Noma: a neglected scourge of children in sub-Saharan Africa.

Poverty is the single most important risk indicator for noma (cancrum oris), a severe gangrene of the soft and hard tissues of the mouth, face, and neighbouring areas. The risk factors associated with an increased probability of noma developing include the following: malnutrition, poor oral hygiene, and a state of debilitation resulting from human immunodeficiency virus (HIV) infection, measles, and other childhood diseases prevalent in the tropics. There are many similarities between noma and necrobacillosis of the body surface of wallabies (Macropus reforgriseus), and it is proposed that noma results from oral contamination by a heavy load of Bacteroidaceae (particularly Fusobacterium necrophorum) and a consortium of other microorganisms. These opportunistic pathogens invade oral tissues whose defences are weakened by malnutrition, acute necrotizing gingivitis, debilitating conditions, trauma, and other oral mucosal ulcers. The current escalation in the incidence of noma in Africa can be attributed to the worsening economic crisis in the region, which has adversely affected the health and well-being of children through deteriorating sanitation, declining nutritional status and the associated immunosuppression, and increased exposure to infectious diseases. Prevention of noma in Africa will require measures that address these problems, and most importantly, eliminate faecal contamination of foods and water supplies.