My editor at Dogster recently forwarded some promotional materials to me. The materials were from a company that makes dog beds, blankets, car seat protectors, furniture such as cots, and clothing. The products have a twist: They are impregnated with permethrin.
Permethrin is an insecticide. It also is an insect repellant. It is an ingredient in some topical flea and tick preventatives, such as K9 Advantix.
Note the “K9” in the name of the product. K9 Advantix cannot be applied to cats. Cats are very sensitive to permethrin, and the product is toxic (or, to speak with greater precision, more toxic) to them. I have treated countless cats who suffered tremors or seizures after their owners accidentally applied K9 Advantix.
I’ve never been a fan of K9 Advantix. If a product isn’t safe for cats, I don’t want to apply it to my dog, either. In fact, permethrin is toxic to dogs as well. However, they are less sensitive to the product, so they usually escape unharmed when a small quantity of permethrin is applied to their skin. Nonetheless, I have seen what happens when a Lab-sized dose of permethrin is applied to a Chihuahua, and it’s a risk I don’t wish to take.
The promotional materials for the products in question are quick to point out the risks of topically applied permethrin. The company emphasizes, correctly, that permethrin-impregnated clothing and furniture pose much less risk.
The company that produces the products bills them like this:
[T]he extensive assortment provides a total solution for pet owners to fend off bugs everywhere – at home, outdoors, in the car, or when traveling . . . [the line of products] protects against a variety of insects including mosquitoes that can carry dangerous diseases such as Zika virus, malaria, and more.
The choice of words is telling. The products protect against bugs at home and in the cars. They protect against Zika virus and malaria. This leaves me wondering: Are these products a solution in search of a problem?
Let’s start with Zika and malaria. Zika virus certainly has been in the news lately. It can cause severe problems, including a horrifying condition called microcephaly, in fetuses carried by infected women. It appears to pose a similar risk to pregnant pet chimpanzees. But to date there is no evidence that Zika virus can infect, let alone sicken, dogs. Malaria is estimated to kill more than a million people, mostly children in sub-Saharan Africa, each year. It can infect birds. But the type of malaria people contract does not affect dogs, and it has been eradicated from the United States and Europe. (A disease that colloquially is called “canine malaria” also exists, but it is a misnomer — it refers either to leptospirosis or babesiosis, which are not spread by mosquitoes.)
And how about the word “bugs”? Just how dangerous are bugs to dogs?
In fact, there are three “bugs” that pose significant risks to dogs. Mosquitoes are a risk to dogs because they spread heartworm disease. Ticks are a threat because they can spread maladies including Lyme disease, ehrlichiosis, Q fever, and, yes, babesiosis to dogs. They also can cause a paralytic syndrome in dogs who are heavily infested. Fleas are the most ubiquitous menace. They cause all manner of skin problems, spread disease, and in large numbers can cause anemia through blood loss.
How beneficial would the products be against these awful arthropods? The wearable vests produced by the company certainly might be beneficial to hunting dogs or dogs who live in areas where ticks are extremely common. But they don’t cover the entire body, and they don’t protect dogs where they are most vulnerable to mosquito bites: their snouts. Permethrin-impregnated beds and car covers may be of some benefit in areas with lots of mosquitoes and high rates of heartworm.
But when I read the promotional materials, I do not notice a focus on such uses for the products. Instead, the materials seem to play on human bug phobia. Humans generally hate and fear bugs. I have learned over the years that such fears are rather silly.
My first adventure in a rainforest took place in Corcovado National Park in Costa Rica. I had to cut the trip short for my vet school interview. On the flight home, I experienced an unpleasant sensation: My backside was very itchy. In the plane’s restroom, I made a discovery: Dozens of ticks had attached themselves to my most personal areas. I feared I might die from some crazy tropical disease. I was horrified, but in time I learned that my concerns were unfounded. The result of my tick infestation was precisely nothing other than itching. I suffered no long-term consequences whatsoever.
A couple of decades later I traveled to the buggiest place on earth: the Amazon rainforest in Peru. Newly arrived tourists would show up at the jungle lodge decked out in ridiculous head-to-toe outfits impregnated with permethrin. Locals and long-time residents such as the owner of the lodge, however, dressed differently. They wore shorts, and the men often went shirtless. Bugs and spiders swarmed them, but they were indifferent. I found out that malaria was nonexistent in the region, and experienced people thought that it made sense simply to ignore the bugs.
Permethrin-impregnated dog beds and vests will not protect dogs’ owners from creepy crawlies because, with the exception of fleas, dogs generally don’t carry bugs around. They don’t spread bedbugs. They don’t walk around with spiders and beetles crawling all over their fur. Mosquitoes don’t use them as gathering places, and ticks that fall off of them must go through a transition of life cycle stages before they’re ready to feed again.
I recommend good flea and tick preventatives for the sake of the dogs who receive them. But there is no reason to fear that your dog is a reservoir for scary bugs, and there generally isn’t a reason to be scared of bugs in the first place.
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