Outbreaks of equine infectious anemia (EIA) have recently occurred in three European countries and are currently unresolved, according to local and international health authorities.

Four French horses, two German horses, and a Greek horse have been declared positive for the EIA virus via blood tests in the apparently unrelated outbreaks since late 2011. The French and German horses were euthanized in January, and the Greek horse died in October, according to the World Organization for Animal Health.

While the German horses were on two separate farms in different areas of the country, the four French horses were all on the same farm, said Frédéric Poudevigne, DVM, head of health services and animal protection at the French Departmental Direction of Population Protection. The two mares and two geldings were housed on a private farm and boarding stable along with four other horses, which were tested negative. Only one of the horses showed clinical signs, including fever and swelling, Poudevigne said.

Two of the French horses participated in a weekend-long rally event last September in the Mediterranean region of Vaucluse, Poudevigne said. The horses competed and were housed overnight with approximately 160 other horses, which could have been contaminated. All the horses from the event are currently being tested; results will be available next week, he said. Meanwhile all farms housing horses from that event are on full quarantine until further notice