“We have gotten positive results back in one zip code so we waited a little bit and continued the larva sighting,” Shelby County Environmental Health Services Administrator Kasia Smith-Alexander said. “Now that we’ve gotten additional positive testing within the mosquitoes we decided to go ahead and begin spraying.” Three nights this week Vector Control will spray EPA-approved insecticides to control the mosquito population. They’ll start in the areas where infected mosquitoes were found- zip codes 38118 near the airport, 38115 in Hickory Hill, 38104 in midtown and 38133 in Bartlett.