WELD COUNTY, Colorado — Mosquitoes in the Greeley and Evans area have tested positive for West Nile Virus (WNV), increasing the risk for human infection, according to Weld County health officials.

Although no human cases have been reported so far in 2019, Weld County officials said they expect that to change with the increase in mosquitoes infected.

Mark Wallace, executive director of the Weld County Health Department, said the hot and humid August weather and afternoon thunderstorms create "the perfect conditions" for the Culex mosquito — the mosquito species that carries WNV.

"It’s extremely important to avoid getting bit by mosquitoes," Wallace said.

WNV symptoms can appear three to 14 days after an infection. Initial symptoms include:

  • Fever
  • Headache
  • Nausea
  • Vomiting
  • Muscle aches
  • Weakness
  • Rash

Most people infected don't exhibit any symptoms, but anyone experiencing those symptoms should seek medical help immediately, the Health Department said.

There are no medications for WNV, and there are no vaccinations to prevent infection. Less than 1% of people develop a serious (sometimes fatal) illness.

To prevent mosquito bites, health officials recommend following the "four 'Ds'":

  1. Drain standing water around your house weekly. Remember to drain water from tires, cans, flowerpots, clogged rain gutters, rain barrels, toys and puddles.
  2. Dusk and dawn are when mosquitoes are most active. Limit outdoor activities and take precautions to prevent mosquito bites during these times.
  3. Deet is an effective ingredient to look for in insect repellents. Other repellents containing picaridin, IR3535, oil of lemon eucalyptus or para-menthane-diol are also effective against mosquitoes. Always follow label instructions carefully.
  4. Dress in long sleeves and pants where mosquitoes are active.

Mosquitoes in Larimer County tested positive for West Nile on July 30.

RELATED: First West Nile positive mosquitoes of the year found in Larimer County

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