The mosquito samples were taken from Sherman Oaks and Porter Ranch.
RELATED: West Nile virus confirmed in LA County
The first mosquitoes to test positive for the year were found in Panorama City last week.
Officials are reminding people to get rid of any standing water on their properties because those spots can become mosquito-breeding sites.
RELATED: 2 cases of West Nile virus confirmed in Riverside County
It's also important to wear mosquito repellent when outside to prevent being bitten and infected by the virus.
The virus is transmitted to people and animals through the bite of an infected mosquito. There is no cure for it.
One in five people infected with the virus will exhibit symptoms such as fever, headache, body aches, nausea or a skin rash. The symptoms can last for several days to months.