Fleas thriving this year in the Delaware Valley

    Having problems with fleas on your pets even though they are on medication designed to keep the pests away? You’re not alone.


    Ryan Clay of West Philadelphia noticed fleas on his two small dogs for the first time this fall, and he started to ask around to see if he was the only one.

    “After talking to other pet owners, other friends, we realized this problem wasn’t limited to just our pets, which saved us a lot of embarrassment, frankly,” Clay said. “All across Philadelphia, we were finding out other friends were having the same problem.”

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    Daniel Morris, a veterinary dermatologist at the University of Pennsylvania, said the flea problem seems especially bad in our region this year. It’s likely because of the weather.

    “When the relative humidity gets to 70 percent or greater, the survival of flea eggs and their ability to hatch increases fourfold,” Morris said. “So the wetter the summer we have, the better they do.”

    Flea eggs thrive in humid conditions, and adult fleas survive better when temperatures don’t top 95 degrees for too long in the summer.

    Morris recommends treating all pets with preventive flea and tick medication, and sticking closely to the regimen recommended on the box. He said pet owners who apply the medications incorrectly are probably less likely to get away without an infestation this year, when there is a bumper crop of fleas.

    Bugs that are outdoors tend to die off after sustained periods of freezing temperatures, but Morris generally treats his own pets with medication all year.

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