You may not know you have been bit until hours later. There will likely be more than one spot in a single area – usually 4-5. It’ll be itchy. The bite site may look like a red sore or bump. The spots may even bleed. Fleas usually go for the ankles, waist, behind the knees, the bend of the elbows and armpits. The rash may even turn white. Don’t scratch it because you may cause an infection.