Greetings!
Short Answer:
Flea bites on dogs and humans look the same. They’ll resemble mosquito bites. However, a primary difference between humans and dogs (or cats) is that allergic animals will vigorously scratch and nip themselves, resulting in secondary infections. This is known as Flea Allergy Dermatitis (FAD).
Read a full description and see pictures on our What do flea bites look like page. Currently, pictures are lacking, but the descriptions are thorough.
Long Answer:
Flea bites initially cause a wheal. This is just a raised area of skin around the bite. Redness and swelling sometimes accompanies the wheal. The initial bite reaction is very similar to mosquito bites.
24 hours later, the wheal is replaced with a papule (a small, hard welt). Again, redness and swelling may accompany it. The papules often occur in groups of three. These lesions are usually very itchy. They fade within a couple days.
Occasionally, some individuals experience more extreme reactions to flea bites. These reactions may take the form of large blisters (bullae).
Scratching a flea bite often leads to a secondary bacterial or fungal infection. These secondary infections fill with pus and resemble pimples.
Allergic dogs and cats experience extremely pruritic (itchy) flea bites. The discomfort induces a lot of grooming and scratching. Secondary infections are common. In these cases, the condition is called Flea Allergy Dermatitis (FAD). Some of the symptoms include pimple-like lesions, broken open skin, fluid excretion, hair loss, foul odor, discoloration of skin, and dandruff and scaly skin.
I apologize that I don’t have any dedicated pages on FAD yet. It’s on my to-do list. I hope this information was helpful!
