Agencies spray for Asian tiger mosquitoes in the San Gabriel Valley

Trucks mounted with fog sprayers circulated through parts of the San Gabriel Valley on Wednesday morning spraying chemicals to combat an infestation of Asian tiger mosquitoes, known for their aggressive daytime feeding and ability to spread diseases.

Public health officials decided to spray in South El Monte, Arcadia and unincorporated Los Angeles County after finding adult tiger mosquitoes in traps in the area, according to Jason Farned, spokesman for the San Gabriel Valley Mosquito and Vector Control District, one of two agencies that carried out the sprays.

The spray contains two chemical formulas that kill adult mosquitoes and larvae.

The tiger mosquito, identified by its black and white stripes, can spread diseases such as dengue fever, as well as the lesser-known chikungunya. Both can cause joint pain and high fever, and spread easily, officials warn.

There is no evidence that any of the mosquitoes in the area are infected, according to Farned.

Officials advised residents to report sightings of the tiger mosquito and to clean up and remove standing or stagnant water, which provides a habitat for mosquitoes to breed in.

“The Asian tiger mosquito specifically can lay its eggs in a very small amount of water, in containers as small as bottle caps,” Farned said.

Matt Hansen can be reached at matt.hansen@latimes.com.