Mosquito Control Product Recommendations

 

 

What works? (and what doesnÕt)

 

Larvicides are added to standing water to keep mosquito larvae from reaching adulthood

 

CC Bacillus thuringiensis var. israelensis (Bti) – a naturally occurring soil bacteria that selectively targets mosquitoes, deemed eco-friendly[1]. Recommended by the Fairfax County Health Department. There have been some cases reported of mosquitoes developing a resistance to Bti, but it is generally a very effective larvicide. It is sold as Mosquito Dunks, VectoBac, Aquabac and Bactimos.

 

C s-Methoprene – a chemical that mimics a juvenile insect hormone, disrupting the larvae ability to mature, used in some areas (usually within a government program) to control mosquito breeding in catch basins[2]. According to the EPA, S-Methoprene is not harmful to mammals (it is used in products like Frontline for pets), is safe for humans, but has limited toxicity to some fish and aquatic creatures, particularly if used in higher than recommended concentration. It is non-toxic to bees1. It is sold as PreStrike Mosquito Larvicide granules.

 

Insecticides, also known as insect adulticides  - neurotoxins that kill adult mosquitoes

CC Permethrin is that can be used on clothing and fabrics or on tents and mosquito nets. It is also sold for use as a perimeter spray for yard and plants. One benefit is each application can last for over 2 weeks, even through launderings3. Careful use is advised, as this chemical is also toxic to beneficial insects as well as fish and honeybees when sprayed[3],[4]. It should not be used near streams. Permethrin as a pyrethroid, a chemical that acts on the nervous system; but is generally safe when used according to the label instructions3.

 

C D-Allethrin[5] – products like ÒThermaCellÓ (sold at Home Depot) use this endocrine disruptor to kill mosquitoes. It is an effective insecticide, but mosquito repellant products offer limited protection depending on placement. It is highly toxic to fish and honeybees.

 

Mosquito traps, baits, and other devices

D Bug Zappers – not effective for killing mosquitoes[6]. Research has shown that only1% to 4%

       of insects killed by bug zappers are mosquitoes[7] and those are mostly ÒaccidentalÓ kills. This is because mosquitoes are not attracted to ultraviolet light that zappers use to lure insects[8]. Unfortunately, the zappers kill beneficial insects that control garden pests.

 

C Carbon Dioxide emitting traps. Manufacturers of these devices boast studies showing the units attract large numbers of mosquitoes. The most effective use a combination of lures; carbon dioxide, heat, scent (Octenol for Culex mosquitoes or Lurex3 for Aedes-Asian Tiger mosquitoes). Traps that do not use a combination of lures are generally not effective[9]. The traps must be placed near the breeding source, where they attract then trap using a fan that sucks the insect into a container. Research testing shows that even though the devices trap a lot of mosquitoes, areas as close as just 15 meters away show no decreased numbers of mosquitoes[10]. Still, this may be a good option, especially for yards that back to parkland. One trap frequently recommended is the Mosquito Magnet[11]. Note that Lurex3 has not been around long enough to be tested extensively, but Joshua Smith of Fairfax County Health DepartmentÕs Disease Carrying Insect Program tells me he expects testing to confirm its effectiveness against Asian Tiger mosquitoes. The biggest drawback to these devices is the price – most run $300 and up.

 

DD Ultrasonic devices that claim to mimic sounds that repel mosquitoes are not effective7.

 

CC Citronella candles will not eliminate mosquitoes, but are proven effective repellants. They are inexpensive and readily available. Regular unscented candles will also repel mosquitoes, but are only half as effective[12].

                         

DD Plants such as citronella grass, citrosa, lemon thyme, lemongrass, peppermint, have been reported to have mosquito-repellant abilities. The essential oils from many plants do have repellant properties. But the plants would need to be crushed to release the oils, and then you would need to rub the oils on your skin to repel mosquitoes. The general rule is: if you really like the plant, make it part of your landscape4,[13]. But donÕt get it as a mosquito solution because you will be disappointed.

           

DD    Edible supplements like garlic or thiamine (vitamin B1) have never been found effective[14].

 

My best adviceÉ

A multi-pronged approach is the best way to beat mosquitoes. Personal protection with a product such as OFF!, SawyerÕs or Repel Lemon Eucalyptus, plus citronella candles, larvicides and  possibly a mosquito trap will make your yard livable this summer, and help to keep you safe from West Nile Virus and other mosquito borne diseases.


[1] Environmental Protection Agency, 2007. Larvicides for Mosquito Control. Retrieved from http://www.epa.gov/opp00001/health/mosquitoes/larvicides4mosquitoes.htm

[2] Butler, M., Lebrun, R.A., Ginsburg, H.S., Gettman, A.D., 2006. Efficacy of Methoprene for Mosquito Control in Storm Water Catch Basins. Journal of the American Mosquito Control Association, 22(2).

[3] Department of Health and Human Services, Agency for Toxic Substances and Disease Registry. 2005. Toxicology Information About Insecticides Used for Eradicating Mosquitoes (West Nile Virus Control). Retrieved from http://www.atsdr.cdc.gov/consultations/west_nile_virus/permethrin.html

[4] Cox, C. (1998). Permethrin. Journal of Pesticide Reform,18 (214l). Obtained April 15, 2008 from www.safe2use.com/poisons-pesticides/pesticides/permethrin/cox-report/cox.htm

[5] PAN Pesticides Database: Chemicals. Retrieved from http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC34825#Toxicity

[6] Peairs, F.B., Cranshaw, W.S., 2007. Mosquito Management. Colorado State University Extension – Horticulture. Retrieved from http://www.ext.colostate.edu/PUBS/INSECT/05526.html.

[7]Crans, W.J. Products and Promotions That Have Limited Value for Mosquito Control. Retrieved from http://www.rci.rutgers.edu/~insects/proprom.htm

[8] Freudenrich, C. How Bug Zappers Work. Retrieved from http://home.howstuffworks.com/bug-zapper.htm

[9] Compare MosquitoTraps.com Find mosquito traps and reviews for mosquito control plus tips on trap alternatives. Retrieved from http://www.comparemosquitotraps.com/megareview.htm

[10] Brown, H., Paladini, M., Kline, D., Barnard, D., Fish, D. 2008. Surveillance and Ecology of Mosquito, Biting and Filth Breeding Insects. Submitted  and accepted for publication by the Journal of Medical Entomology. Retrieved from the USDA Agricultural Research Service at http://www.ars.usda.gov/research/publications

[11] ÒMosquito HygieneÓ throughout the Life Cycle of Culex Mosquitoes, 2002, Cornell University Center for the Environment, retrieved from http://cfe/cornell.edu/ERAP

[12] Fradin, M.S., 1998. Mosquitoes and Mosquito Repellents: A ClinicianÕs Guide. Annals of Internal Medicine, 128(11)

[13] Compare Mosquito Traps.com. What are the natural and plant-derived mosquito repellents. Retrieved from http://www.comparemosquitotraps.com/natural.htm

[14] Fradin, M.S., Day, J.F., 2002. Comparative Efficacy of  Repellents against Mosquito Bites. The New England Journal of Medicine, 347(1)