Then the patient went back to eating his hay. The gray Irish Sport Horse, named McCoy, tested negative for an illness currently devastating European equestrian sports. An outbreak of a neurological form of the common equine herpes virus has killed nearly 20 horses and sickened over 100 more. It has forced the shutdown of competitions across 10 European countries.

With eerie echoes of the human coronavirus and the current pandemic, the virulent equine virus, which can kill a horse in less than 24 hours, has raced through the sport horse industry at a time when experts say it can least afford it: The shutdowns to stop the spread of the virus, known as EHV, come after nearly a year of shutdowns in the face of Covid-19. The coronavirus closed barns and cancelled international championships, including last year’s World Cup Finals for dressage and show jumping, an important Olympic proving ground.

The event was to take place this week in Gothenburg, Sweden. Instead, on March 12, it was cancelled again.

“On the back of Covid, which is of course still having a devastating impact worldwide, this EHV-1 outbreak has been particularly tough,” Dr Goran Akerstrom, the veterinary director of the Fédération Equestre Internationale, or FEI, the international governing body of equestrian sports, said in an email. “Particularly for those that have lost horses.”

He added, “To lose the FEI World Cup Finals two years in a row — and to two different viruses — has been incredibly hard.”

The outbreak began at an international competition in Valencia, Spain, in late February, killing several top German show horses on the grounds. Organizers locked down some of the 752 animals in attendance, but some riders had left with their animals for their home countries — unwittingly taking the virus with them. The virus has since been identified in 10 nations — Spain, Italy, Switzerland, Germany, France, Belgium, Denmark, Sweden, Slovakia and Qatar — possibly linked to the Valencia event. The United States has been spared, so far.

“I still can’t believe that we had no opportunity to help you,” Tim-Uwe Hoffmann, a German rider, wrote on Instagram in tribute to his mare, Casta Lee FRH, who died after testing positive at the Valencia show.

The FEI has ordered international competitions on mainland Europe shut until at least mid-April. Nearly 4,000 horses who were in contact with potentially contagious animals after the show in Valencia have been ordered isolated for 21 days by the federation, which is conducting a sweeping test-and-trace initiative across European farms. After the isolation ends, they must return a negative PCR test to return to competition.

“It was basically a textbook superspreader event,” Dr Allen, McCoy’s owner, said of the Valencia competition. Dr Allen is a veterinarian based in Middleburg, Va., who also serves as the FEI’s head veterinarian for the United States.

The equine herpes virus is not a new enemy; it is endemic in the horse population and typically manifests as a runny nose and fever. But the version that has raced through barns after the Spain outbreak is far more deadly. It invades the central nervous system and causes myeloencephalopathy, or inflammation of the brain and spinal cord. The death itself, veterinarians say, is swift but brutal.

— NYT