Dallas County has declared a state of emergency as the nation battles a West Nile Virus outbreak that has hit the state of Texas hard, killing 14 people.

Dallas Mayor Mike Rawlings requested on Wednesday that the county and the state conduct aerial pesticide spraying to control mosquitoes, the primary agent for spreading the West Nile Virus. (Find spraying time and date here.)

Rawlings' emergency declaration frees up money and other resources that will be used to stem the outbreak. Ten of the reported 14 deaths were from Dallas County.

"I think this is the right thing to do," Rawlings told The Dallas Morning News. "I cannot have any more deaths on my conscience because we didn't take action."

Data provided by the Centers for Disease Control and Prevention showed 693 cases of West Nile Virus reported nationally as of August. Texas accounts for nearly half of the reported cases. Nationally, there have been 26 deaths.

The West Nile Virus is spread when an infected mosquito bites a person. Mosquitoes become infected with the virus when they feed on infected birds, according to the CDC. An infected human can spread the virus through blood transfusion or breastfeeding. The West Nile Virus cannot spread through touching.

The virus can cause serious illness. People usually develop symptoms between three and 14 days after being bitten. Sever symptoms can include high fever, headache, neck stiffness, disorientation, coma and tremors. Milder symptoms of those infected with the West Nile Virus include fever, head and body aches, nausea and vomiting.