Health & Medicine

Here’s what you need to know about West Nile aerial spraying in Elk Grove, Pocket area

Here are the planes and the plan for Monday night’s aerial insecticide spraying

Three aircraft will be used for aerial insecticide spraying over south Sacramento neighborhoods and Elk Grove on Monday evening, July 23. The spaying will target mosquitoes where high levels of West Nile virus have been discovered.
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Three aircraft will be used for aerial insecticide spraying over south Sacramento neighborhoods and Elk Grove on Monday evening, July 23. The spaying will target mosquitoes where high levels of West Nile virus have been discovered.

In an effort to target and kill mosquito populations, aerial spraying will take place Monday and Tuesday nights in areas with intense West Nile Virus activity within the Sacramento region.

The Sacramento-Yolo Mosquito and Vector Control District has planned for spraying to begin at 8 p.m. both nights.

Luz Robles, a spokesperson for the district, answered questions from The Bee about the spraying.

Here’s what you need to know.

Q. When and where will spraying take place?

A. The spraying starts right after sunset — that is when mosquitoes are most active. The goal of the aerial applications is to reduce mosquito populations, so we want the applications to start at a time when mosquitoes are most active, which is around dusk. The spraying will take place over that area of concern, on the map that we have on our website (which) includes the area of the Pocket neighborhood, south of Fruitridge Road as well as the city of Elk Grove.

Q. How will residents know whether their neighborhoods will be sprayed?

A. We have an interactive map on our website. If you go to, we have a link there that has all the important information regarding the aerial spraying. We have a map that shows a spray bloc and you can actually type in your address and it’ll show you if you’re in the spray bloc or not. We also have the map of all the West Nile Virus activity, so people can actually see the intensity of the virus. (There are) pins that show the dead bird and mosquito samples and where they were collected … the date they were collected and the species of bird. Or, if it was a mosquito, the species of mosquito. You can very much see why there’s such big problems throughout the Pocket and Elk Grove.

Q. What can residents expect during the spraying?

A. During the spray, people will be able to see and hear the planes. We have three different planes that will be flying in different parts of the spray bloc. The planes fly at about 300 feet. While we give the time (frame) up until midnight … it starts around dusk and it ends by about 10:30 or 11. One good way to find out when the spraying starts and stops is (by signing) up for text spray notifications. They can get those updates by texting the word, ‘sprayupdate’ to the number 69922. That automatically signs you up for the spray notifications. We will tell you when the spraying starts and when the spraying ends on both nights.

Q. How did the Vector Control District determine aerial spraying was necessary?

A. We determined that the aerial spraying was necessary based on careful consideration and an evaluation of our surveillance results. As of last Friday, we determined 23 more mosquito samples within that whole area tested positive, and that was in addition to the 27 that had tested positive on Wednesday. Over the past few weeks, the virus had been escalating and on Friday, when we received the latest round of results, most of the positive mosquito samples were from that area of concern.

Q. What insecticide will be sprayed?

A. The insecticide is called Trumpet (EC). ... There are only a few classes of material registered for use in mosquito control and this is one of them. It’s targeting the adult flying mosquitoes. And it kills the mosquitoes on contact. At the very low dosage rate of 0.75 ounces per acre, it only affects mosquitoes and insects smaller than mosquitoes.

Q. Are there any health risks for humans associated with the insecticide?

A. No, this is a material that has a use routinely in mosquito control in many thousands of acres throughout the United States in low dosage rates. There’s no adverse health risks for humans, pets or the environment.

Q. What should residents do while the aerial spraying is occurring?

A. There’s no necessary precautions that they need to take. We always say if it makes them feel better to be indoors, that’s great. If they want to close their windows, that’s fine as well. But there are no necessary precautions that need to be taken during the spray. The material breaks down very quickly and it’s dispensed in very fine aerosol droplets, that are only designed to kill mosquitoes and insects smaller than mosquitoes.

Q. What are the primary concerns you’ve heard from locals about the spraying?

A. We were out at an event on Friday evening in the Pocket answering people’s questions and the majority of people (are) very grateful we’re doing the spraying — they’ve noticed a lot of mosquitoes around the Pocket area, they’re being bothered by the mosquitoes, they know that West Nile Virus is a risk. We do have some concerned residents, and we completely understand. I think a lot of times people think West Nile Virus is not a concern; they’re wondering why we’re doing this if there’s not a lot of human cases. But that’s exactly what we’re trying to prevent. With this … application of the aerial spraying, we’re trying to reduce the population of mosquitoes that can pose a threat to public health.

Q. How is the Vector Control District getting word out to residents?

A. We’ve been working very closely with the neighborhood associations and we’ve disseminated information via all of our social media outlets. We’ve emailed directly to the neighborhood associations in that area, in the Pocket as well as Elk Grove. We’ve posted on Nextdoor. We also ran targeted social media ads, targeting specific ZIP codes within the spray blocs and we’ve worked very closely with the city. For example, the city of Elk Grove public information officer tweets that information out.

Q. What else should residents be aware of?

A. We encourage everyone to sign up for the spraying notification. Whether it be any ground treatment we’re doing or an aerial treatment, that’s the best way of finding out. We would send you a notice if we’re going to be doing any work in your ZIP code.

Robles added that due to the time of the spraying, bees and other beneficial insects will have returned to their hives and will not be affected by the spraying.

The Trumpet EC insecticide is also EPA registered. According to the EPA’s pesticide product label for the insecticide, Trumpet EC can be used for treatment on shrubbery and vegetation with mosquitoes, including residential areas, woodlands, pastures and feedlots.

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