A viral horse disease that’s more prevalent further west in Canada has returned to Manitoba for the first time in recent memory, as horses from two municipalities have been found to caught the virus in the past four weeks.
Equine infectious anemia (EIA) was confirmed in horses from a property in the RM of St. Clements, north of Winnipeg, in early June, followed weeks later by a horse in the RM of Armstrong, in Manitoba’s Interlake region, according to a report from the Manitoba Horse Council.
The Equine Disease Communication Center, an arm of the American Association of Equine Practitioners, has reported the Armstrong horse was sampled as part of an investigation by the Canadian Food Inspection Agency into cases in St. Clements. The latter probe also includes a horse that had been moved to a breeding operation in Saskatchewan.
A federally reportable disease in Canada since 1971, EIA is a “potentially fatal” viral disease affecting horses and other equines such as donkeys and mules, with no human health risk, according to CFIA.
The disease has a history in Manitoba dating back to 1881 with the first recorded case in Canada, when it went by the name “swamp fever.”
However, the vast majority of Canada’s cases in the past 20 years have been in horses in Saskatchewan, Alberta and British Columbia, and no cases have been reported in Manitoba in recent years.
Apart from Manitoba’s new cases, EIA cases in 2017 have also been reported in the RMs of Torch River and Kinistino in northeastern Saskatchewan, at Mascouche in Quebec and in Beaver County southeast of Edmonton.
Most EIA-infected horses show no clinical signs of disease but will be carriers of the virus for life and can be a source of infection for susceptible animals. Foals infected with EIA before birth are often aborted, or die within two months of birth.
In infected horses, the virus’ incubation can range from one week to three months, with symptoms including anorexia, depression, general weakness, intermittent fever, jaundice, small hemorrhages under the tongue and eye, swelling of the extremities, and weight loss. In some cases, according to CFIA, a loss of co-ordination may be the only clinical sign.
Infected animals show temporary recovery from the severe stage of EIA and may even appear normal for two to three weeks before relapsing with similar, but less severe signs, CFIA said. Episodes of clinical illness are often associated with use of steroids or with periods of stress, such as hard work, hot weather, racing or pregnancy.
Horses or other equines confirmed with EIA are then either ordered destroyed by the CFIA or have to undergo lifelong quarantine.
EIA is transmitted mainly by transfer of contaminated blood from one animal to another, such as through horse flies, stable flies or deer flies, or when blood-contaminated objects such as needles or surgical tools are used on more than one animal. It can also be transmitted via semen from an infected stallion.
The disease so far has no cure, CFIA said, nor any vaccine to prevent an animal from becoming infected. — AGCanada.com Network