The symptoms of a skin infection also vary depending on the type. Common symptoms include redness of the skin and a rash. You may also experience other symptoms, such as itching, pain, and tenderness.See a doctor if you have pus-filled blisters or a skin infection that doesn’t improve or gets progressively worse. Skin infections can spread beyond the skin and into the bloodstream. When this happens it can become life-threatening. This occurs when bacteria enter the body through a break in the skin, such as a cut or a scratch. Getting a cut or scratch doesn’t necessarily mean you’ll develop a skin infection, but it does increase your risk if you have a weakened immune system.A decreased immune system can be the result of an illness or the side effect of medication.Viral skin infection: The most common viruses come from one of three groups of viruses: poxvirus, human papillomavirus, and herpes virus.Fungal infection: Body chemistry and lifestyle can increase the risk of a fungal infection. For example, you may experience multiple bouts of athlete’s foot if you’re a runner or if you sweat a lot. Fungi often grow in warm, moist environments. Wearing sweaty or wet clothes is a risk factor for skin infections. A break or cut in the skin may allow bacteria to get into the deeper layers of the skin.