underlying medical conditions, the incident has raised alarms across various European nations that were previously considered free from the virus.
In July, SHAV was detected in Central Europe for the first time as a variant known as Shamonda-Europe, initially affecting livestock in Switzerland. Subsequently, cases emerged in Germany, France, Austria, Belgium, the Netherlands, Liechtenstein, Italy, and Spain.
According to Spain’s Ministry of Agriculture, Fisheries and Food, two genetically distinct types of the virus, termed Shamonda type 1 and type 2, have been identified within Europe. At the beginning of September, infections from both types were reported in France, confirmed in livestock farms across 37 provinces.
Expert Opinions on the Virus’s Human Infection Potential
Previously, the Shamonda virus was thought to be non-transmissible to humans, making the documented case in France the first known instance of human infection. Ben Brennan, head of a research group and professor at the MRC Virology Research Centre and the University of Glasgow, described this as a significant scientific finding, noting it as the first recorded human case of Shamonda virus infection.
However, he cautioned against panic, stating that the unusual infection should be treated with care. He emphasised that the patient had a serious pre-existing condition that made them particularly vulnerable to infections, and it remains unclear whether the Shamonda virus contributed to their death.
David Roiz, a member of the SaBio Group at the Institute of Research in Game Resources, echoed the sentiment that it is too early to draw conclusions regarding the virus’s potential impact on humans. Nonetheless, he underscored the importance of scientific monitoring of the case.
“Many bunyaviruses circulate naturally among mammals in tropical regions and can occasionally infect humans. In a globalised world, where animals and goods are in constant motion and climate change is affecting ecosystems, it is not surprising that human transmission cases may arise. We should remain vigilant and proactive in addressing potential health risks,” he concluded.