DALLAS (CBSDFW.COM) – Dallas County Health and Human Services reported the second, third and fourth human cases of West Nile virus infection in Dallas County for 2020 Thursday night.

The second patient is a 56-year-old resident of the 75238 zip code in Dallas and has been diagnosed with West Nile Fever.

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The third and fourth patients are 72 and 83-year-old residents of zip codes 75238 and 75230 in Dallas.

Both have been diagnosed with West Nile Neuroinvasive Disease. 

This season, mosquito samples have tested positive for WNV in the cities of Addison, Balch Springs, Carrollton, Cedar Hill, Coppell, Dallas, Desoto, Duncanville, Farmers Branch, Garland, Glenn Heights, Highland Park, Irving, Lancaster, Mesquite, Richardson, Rowlett, and University Park.

Ground spraying this week is scheduled in Dallas, Cockrell Hill, Duncanville, Lancaster, and Seagoville.

“The confirmation of these additional human cases of the West Nile virus here in Dallas County this year is another important reminder to the community of the need to take steps to avoid mosquito bites and to reduce mosquito populations,” said Dr. Philip Huang, Director of DCHHS. “The best way to avoid exposure to mosquito-borne diseases is to avoid mosquito bites by practicing the Four Ds.”

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• DEET: All Day, Every Day: Whenever you’re outside, use insect repellents that contain DEET or other EPA approved repellents and follow instructions.

• Dress: Wear long, loose, and light-colored clothing outside.

• Drain: Drain or treat all standing water in and around your home or workplace where mosquitoes could lay eggs.

• All Day long: Day, Dusk and Dawn – Limit your time outdoors mosquitos are active anytime day or night. WNV is a disease that is spread by the bite of an infected mosquito.

Mosquitoes can become infected when they feed on the blood from infected birds.

The infected mosquitoes can then transmit WNV to humans and animals. Severe WNV infections can cause neurologic complications such as encephalitis. Milder symptoms include fever, headache and muscle aches.

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There is no vaccine or specific treatment for WNV. For more information, click here.