What do fleas look like and how do I spot them?

Fleas are more than just a nuisance for your dog. Fleas can cause chronic skin disease and even transmit infectious or parasitic diseases. Some of these can be transmitted to humans too.

Spotting fleas or flea bites on your dog

Spotting fleas or flea bites on your dog isn’t always easy – fleas are small and fast, and some dogs can show signs of severe itchiness and irritation when only a few fleas are present. It’s also important to consider that the adult fleas you see on your dog are only part of the problem. You may be surprised to learn that adult fleas (the ones you see) make up only about 5% of the total population. The remaining 95% (eggs, larvae and pupae) are found in carpets and bedding - in fact anywhere in your house! Adult female fleas can start laying eggs within 24 hours of infesting your dog and can produce up to 50 eggs per day. Eggs can scatter, falling off your dog wherever it goes, spreading the flea infestation throughout your home. Flea larvae then hatch from the eggs, hiding in dark places, deep in carpet, bedding or in cracks in the flooring where they feed on flea dirt and develop into pupae. The flea life cycle is completed when adult fleas emerge from pupae, ready to jump onto a passing host.

What do fleas look like?

It’s important to know what fleas look like to the human eye in order to identify them quickly and accurately. Fleas are small, flat-bodied and dark brown. A fully grown flea is around 3 mm long. It is often easier to spot the flea droppings, or “flea dirt”, that fleas leave behind when feeding.