Flea bites are small, red, itchy welts that occur when fleas, tiny parasitic insects, feed on the blood of humans or animals. These bites often appear in clusters or lines and are most commonly found on the lower legs and ankles. Fleas are typically found in areas where pets reside, as they thrive in warm, humid environments. The bites can cause discomfort and may lead to scratching, which can result in secondary infections. While flea bites are generally harmless, they can cause allergic reactions in some individuals. Treatment usually involves cleaning the area and using anti-itch creams or antihistamines to relieve symptoms.