Fungal infections, Artwork. Colonies of fungi on a petri dish with examples of fungal skin infections. In the background are fungal hyphae (filaments). Many fungi live on our body without causing any problems. However, a weak immune system or course of antibiotics can lead to the fungi proliferating and infecting the skin. One of the most common fungal skin infections is ringworm (tinea), which can be caused by three types of fungi, Trichophyton sp., Microsporum sp., and Epidermophyton sp.. Other fungi that can infect the skin include Candida albicans, which causes thrush, and Malassezia sp., which cause scaly flaky rashes. Treatment is with antifungal drugs.