LARIMER COUNTY, Colo. — Two people have been confirmed for West Nile Virus (WNV) in Larimer County, according to the Larimer County Department of Health & Environment.

The cases were in Wellington and Fort Collins and neither person was hospitalized, the department said.

The Colorado Department of Public Health & Environment lists three confirmed cases in Colorado since June: two in Delta County and one in Boulder.

The third case, a woman over the age of 55, was confirmed with the virus, according to a notice Friday from Mesa County Public Health.

WNV is a viral infection that is spread to people by bites from infected Culex mosquitoes.

RELATED: West Nile Virus found in mosquitoes near Evans, Greeley

There have been several reports of WNV-infected mosquitoes in the state this year, in areas that include:

  • Evans
  • Greeley
  • Larimer County
  • Thornton

RELATED: West Nile-infected mosquitoes found in Thornton

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

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

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

About 75% of people who are infected do not show symptoms; about 25% will develop West Nile fever. Less than 1% develop the more severe neuroinvasive form, which can lead to hospitalization, critical illness, chronic disability or death. 

The Larimer County Health Department said WNV in humans can be prevented by following the "4 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.

WNV cases in humans tend to peak in August and September.

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