Fleas are tiny insects, measuring only 1.5 to 3.3 mm in length. They have six legs, two antennae, and three body segments, but these features are difficult to see without magnification. Their flat, narrow bodies allow them to move easily through fur or hair, and their legs are equipped with spines that help them grip as they crawl.
If you spot a flea on your pet, it will appear as a thin, brown bug that quickly disappears into the fur. Off your pets, fleas are recognizable by their ability to jump impressive distances. To put it in perspective: if a flea were the size of a human, it could leap over an entire house in a single bound.
Fleas feed on blood. The most common species found in homes is the cat flea (Ctenocephalides felis), which prefers cats and dogs but will also bite humans when necessary.
Fleas are more than just itchy pests—they’re associated with several health problems affecting both people and pets, including:
Learning the symptoms of these conditions can help protect you, your family, and your pets.
When fleas bite, they inject saliva into the skin. The immune system reacts to this saliva by releasing histamine, which causes itching. Scratching the bites often makes the irritation worse and can lead to further discomfort or infection.
Yes, but not for long. Fleas need animal hosts to survive, and humans don’t make great substitutes. Regular showering and shampooing make it nearly impossible for fleas to live on people for any length of time.
A flea infestation can take hold in as little as two weeks. Here’s how their life cycle works:
Even if you don’t see adult fleas, eggs and larvae may already be present in your home, making infestations harder to detect.
Fleas usually come from your yard. They emerge from cocoons, jump onto your pet, and hitch a ride indoors. Once inside, they live on your pets or hide in carpets, rugs, and furniture, making them difficult to eliminate.
On pets, fleas cause constant scratching. If you notice your pet itching, use a flea comb to check for small black specks (flea dirt) or live fleas. Don’t wait for scratching to start, routine checks after outdoor activities are a smart habit.
Indoors, fleas often hide in rugs, furniture, and other soft surfaces. You may notice them jumping when you walk by or discover itchy bites on your legs and ankles.
They can be, but success often depends on proper application. Many DIY efforts fail because people overlook certain life stages of the flea or miss critical treatment areas. Professional treatments tend to be more effective, as trained technicians know how to target all stages—eggs, larvae, pupae, and adults.
If you're worried about a flea problem in your home, contact Harbor Pest Control to schedule a free inspection. Our local pest control experts understand flea behavior, know where to look, and how to eliminate infestations effectively.
Fleas often enter yards via wildlife such as raccoons, squirrels, and stray animals. To prevent infestations, start with your outdoor space:
Also, protect your pets. Talk to your veterinarian about effective flea prevention products.
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