Jonathan Osorio and Dr. Steven W Graves, Chemistry and Biochemistry

During this past summer, I had the wonderful opportunity to travel to southern Ghana with the Humanitarian Aid Relief Team to study the effects of Buruli ulcer in rural endemic villages. From May 12 to June 21, I was part of a small research group studying the effects of Buruli ulcer on villagers in the Ga District. Part of my research included investigating their cultural beliefs that related in any way to possible contraction of the disease.

Commonly known as Buruli ulcer, Mycobacterium ulcerans was first documented as a case study in 1948. It was not until 1997, after much obscurity, that Buruli ulcer was recognized by the World Health Organization as a major public health problem. Buruli ulcer is the third most common form of mycobacterial infections in humans, after tuberculosis and leprosy. Of the three, Buruli ulcer is the least understood. The mode of transmission for this disease is still unclear and there is no effective cure. The most widely accepted theory is that the mycobacteria enter through the body through the skin at the site of a penetrating or blunt trauma. The first indications of Buruli ulcer begin with a firm painless nodule just below the surface of the skin and may be mistaken for a common boil. However, cyto-toxins released by the mycobacteria eventually destroy subcutaneous tissue, leading to aggressive damage of surrounding soft tissue and bone. Since the nodules are not painful until the disease progresses, early detection is rare. Buruli ulcer is found nearly equally in both men and women who live in rural topical areas near rivers or wetlands. However, the highest frequencies of infection are in children under 15 years of age. It is most prevalent in West Africa, but has been found in areas of Asia, Latin America, and the Western Pacific.

Having learned that sources of water provide a potential medium for the transmission of the mycobacteria, my purpose was to study high incidence villages versus low incidence villages that used the same water source. I hypothesized that those villages higher in the surrounding hills would have significantly less cases of Buruli ulcer than the villages using the same river further downstream in the lowlands. In the Ga District, there are several rivers that come from the hills and fan out providing the necessary water that many villagers need for drinking, cooking, bathing, and washing clothes. I chose to observe three villages in the lowlands that relied on the Nsaki River and two villages upriver in the hills that used the same river. The three bottom villages were: Oshiuman, Odumasi, and Nsakina. The upper villages on the river were: Katapor, and Mayera. In each village, I thoroughly mapped out all of their water sources. Typically, their water comes from either areas of the river, ground wells, or stagnant pools. In some instances they only have access to the river. In addition to mapping their sources of water, I also identified anyone that had Buruli ulcer at the present time or in the past. I also, spoke with the villagers to get their ideas of the disease concerning its cause and how they treated it. This same cultural and cartographical approach was carried out in each village.

Beginning in the lowlands, each of the three villages shared the same sad news. There were many cases of Buruli ulcer—several with severe late ulcerations. There were an average of 15 cases of Buruli ulcer in each of the villages. All three villages had access to the river, ground wells, and stagnant pools. I learned that other humanitarian groups in the past came into the rural areas and dug ground wells so the villagers did not have to drink the dirty river water. However, I observed that the majority of the villages would not use them because they said the water was too “salty.” Apparently the mineral content was high enough to give an unpleasant taste and make washing and bathing tough. The people preferred to fetch water from the river or from the stagnant pools. Both of these sources have one key element in common. Since it is the lowlands, the water has nowhere to run off and sits for a long time. The river, quickly flowing from the hills arrives in the low areas, spreads out, and looks like a big swamp.

Aside from the stagnant rivers, I observed that probably one of the biggest promoters of the disease are the numerous excavated sand areas that sit with stagnant rainwater. In the past ten years, these low areas have been heavily dredged of their topsoil, which is mainly sand. Local farmers, in desperate measures to make a quick income, sell their land to dredging companies who come and remove the top layer of earth to sell to cement companies in the capital. When they are finished, they leave behind large patches of barren land with a new layer of clay dirt exposed. The clay earth is less porous and therefore does not let the water filter down as easily as sand. This causes the stagnant water. With eager eyes (especially in the hot weather), children (especially) and adults use these pools for swimming, drinking, bathing, fishing, and washing clothes. If the hypothesis is true regarding water being a medium for transmission of the disease, then it directly correlates to a higher incidence of the disease in the lowlands.

After several weeks in the low areas, I left for Katapor—a very small village nestled in the green hills of the Ga District. If the hypothesis was true, there should be significantly fewer cases of Buruli ulcer in the hills because of a faster flowing river source. I was quite happy to find that in the entire village, only two people had the disease and both of them had contracted it before moving to Katapor. I mapped out all the sources of water and was pleased to find that a vast majority of the village used well water for everything, and only on rare occasion drank from the Nsaki River. They did not complain of a “salty” taste in the well water since the rocky earth allowed for a better filtration of the water. The other village I observed was Mayera. I expected to find similar results there since it was a slightly larger village just right across the Nsaki River. However, I was quite astonished as I walked around in the village. By just strolling through the village, I saw more than 15 children with active cases of Buruli ulcer. I later learned that this village did not have well water, which meant everyone had to rely on the Nsaki River as the main source for all of their water. From this, one would be quick to deduce that if both villages have the same lifestyle except where they get their water, then this difference is directly related to the transmission of the disease. It seemed obvious that the Nsaki River had a significant role in Mayera having more cases of Buruli than Katapor. However, this completely disproved my hypothesis that the villages in the hills (where the water is not stagnant) had lower incidence of the disease than those down river. I was left with the question: Why does Mayera, a village with a fast flowing river have so many cases?—especially when the WHO had filtered hundreds of gallons of water and did not find a significant amount of mycobacterium ulcerans. This proved to be a wonderful opportunity in which my information was compiled with that of the other researchers from HART. Together, the work will help the WHO in knowing how to better educate villagers in early prevention of the disease. It will also help Ghanaian officials to have a more accurate account of the seriousness of this emerging disease in their country.