California’s first West Nile virus-positive mosquitoes of the year were found in the San Fernando Valley, vector control officials announced Monday.

The sample of infected mosquitoes was collected in a trap in Sun Valley, according to the Greater Los Angeles County Vector Control District.

Although mostly associated with summer months, mosquito season can start earlier, said Kelly Middleton, spokeswoman for the GLACVCD. Last year, California’s first West Nile virus positive mosquito sample was found in Sylmar in March.

“It’s great that the public is informed about Zika,” added Levy Sun, also a spokesman for the district. “But we can’t forget that, every year, West Nile virus is a more serious threat to Southern Californian families.”

Although the Zika virus has garnered more attention, 53 people died in California last year as a result of contracting West Nile virus, setting a state record. That’s the most since the California Department of Public Health began recording cases in 2003, and the most in any U.S. state.

West Nile virus is spread to humans by the bite of an infected mosquito. Infection occurs between mosquitoes and birds. In rare cases, a person can be become ill through a blood transfusion.

Most people infected with the virus do not become seriously ill, but some experience flu-like symptoms and about 1 percent of them can develop serious neurologic illness. People who are 50 and older or who have pre-existing medical conditions such as diabetes or high blood pressure have the greatest risk of developing complications.

Californians are urged to take precautions during warm temperatures by remembering the three D’s:

• DEET: Use it as insect repellent.

• Dawn and dusk: Mosquitoes bite in the early morning and evening.

• Drain: Eliminate all sources of standing water on your property, because that’s where mosquitoes breed.