Swamp fever rearing its head in 2018

Horses infected with equine infectious anemia may show some, all or none of the following:

One case of equine infectious anemia, also known as swamp fever, has been found in Alberta within the past month.

The Canadian Food Inspection Agency confirmed March 1 that a case had been found in a horse in Strathcona County near Edmonton.

It is just the most recent incident of a complex disease that confounds horse owners in part because it is sometimes invisibly carried and spread by horses with no symptoms.

EIA is a reportable disease and there is no cure or vaccine. The CFIA said the Strathcona case was confirmed Feb. 21 after the affected horse showed signs of the illness.

The horse was euthanized and a CFIA investigation is underway. A quarantine has been placed on other horses at the same premises.

Equestrian Canada said in a news release that the quarantine would remain until testing of the other animals was complete. A trace-out by the CFIA might involve other horses on other premises.

Last year Alberta confirmed EIA at Beaver, Red Deer, Two Hills, Sturgeon, Lacombe and Newell counties. Nine horses were infected.

Saskatchewan had cases in two rural municipalities, with eight infected horses in Kinistino and one in Torch River.

Manitoba had seven incidents, two of them in the RM of Armstrong that affected 10 animals. The others, infecting a total of seven animals, were in the RMs of St. Clements, St. Andrews, Hanover, Springfield and Rosedale.

Over the past six years, Alberta and Saskatchewan have had 86 percent of the positive EIA cases. From 2012-17, Saskatchewan had 67 percent, followed by Alberta at 19 percent, according to CFIA data.

The department has thus proposed primary and secondary control zones for EIA, though the exact boundaries have yet to be determined.

EIA is transmitted by blood, through biting insects or needles, syringes and blood-contaminated objects. The difficulties associated with spread by flies in particular means that cases continue to appear across Canada.

“It is a terrible disease,” said Bill desBarres, chair of the Horse Welfare Alliance of Canada.

The virus can affect donkeys and mules as well as horses, and causes recurrent episodes of fever, lethargy and anemia in affected animals. However, some animals can carry the disease without showing symptoms and act as carriers.

“We have a lot more than we are aware of,” desBarres said about the number of cases. “We have no idea how many positive horses are driving around.”

The most common test for EIA is known as the Coggins test, which is required on horses that leave or enter the country.

Other than on those occasions, desBarres said many horse owners are reluctant to have their horses tested, fearing a positive result and the subsequent loss of their animals.

“We’re trying to get more information out to horse owners so they want to test,” he said.

Ideally, owners would have their horses tested whenever they are taken to horse shows or other places where they mingle with other horses.

However, there is a cost to the test and results can take two weeks.

The Horse Welfare Alliance is seeking ways to improve the practicality of testing and reduce the costs.

As for prevention, biosecurity, fly control and using clean needles and other instruments are the only known options.

Symptoms of EIA

Horses infected with equine infectious anemia may show some, all or none of the following:

  • anorexia
  • depression
  • general weakness
  • intermittent fever
  • jaundice
  • bleeding under tongue and eye
  • swelling of extremities
  • weight loss
  • loss of co-ordination

Source: CFIA

About the author



Stories from our other publications