A reader writes:
On your Web site, you state that cold weather kills fleas (10 days at 37° or 5 at 33°). I live in Ohio and it gets below 10° for weeks at a time. Will below freezing weather, for long periods, kill the eggs too? I don’t heat this house during the winter. I turn off the water and stay elsewhere. If I’m unable to rid it of fleas (using bombs, powders, Revolution, etc.). Will the eggs hatch in the spring and it’ll start all over again? Also, my yard must have fleas because the dogs go crazy out there. Will their eggs hatch in my yard, in the spring, too? How long before a freshly hatched flea can lay its own eggs? I ask because I’m wondering how long to wait before I re-bomb my home, after I kill off all the adult fleas. Is there anything that kills the eggs?
Thanks, I appreciate your time and help.
The reader asks some fascinating questions about fleas. Every insect has a unique life cycle and the flea’s is very interesting.
We have some interesting answers, some of which may surprise you.
Research shows that it’s not only the cold that kills fleas and their egg and nymph stages, but the dry conditions that accompany the low temperatures. Dessication pulls moisture from all three of those stages and, to a lesser extent, the pupal stage. Most of the overwintering fleas are presumably in the pupal stage, which can mature almost to adulthood, then hatch out as adults, ready to feed, as soon as conditions are suitable. In fact, fleas can maintain in the pupal stage for up to three years, then hatch in seconds when they detect motion (vibrations) and/or carbon dioxide from a potential host.
The female flea can lay eggs shortly after her first meal, but she can neither survive nor lay eggs without blood. When flea eggs hatch they feed on the digested blood (feces) the female flea has eaten and passed.
Do not waste your money on bombs. Consumer Reports, one of the most respected institutions in our country, performed a study to determine why bombs were ineffective. They built a simulated living room with simple “furniture” and infested it with a known number of fleas. Following instructions for the size of the room they activated one of the bombs and set it on the “coffee table” they had built for the purpose. Returning in the prescribed number of hours researchers found live fleas directly under the coffee table!
Wanting to know why the product failed, CR’s investigators evaluated the spray pattern. Despite television commercials that claimed the “fog” had great penetrating power to enter furniture and walls, in fact they found the droplets (not fog) went straight up and came straight down. There wasn’t even enough dispersion to kill the fleas directly under the device!
Instead, you want a directional sprayer, such as is available on the Mycodex Environmental Spray (scroll down to IN THE HOUSE). I would recommend that you treat the house as the last thing before you leave it each year, as soon as you return and again three weeks later. Repeat that routine every year for your Ohio situation. Here, in the southeastern US we must treat much more often than that. If your pet’s doctor doesn’t carry Mycodex House Treatment, call around and find a veterinarian who does.
Yard treatment depends on the speed of kill required. In cases where an active, heavy infestation is present, sprays are the best choice. An insecticide spray will kill adult fleas rapidly, but lacks longevity. Long-term treatment is best performed with granules, which you can read about here (scroll down to IN THE YARD).
Flea powders, because they are dry, simply sit where you put them and have difficulty penetrating insects. Therefore, we cannot recommend their use.
Revolution is not only an excellent heartworm preventive, but also contains very effective flea control and flea prevention.
There is but one more step I would recommend. From your veterinarian obtain two tablets of Capstar. Each year, on the day you leave your winter house for the summer one, administer a Capstar tablet. Likewise, on the day you depart for Ohio from the summer home, administer a Capstar. Capstar kills any adult fleas on your pet, begins working in about 20 minutes, and is out of the body in 24 hours. There is no interaction between Capstar and Revolution, so it’s safe to dose both medications on the same day. There would be a clear advantage to Revolution dosing within five days of each departure.
See you tomorrow, Dr. Randolph.