Pulicosis (also known as "flea bites") is a skin condition caused by several species of fleas, including the cat flea (Ctenocephalides felis). As well as the dog flea (Ctenocephalides canis). This condition manifests itself after as few as one flea bite. The bite(s) may not even be noticed. Within minutes of being bitten, skin irritation begins. This can range from extremely mild irritation, to severe irritation. After 48-72 hours, a more severe rash like irritation may begin to spread across the body. Symptoms include swelling of the bitten area, erythema, ulcers of the mouth and throat, restlessness, and soreness of the areolas. If these symptoms appear, seek immediate medical attention. In extreme cases, within 1 week after being bitten, the condition may spread through the lymph nodes and begin affecting the central nervous system. Permanent nerve damage can occur.:450
If there are excessive bites, pets can also develop flea bite dermatitis which can potentially be fatal if no actions are taken. However, dogs and cats are not the only ones that are at risk. Humans can suffer from flea bites  and depending on a variety of factors, it can cause much pain and discomfort. While there are a number of treatments available, it's very important to resist the urge to scratch the bites as this can make it worse, sometimes even causing a serious infection. Various over the counter medications including anti-scratch cream can be very effective.