July 13, 2003 -- Monica Balderrama, KFOX News at Nine.

Almost everyone knows it by now: areas with stagnant water are perfect breeding grounds for mosquitoes. And the concern is mosquitoes carrying the West Nile virus. State officials say a horse in Sierra County was infected with West Nile and had to be killed. And with monsoon season coming up, animals are not the only ones at risk.

Colleen Gray knows the risks.

Colleen Gray-Horse Owner, "What we do is we keep area clean, keep your manure clean around the stall, we keep our fresh every day because mosquitoes will breed into the water."

The West Nile virus has attacked more than 15-thousand horses since it was discovered in 1991, and she doesn't want her horses to be the next victims.

Gray, "We keep the horses fairly clean the best that we can. We spay them with special spay, mosquito repellents, fly spray with mosquito repellant."

Monsoon season has resulted in a bumper crop of mosquitoes. Mosquitoes can carry West NiIe, a fast-spreading, potentially fatal virus. But West Nile virus isn't only a concern for horses, but people too.

Researchers have been investigating whether the virus is being spread through blood transfusions and organ transplants. That's why the Nation's Blood Supply Centers are now testing for West Nile.

Paula Villalobos-United Blood Services, "We have to be very cautious as to any virus that can be transmitted."

While there hasn't been a case in El Paso, last year someone undergoing an organ transplant was infected. And that's the tragedy health officials want to avoid.

Meanwhile horse owners want to avoid their own tragedies too. And horse owners like Colleen Gray are taking every precaution to keep their horses safe.

Gray, "You need to get with your vet, you need to put horses on regular vaccination schedule, the best time do it before mosquitoes start beginning of April."

While the vector control monitor, prevent and control mosquito populations to minimize any serious risk to humans, there are simple things you can do to reduce mosquito population around your house and to prevent bites.

Eliminate dirty gutters, fix leaky pipes, get rid of tin cans, jars and other containers in the yard. It's recommended you use personal repellants that contain the chemical deet, like Off!