Some epidemiological observations on noma in Northwest Nigeria

The global incidence of noma is uncertain. Thorough studies to measure this incidence are lacking, though it is well known that noma is prevalent in many countries in the world. Rough estimations for a few African countries have been made in the past by extrapolating data obtained from a few referral centres in these countries. These resulted in a case incidence of noma in Nigeria of 0.8 per 1000, in Niger of 4.0 per 1000 and in Senegal of 2.1-3.6 per 1000.

The noma project in Sokoto has given an excellent opportunity to make a quite reliable calculation of the incidence of noma in northwest Nigeria due to a remarkable linguistic coincidence. From the beginning of the project patients have been called up by broadcasting messages. However there no well-defined word in Haussa for noma, so all patients with a hole in their face were asked to come to the hospital for free treatment of their disfigurement. This resulted in the appearance of two categories of patients: survivors of noma and patients with a cleft lip. Both have been treated without distinction.

Because of the incidence of cleft lip in West Africa is known (0.4 per 1000) and cleft lip does not have per se a significant mortality, and noma a mortality of around 90% comparison of over 600 patient data has made it possible to calculate the incidence of noma in north-west Nigeria: 6.4 per 1000.
Extrapolation of this incidence to the developing countries bordering the Sahara Desert (the noma belt of the world) gives an incidence of 25.600 for that region and a global incidence of 30.000 – 40.000.

This study has been performed by Alexander Fieger, a medical student from Munich, Germany. For more details you may read his publication: Alexander Fieger et al, Tropical Medicine and International Health 2003; 8: 402-407.