A highly-targeted approach for the control of yellow fever mosquito infestations in Southern California.

In the Targeted Yellow Fever Mosquito Control Program, Vector Control will release male yellow fever mosquitoes (Aedes aegypti) in a localized area of East Los Angeles.

Male mosquitoes do not bite.

These male mosquitoes are dusted with a small amount of an insect growth regulator (IGR) called pyriproxyfen, which prevents mosquito larvae from maturing to adults. The released males will mate with wild female yellow fever mosquitoes in the infestation zone and transfer some of the dust to the female in the process. When the treated female lays her eggs in water-holding containers, she deposits some of the dust into the water. Larvae will hatch from the eggs, but the offspring will not survive. Dusted male mosquitoes will also transfer the IGR to water sources they visit.

This pilot program will determine how effective this novel strategy will be in the District’s overall Invasive Aedes Mosquito Control Program.

This technique targets the yellow fever mosquitoes (Aedes aegypti).

Yellow fever mosquitoes have taken broad hold in an increasing number of neighborhoods in Los Angeles County since they were first detected in 2014. Despite intensive traditional mosquito control efforts, they have continued to spread.

As the infestation expands and mosquito numbers increase, the risk for local disease outbreaks of Zika, chikungunya, dengue, and yellow fever, is also elevated.

communities experiencing yellow fever mosquito infestations in Los Angeles County

The Threat: A Local Virus Outbreak is One Bite Away

There have been travel-related cases of dengue and chikungunya in and near areas that are known to have Asian tiger mosquitoes in Los Angeles County. If conditions are right, this can expose communities to local outbreaks.

By reducing the population of Asian tiger mosquitoes, we reduce the threat of local transmission of exotic diseases like dengue  and chikungunya.

Zika virus

According to the CDC, there have been reports of a correlation between microcephaly and Zika virus. Travel advisories are in effect for many countries in the Americas due to widespread Zika outbreaks. Get the latest information from CDC.

Symptoms include:

  • Fever
  • Rash
  • Joint Pain
  • Red eyes

There have been
Travel-related cases in California in the past 2 years

In 2015, CDC confirmed
of travel-related chikungunya cases in the U.S. were in California


Chikungunya (Chik-gun-GOON-ya) is a debilitating and painful, but rarely fatal mosquito-transmitted virus. Since 2013, there are 1.4 million reported cases from South America, the Caribbean and Mexico. In 2014, there were 50 confirmed cases of U.S. travelers coming back to Los Angeles County with the virus.

Yellow fever mosquitoes and Asian tiger mosquitoes can transmit chikungunya; both of these mosquitoes are present in Los Angeles County.

Symptoms include:

  • Painful joint / muscle pain that can last for several months
  • Fever

Most people (80%) bitten by an infected mosquito will get sick. There is no available vaccine for chikungunya. Read more about Chikungunya on CDC’s website. Learn more about how Chikungunya affected more than one million people around the world in the past few years — Science News. Note: The map in the article has not been updated to show that we, in California, have the mosquito that can transmit chikungunya.

Dengue fever

Dengue fever is only transmitted by mosquitoes from one infected person to another. Unlike West Nile virus, dengue viruses do not need birds or another host to transfer between people.

Yellow fever mosquitoes and Asian tiger mosquitoes can transmit dengue; both of these mosquitoes are present in Los Angeles County.

Symptoms include:

  • high fever
  • severe muscle / joint pain
  • mild bleeding

There is no vaccine for dengue. Read more about dengue fever on CDC’s website.

of the world's population, including people in LA County, are at risk of being exposed to dengue