The Cascade County Weed & Mosquito Division has detected its third West Nile Virus positive mosquito pool this summer.

That makes three positive mosquito samples within a three week period.

A positive sample of Culex tarsalis was collected about four miles west of Vaughn along the Sun River on Aug. 29 and was confirmed to be West Nile Virus positive by the lab at the Montana Department of Public Health and Human Services in Helena on Aug. 30.

The first positive pool this year in the county was detected in the Gerber area and confirmed positive by DPHHS on Aug. 21. Another positive sample was collected Aug. 28 at the Benton Lake National Wildlife Refuge Complex, about eight miles North of Great Falls. DPHHS confirmed that sample to also be positive for West Nile Virus.

So far, there are still no known infections in humans, but because samples continue to test positive, residents are “greatly encouraged” to take steps to protect themselves.

Severity and symptoms of West Nile Virus can vary widely and about 80 percent of those infected experience no symptoms, but up to 20 percent of people can develop a mild illness, called West Nile fever.

The fever generally goes away without treatment, according to the City-County Health Department. But dangerous brain infections such as encephalitis or meningitis can develop in one out of 150 people. According to CCHD, those symptoms of these diseases might include headache, rash, high fever, stiff neck, mental confusion, muscle weakness, tremors, convulsions, coma, and paralysis.

Anyone who develops any of these symptoms should see their healthcare provider immediately.

The best way to prevent infection is bite prevention.

CCHD recommends the five D’s:

• DEET- Apply repellent containing an EPA-registered active ingredient, such as DEET, and follow the directions on the package;
• DUSK and DAWN- This is when mosquitoes are most active. Try to avoid outdoor activities during these times;
• DRAIN STANDING WATER- Standing water is the perfect breeding ground for mosquitoes. Drain such areas around your home including gutters, pools, tires, buckets, water bowls, etc;
• DRESS APPROPRIATELY- Wear long-sleeved shirts, long pants, and socks.

For more information, visit the CCHD website or the DPHHS website.