As we move into summertime and look forward to outdoor activities such as biking, hiking and camping, people start to worry about Lyme disease. While this infection can be serious, it is not the only disease that ticks can transmit. Rocky Mountain spotted fever, anaplasmosis and babesiosis are also serious concerns. In addition, a bite from a lone star tick can trigger a potentially deadly delayed reaction to eating red meat. Doctors refer to this as an “alpha-gal allergy.” What are the best tactics to prevent tick bites?
How Can You Prevent Tick Bites?
Q. What’s the most effective bug spray to keep ticks off? We walk our dogs in the woods almost every day and would like to avoid tick-borne diseases.
A. It is safest to avoid tall grass and underbrush if you can. Of course, that may not be practical when you are walking dogs. According to Consumer Reports (July, 2019), either putting DEET bug repellent on your skin or wearing permethrin-treated clothing can help. DEET also works well to repel mosquitoes.
A few years ago, a team of researchers at New Mexico State University tested a range of products promoted for preventing mosquito bites (Rodriguez et al, Journal of Insect Science, online, Feb. 16, 2017). Only DEET, a tried-and-true insect repellent, and oil of lemon eucalyptus were very effective at discouraging Aedes aegypti mosquitoes. This is important because this type of mosquito carries viruses that cause Zika, yellow fever, chikungunya and dengue.
What Didn’t Work for Mosquitoes:
Wearable devices such as bracelets were almost totally ineffective. People should not rely on them. Citronella candles, a popular product for people who don’t like bug spray, did not work well either.
The scientists urge consumers to read the labels on their spray and choose one with lemon eucalyptus oil or DEET. When there is a possibility that a mosquito bite could lead to a serious infection, only the most effective repellent will do.
Unfortunately, oil of lemon eucalyptus, while effective against mosquitoes, is less effective against ticks. Picaridin is a non-DEET insect repellent that does appear to work quite well against ticks. Unlike DEET, picaridin will not dissolve plastics or synthetic fabrics.
Wear Permethrin-Coated Clothing:
Long pants are an important barrier to prevent tick bites. You will get the best protection by tucking the cuffs of your pants into your socks. To stay even safer, you may want to consider gaiters impregnated with permethrin. Two brands to consider are Lymeez Tick Gear and Outdoor Research Tick Gaiters.
Andrea in NC offered this advice:
“I highly recommend wearing Insect-Shield gear. You can buy shirts, socks, pants, hats and buffs at REI or other outdoor stores. Permethrin is bonded to the clothing, which can be washed up to 70 times before the effect disappears (don’t dry clean, though!). We live in NC and recommend it to all our friends. It really works. Also, you can ship your own clothing to their factory in Greensboro and they will do the same treatment (much cheaper option!). I first bought this before a trip to Cambodia. I wear it every day during the summers here!”
KAF in Massachusetts has an additional caution for cat lovers:
“I work outdoors and use permethrin-treated clothing all the time. The number of ticks I find on me has dropped. It is important to know that while people and dogs seem to handle exposure to this chemical with no ill effects, cat do not. I do not know about other animals but it may not be safe for aquatic life if you fish or wade in the water. At home, I keep clothing I am not wearing in a sealed plastic box or in my car away from my cats. I also change out of when i get home and wash this clothing only with other permethrin clothing and not my everyday other clothes. It has not been approved for use in Europe.”
Tick Check Every Day:
Even with such precautions, however, you must perform tick checks whenever you come inside from your walks. Take off your clothes, put them in the wash and check your skin all over. Remember that ticks like to hide in cracks and crevices. The sooner you find and remove any ticks that have attached themselves to you, the better.
How Quickly Does a Tick Transmit Disease?
It takes about 24 hours or possibly a bit longer for a tick to transmit Borrelia burgdorferi, the pathogen that causes Lyme disease. However, other diseases such as Rocky Mountain spotted fever are transmitted much more quickly.
Several years ago, Brazilian scientists found that ticks may be quicker to pass along their germs than anyone imagined (Emerging Infectious Diseases, Sep. 2014). In an experiment, they exposed guinea pigs to infected ticks and found that the rickettsia of Rocky Mountain Spotted Fever appeared in the animals within just 10 minutes of the tick attaching.
The dog ticks that are generally responsible for this disease in the US have not been studied in a similar experiment, but it would be foolish to assume that it takes a long time for the germs to pass from tick to human. There is currently no evidence suggesting that the Borrelia of Lyme disease are transmitted more quickly than 24 hours, however (Ticks and Tick-Borne Diseases, March 2018). Efforts to prevent tick bites and remove ticks promptly remain the best way to protect yourself from disease.