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Global Warming Fantastic for Fleas


You can win the battle, and you can win the war. Experts talk about how to bust fleas.

    Global warming must be happening. Just ask the fleas. “It’s not that the best of the flea products (to deter and kill fleas) don’t work consistently, it’s that due to climatic shifts there may actually be more of a flea problem,” says Dr. Michael Dryden, veterinary parisitologist at Kansas State University College of Veterinary Medicine – Manhattan.  “Much of the country is experiencing warmer winters and wet springs. I have no doubt that the fleas are benefiting.”

      Fleas hate the extreme cold and dry weather. Mild winters and soggy springs are ripe for a festival for fleas.

      Sharing Dryden’s views is veterinary dermatologist Dr. Linda Frank, professor of dermatology at the University of Tennessee College Of Veterinary Medicine – Knoxville. 

“At one time, you didn’t really require year-round flea control here (in Tennessee), but I believe you do now.

      Before PROGRAM (which prevents fleas from reproducing) hit the market in 1995, the best selling flea fighters were made with pyrethrins or pyrethoids.  However, increasingly fleas in many parts of America were building resistance and were unaffected by the products. Some pet owners feel that process of flea immune systems adjusting to man-made weaponry is happening again.

      “It’s fair to say that there may be some resistance problems gradually occurring,” according to veterinary dermatologist Dr. Gail Kunkle, professor of veterinary dermatology in the Department of Small Animal Medicine Clinical Sciences at the University of Florida College of Veterinary Medicine – Gainesville, FL. “I know some colleagues who are also concerned.”

      However, Dryden is not among them. He’s researched the issue and finds no signs of product failure. “That’s not to say there aren’t isolated instances of resistance out there somewhere, but if they are, they are limited.”

      Dryden has no doubts, however, that some homes are infested with fleas, despite using products which he calls “very safe and very effective.”

      He says the biggest failure in flea control is human complacency. “People assume they only need to use a product for six or seven months but because of the warm winters and wet springs, now they really need to use it for ten months or an entire year. While that may not be the case in North Dakota, it is in places like Kansas or parts of Illinois, for example. Or in an effort to save money – people don’t see any fleas – they think things are going fine, so they skip a month or two (of administering the monthly product). Especially in places, like Florida, it’s as if the fleas have a battle plan – and they’re ready to take advantage of complacency.”

      Frank adds, “The manufacturers of the spot-on products (delivered in a tube squeezed between the shoulder blades of a pet) maintain they can hold up to water. But I wonder about pets who swim all the time and are constantly in water, or who are bathed frequently with shampoos.”

      Flea prevention is a veterinary issue, according to Kunkle. “Talk to your veterinarian about your pet’s lifestyle – and then determine a strategy, which product or combination of products are the best choices.”

      Kunkle says even if the fleas can beat one product (which is debatable), they can’t possibly defeat two. She suggests using an adulticide (which will zonk adult fleas) such as Advantage, Frontline Plus or Revolution in combination with an insect growth regulator (which prevents eggs from hatching) such as Sentinel or PROGRAM.

      Arguably Frontline Plus may be used alone since it gives a terminal blast to adult fleas, but also breaks the flea life cycle by killing their eggs and larvae preventing re-infestation.

      Dryden offers another option, which is to use Sentinel or PROGRAM (which prevents the reproductive cycle but doesn’t kill adults) with a daily quick killer of live fleas, called CAPSTAR, as needed.

      This plan of combining products, which was developed by Dryden, is called an integrative approach. In Dryden’s perfect world, everyone would use an integrative approach. If enough people did – it’s one offensive tactic that really could impact the future of the species of flea that most affects our pets (Ctenocephalides felis). “Not only would you kill adults, but you’d limit their reproduction,” he explains.

      Fleas spread diseases like tapeworms, and might create considerable allergic responses in some pets. After all, the flea was responsible for spreading the Great Plague in Europe. No one wants fleas. And when an infestation occurs, those buggers don’t hesitate to bite people. No wonder, everyone seems on board with the idea of annihilating them. Still, out of concern for our pets – a safe stealth attack is best.  That’s why Sentry created a new series of natural flea (and tick) busting products for dogs and cats called Natural Defense. The ingredient list in Natural Defense sounds like a human snack list, and includes peppermint, cinnamon, thyme and lemon grass oils.

      Dryden, who was unfamiliar with the new Natural Defense line couldn’t offer a specific comment. He does add, “It’s important to understand, just because something is natural doesn’t mean it is not a chemical – lots of chemicals are natural. And their safety is unknown. In fact, it’s amazing how safe the current (veterinary recommended) flea products are.”

      Dryden noted pier-review studies have proven the safety as well as the efficacy of those established veterinary flea products currently on the market. And no such studies have been published for Natural Defense (available over the counter wherever pet supplies are sold). Although, he does concede, there is a market of consumers who will likely be impressed with using these presumably safe and familiar sounding ingredients.

      Joel Adamson, vice president marketing for Sergeant’s Pet Care Products, Inc., the manufacturer of Natural Defense, is quick to point out it’s not as if no research has been conducted on Natural Defense. Although, he actually agrees that if it’s natural, it doesn’t necessarily follow that it’s better or safer. He says, “In this case, we’ve come out with something that works that we believe people will like.”

      Dryden cheers, “The good news is that there are choices, and if you use the products like you’re supposed to – you should never see fleas again!”

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Steve Dale is a certified animal behavior specialist who has been a trusted voice in the world of pet health for over 20 years. You have likely heard him on the radio, read him in print and online, and seen him speaking at events all over the world. His contributions to advancing pet wellness have earned him many an award and recognition around the globe.

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