When horses hit their heads against the walls of their stalls, the virus begins to take them away.
Since the end of February, an epidemic of rhinopneumonia has been wreaking havoc in the equestrian world.
First alert at the end of February in Valencia, Spain, where a horse racing event brought together nearly 800 mounts, including a hundred showing symptoms of the disease.
Since then, several other outbreaks have been confirmed in France, pushing the industry to take preventive health measures to prevent the spread of the virus.
"I went down with 17 horses, all 17 were affected, and I lost a mare," said Franck Curti, owner who remained in Valence at the bedside of his horses.
"Veterinarians have never seen that, (...) this nervous form of the disease has become very aggressive".
Rhinopneumonia is a disease well known to the equestrian world.
It results in fever - the temperature of horses can rise to 40 ° C - breathing problems, difficulty urinating or defecating, and especially a general weakness.
"In its severe form, it is fatal once in two", explains Mathieu Houssin, equine veterinarian.
Horse riding: concern grows with the virus that can kill horses
Faced with this strain which has already caused 11 deaths, the international equestrian sports federation has qualified it as "the most serious epidemic in Europe for decades".
To fight against its spread, the French federation has banned all gatherings, competitions and equestrian courses at least until the end of March.