The answer to 'flea trails' is that flea trails are the visible tracks left behind by fleas as they move across your floors or furniture. These trails are typically made up of tiny specks of dirt, dried blood, and flea droppings. Common causes of flea trails include a flea infestation in your home, often brought in by pets. Symptoms may include seeing the trails, as well as itchy bites on you or your pets.
The best solution is to address the underlying flea problem. This may involve thoroughly vacuuming and cleaning your home, using flea-killing sprays or powders, and treating your pets with flea medication. If the infestation is severe or difficult to control, it's best to call a professional pest control expert who can properly identify and eliminate the fleas.