Spring arrives, heralded by pinkletinks, crocuses … and ticks — followed closely by a flood of pet owners in search of flea and tick control. It’s big business, parasiticides (that means stuff that kills parasites), and the market is inundated with choices. How do you decide which products to use for your menagerie? To decide which options to choose, it helps to learn a little about the lives of fleas and ticks.
Ticks are arthropods, related to mites, scorpions, and spiders. Most species we have here will live on three different hosts during their life cycle. Deer ticks, for example, like mice, then deer, then some third mammal like rodents, dogs, cats, or people. Most species have four developmental stages: egg, larva, nymph, and adult. Larvae and nymphs need a blood meal to molt to the next stage. Ticks will actually gather on vegetation along paths and trails frequented by people and other animals, waiting to be alerted by the warmth, motion, and presence of substances like carbon dioxide in the exhaled breath of their hosts, then hop aboard as they pass. Once on board, ticks attach and start feeding. An adult female can feed for eight to 12 days, engorging to one hundred times her original weight. She mates while still attached to her host, then detaches, and lays anywhere from 100 to 6,000 eggs.
The adult flea is a wingless, six-legged insect that spends the majority of its time living on your cat or dog. It hops but don’t fly. The female flea must bite and take a blood meal before laying her eggs right on Rover. When Rover rolls over, the eggs fall onto his bed, your bed, the carpet, the couch, where they hatch into larvae: nasty, squirmy worms that burrow deep into rugs, between floorboards, anywhere they can wiggle. These larvae live on dander and other organic debris, then spin sticky cocoons, and turn into pupae securely glued to whatever surface they are touching. You can vacuum right over them and not dislodge them. Pupae can remain dormant for extremely long periods of time, waiting for optimum conditions. Like ticks, they recognize the presence of a host by sensing motion, warmth, and carbon dioxide. The pupae then hatch into new adult fleas … who hop onto Rover and start all over again.
Now if you are old, like me, you may think shampoo is what you need. Wrong. Shampoos only kill the parasites currently on Rover, but have no residual effect. As soon as he’s out of the tub, new bugs will happily reinfest him. Old-fashioned powders, sprays, and dips have also been largely replaced by more effective options. For 15 years the market has been dominated by topical products like Frontline and Advantix, to name a few. These are designed so you just pour a small amount of liquid on one or more spots on Rover’s skin along the back once a month. The parasiticide spreads along the oil layer of the skin. Fleas and ticks crawling on the skin are exposed to the product. They don’t need to bite to die. Theoretically, female fleas die before having time to lay eggs, and larvae in the environment die when they consume parasiticide-laden dander that falls off the pet. These topical products, which remain solely on the surface, should not be confused with products like Revolution and Advantage-Multi, which, although applied to the skin in the same way, are actually absorbed into the animal’s bloodstream.
What about flea and tick collars? Aren’t those also outdated? Not any more. Nowadays collars are available that deliver extremely effective parasiticides by continuous release, spreading along the oil layer on the skin in a similar way to the topicals previously discussed. There is only one kind that is safe for use in cats (Seresto, by Bayer), but multiple options exist for dogs. These collars provide six to eight months of protection against both fleas and ticks, and are great for people who have trouble remembering to apply monthly products. The feline collars are breakaway, for safety, so if your cat tends to undress himself, save your money (though Bayer currently will replace one lost cat collar per family for free.) For dogs who swim, frequent immersion in water may shorten the duration, but they still work pretty well. I avoid collars for families with small children, who might be more likely to touch them a lot, exposing themselves to the chemicals.
In recent years we have seen the advent of more types of oral parasiticides, such as Comfortis, Nexgard, and Bravecto. Each product is slightly different. Comfortis, given monthly, kills fleas but not ticks, and is safe for cats and dogs. Nexgard kills fleas and ticks, but can only be used on dogs. Bravecto only needs to be given every three months, and kills fleas and ticks, but can only be used on dogs. All are extremely effective, and eliminate virtually all human exposure to the parasiticides, but you are giving your pet a systemic medication — putting a long-acting medication into his body instead of just on the surface. On the other hand, the chemicals involved specifically target insect physiology, not mammalian, and have minimal reported side effects. To eliminate fleas in your environment, all the household pets need to be on aggressive flea control. For example, if you give the oral pills to Rover but leave Tom untreated, the cat will be a source for continued infestation and poor Rover will keep getting bitten by the fleas breeding on Tom. And if you give Tom the oral pills, he still needs something topical for tick control if he goes outside.
Discuss the particulars of your household with your veterinarian. What delivery methods best meet your needs and your philosophy? Which make you most comfortable? How much do you want to spend? With so many great choices, your veterinarian should be able to help you select an effective flea and tick control protocol tailored to your needs.
