OSOYOOS TIMES-August 26, 2009

By Laurena Weninger - Osoyoos Times

South Okanagan mosquitoes appear to be responsible for the first known cases of West Nile virus in British Columbia.
“Thursday, (Interior Health) was made aware of a possible human case of West Nile Virus,” said Dr. Paul Hasselback, medical health officer for Interior Health, in an email sent to local politicians on Saturday, Aug. 22. “That case has yet to be confirmed through national laboratory testing.”
The email goes on to say that very late on Friday, Aug. 21, a second case, related to the first, was also found to be positive on preliminary testing, and that both of the people— identified as Kelowna residents—  who tested positive had been travelling through Oliver and Osoyoos during the peak exposure time for the development of the disease.
“Also very late on Friday a mosquito pool, collected in the Oliver area, was found to be positive for the West Nile Virus.”
According to a government media release, the sample collected from the mosquito pool here in the South Okanagan tested positive for the virus at the Provincial Health Services Authority Laboratories at the BC Centre for Disease Control.
But what happens in a mosquito pool doesn’t stay in a mosquito pool.
“Does it really matter where they came from? No,” Hasselback said when asked directly the location of the affected mosquitoes. “It’s in the South Okanagan.”
The virus moves in birds, which travel a long way in a short time.
That means that even if the virus was found in one specific location, it isn’t going to stay put for long.
Hasselback said there have been a lot of cases in Washington state this year and there are monitoring stations all over the South Okanagan.
Light traps are used and one specific type of mosquito, the culex, is looked for.

“We know in the South Okanagan we have lots of these culex,” Hasselback said. “We’ve been expecting the arrival of West Nile Virus through the river valley.”
The people who have been affected are both adults and both in the same family unit, Hasselback said.
One of them is older than 50, but the age of the other is not being disclosed.
The illness is self-limiting, meaning it gets better on its own in a matter of a few days. Eighty per cent of those affected have no symptoms at all and may not even know they have had the infection.
The other 20 per cent could develop an illness with fever, headaches and rash symptoms.
“Rarely can the disease be fatal,” Hasselback said.
But one in 150 cases can be significantly severe, causing inflammation of the brain and the brain lining – and the risk goes up for those over 50 years of age and those with underlying health conditions.
“Symptoms are severe enough that they will bring people to the hospital,” Hasselback said.
The symptoms could include headache, confusion, a lack of coordination or trouble speaking.
The best protection is to use a mosquito repellant containing DEET and to avoid being outdoors at dusk and dawn, when the insects are active.
Residents should also take care to clean up areas where mosquitoes like to breed, such as pools of standing water, at least once a week to interrupt the breeding cycle.
reporter@osoyoostimes.com