How Mosquito Repellents Work

How mosquitoes find us:

Before we can understand how mosquito repellants work, we need to understand how mosquitoes find us in the first place.  Unfortunately for us, mosquitoes have evolved 3 ways of seeking out a meal. Each of these methods, used in tandem, enables them to fly in for the bite.

  1. 33 – 99 feet: At this distance mosquitoes rely on their sense of smell, specifically the CO2 plumes we, or other animals, emit.  Experiments have shown that the female mosquito only pays attention to the next cue once the first is present and they are closer to the source.
  2. 15 – 33 feet: The mosquito has homed in on the scent and at this distance is now searching for visual clues to spot you.  They are seeking the source of the CO2, not for a shape or body. 
  3. 1 – 3 feet:  The mosquitoes now rely on thermal sensory input to locate heat and moisture sources.  This prevents them from wasting time on objects such as a rock or vegetation.  

Mosquito repellents are designed to block the mosquito’s sense of smell in stage one.  This is important as it means that someone standing next to you, without repellent, will be attracting mosquitoes.  Of course, once the insect is within 33 feet of you, it now will not distinguish between you and your un-protected friend, meaning you are equally as likely to be bitten as they are.  We often hear people tell us that mosquito repellents don’t work. This is not necessarily true and is more a factor of those around you, as well as how well the repellent has “stuck”.  For example, if you are out in the yard with your spouse, and they just happen to sweat a lot, the repellent may have run off them. Hence, they are the magnet bringing them in to bite you.

What repellents do:

So how do repellents work?  DEET was developed by the military over 50 years ago but it was only more recently that studies have been done to understand exactly what it does.  Mosquitoes smell with their antennae, which are covered in olfactory nerves. The nerves are essentially equipped with odor receptors, that bind to odor molecules and trigger neural activity.  Simply put, DEET binds to these receptors leaving the mosquito confused and unable to smell you. The DEET over-activates the receptors rendering their ability to smell useless. 

According to many studies, the only repellent that comes close to the ability of DEET is lemon eucalyptus oil with the caveat that natural products break down faster and thus must be applied more regularly.  It should not be applied in its pure form and is also not recommended for children under the age of 3. Do not confuse it with the essential oil of lemon eucalyptus either (easy to do). Lemon eucalyptus oil has a different mode of action, simply creating a powerful smell to override that of CO2.  

The market is saturated with alleged mosquito repellents.  Wearables have become popular, although scientific studies show they are not capable of repelling mosquitoes.  Many people prefer to stay away from DEET and make natural repellents. We wrote a blog about DIY repellants recently and you can check out more here. However, they have not been proven to be effective in the fight against mosquito bites.  Folks also like to burn citronella candles and burn tiki torches, but these again will only confuse and delay you being found. 

It’s not enough to wear repellent in your own yard.  The most effective way to avoid or reduce the bites in your own yard is to remove all stagnant water sources from it.  Remember, one small capful of water is enough for 300 eggs. The more water you remove the better you will be. Of course, calling us to manage that water and treat your yard is the best way we know to make your outside fun.  Then you can ditch the repellant and just enjoy.


What is a Mosquito Misting System

Controlling mosquitos in your property is based very much in science.  However, choosing from the many mosquito control options and applying them can be somewhat of an art.  Mosquito Barrier Treatments are custom applications, performed by a licensed pest control technician, that conform to the intricacies of each individual property.  They take into consideration the mosquito pressure from outside of the property, breeding areas within the property, and vegetation and landscaping in and around the property; all with consideration of the areas of human activity where the mosquitoes need to be controlled. 

Some properties seem to be better suited for Mosquito Misting Systems.  It is estimated that about 5% of the properties in the NW Houston and S Brazos Valley area may actually get better mosquito control from one of these systems.  Many of these properties have smaller back yards with little or no barrier to adjacent properties by either vegetation or privacy fencing.  A good example is a golf course property, where there is nothing between the vast expanse of the course and the home.  

Like the Mosquito Barrier Treatments, installing a Mosquito Misting System is an art.  There has to be consideration for future vegetation growth, prevailing winds, times and areas of human activity, and locations of areas of high mosquito pressure.  These systems are a much more permanent option so carful design is a must.  Once the system is installed there have to be decisions on misting times and durations, to provide the greatest impact to the mosquito population with as little pesticide use as possible.  It is recommended that a licensed pest control technician design, install, maintain, and fill your mosquito misting system.  

What is a Mosquito Misting System?

 Simply it is a device that stores a product used to control mosquitoes.  It has a pump that is controlled by a timer.  At preset times of the day, a diluted solution of the pesticide is pumped through small tubing to areas within a property and dispersed through misting nozzles creating a very fine mist. This mist lands on areas where mosquitoes live, killing adult mosquitoes.  These systems can also be designed and installed to control spiders around the eaves of your home.  

I have a Mosquito Misting System and I’m still getting bit.  Why?

 Mosquito Misting Systems have to be maintained.  Clogged nozzles and dirty filters can cause your system to not work at peak performance.  A regular maintenance schedule is a must.  Also, if you’ve added landscaping or your landscaping has matured since the system was installed, it may need an upgrade.  Sometimes this can be as simple as adding tubing and nozzles to areas that are lacking in coverage.  Occasionally, a property can benefit from using a different product in the tank. Mosquito Joe can provide maintenance and expand your system, even if we didn’t install it. 

There are times when some larger properties will benefit from regular Barrier Treatments that can treat areas outside of where the misting system is.  This combination treatment can certainly take care of those pesky mosquitoes and allows us to control your biggest source; standing water.

Should I have a Mosquito Misting System installed or have Mosquito Barrier Treatments?

The only way to know is to have a Licensed Pest Control company evaluate your property.  Mosquito Joe provides Mosquito Barrier Treatments and installs and maintains Mosquito Misting Systems and can evaluate any property as well as give the pros and cons of both.

Which option is more expensive?

That’s a tough question.  There are so many variables involved that there is not one answer that fits every property.  

A misting system has a greater up-front cost.  Typical systems for smaller properties average from $2200 to $2800 to install.  Fills and maintenance make up the ongoing cost and generally occur every couple of months depending on the number of nozzles, number of mist cycles a day, and the length of each mist cycle.  Mosquito Barrier Treatments are a service and require no up-front costs.  Treatments are applied every 3 weeks (2 weeks for botanical and all-natural services) by a pest control technician, and include larvicide application in standing water, organic applications to flowering plants and vegetable gardens, and a barrier spray to all foliage.  Mosquito Joe will always provide a free quote for either and can help you decide what is the best option for your property.



Mosquito Bite – Now what?

What to do after you get bit by a mosquito

To understand the best way to deal with a mosquito bite it is helpful to first appreciate what is going on in our body when bitten.  And using the term “bite” isn’t entirely accurate.   

Firstly, it is the female mosquito who “bites” as she needs to take a blood meal so she has the protein required to lay eggs.  Every time you are bitten by a mosquito you know you just played a role in a birth of 300 or so mosquito eggs (and the resulting larvae).  The female lands on your body, having located you by your CO2 plumes, and pierces your skin with her proboscis, formed out of 6 needles with sharp teeth on two of them.  These teeth are so sharp that you can’t feel this process as she slices into your skin in search of a blood vessel. 

Once under the skin, she releases a vasodilator to keep your blood flowing while she is feeding.  For a fascinating look into the process, check out this video.  The vasodilator is contained within the saliva of the mosquito, along with all those virus’s we worry about.  In other words, once she is under your skin she will “spit” into you, both numbing and dilating the area to ease her meal.  The proboscis is very flexible, allowing the mosquito to move around under our skin without having to withdraw and start again.  You can watch some incredible footage of this here and here.  On average, a mosquito will drink for about 4 minutes, sucking so hard that the blood vessel can collapse or rupture into the surrounding area. Once she has taken her fill she will withdraw and fly away, without you being aware. 

Image of a mosquito bite on a man's handIn response to the injection of a foreign substance (saliva), our bodies mount an immune response.  Histamines are released around the site, causing swelling and that itch that we are all so familiar with.  It is thought that our sensitivity to bites decreases over time, which is why children often have much more substantial reactions to bites than adults.  There are also people who suffer from “skeeter syndrome”, an exaggerated reaction to mosquito saliva, better understood as a severe allergy to mosquito bites.  We have some customers whose children get welts from mosquito bites and use our service to help keep them healthy and playing outside. 

So, what can you do?  Obviously, your best defense is a good offense.  Using Mosquito Joe will keep your yard 95% mosquito resistant.  Using a repellent when leaving the house will also reduce your potential for bites and control that mosquito population in your yard by dumping water after rains and keeping you gutters free of debris.  Remember water = mosquitoes.  Most species come out at dawn and dusk so keep timing in mind when heading outside. As for a “mosquito season”, it is important to remember that mosquitoes will only hibernate when the temperatures remain under 55 degrees for a week, or we have 3 deep freezes in a row.  In the 4 years that Mosquito Joe has been treating in NW Houston and South Brazos, we have only had one week where these conditions have been met, meaning mosquitoes are always out. 

But let’s talk about what you can do once the bite has happened.  In the case of a normal reaction, calamine lotion or a topical anti-itch lotion can help.  You can also take an oral antihistamine such as Benadryl or Claritin.  If you have children who react more strongly using an ice pack can help with swelling and the itch.  Home remedies, including a warm oatmeal bath, can help as well, but garlic and other suggestions won’t do the trick, so stick to simple options.   

Mosquito bites can result in complications, from welts and blisters to sepsis.  The diseases they carry include malaria, West Nile, Zika and meningitis. If you experience a rash, fever over 101, persistent headache, muscle or joint pain or difficulty breathing, seek medical help.  Customers of ours who have West Nile tell us that they never understood the implications of the disease until it was too late.  While we are used to mosquito bites, we should never become complacent about the implications they carry.   

Mosquito Joe of NW Houston & S Brazos Valley 



7 DIY mosquito repellants

Homemade Mosquito Control

While DEET has long been the recommended go-to for warding off mosquitoes, there are many who prefer an all-natural, homemade option, particularly when they are applying the repellent to their children.  We have some options for you but caution you to remember that all-natural options wear off quickly, so be prepared to re-apply every couple of hours.  Also, please remember that essential oils can trigger skin reactions, particularly in the young, so please do a patch test before using.  Finally, essential oils degrade quickly in sunlight, so it is a good idea to store your homemade repellant in a dark, well labelled bottle in a dark location.  

Mosquitoes, specifically female mosquitoes, bite when they are preparing to lay eggs.  They need the protein to lay and have an uncanny ability to find us from our CO2 plumes.  Repellants are exactly that – they repel the mosquito rather than making us “invisible” to them.  Mosquitoes are put off by certain smells, particularly garlic, although we promise we do not suggest you slather yourself in garlic before leaving the house! 

While mosquito repellant plants don’t really exist (you can check out an earlier blog post for more on that), the fragrance from certain plants, when ground down to the oils, will put mosquitoes off.  These include essential oils from lavender, catnip, eucalyptus, lemon grass and other “mosquito repellant plants” (AKA plant oils).

In all your recipes you will want to combine your essential oil with a carrier oil (Olive, Almond, or Grapeseed are good choices) at a 100 drop to 2 tablespoon ratio.  To preserve your recipe, you will need an alcohol, which you can add at a ratio of ½ teaspoon to 2 Tablespoons of oil.  Isopropyl alcohol or vodka are good options to use.  You will also want to add in some witch hazel.  If you have it lying around (and who doesn’t) a teaspoon of vegetable glycerin will help keep everything combined and reduce settling if you want to try using water instead of oil (we don’t find this to be as effective, especially in our heat and the resulting sweating).  Now for the recipes!  


2 tablespoons of oil 

100 drops of essential oils 

½ teaspoon of alcohol 

½ teaspoon Witch Hazel 

1. Herb garden:  Add 50 drops of basil and 50 drops of rosemary essential oils 

2. Citrus: 100 drops of lemon grass, or orange, or a combination of both 

3. Geranium: 100 drops 

4. Lavender: 100 drops 

5. Mint:  100 drops 

6. Eucalyptus: 100 drops 

7. Citronella: 100 drops (caveat here, as we acknowledge that this may not be what you want to smell like!) 

You can get inventive with your recipe but don’t lose sight of the fact that we are trying to repel mosquitoes, not delve into perfumery. 

If you would like to keep some stand-by’s available for camping trips or to keep in your car, homemade options may not be a good idea.  Sunlight and heat will degrade them.  We recommend you visit the EPA website for more guidance on skin repellents.  They also have an excellent search tool for finding the one that is right for you.  

If your mosquito issue isn’t limited to camping trips, but instead closer to home in your back yard, we can help.  We offer an all-natural service for your yard to keep those mosquitoes away using a combination of garlic (you won’t notice the smell, but the mosquitoes will!) rosemary and mint.  Even our combination services rely on garlic around flowering plants, as we are very focused on protecting our pollinators and minimizing our impact in a yard.  We want the mosquitoes out, along with their diseases, while keeping birds, butterflies and all other wildlife happy and content.  

Finally, as we cannot harp on about it enough, remember that your number one source for mosquitoes is water.  Just one teaspoon is enough water for them to breed in and managing that is a vital part of what we do.  If you want to reduce the numbers in your yard clean your gutters, remove all containers and dump out water after it rains.  If you want to learn more about our service don’t hesitate to give us a call.  We are always happy to talk mosquito! 🦟