Who to Call About Mosquitoes in L.A., and Who Handles the Rats

Seven agencies split the county, the one covering your block is already paid for, and most do mosquitoes and nothing else.

The mosquitoes biting you at dusk are somebody's job, and it probably isn't the city's. Seven public agencies divide Los Angeles County between them for mosquito control: five independent districts and two city health departments. The one that covers your address will send a technician to your yard for nothing, because you already paid for it on your property tax bill. What it won't do, across most of the county, is touch your rats. Or your bees.

This is a bad year to guess wrong about the number. Los Angeles County's Department of Public Health has documented 135 West Nile virus infections and five deaths so far in 2026, according to Report #8 of its weekly arboviral epidemiology series, dated September 25. A hundred and thirty of those people had symptoms, and the most recent illness began on September 11. About a quarter of the infected live in the East Los Angeles County area, another quarter in the South Bay and about a fifth in the San Fernando Valley.

The state's running count says something smaller. California's statewide case-count table, updated Fridays, had Los Angeles County at 86 human cases as of September 25 — 86 of the 210 confirmed statewide. The county's report explains the gap without being asked: the state's tally "does not include all of the Los Angeles County infections due to reporting lag." The same report relays the state's own assessment of the season, which is that California is seeing its highest levels of West Nile activity in five years. Neither number is wrong. One is further behind.

The district covering the largest share of the county published a warning on Monday. The Greater Los Angeles County Vector Control District said it had found 384 West Nile-positive mosquito samples this season against 104 at the same point last year, and 78 positive dead birds against two, and blamed "an extremely mild winter where rainfall was interspersed with unusually warm weather."

Seven agencies, and the one line that decides which is yours

We pulled the county Department of Public Health's own referral list and counted the agencies on it: five independent special districts, plus the health departments of Long Beach and Pasadena, which run their own programs. The boundaries don't follow anything you'd recognize — one of them splits the City of Los Angeles and another splits Long Beach three ways — and the only countywide map of them is a scanned PDF the county still links from that page. Here is the roster, with what each one will and won't do.

Greater Los Angeles County Vector Control District — (562) 944-9656. Formed in 1952 as the Southeast Mosquito Abatement District, by citizen petition, over mosquitoes coming off the Los Angeles River. It now covers 36 cities and unincorporated stretches, nearly six million residents across more than a thousand square miles, which makes it the default answer for most of the county. Its referral page says it "only provides services for" mosquitoes, midges and black flies, and it means only. Service requests go through a form on its site; the office is at 12545 Florence Avenue, Santa Fe Springs.

Los Angeles County West Vector and Vector-Borne Disease Control District — (310) 915-7370. The Westside and the South Bay: Agoura Hills, Beverly Hills, Calabasas, Culver City, El Segundo, Hawthorne, Hermosa Beach, Hidden Hills, Inglewood, Lawndale, Lomita, Malibu, Manhattan Beach, the four Palos Verdes cities, Redondo Beach, Santa Monica, Torrance, West Hollywood, Westlake Village, the western portion of the City of Los Angeles and unincorporated pockets in between. Of the five districts, this is the only one whose published mandate runs past mosquitoes: ticks and Lyme disease, red imported fire ants and Africanized honey bees are all on its list. Counter at 6750 Centinela Avenue, Culver City.

San Gabriel Valley Mosquito and Vector Control District — (626) 814-9466. Twenty-six cities and more than 1.5 million residents, from Alhambra and South Pasadena east to Claremont and Pomona, running since 1989. It is the bluntest of the seven about its limits, naming bees, rodents, cockroaches, fire ants and common house flies as somebody else's job, and it puts the typical resident's share of the cost at $20.00 a year. Headquarters at 1145 N. Azusa Canyon Road, West Covina.

Antelope Valley Mosquito and Vector Control District — (661) 942-2917. Formed on August 21, 1958, and now covering more than 287 square miles — Lancaster, Palmdale and Quartz Hill — up from the 178 it started with. Surveillance, control, mosquitofish and school presentations are all free, paid for by a benefit assessment charged to every parcel inside the district, which the district gives as the reason it can serve "the entire community" without charging at the door. Office at 42624 6th Street East, Lancaster.

Compton Creek Mosquito Abatement District — (310) 933-5321. The smallest and the oldest. Compton residents voted it into existence in 1927, and it now covers 12.5 square miles and close to 100,000 people. It runs a voluntary pool reporting program, and says its services are funded by tax dollars and provided at no charge. Office at 1224 South Santa Fe Avenue, Compton.

City of Long Beach, Department of Health and Human Services — (562) 570-4132. Long Beach is where the county's map gets strange. The city's Bureau of Environmental Health handles vector control inside the city "with the exception of areas east of Lakewood Blvd" — those belong to Greater Los Angeles — and a small piece of the northwest that belongs to Compton Creek. One city, three agencies, and the dividing line is a boulevard. It is also the only agency here that names rodents alongside insects in its own description of the work, it takes mosquitofish requests on a form, and it says to call 911 for an emergency swarm or hive.

City of Pasadena Public Health Department — (626) 744-6005. Pasadena runs its own health department and gets its own line on the county's referral list. It is also one of the 26 cities the San Gabriel Valley district names in its service area, so Pasadena has both. The arrangement shows up in the county's weekly West Nile report, whose table of cities with reported infections carries a one-line footnote: "Excluding Long Beach and Pasadena." The two cities that run their own health departments are the two the county's own case table can't see.

The same bee, two different answers

If a swarm settles under your eaves, what happens next depends on which district you are standing in, and the difference is not a matter of degree.

In Greater Los Angeles's territory, which is most of the county, the district sends you to the Los Angeles County Agricultural Commissioner/Weights and Measures at (626) 575-5471, or to its bee hotline, 1-800-BEE-WARY — 1-800-233-9279. The Agricultural Commissioner's own bee page routes a nuisance complaint to an online form and publishes a Feral Bee Removal Referral List, which is a list of people you can hire.

In Los Angeles County West's territory, the district comes out. Its bee control program says Africanized honey bee swarms and nests "are removed when requested by citizens or emergency response units who feel their safety or the public's safety is in jeopardy," and the work doesn't end with the nest: technicians set pheromone-baited remnant traps for the bees that were out foraging, then return the next day and collect them. Same county, same insect, and the boundary between those two answers runs through the City of Los Angeles itself.

Rats belong to no district at all

The mosquito districts don't take rodent calls — Greater Los Angeles and San Gabriel Valley both say so in print — and the referral goes to the county's Vector Management Program at (626) 430-5450, in Baldwin Park; the county's own page for that program sits under Public Health's Environmental Health division and gives the general line as (888) 700-9995, which is also the number for a live animal that needs collecting.

You're wondering whether that covers your address. It may not. The county page draws its own boundary in a sentence: Environmental Health is responsible for properties "within unincorporated areas and cities that have adopted the County's ordinance" — and it doesn't publish the list of cities that did. Long Beach is the visible exception, because its vector specialists handle rodents inside the city themselves. Everywhere else, the honest instruction is to call (888) 700-9995 and ask whether your street is theirs before you wait on an inspector.

The rest of the referral list is short and worth keeping. Sick or dead birds go to the state at westnile.ca.gov. Sick or dead bats go to county Public Health. Mold goes to the state health department. Coyote sightings have their own form at the Agricultural Commissioner. Everything else — ants, cockroaches, termites, bedbugs — is a private exterminator, and none of the seven will pretend otherwise.

What free actually buys, and the fish

Free here means a licensed technician on your property, not a coupon. The districts inspect, they treat standing water, they trap and test mosquitoes, and they hand out fish.

Mosquitofish are the service most people have never heard of, and the mechanics differ enough between districts to matter. Los Angeles County West gives them over the counter: 6750 Centinela Avenue, Monday through Friday, 9:30 a.m. to 3 p.m., free to district residents for their own property. Greater Los Angeles does no counter pickup at all — you file a service request first, the district decides whether fish are the right answer for your water, and "a technician must make the placement." Both warn off koi ponds, because the fish don't cohabit. Long Beach takes them on a request form of its own.

They are worth the errand. A mosquitofish eats up to 100 larvae a day, bears 50 to 100 live young a brood, and breeds right through the summer when the mosquitoes do. They go in ornamental ponds, fountains, water gardens, animal troughs and unmaintained pools, and never into a creek or a storm channel.

Which brings up the thing the districts most want reported. A neglected swimming pool is the single most productive mosquito habitat in this county, and Greater Los Angeles puts a number on it: "a single 'green' swimming pool can produce up to 3 million mosquitoes in one month." The district will treat one with a short-term pesticide for up to six months while the owner restores it, and it checks pools that have been drained dry as many as four times a year, accepting a photo in place of a visit. Compton Creek runs its pool reporting program on the same logic. The pool does not have to be yours.

You already paid for this

Every district on this list is funded the same way, out of your property tax bill, and each one publishes the arithmetic. Greater Los Angeles is paid by ad valorem property taxes plus a special assessment on each parcel, set by land use and lot size; the minimum it posts for a single-family home is $14.67, for fiscal year 2019-20, with another 33 cents on parcels inside the black fly control zone. That is the most recent figure the district publishes. San Gabriel Valley gives $20.00 a year. Antelope Valley and Compton Creek both describe a parcel assessment as the reason their work carries no charge at the point of service.

So the call isn't a favor anyone is doing you. It's the only part of the transaction you haven't completed yet.

The order to do it in

Find the agency first, because every other answer follows from it. Greater Los Angeles puts a Find Your Agency link at the top of its referral page, and it names the other districts underneath; the county's Environmental Health page lists all seven phone numbers on one screen if you would rather just read them.

Then: mosquitoes, midges or black flies, call your district and expect an inspection. A green pool, yours or the one over the fence, same call. Bees, (310) 915-7370 if you are in the west district and 1-800-233-9279 if you are not. Rats, (888) 700-9995, and ask about your city before you wait. Repellent, per the district's September 28 notice, at least 15% DEET, picaridin, IR3535 or oil of lemon eucalyptus — there is no human vaccine for West Nile, which is why that notice ends on a bottle rather than a shot.

And if you find a dead bird, report it at westnile.ca.gov/report.php. Those reports are, in the state's words, "one way of tracking where WNV could be spreading," and the state has logged 148 West Nile-positive birds in Los Angeles County this year.

Agency names, service areas, phone numbers, addresses, hours, fees and assessment figures above were checked on September 29, 2026 against the Los Angeles County Department of Public Health's Vector Management Program page and its Report #8 of the 2026 West Nile Virus and Other Arboviral Diseases epidemiology series (September 25, 2026); the California Department of Public Health's statewide West Nile case-count table; and the published pages of the Greater Los Angeles County, Los Angeles County West, San Gabriel Valley, Antelope Valley and Compton Creek districts, the City of Long Beach Bureau of Environmental Health and the Los Angeles County Agricultural Commissioner/Weights and Measures. District boundaries and phone numbers change, and the sources linked above win over this page. It is re-verified and updated in place at this address.