Mosquitos are the world’s deadliest animal. Experts estimate that mosquito-borne diseases like malaria and West Nile virus kill around 1 million people per year.
Bug repellent is one of the best tools available to prevent those deaths, and researchers recently uncovered a new way to keep mosquitoes away: catnip. Scientific studies have shown that this herb — the same one that makes cats lose their minds — is just as effective as DEET. That theory has now been proven, according to a July 7 study from researchers working in Uganda.
The researchers said they proved the efficacy of catnip as a mosquito repellent — and also demonstrated how it could work on a community level in Africa.
How Does It Work?
Catnip, which goes by the scientific name of Nepeta cataria, is a common herb that belongs to the same plant family as mint. Researchers first concluded that use of the plant as an essential oil could be effective against mosquitoes in a 2024 study. Some scientists had test subjects apply the oil directly to their skin, while others added it to a lotion.
The solution works because catnip contains nepetalactone, a volatile chemical compound that naturally repels bugs. It’s the same compound that elicits such a euphoric response in cats.
A group of researchers employed a simple method to test the efficacy of the oil. They started with a Y-tube olfactometer (a long tube with two branches) and put human hands at both ends (one with repellent and one without). Then they inserted mosquitoes into the tube, and tracked which tube the mosquitoes preferred.
Scientists also tested different concentrations of catnip essential oil, diluting it with olive oil. In their results, oil with a concentration of just 2% catnip oil performed just as well against the mosquitoes as standard DEET did. They found that the repellent properties of 2% catnip oil mixed with hand lotion lasted for approximately 4 hours.
Since concentrations of just 2% are effective, the repellent doesn’t require much catnip, and the resulting substance doesn’t produce any strong smells or skin irritation.
Why Does It Matter?
For folks living in sub-Saharan Africa, the area most seriously stricken with malaria, DEET repellent is too expensive to use on a regular basis. A group of scientists (associated with Cardiff University in the U.K.) started a grassroots enterprise to produce the catnip lotion in Uganda. (The full study is available above.)
The plant can be easily grown in mosquito-prone areas of Africa. So instead of having to buy expensive imported synthetic repellants, people can have greater access to an affordable, home-grown alternative.
Other methods of mosquito control, like insecticide-treated nets in homes, are also very effective. But they don’t protect people who work outdoors. For those who spend time outside, some kind of repellent is essential, and catnip presents a far cheaper and more accessible alternative.
And for people in other parts of the world, catnip lotion may be an attractive repellent option as well. Some outdoors folks don’t like DEET because it feels greasy or irritates their skin, and they prefer natural alternatives. DEET can also damage certain plastics and synthetic fabrics that are commonly used to make outdoor gear. Catnip has also proven to be far more effective than other natural options, such as citronella.
