Mosquitoes are a common summertime nuisance that can be bothersome and even dangerous due to their ability to spread diseases like malaria, yellow fever, dengue fever, and Zika virus. While there are many commercially available sprays, lotions, and devices marketed to repel mosquitoes, many claim that certain colors and wavelengths of light can also deter these pesky insects.
How do mosquitoes use vision to find hosts?
Mosquitoes rely heavily on vision to locate hosts to bite and consume blood from. They are particularly attracted to heat, carbon dioxide, and certain colors and contrasts. Mosquitoes have specialized visual receptors in their eyes that help them locate warm-blooded hosts from distances up to 50 meters away.
Most mosquitoes are believed to see colors differently than humans do. They have receptors that are attracted to specific wavelengths of light. Some of the colors that entice mosquitoes include:
- Red – reminds them of blood vessels under your skin
- Orange
- Black – contrasts well against human skin
- Dark blue
On the other hand, some colors are believed to deter mosquitoes, as they do not trigger their prey-seeking instincts. These include:
- Light/pale green
- Purple
- Silver
- White
- Light yellow
Wearing clothing in these colors may help you go undetected to some extent. Specific wavelengths of light also seem to confuse and repel the insects.
Does color really make a difference for mosquito deterrence?
There has been some scientific research into how mosquitoes respond to different colors. However, the results are not always consistent. Here is a summary of some key findings:
- Multiple studies found more mosquitoes landed on surfaces colored black, red, and navy blue compared to lighter and more reflective colors like green, purple, and white.
- One study found that Aedes aegypti mosquitoes were most attracted to the color red, followed by orange, black, and cyan. They were least attracted to purple, white, and green.
- Another experiment found that Anopheles mosquitoes were drawn the most to black and red. Lighter colors like white, yellow, and green did not attract them as much.
- A study in Mali found that sleeping under a light blue bed net led to significantly fewer mosquito bites compared to white, light green, red, and black nets.
- However, other research suggests color may not make a major impact compared to factors like a person’s body temperature, carbon dioxide output, sweat, and scent.
So while mosquitoes do seem drawn to certain colors more than others, it’s not a universal rule. Color preferences can vary between mosquito species. The overall attractiveness of a color also depends on other variables related to the person or animal the mosquitoes are targeting.
What are the best colors to wear to prevent mosquito bites?
Based on the research available, the following colors seem to be the best choices to wear when trying to avoid mosquitoes:
- Light green – This pale or minty shade of green appears to go virtually unnoticed to many mosquito species in scientific studies.
- Purple – Ranging from lavender to lilac, purple hues don’t seem to trigger attraction in mosquitoes.
- Silver or metallic – Shiny or reflective fabrics like silver, metallic gold, etc. can help conceal you.
- Blue – While dark blues attract mosquitoes, pale and light blues don’t appeal to them.
- Yellow – A very light, pale yellow rather than bright hues work best.
- Orange – Duller, darker shades of orange should be avoided. Brighter, neon oranges may be OK.
In general, the lighter and more reflective the shade, the less attractive the color seems to be for mosquitoes. Wearing clothing in these hues may provide some protection against mosquitoes, but it should be used in conjunction with insect repellent sprays, citronella candles, mesh screens, and other deterrents for best results.
Do bug zapper lights work for mosquito control?
Bug zapper lights are devices that use ultraviolet (UV) light to attract and electrocute flying insects that come near. The UV wavelengths produced by these traps attract a wide range of bugs, but they can help control mosquito populations to some extent.
Research on bug zappers shows:
- Mosquitoes made up about 4.2% of the overall insects collected by various bug zappers in one study.
- They are more effective at killing mosquitoes in smaller, confined spaces rather than outdoor areas.
- Bug zappers do attract and kill female mosquitoes, which are the ones that bite humans.
- They tend to be more effective at targeting larger mosquito species versus smaller ones.
While bug zappers can help curb local mosquito activity, they have some limitations:
- They do not attract mosquitoes as readily as carbon dioxide and other human outputs.
- Mosquitoes can develop resistance or aversion to the UV wavelengths over time.
- Outdoors, bug zappers only collect mosquitoes within a few feet of the device.
- The light can actually attract more mosquitoes into your yard than it kills.
So bug zapping lights may provide some localized control, but should be used along with an integrated mosquito management plan and more effective deterrents like window screens and citronella.
What colors of light are mosquito repellents?
Besides ultraviolet light, certain colors along the light spectrum in the 400 to 600 nanometer range have shown some mosquito deterrent effects. Here are some of the hues of light that may repel mosquitoes:
| Color | Wavelength |
|---|---|
| Green | 495-570 nm |
| Turquoise | 480-510 nm |
| Purple | 400-450 nm |
| Violet | 380-450 nm |
Research suggests these colors can deter mosquitoes because:
- They create a contrast effect against dark colors like black and brown that attract mosquitoes.
- The wavelengths interfere with their prey-seeking vision receptors.
- Some, like violet, mimic colors of flowering plants mosquitoes avoid.
Using light bulbs or other lighting that produces these spectrums of light may help make an outdoor space less appealing to mosquitoes. However, factors like light intensity and positioning also impact results.
Do citronella candles really repel mosquitoes?
Citronella candles contain oil from the citronella plant, a mosquito repellent. The candles release a fragrance that helps mask human scents. Research on citronella candles shows:
- Burning citronella candles reduced mosquito bites by 42% in one study using camping volunteers.
- Another experiment found almost 50% fewer mosquitoes in yards with citronella candles compared to controls.
- The repellent effect depends on having enough candles or torches to maintain an effective concentration of citronella fumes.
- Weather conditions also impact results – the scent vaporizes fastest and is most potent in warmer air.
Citronella candles seem to be effective for repelling mosquitoes, provided they are used properly. Tips for best results include:
- Place candles near seating areas, upwind of gathering spaces.
- Use enough candles or torches to saturate the air with citronella.
- Pair candles with ceiling fans or light winds to distribute the scent.
- Replace candles as needed to maintain scent levels.
- Use unscented candles at the same time to maximize the citronella effect.
Do mosquito repellent bracelets work?
Mosquito repellent bracelets are products that contain concentrated essential oils or synthetic versions. When worn, they gradually release an insect-repelling vapor to create a “barrier” around the wearer’s wrist.
Studies on the effectiveness of these bracelets have found:
- In one EPA field test, wristbands with 23% citronella reduced bites by 31% compared to placebo bracelets with no oils.
- Bracelets with higher (40%) citronella content provided over 90% bite protection in another EPA study.
- Synthetic “geraniol” bracelets blocked around 75% of bites vs. placebo in one study.
- A Consumer Reports test found citronella and geraniol bracelets ineffective against bites.
While early EPA research seemed promising, more recent independent testing has shown mosquito repellent bracelets to not be very effective:
- The repellent effect is limited only to the wrist area.
- Many bracelets are too low in oils to emit enough vapor.
- Natural weathering causes the product to lose potency quickly.
- Oils can cause skin irritation with prolonged direct contact.
Based on the available evidence, mosquito repellent bracelets do not seem to provide adequate protection from bites. Reliable insect sprays or lotions applied to exposed skin are a better option.
Conclusion
Mosquitoes rely heavily on vision cues to locate warm-blooded hosts to bite. Some colors like red, orange, and black strongly attract mosquitoes as they mimic blood vessels or contrast well with skin. Lighter shades of green, purple, blue, and yellow do not appeal to these insects as readily. Wearing pale-colored clothing can provide some degree of camouflage from mosquitoes, particularly in shades of green, lavender, silver, light blue, and light yellow.
Certain wavelengths and hues of light like green, turquoise, violet, and purple may also deter mosquitoes. Citronella candles can repel mosquitoes through scent effects, provided enough are used to saturate the air. Bug zapping lights attract and electrocute some mosquitoes via UV light, but have limitations. Overall, an integrated pest management plan using screens, repellent sprays, fans, and elimination of breeding areas is needed to effectively control mosquitoes around the home.
