Maryland is spraying areas of Anne Arundel County to control mosquitoes after the detection of West Nile virus.
The Department of Agriculture says heavy rain earlier in the summer hatched a high concentration of mosquitoes that can spread the disease in the area.
Officials say the spraying on Wednesday night targeted a one mile radius around the home of a person who was infected with the virus. Sprayers will go out again in the county Thursday night.
Most of those infected will not have any symptoms, which can include fever, headache, body aches, rashes and swollen lymph glands. And less than 1 percent of those exposed will develop more severe infections. In rare instances, the virus can be fatal.