Researchers have made an 'astonishing' discovery that could pave the way for better prevention, detection, and treatment of noma, a fatal and disfiguring childhood disease. A previously unknown species of bacteria has been found in patients with noma, offering new hope for combating the neglected tropical disease.
What is Noma?
Noma, which is fatal in 90% of cases without treatment, begins as a sore on the gums and progresses to destroy the tissues of the mouth and face. It primarily affects young, poor, and malnourished children, earning it the nickname 'the face of poverty.' Survivors are left with lifelong scarring and disfigurement. While data on noma is limited, experts estimate tens of thousands of cases occur each year, mostly in the Sahel region of Africa, though it also appears in other parts of the world.
Although broad-spectrum antibiotics can successfully treat noma, suggesting a bacterial cause, the exact underlying cause has never been established. A study led by the Liverpool School of Tropical Medicine aimed to investigate the bacterial community in the mouths of noma patients, using samples from 19 children in Nigeria.
The Discovery
Modern genetic analysis revealed an apparently disturbed microbial community, with lower levels of normal, healthy bacteria and an increase in other strains. Deeper analysis uncovered a previously undescribed species of Treponema bacteria in most of the noma patient samples. When PhD student Angus O'Ferrall presented the results, senior author Prof Adam Roberts expressed astonishment. The scientists then reanalyzed older samples from other noma patients and found the same Treponema bacteria, currently called Treponema A, present in those as well.
'We don't know causality,' Roberts emphasized. 'We don't know if it can colonise a noma wound because of the architecture and the environment, or if it causes the noma wound.' The team is now conducting a larger study with more noma patients and healthy individuals across multiple countries to answer this question.
Implications for Treatment
Once noma progresses to its necrotising stage, patients face two outcomes: swift treatment with antibiotics, which often leads to recovery but with massive disfigurement and lifelong stigma, or death. Roberts hopes that a test for children with gingivitis that detects Treponema A could prevent these outcomes. 'At the moment, the only thing we have is a clinical diagnosis based on symptoms, like a foul smell or holes in the skin and tissues. But if we know that Treponema A is always or 99% associated with noma at the gingivitis stage, we could detect and treat prophylactically with antibiotics to stop it progressing.'
The current use of broad-spectrum antibiotics for noma treatment risks increasing antimicrobial resistance. A targeted treatment aimed at Treponema A could reduce that threat. Additionally, the drop in healthy bacteria observed in noma patients suggests the possibility of a preventive intervention with probiotics, Roberts added.
Expert Reactions
The study, published in PLOS Neglected Tropical Diseases, involved researchers from the University of Liverpool, Médecins Sans Frontières, and the Noma Children's Hospital in Sokoto, Nigeria. Dr Michael Head, senior research fellow in global health at the University of Southampton, called the findings a useful first step to understanding a 'currently mysterious condition.' He noted that a different version of Treponema causes syphilis, which can also cause mouth wounds and ulcers.
Prof Philippe Guérin, director of the Infectious Diseases Data Observatory at the University of Oxford, agreed the study is 'a valuable starting point and should help stimulate greater interest from both the research community and funders.'
