Second horse tests positive for West Nile virus

Test results for a second horse in the district thought to have succumbed to the West Nile virus came back positive late Friday.
“I wanted to know there was nothing I could have done. I wanted to know for sure,” said Faye Flatt, the owner of the Arabian horse which passed away Sept. 23.
Flatt noted she had suspected her horse had been infected with the mosquito-borne virus, but didn’t want to say much on the matter until she received the confirmation from Dr. Chris Cannon of the Nor-West Animal Clinic here late Friday.
Test results for rabies had come back negative earlier in the week.
Flatt said she’ll be certain to vaccinate her remaining three purebred Arabians against the West Nile virus, along with their other regular boosters next spring.
“It won’t do a lot of good now,” remarked Flatt, who lives about five km north of Devlin. “There’s two doses which are given four weeks apart, and then there’s a 10-day period for it to take effect.
“[But] the mosquito season is over,” she noted.
Dr. Cannon also had said last week that he highly recommends owners get their horses vaccinated next spring.
This latest incident came on the heels of a horse near Rainy River that was confirmed positive with the West Nile virus last month. The only other reported positive case of an infected horse in this area so far this year was in Littlefork, Mn. in August.
Flatt said horse owners should be aware of signs of the illness, which may include ataxia, difficulty walking, knuckling over, head tilt, muscle twitches or tremors, inability to stand, circling, weakness or paralysis of limbs, apparent blindness, lip droop, grinding teeth, and death.
West Nile virus is one of many causes of central nervous system disease in horses, including viral, bacterial, parasitic, developmental, or traumatic disease.
Clinical signs may be similar to other neurological diseases, including rabies.
Humans also can become infected with West Nile virus from mosquitoes, but are not as susceptible as horses to developing clinical disease.
Infected horses do not pose a threat to human health, but do indicate infected mosquitoes are present in the area.
A vaccine is available for West Nile virus on conditional release by the Canadian Food Inspection Agency through a licensed veterinarian.
This vaccine still is undergoing field trials and, although it meets all safety requirements, its effectiveness in preventing infection or clinical disease in horses has not been fully determined.
But the vaccine requires two doses given three-four weeks apart so full protection may not be achieved before the risk from mosquitoes naturally ends, usually by early October.
In related news, the Northwestern Health Unit said Tuesday they have stopped sending dead bird specimens away for testing until next summer. “Mosquito season is over,” noted Al Mathers, environmental health officer from the health unit office in Kenora.
“We said we would wait until there were three good frosts, and I think we’ve seen them,” he added.
In the past couple months, two dead crows—one in Kenora and the second most recently in Dryden—had tested positive for the West Nile virus. None were reported positive in the Rainy River District.