Necrotis fasciitis

Perhaps the most sinister, diabolical, and dreaded organism left alive on Ashrain is the family of microorganisms known as necrotis fasciitis, or 'flesh-eating bacteria'. These species of bacteria and fungus, chillingly, often reside in saturated areas such as the infrequent oases that dot the empty landscape of the ashland wastes. Lurking in these places which are flocked to by terrestrial organisms, and humanity, as the only safe havens in a desert wasteland, these bacterial and fungal species drift in the air as tiny spores, almost invisible to the naked eye. They attach themselves to living organisms by sticking to hair or clothing and can then be carried many hundreds of miles away from their source. Even a single spore, if it alights properly on a target subject, can result in an infection in which the spore feeds on the living tissues of the host organism and multiplies into a rapidly expanding colony. If left unchecked, these colonies can debilitate living organisms and even result in infections that can be fatal.
This is fairly uncommon among human beings who take steps to rid themselves of the parasitic bacteria through cleansing. In rare cases, flesh-eating bacteria allowed to proliferate on a human being with no means of cleansing themselves can lead to gruesome deaths in which the victim comes to resemble a decaying zombie before inveitable death due to blood poisoning. However, muc more commonly, these organisms land on and feed upon carcasses and corpses, reducing the decaying flesh and bones to nothing in a matter of weeks. Because of the prevalence of these species throughout Ashrain, the practice of salvaging recently deceased bodies to be burned for their water is fairly common among survivors. Organizations such as the Carvers take this to a much more serious level, actively hunting and killing survivors and other organisms to salvage their water in blood stills.