A study presented at the Society for Experimental Biology conference in Florence on Tuesday found that a 6% catnip oil lotion is just as effective as Deet at repelling mosquitoes. Researchers from Cardiff University and partners in Uganda developed the low-cost, plant-based repellent to combat malaria in rural areas.
How Catnip Oil Performs Against DEET
The research, conducted by a team working between Wales and Uganda, focused on the insect-repelling properties of nepetalactone, the chemical in the catnip plant (Nepeta cataria) that triggers euphoria in cats. Laboratory tests and field trials in eastern Uganda demonstrated that a 6% concentration of catnip oil matched the efficacy of Deet. A 2% concentration was found to be only marginally less effective.
To verify these findings, researchers monitored how many mosquitoes landed on volunteers’ legs during the evening. The study compared the catnip lotions against placebo creams and a 15% Deet lotion, which is the most widely available version in Uganda.
“We found that a 6% catnip oil was just as effective as Deet, and the 2% catnip oil was only marginally less effective than that.”Dr Simon Scofield, senior lecturer at Cardiff University
While the lotion shows promise, the fight against malaria remains complex. Malaria infected approximately 282 million people annually and killed 610,000 in 2024, primarily young children in Africa. Health officials are increasingly concerned about rising resistance to both insecticides and frontline drugs.
Economic Stakes and Local Production in Uganda
The drive for a botanical alternative is rooted in economics. Dr. Scofield noted that commercially available repellents like Deet are often priced beyond the reach of rural Ugandan subsistence farmers. The goal of the project is to integrate local communities into the production cycle to keep costs minimal.
Currently, the lotion has been distributed for free via grant funding. However, the project is transitioning toward a commercial model to ensure long-term viability.
“Once we know that we can sell and distribute the repellent at a low cost, that should generate a self-sustaining system where the money is flowing back to everybody at each stage in the development,”Dr Simon Scofield, senior lecturer at Cardiff University
Swai Kyeba, a research entomologist from the Ifakara Health Institute in Tanzania, agreed that cheap, locally produced tools are necessary to improve accessibility. However, Kyeba warned that topical repellents face a “low compliance” hurdle because they require frequent reapplication.
Comparing Other Natural Alternatives
Catnip is not the only botanical oil under scrutiny.
| Repellent Type | Reported Efficacy | Duration/Notes |
|---|---|---|
| Patchouli Oil | Equivalent to DEET | 3 hours (Aedes aegypti) |
A study published in ACS Omega found that patchouli oil can protect against Aedes aegypti mosquitoes for three hours when combined with an unscented cream to prevent the oil from breaking down in the air.
The ‘Gold Standard’ Under Pressure
For decades, Deet (N,N-Diethyl-meta-toluamide) has been the primary recommendation for travelers and residents in malaria-endemic regions.
Practical Limitations and Safety
Despite the efficacy of catnip and patchouli, users should be aware of specific side effects. Dr. Scofield admitted that since nepetalactone is a known cat attractant, the lotion would likely attract local cats, though this was not a primary focus of the research.
Beyond botanical oils, other common yard treatments are often less effective than advertised. Lawn insecticides only kill mosquitoes present at the time of spraying, and because mosquitoes can fly one to three miles, yards repopulate quickly. Furthermore, these chemical sprays can harm pollinators like bees and butterflies.
Note: This article is for informational purposes and does not constitute medical advice. Please consult your healthcare provider before starting any new topical treatment.
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