And it’s time to think about West Nile virus — and what we can do to prevent being bitten by the mosquitoes that spread it to hu-mans.

A 51-year-old person from Douglas County has been diagnosed with West Nile virus, said Sharon Watson, communications director for the Kansas Department of Health and Environment.

In mid-May, the Douglas County resident, whom Watson declined to identify as a man or a woman, sought medical advice for what seemed to be symptoms of West Nile virus.

Typically, Watson said, this means the patient may suffer from headache, fever or muscle aches. She said that in some cases the symptoms will be so mild that people don’t know they’ve been infected with West Nile virus.

“The preliminary test that the physician had done indicated West Nile virus and the symptoms pointed to West Nile virus,” Watson said of the Douglas County resident. “They (medical professionals) weren’t able to explain the symptoms with any other illness.”

Also, Watson said, the person’s blood tested positive for West Nile virus.

Watson said KDHE had reported the case to the Centers for Disease Control as probable West Nile virus.

She explained that once a person has had West Nile virus, it will always show up in their blood tests.

“Once they get it, they’re immune to it for life,” Watson said. “It will show up in blood tests for the rest of their lives. If you go to give blood and you’ve had West Nile virus, it will show up in that as well.”

Gary Tegtmeier works at Community Blood Center in Kansas City, Mo., where he’s director of the viral testing lab.

Since summer 2003, all blood donations at Community Blood Center have been screened for West Nile Virus. The blood center collects blood in western and central Missouri and eastern Kansas, including the Tonganoxie area.

In 2003, Tegtmeier said, about six donors tested positive for West Nile Virus.

“Last year we only had two donors who were positive,” Tegtmeier said.

The disease is still fairly rare, and often, unless blood is tested, it goes undetected, Tegtmeier added.

“Eighty percent of the people who are infected (with West Nile Virus) never have any symptoms, or at least they’re so mild that they don’t come to the person’s attention,” Tegtmeier said.

Tegtmeier said, according to new FDA guidelines, blood donors who have had West Nile Virus must wait 120 days after their symptoms have ended before they can donate blood.

Prevention

Birds carry West Nile virus, Watson said.

“Mosquitoes bite the infected birds and transmit the virus to other birds, horses or people,” Watson said, noting more than 100 species of birds have been known to be carriers of West Nile virus.

In humans, symptoms can appear from three to 14 days after being bitten by an infected mosquito.

Watson said the best advice for preventing West Nile virus is to use mosquito repellents that contain DEET.

“It’s also a good idea to wear protective clothing, especially when you’re out at dawn and dusk when mosquitoes are active,” she said.

And it’s important to remove standing water from around your home, Watson said.

“Mosquitoes like to use stagnant water as a breeding ground,” she added.

Livestock watering tanks and drainage ditches — anywhere there’s standing water — also are breeding grounds for mosquitoes.

In these areas, Watson advises using larvicides, to kill the mosquito larvae. The products, available at hardware stores, won’t harm fish or livestock, Watson said. And, she said, goldfish added to large areas of standing water will eat mosquito larvae.

Though the Douglas County resident’s recent bout with West Nile virus was mild, not everyone is so lucky.

“The symptoms were the less severe form,” Watson said. “Not the encephalitis or meningitis form where it causes severe conditions such as difficulty walking or difficulty thinking or functioning.”

And she said, the disease can be harder on people who are older than 50, as well as those who have weakened immune systems.