Dallas County Health and Human Services says the first human case of West Nile virus has surfaced in Dallas County.
The victim lives in Richardson near U.S. 75 and Belt Line Road.
West Nile is commonly transmitted via mosquitoes. Most people who contract West Nile virus will suffer flu-like symptoms, though the severity of the virus can vary from person to person.
"Severe West Nile infections can cause neurological complications such as encephalitis. Milder symptoms include fever, headache and muscle aches," according to DCHSS.
On Wednesday, Richardson said they will extend spraying in the city based on positive mosquito pools and the human case of West Nile.
“We had planned to spray in the neighborhood around U.S. 75 and Belt Line Road later this week, but we’re also expanding our efforts to other parts of the community where the virus has been found in mosquito traps,” said Bill Alsup, director of the Richardson Health Department.
Dallas County has been spraying for mosquitoes in areas where testing of mosquito pools has shown the virus to be present. On Wednesday night, the county will spray in the Highland Park area. On Friday and Saturday spraying will take place in Singing Hills, between E. Ledbetter, University Hills, Camp Wisdom and Lancaster, and in part of Oak Cliff bound by Morrell, Marsalis, Illinois and Southerland avenues.
While the insecticide is considered safe, residents are advised to stay indoors during spraying.
In all, 17 pools have tested positive for the virus. See a map here. A rainy spring has proved to be a hardy breeding ground for mosquitoes. North Texans are encouraged to remove all standing water from their property so that mosquitoes have fewer places to lay their eggs. To take a virtual tour on how to safeguard your property, visit the Texas A&M University website here.
According to DCHHS director Zach Thompson, the number of mosquito pools found this season is "very alarming."
While this case is the first of the year for Dallas County, it is not the first human case of the year. Last month, human cases of West Nile were confirmed in Denton and Parker counties. The Denton County victim lived in an unincorporated, southern part of the county while the Parker County victim lived on the Parker/Tarrant county line.
NBC 5's Ken Kalthoff contributed to this report.