HOUSTON -

A mosquito has tested positive for the Chikungunya virus and nine people have tested positive for the West Nile virus, according to the Harris County Public Health and Environmental Services.

One person has tested positive with the Chikungunya virus, but that that person was infected elsewhere and brought the virus to Harris County.

The county's Mosquito Control Division says nine people have tested positive for the West Nile virus, but none of the cases have been fatal. More than 730 samples have tested positive for West Nile. The samples confirm the existence of West Nile in mosquitoes in more than two-thirds of the county. The county says 107 of the 154 zip codes in Harris County tested positive.

The Mosquito Control Division will use an airplane to spray for mosquitoes Thursday evening in the northeast and northwest parts of the county. It routinely sprays on the ground and will focus on areas of the Heights Wednesday night.

The county has about 20 trucks that start spraying at dusk and spray all night.

As long as the weather cooperates, the county will spray 138,000 acres in the following zip codes: 77375, 77389, 77388, 77379, 7707077069, 77068, 77090, 77346, 77396, 77044, 77050, 77078.

Some zip codes will only be partially sprayed.

"Because of the increased number of disease infected mosquitoes detected by our surveillance efforts, this aerial spray operation will help us better protect the health of our community," Director of Harris County Public Health and Environmental Services Mosquito Control Division Dr. Mustapha Debboun said.

Dibrom is an insecticide that will be sprayed. The county says it is EPA approved and considered safe for the environment.

Local 2 is working to gather more information about this story and will have a report Wednesday on Local 2 News at 10 p.m.

Are mosquitoes bad in your neighborhood? Reporter Jace Larson is talking about the problem on his Facebook page.