The first human cases of West Nile Virus have been reported in Oklahoma, the state health department said Friday.

Three people are confirmed positive of having West Nile Virus. 

The cases were from Canadian, Grant and Tulsa counties.

West Nile Virus is spread through the bite of a Culex mosquito, which feeds on infected birds and transmits the virus when biting humans, horses or other mammals. 

This type of mosquito increases in numbers during mid- to late summer when the temperatures climb and the weather pattern is dry.

Symptoms for West Nile Virus include sudden onset of fever, headache, dizziness and muscle weakness. 

Those older than the age of 50, diabetics, or those suffering from uncontrolled hypertension are at greater risk of developing severe neurologic disease from West Nile Virus.

Here are some ways to avoid mosquito bites: 

  • Use an insect repellent containing DEET, picaridin, or IR3535 on exposed skin and clothing when going outdoors, particularly between dusk and dawn when mosquitoes are more likely to bite. Insect repellent with permethrin should be used on clothing only.
  • Repair or install window and door screens to keep mosquitoes out of the home.
  • Prevent items such as buckets, cans, pool covers, flower pots, children’s toys and tires from holding water so mosquitoes don’t have a place to breed.
  • Empty a pet’s outdoor water bowl and refill daily.
  • Scrub and refill bird baths every three days.
  • Clean leaves and debris from rain gutters regularly to ensure they are not clogged.