Tissue infections occur when harmful microorganisms, such as bacteria, viruses, or fungi, invade and multiply in body tissues. These infections can affect various parts of the body, including the skin, muscles, and organs. Common examples include cellulitis, which affects the skin, and abscesses, which are localized collections of pus. Symptoms of tissue infections often include redness, swelling, pain, and warmth in the affected area. In some cases, fever and fatigue may also occur. Treatment typically involves antibiotics for bacterial infections or antifungal medications for fungal infections, depending on the specific pathogen involved.