Buruli ulcer: Africa’s neglected but third most common mycobacterial disease

Th buruli ulcer is considered to be a neglected tropical disease but is the third most common bacterial infection after tuberculosis and leprosy. Buruli ulcer is a skin infection that kills the cells and tissue in an affected area and creates ulcers on the skin. It is caused by a bacteria and is the third most common bacterial disease after TB and leprosy.

The disease was first reported in the 19th century by British physician Sir Albert Cook. But it was only in 1998 that the World Health Organization started to pay attention, addressing it as a neglected tropical disease.

But more than 150 years after buruli ulcer was discovered, scientists still haven’t figured out how the mycobacterium that causes the disease is transmitted. There is still no cure or vaccine. The only way to control it is to detect the infection early and treat it with antibiotics.

The disease also has social consequences. Buruli manifests as large skin ulcers. These are unsightly and people who develop them are often stigmatized. In areas where the disease is endemic on the continent there is also a belief that it is caused by “witchcraft” or “allogens” (immigrants).

A disease of the tropics
Buruli ulcer is largely endemic in the tropics and has been reported in more than 30 countries in Africa, South America and Asia, as well as in Australia. In Africa, the worst-hit countries are concentrated in the west and center. These include Cote’ d’Ivoire, Ghana, Benin and Cameroon.

Of the 33 globally affected countries, 15 are found in Africa. Between 1978 and 1999, up to 22% of people living in communities where the disease was endemic were affected. In this period Côte d’Ivoire reported 15 000 new cases. But at the last World Health Organization buruli ulcer meeting, there was a significant decline in most endemic countries.

The disease is most prevalent in impoverished rural communities. Children under the age of 15 are the worst affected but there is no gender specificity. It often starts as an itchy nodule or papule on the skin. This develops into a massive skin ulcer if left untreated.

                        A Ghanaian boy with a buruli ulcer on his arm. (Supplied)

 

              Swab-sticks need to be tested for buruli ulcer to be diagnosed. 

Doctors still rely on century old microscope and laboratory techniques for diagnosis. Swabs or tissue are taken from the cut, fixed on slides and stained to identify the bacteria. Modern techniques used to diagnose the disease involve amplifying genes to detect the bacteria.

Until 2006 buruli ulcers were treated by cutting them out surgically. But in the past ten years antibiotic chemotherapy using anti-TB drugs has been used with remarkable success in early lesions and also in conjunction with wound healing post-surgery.

Scientists and researchers are still developing urgently needed new anti-mycobacteria drugs. They are investigating the viability of various resources, including fungal and plant-derived biologically active compounds that may stop the bacteria from growing during infection. But their efforts are hampered by the slow-growing rate of the bacteria.

Filling the gaps
Given that there is a great deal that’s not known about the disease, research is targeting vaccine development, how the disease emerges and is transmitted, early detection and diagnosis, and effective control strategies. These are the priority research areas directed by the World Health Organization.

In addition, health education campaigns are being directed towards raising the public’s awareness about the disease and that medical treatment is preferable to traditional remedies. The World Health Organization has produced cartoons to help children understand and accept the disease. The campaigns will go a long way to de-stigmastize the disease, which is still marked by the stamp of shame.

Esenam Dzifa Buatsi, a biochemist and molecular biologist at the University of Ghana was integral in the writing of this article.

The Conversation


Lydia Mosi, Lecturer at the Department of Biochemistry, Cell and Molecular Biology, University of Ghana

M&G

 

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