Cryptosporidium Water supply contaminant. The elderly and the very young especially susceptible. Fungi Fungi are one of the five kingdoms. Fungal cells, like plants, are not motile. Fungi secrete enzymes to degrade organic matter, such as plant fibers.
Many fungal species are parasitic on plants or animals.
Most fungi which cause infections are opportunistic . Normally causes no problems, but can erupt under some conditions, e.g. antibiotic use, weakening of immune system. Can move into deeper skin layers, produce pus. Not life-threatening, but significant discomfort, stress, and pain.