# Risk factors for Buruli ulcer disease in Ghana: A matched case-control study in four selected endemic districts of Eastern and Oti Regions

## TL;DR

This study in Ghana found that farming without protective clothing and living near waterbodies increase the risk of Buruli ulcer disease, while being married and using alcohol on injuries may reduce the risk.

## Contribution

The study identifies new risk and protective factors for Buruli ulcer disease using an improved 1:2 matched case-control design in endemic regions of Ghana.

## Key findings

- Farming without adequate protective clothing increases the odds of Buruli ulcer disease (aOR = 3.02).
- Living near waterbodies is associated with a higher risk of Buruli ulcer disease (aOR = 4.45).
- Being married and applying alcohol to injuries are associated with reduced odds of Buruli ulcer disease (aORs = 0.32 and 0.17).

## Abstract

Buruli ulcer disease (BUD) remains a poorly understood neglected tropical disease (NTD). The 2021–2030 WHO NTD Roadmap prioritises addressing knowledge gaps in BUD transmission and calls for the need to better understand the factors contributing to disease occurrence. In Ghana, reported BUD cases declined from over 600 in 2018 to 81 in 2023. While previous case-control studies in Ghana have used a 1:1 matching ratio, this study examined potential risk factors for BUD in four endemic districts using an improved methodological approach.

A community-based 1:2 matched case-control study was conducted in four BUD-endemic districts (Akwapim South, Akwapim North-Okere, Jasikan, and Biakoye) in the Eastern and Oti Regions of Ghana. Seventy (70) BUD cases and 140 community controls were recruited and matched by age (±5 years), sex, and place of residence. Data on socio-demographic, behavioural, environmental, water use, and injury management factors were collected by trained research assistants using semi-structured questionnaires designed with KoboCollect. Multivariable conditional logistic regression produced adjusted odds ratios (aORs) with 95% confidence intervals at p < 0.05.

In the multivariable analysis, farming without adequate protective clothing (aOR = 3.02, 95% CI: 1.03–8.89) and living near waterbodies (aOR = 4.45, 95% CI: 1.46–13.55) were associated with increased odds of BUD. Being married (aOR = 0.32, 95% CI: 0.13–0.78) and applying alcohol to injury sustained (aOR = 0.17, 95% CI: 0.03–0.83) reduced the odds of BUD.

Farming without adequate protective clothing and proximity to waterbodies were the main risk factors for BUD in endemic districts in Ghana. In contrast, being married and practising injury care using alcohol appeared protective. The Ghana Health Service should promote the consistent use of protective clothing during agricultural activities, raise awareness among communities living near waterbodies, and encourage proper injury care practices to reduce the risk of BUD.

Buruli ulcer disease is a bacterial infection that causes chronic skin ulcers and often leads to long-term disability if not treated early. Despite its public health impact, the exact mode of transmission remains unclear. This study was carried out in four districts in Ghana where Buruli ulcer is common, to better understand behaviours and environmental factors that may still be putting people at risk of infection. Using a 1:2 matched case-control approach, the study found that people who farmed without adequate protective clothing and those who lived close to waterbodies were more likely to develop BUD. On the other hand, individuals who were married and those who applied alcohol to injuries were less likely to get the disease. These findings support practical, community-level preventive strategies such as promoting the use of protective gears during farming and encouraging proper injury care, which could help reduce the burden of BUD in areas where the disease is common.