No cases of West Nile found in district yet Mosquito trapping has resumed

The Northwestern Health Unit has been accepting dead crows and ravens suspected of West Nile-caused deaths for more than a month, but none have been confirmed positive yet.
“We’ve had a few [dead crows] submitted here, but had to reject them due to the severe state of decomposition they were in,” noted Al Mathers, environmental health officer with the health unit.
“Things don’t keep well in this weather.”
“There’s been none turned in at the Dryden office,” Mathers added. “I think the guys in Fort Frances have had a couple calls, but we haven’t had any test positive yet.
“It’s quite slow. From what I’ve heard, [the bird surveillance program] has been slow right across the province.”
The first crow in the Kenora-Rainy River districts that tested positive for West Nile virus last year didn’t turn up until late July. It had been collected in Kenora.
The first crows collected from Rainy River District that tested positive didn’t turn up until mid-August. Two of the trio were reported in Atikokan.
A total of eight dead crows in both the Kenora and Rainy Rivers districts tested positive for West Nile virus last summer. In 2003, there was a total of seven.
No birds collected in Rainy River District were found to be positive in 2002, but three did from Kenora District.
That same year, two horses—one in Rainy River and the other in Devlin—were confirmed positive for the West Nile virus. A third horse from Littlefork, Mn. died due to it in 2002.
Mathers noted no human cases of West Nile virus have been identified here so far.
This is the fourth year for the provincially-mandated bird surveillance program.
To report a suspiciously dead crow or raven, contact the health unit office here during normal office hours or call the after-hours number (1-807-468-7109) with the following information:
•your name, address, and phone number;
•location of the bird, including the town or municipality and street address (if it is a rural property, please provide as accurate a location description as possible);
•the date the bird was first noticed;
•description of the bird (note its size, and colour of the feathers, eyes, and beak);
•if you are aware the bird showed any signs of unusual behaviour before it died;
•physical condition of the bird (if there are any signs of trauma or insect activity); and
•the cause of death, if known.
The bird may be suitable for testing:
•if it has recently died;
•if there are no maggots on it; and
•even if it has signs of injury or trauma.
If the bird is suitable, the health unit will pick it up and send it away for testing at the University of Guelph.
If you are told by the health unit that the bird is not suitable for testing, bury it under at least two feet of earth or place it in two leak-proof bags and discard it in the garbage.
The health unit will continue to collect reports of dead bird sightings, as well as submit crows for testing when considered appropriate, until the mosquito season definitely is over.
Any updates on positive test results will be provided if or when they occur, Mathers said.
In related news, Mathers said the provincial campaign to monitor West Nile virus by collecting mosquito samples has started up again this year, with “mosquito traps” set up Kenora, Dryden, Fort Frances, and in the west end of Rainy River District.
Health unit staff in all these areas use traps to collect mosquito samples until early September. The purpose is to determine what species of mosquito are most common in the two districts.
This is the third year for this campaign, which has seen mixed results the past two years due to the unusually cool summers.
During the testing, the health unit is expected, if at all possible, to send in at least two mosquitos per week during the 10-week project.
To do the campaign, the health unit uses mosquito traps, which are comprised of a cylinder cooler, dry ice, a black light, fan, netting, and a small plastic bucket in which to collect the specimens.
The bugs are attracted by the carbon dioxide from the dry ice and black light. When they get close enough, they’re sucked into the netting by the fan.
Specimens collected then are sent in small cups for testing to Brock University in St. Catharines.
Mathers noted all of these came back negative for the West Nile virus in the past.
But one discovery the project yielded is that less than one percent of all the samples collected in the region were specimens of the main virus-carrying mosquito species, the Culex (or common house mosquito).
This means the chances of seeing the Culex breed (and thus the virus) here are slim, said Mathers.

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