All the factors collectively causing CNE are generally only present in the hinterlands of New Guinea and parts of Africa, Latin America, and Asia. These factors include protein deprivation (causing inadequate synthesis of trypsin protease (an enzyme), to which the toxin is very sensitive), poor food hygiene, episodic meat feasting, staple diets containing trypsin inhibitors (sweet potatoes), and infection by Ascaris parasites which secrete a trypsin inhibitor. In New Guinea (origin of the term “pigbel”), the disease is usually spread through contaminated meat (especially pork) and perhaps by peanuts. (CNE was also diagnosed in post WWII Germany, where it was known as Darmbrand or "fire bowels").
CNE is a necrotizing inflammation of the small bowel (especially the jejunum but also the ileum). Clinical results may vary from mild diarrhea to a life-threatening sequence of severe abdominal pain, vomiting, bloody stool, ulceration of the small intestine with leakage (perforation) into the peritoneal cavity and possible death within a single day due to peritonitis. Many patients exhibit meteorism. Treatment involves suppressing the toxin-producing organisms with antibiotics such as penicillin G or metronidazole. About half of seriously ill patients require surgery for perforation, persistent intestinal obstruction, or failure to respond to the antibiotics. An investigational toxoid vaccine has been used successfully in some developing countries but is not available outside of research.