(36) Geospatial Review of Literature on Noma (Cancrum Oris): Can We Do Better?

Abstract: On December 15, 2023, the World Health Organization declared noma the newest addition to its list of neglected tropical diseases (NTDs) [Button 2023]. Noma, an orofacial gangrene, predominately ravages malnourished children in low-income countries [Srour, Marck and Baratti-Mayer 2017]. The disease reportedly kills up to 90% of those who develop it within as little as two weeks [Farley, Bala et al. 2020]. With noma’s new status as an NTD, the global oral health community is optimistic the disease will benefit from increased visibility and awareness [Olatunji, Kokori et al. 2024]. However, noma has historically experienced extremely poor research into both its etiology and its epidemiology [Farley, Mehta et al. 2021]. The purpose of this study was to evaluate the publications on noma (cancrum oris) from January 1, 2019, to January 31, 2024, for type of publication, quality of evidence, country of origin, and the number of noma cases reported. The analysis was done to look at available publications asking the clinical questions: “From the published articles on noma, what is the quality of that evidence, where are these articles being published, and how many cases are being reported?” A scoping literature review from January 1, 2019, to January 31, 2024, was performed. All available literature was searched via PubMed including “grey literature” via Google Scholar. Potentially relevant publications were identified using the search terms: “cancrum oris,” “noma disease,” “surgical treatment of noma,” and “noma and Africa.” The publications were sorted by type of study and level of evidence, country of origin, and the number of cases of noma they reported. After screening titles and abstracts for relevance, as well as removing duplicate entries, 112 articles were included in the analysis. The most common types of studies available in the literature are case reports (21/112 or 18.6%), literature reviews (21/112 or 18.6%), retrospective reviews (14/112 or 12.5%), and commentary or opinion pieces (14/112 or 12.5%). There were no studies found of level 1 or level 2 evidence. The primary author on articles included in the analysis were primarily from Nigeria (21), South Africa (13), and the United Kingdom (12). The included articles reported a cumulative total of 11,497 cases of cancrum oris. These cases were predominately reported as coming from Nigeria (8,627) and Ethiopia (1,445); several studies also reported pooled cases from multiple locations (1,261).Despite an average of 22 publications per year, the study illustrated an overabundance of case reports and commentary pieces while prospective studies on the disease’s epidemiology, etiology, and risk factors are nearly non-existent. Articles written on noma are frequently done by researchers and surgeons outside of countries where this disease is endemic. Work must be done to strengthen the reporting infrastructure in countries experiencing a high burden of this disease. The cumulative total cases of noma reported in the literature (11,497) do not represent discrete individuals. Instead, in many instances, cases were double-counted during retrospective or surgical reviews published by authors writing multiple articles based on the same or overlapping case databases. Without partnerships to facilitate better case reporting, it is unlikely that we will come much closer to understanding noma’s true epidemiology or geospatial distribution.

Cases of Noma (Cancrum oris) Reported in the Literature (Jan. 2019 - Jan. 2024)
Publications on Noma (Cancrum Oris) by First Author Country Jan. 2019 - Jan. 2024