Catnip Lotion Matches Deet in Mosquito Repellent Trials
Researchers testing an affordable, locally sourced oil in Uganda have confirmed what cats have long known: catnip lotion is as effective as the synthetic chemical Deet in repelling mosquitoes.
Catnip, scientifically known as Nepeta cataria, is a common herb belonging to the mint family. The compound responsible for inducing euphoria in cats, nepetalactone, also possesses insect-repelling properties, although it has not been widely commercialized until now.
Importance of New Mosquito Repellents in Malaria Control
Developing new tools is crucial in combating malaria, a disease transmitted by mosquitoes that affects millions annually and caused approximately 610,000 deaths in 2024. The majority of fatalities occur among young children in African nations. Concerns have been raised about increasing resistance to insecticides and the frontline antimalarial drugs used to treat the disease.
Field Trials Demonstrate Effectiveness of Catnip Lotion
At the Society for Experimental Biology conference held in Florence on Tuesday, a collaborative team from Uganda and Wales presented findings showing that mosquitoes seeking blood meals were less likely to land on individuals wearing catnip-based lotions.
“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,” said Dr Simon Scofield, a senior lecturer at Cardiff University.
“Deet is out of the price bracket for most rural Ugandan subsistence farmers, so buying commercially available mosquito repellents is just not practicable.
“We wanted to make a repellent, which is highly efficacious, but also allows local people to be involved in the production cycle so that it costs a minimal amount of money,” he said.
Dr Scofield also noted that the study did not investigate whether local cats were attracted to lotion wearers.
“We did not conduct any experiments to see if it is attractive to cats, but given that the active ingredient [nepetalactone] has well-known cat-attractive properties, I would expect they would quite like it,”he added.
Laboratory and Field Testing in Uganda
Initial laboratory tests confirmed the potential of catnip oil as an effective insect repellent. Subsequent field trials in eastern Uganda involved monitoring the number of mosquitoes landing on volunteers’ legs during evening hours.
Volunteers were assigned to use different treatments: some applied Deet lotion (the world’s most widely used and effective insect repellent), others used lotions containing 2% or 6% catnip oil, while a control group applied placebo creams.
Local Production and Sustainable Distribution
The research demonstrated that the catnip lotion could be produced locally by a community enterprise. To date, distribution has been free, supported by grant funding. The next phase aims to scale up production and sell the lotion to generate sustainable income for local workers.
“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,” said Scofield.
The Deet lotion used in the trial contained 15% Deet, which is the most commonly available concentration in Uganda. Travelers from the UK visiting malaria-endemic areas are advised to use repellents with higher concentrations.
Expert Commentary and Future Directions
Swai Kyeba, a research entomologist at the Ifakara Health Institute in Tanzania who was not involved in the study, emphasized the need for new vector-control tools.
“New vector-control tools are necessary in the fight against malaria, especially those that are cheap and locally produced, to help improve accessibility.
“However, a challenge with topical repellents is low compliance because they require regular application. This is why they remain a complementary tool in the fight against malaria.”
Kyeba also recommended further research on the use of currently available repellents in Ugandan households before scaling up production of the catnip lotion.
