A mother determined to shield her children from tick-related disease helped inspire the development of a gentler repellent made without the harsher chemicals found in many common pest-control products.
Most conventional tick repellents rely on ingredients such as DEET, which forms an invisible vapor shield over skin and clothing, making it harder for ticks to sense body heat and attach themselves.
Although these formulas are widely regarded as effective, they can be tough on the skin. Some users report irritation, redness and blistering, while rare cases have been linked to seizures, confusion and other neurological symptoms.
Researchers in Canada have now created a spray that uses compounds derived from essential oils as an alternative approach.
Dr Nicolette Faraone, a biochemist at Acadia University in Nova Scotia, said she had seen tick numbers rise sharply across the province’s rural communities in recent years, describing the increase as “exponential.” The trend mirrors conditions in the US, where officials believe the country is facing its worst tick bite season in more than 10 years.
Faraone began the project in 2016 after connecting with Lisa Learning, a mother whose two sons had both been diagnosed with Lyme disease earlier that year.
Lyme disease, which affects nearly 500,000 people in the US and 7,000 in Canada each year, is a bacterial infection spread by blacklegged ticks, commonly called deer ticks.
The illness can trigger flu-like symptoms and a gradually widening “bullseye” rash. In uncommon but serious cases, it can disrupt electrical signaling in the heart and lead to fatal cardiac arrest, while some patients experience lasting problems such as severe fatigue, brain fog and sleep disturbances.
Lisa Learning is pictured with her two sons. She was inspired to start Pureguard after both boys contracted Lyme disease
Pureguard spray has been shown to protect against blacklegged ticks (pictured above), which transmit Lyme disease
While a heavy course of antibiotics helped both boys – Lucas and Darian Wallet – return to normal, Learning was determined to make sure they were never sickened by ticks again.
‘I started to look for my own solution,’ Learning told CTV News.
She began researching alternatives to standard tick sprays with chemicals like DEET, instead focusing on essential oils as a base.
Teaming up with Faraone, who is an expert on the effects of lemongrass oil in tick prevention, Learning developed a non-toxic botanical spray called Pureguard.
The spray, which is sold online and at retail stores in Canada, uses the active ingredient Citriodiol, which is derived from oil of the Eucalyptus citriodora tree, also known as lemon-scented gum.
The CDC estimates Citriodiol concentrations above 30 percent can provide complete mosquito protection for six to 10 hours.
It has also been linked to about five hours of protection against deer ticks and lone star ticks, which transmit the life-threatening allergy Alpha-gal syndrome.
For comparison, DEET-based repellents typically contain concentrations ranging from four percent to 100 percent and protect for roughly the same amount of time.
Much like DEET, Citriodiol is thought to interfere with ticks’ sensory receptors, which masks a human’s presence, preventing ticks from landing on the surface of the skin.
Research from Faraone and her colleagues at Acadia University published earlier this year tested oil from lemon Eucalyptus on humans and lab models over the course of six hours.
Dr Nicolette Faraone, a biochemist at Acadia University in Nova Scotia, is pictured above. She works with Learning on Pureguard’s products
They found the oil repelled blacklegged and American dog ticks significantly more than the control solution, and the oil had the same effectiveness as a solution containing DEET. Blacklegged ticks transmit Lyme disease and babesiosis, while American dog ticks can carry Rocky Mountain Spotted Fever.
The new all-natural tick repellent that protects you against devastating diseases without dangerous chemicals
Additional research has found Citriodiol significantly reduced the attachment of castor bean ticks on humans.
Pureguard (pictured above) is sold online and at retail stores in Canada
These ticks, which are native to Europe and North Africa, transmit Lyme disease and tick-borne encephalitis, a viral illness that can lead to life-threatening meningitis and brain swelling.
Citriodiol also has low transdermal absorption, meaning most of it does not get absorbed into the bloodstream, reducing the risk of irritation and rare but serious side effects such as headache, high blood pressure, nausea and vomiting.
‘We are shedding light on understanding how ticks work,’ Faraone told CTV News.
Learning said she hopes the spray will continue to protect Canadians and people in other countries, such as the US, from tick-borne illness.
‘In the beginning, it was just to protect my kids,’ she said.
