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Mosquito Repellents That Work Against Zika Virus

Many people are against synthetic chemicals and will not consider products like DEET. As I have reported before in DEET- is It Safe?, DEET is quite safe but many still do not believe the facts.

In the last couple of weeks the Zika virus has been all over the news. The World Health Organization has declared Zika virus a ‘public health emergency’ of international concern.

Which mosquito repellents work best against Zika? Are any of the organic products recommended? It is time to have another look at the mosquito problem.

Mosquito Repellents That Work Against Zika Virus

Mosquito Repellents That Work Against Zika Virus

Mosquitoes Carry the Zika Virus

So far it is believed that Zika is only carried by Aedes mosquitoes, mostly the Aedes aegypti , but other Aedes species may also be involved. This mosquito only lives in warm climates – a good reason to live in Canada 🙂

There are hundreds of different mosquito species, and most repellents are not tested on very many of them. To better understand the effectiveness of a repellent for Zika, it must be tested on at least Aedes aegypti.

The best defense against Zika is to avoid being bitten. The CDC emphasizes that wearing long-sleeved clothing is important but that mosquito repellents are essential, too.

Testing of Repellents on Aedes Mosquito

Consumer Reports has just released their testing on Aedes mosquito with numerous products. To find the most effective mosquito repellents, they tested “products containing deet, a chemical called IR3535, as well as those containing two plantlike, but chemically synthesized, ingredients: lemon eucalyptus and picaridin. They also looked at repellents made with natural plant oils, such as geraniol, castor oil, soybean oil, citronella, and rosemary” (1).

Most of the findings were not a surprise.

The most effective products were synthetic chemicals that had a reasonably high concentration of the active ingredient.  Picaridin at 20%, and DEET at 25% were most effective and worked for 8 hours. Synthetic lemon eucalyptus at 30% was also effective.

Surprisingly, IR3535 did not make the list of recommendations. As expected lower levels of active ingredients, such as 5 percent picaridin or 7 percent DEET were not effective.

What about natural oils? Consumers Report recommends “skipping products made with natural oils” (ref 1). Products with the following ingredients were not effective;  citronella, lemongrass oil, cedar oil,  geraniol, rosemary oil, cinnamon oil, and lemongrass oil. None of the natural products were effective for more than 1 hour.

As reported previously in Mosquito Repellents – Best Options, many of these natural products have not been tested properly for possible health effects.

Mosquito Repellent Choice is Clear

The scientific evidence is clear. Picaridin and DEET are both effective and safe to use in reasonable amounts. No one is suggesting you bath in the stuff.

Do you want to remain organic and take a chance getting Zika? Or use a synthetic product? The answer seems obvious to me.


  1. Mosquito Repellents That Best Protect Against Zika;

  2. Photo Credit: Jim Beckwith
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Robert Pavlis
Editor of
I live in southern Ontario, Canada, zone 5 and have been gardening a long time. Besides writing and speaking about gardening, I own and operate a 6 acre private garden called Aspen Grove Gardens which now has over 3,000 perennials, grasses, shrubs and trees. Yes--I am a plantaholic!

I hope you find Garden Myths an educational site that helps you understand your garden better.

9 Responses to 'Mosquito Repellents That Work Against Zika Virus'

  1. Elizabeth Kiernan says:

    I enjoyed reading bout the citronella plant. Also thought it was a geranium when i first saw it.

  2. Steven says:

    Does burning sage really work?

  3. Martie says:

    Yes, a fan! I lived in Mexico for a short time & always slept with the windows open. A custom was to leave fans on during the night. It wasn’t 100% but it did a fantastic job of keeping the mosquitos away. You’re right, they don’t like the wind.

  4. Jay L. says:

    Is there any tested way to reduce the number of mosquitoes around a deck/patio area?

    I’ve seen talk of citronella but then counter-arguments citing scientific research stating that it does not work. My opinion right now: it’s probably not going to work.

    I’m looking for something that might work outdoors to help minimize the little biters in a small area. I have no delusions that I could get rid of them completely. 🙂

    I have never heard of picaridin before. I will definitely have to research that as a repellent I can apply to myself.

    Thanks in advance,

  5. 1. Zika virus will likely remain a non-issue for the planet. The microcephaly so paraded by the news appears to be geographically restricted meaning there is some environmental factor in association with Zika virus that causes the symptom. One must also be pregnant for this to be an issue.

    2. Mosquito repellent testing should also be done on Culex species which transmit quite a few viruses (including in Canada) as well and Anopheles which transmits malaria. Though so far malaria in the USA is not an issue in the all but the Everglades and southern most Texas and not an issue in Canada, but it is an issue in northern Mexico.

    3. In this situation I applaud the leaving the gene pool philosophy of the organic cult. Adios, adios.

  6. Stephen Jones says:

    Excellent post, thank you very much. I have always used DEET, but will try the picardin this summer. Sounds like it is less greasy than the DEET.