Comparison of the prevalence rates of HIV infection between men who have sex with men (MSM) and men in the general population in sub-Saharan Africa: a systematic review and meta-analysis.

BACKGROUND: According to the 2015 report of the Joint United Nations Program on Human Immunodeficiency Virus (HIV) and Acquired Immune Deficiency Syndrome (AIDS), the prevalence rates of HIV infection among men who have sex with men (MSM) varied from 6 to 37% depending on the country, far exceeding the national prevalence rates. The present study on HIV infection among men who have sex with men in sub-Saharan Africa was conducted to describe the different sampling methods used to identify this target population and compare the prevalence rates of HIV infection among MSM to that of men in the general population. METHODS: The selection of studies to be included was carried out in the principal electronic databases. The 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) directives were used throughout the entire process. Bias evaluation was performed using the Mixed Methods Appraisal Tool. For each country, HIV prevalence values in both groups were calculated. A prevalence ratio was also calculated to compare the prevalence rates of the two groups. RESULTS: Seventeen articles were selected. Most of the studies (82.35%) used the Respondent-Driven Sampling method. The average prevalence rate was 17.81% (range: 3.7-33.46) for MSM and 6.15% (range: 0.5-19.7) for men in the general population. Overall, the human HIV prevalence rate was 4.94 times higher among MSM than among men in the general population (95%CI: 2.91-8.37). The western and central regions of Africa, as well as low-prevalence countries (prevalence < 1%), had very high prevalence ratios: 14.47 (95% CI: 9.90-21.13) and 28.49 (95% CI: 11.47-72.71), respectively. CONCLUSION: MSM are at higher risk of HIV infection than men in the general population. The prevalence ratios are particularly elevated in West and Central Africa as well as in low-prevalence countries. Close monitoring of the situation, research and preventive measures are essential to control the epidemic amongst MSM.

Functional limitations after surgical or antibiotic treatment for Buruli ulcer in Benin.

Almost half of patients have functional limitations after treatment of Buruli ulcer disease. Antibiotic treatment (along with surgery) was introduced in the National Program for Buruli ulcer in Benin in 2005. The aim of this study was to compare functional limitations in patients who were treated by antibiotics, surgery, or both, using a validated questionnaire. One hundred seventy-nine former patients in Lalo, Benin were retrieved and interviewed in their village. Hospital records were used to gather data about size of lesion at presentation and treatment provided. No significant differences in resulting functional limitations were found between the different treatments. Larger lesions (> 15 cm cross-sectional diameter) at presentation; lesions on a joint, muscular atrophy, and amputation were all associated with a higher risk for functional limitations. Advantages of antibiotic treatment may involve other domains, like costs of treatment or a change in help-seeking behavior.

Healthcare seeking behaviour for Buruli ulcer in Benin: a model to capture therapy choice of patients and healthy community members.

Buruli ulcer is a devastating condition emerging in West Africa. We investigated why patients often report late to the hospital. Health seeking behaviour determinants and stigma were studied by in-depth interviews in patients treated in hospital (n=107), patients treated traditionally (n=46) of whom 22 had active disease, and healthy community control subjects (n=107). We developed a model capturing internal and external factors affecting decision making. With increasing severity, extent and duration of Buruli ulcer, a shift of influencing factors on health seeking behaviour appears to occur. Factors causing delay in presenting to hospital were the use of traditional medicine before presenting at the treatment centre; costs and duration of admission; disease considered not serious enough; witchcraft perceived as the cause of disease; and fear of treatment, which patients expected to be amputation. This study confirms the importance of self-treatment and traditional healing in this area. Our study was performed before antimicrobial treatment was introduced in Benin; we suggest that this model and the results from this analysis should be used as a baseline from which to measure the influence of the introduction of antimicrobial treatment on health seeking behaviour for Buruli ulcer in Benin.

A Landscape-based model for predicting Mycobacterium ulcerans infection (Buruli Ulcer disease) presence in Benin, West Africa.

Mycobacterium ulcerans infection (Buruli ulcer [BU] disease) is an emerging tropical disease that causes severe morbidity in many communities, especially those in close proximity to aquatic environments. Research and control efforts are severely hampered by the paucity of data regarding the ecology of this disease; for example, the vectors and modes of transmission remain unknown. It is hypothesized that BU presence is associated with altered landscapes that perturb aquatic ecosystems; however, this has yet to be quantified over large spatial scales. We quantified relationships between land use/land cover (LULC) characteristics surrounding individual villages and BU presence in Benin, West Africa. We also examined the effects of other village-level characteristics which we hypothesized to affect BU presence, such as village distance to the nearest river. We found that as the percent urban land use in a 50-km buffer surrounding a village increased, the probability of BU presence decreased. Conversely, as the percent agricultural land use in a 20-km buffer surrounding a village increased, the probability of BU presence increased. Landscape-based models had predictive ability when predicting BU presence using validation data sets from Benin and Ghana, West Africa. Our analyses suggest that relatively small amounts of urbanization are associated with a decrease in the probability of BU presence, and we hypothesize that this is due to the increased availability of pumped water in urban environments. Our models provide an initial approach to predicting the probability of BU presence over large spatial scales in Benin and Ghana, using readily available land use data.

Buruli ulcer disease prevalence in Benin, West Africa: associations with land use/cover and the identification of disease clusters.

BACKGROUND: Buruli ulcer (BU) disease, caused by infection with the environmental mycobacterium M. ulcerans, is an emerging infectious disease in many tropical and sub-tropical countries. Although vectors and modes of transmission remain unknown, it is hypothesized that the transmission of BU disease is associated with human activities in or around aquatic environments, and that characteristics of the landscape (e.g., land use/cover) play a role in mediating BU disease. Several studies performed at relatively small spatial scales (e.g., within a single village or region of a country) support these hypotheses; however, if BU disease is associated with land use/cover characteristics, either through spatial constraints on vector-host dynamics or by mediating human activities, then large-scale (i.e., country-wide) associations should also emerge. The objectives of this study were to (1) investigate associations between BU disease prevalence in villages in Benin, West Africa and surrounding land use/cover patterns and other map-based characteristics, and (2) identify areas with greater and lower than expected prevalence rates (i.e., disease clusters) to assist with the development of prevention and control programs. RESULTS: Our landscape-based models identified low elevation, rural villages surrounded by forest land cover, and located in drainage basins with variable wetness patterns as being associated with higher BU disease prevalence rates. We also identified five spatial disease clusters. Three of the five clusters contained villages with greater than expected prevalence rates and two clusters contained villages with lower than expected prevalence rates. Those villages with greater than expected BU disease prevalence rates spanned a fairly narrow region of south-central Benin. CONCLUSION: Our analyses suggest that interactions between natural land cover and human alterations to the landscape likely play a role in the dynamics of BU disease. For example, urbanization, potentially by providing access to protected water sources, may reduce the likelihood of becoming infected with BU disease. Villages located at low elevations may have higher BU disease prevalence rates due to their close spatial proximity to high risk environments. In addition, forest land cover and drainage basins with variable wetness patterns may be important for providing suitable growth conditions for M. ulcerans, influencing the distribution and abundance of vectors, or mediating vector-human interactions. The identification of disease clusters in this study provides direction for future research aimed at better understanding these and other environmental and social determinants involved in BU disease outbreaks.

Factors associated with functional limitations and subsequent employment or schooling in Buruli ulcer patients.

OBJECTIVES: To evaluate former Buruli ulcer disease (BUD) patients to assess the factors associated with functional limitations and subsequent employment or schooling. METHODS: The previously validated Buruli ulcer functional limitation score (BUFLS) questionnaire and interviews about educational and professional consequences incurred by BUD. RESULTS: Of 638 participants, 362 (57%) had a functional limitation after a median period of almost 4 years after treatment for BUD. A lesion on a joint, older age, female gender, a lesion on a distal part of an extremity and a persistent wound were found to be independent risk factors for stopping work or education. The same risk factors applied to the development of a functional limitation. Both functional limitations and financial difficulties due to BUD disease often led to job loss and school dropout. CONCLUSIONS: Rehabilitation programmes are urgently needed to diminish the suffering from the functional limitations and employment or schooling problems caused by BUD.

Mycobacterium ulcerans disease.

Mycobacterium ulcerans disease (Buruli ulcer) is an important health problem in several west African countries. It is prevalent in scattered foci around the world, predominantly in riverine areas with a humid, hot climate. We review the epidemiology, bacteriology, transmission, immunology, pathology, diagnosis and treatment of infections. M. ulcerans is an ubiquitous micro-organism and is harboured by fish, snails, and water insects. The mode of transmission is unknown. Lesions are most common on exposed parts of the body, particularly on the limbs. Spontaneous healing may occur. Many patients in endemic areas present late with advanced, severe lesions. BCG vaccination yields a limited, relatively short-lived, immune protection. Recommended treatment consists of surgical debridement, followed by skin grafting if necessary. Many patients have functional limitations after healing. Better understanding of disease transmission and pathogenesis is needed for improved control and prevention of Buruli ulcer.

Reliability and validity of the Buruli ulcer functional limitation score questionnaire.

The reliability and validity of the earlier developed Buruli ulcer functional limitation score (BUFLS) questionnaire was assessed. Of 638 former Buruli ulcer patients (of 678 individuals examined), sufficient items on daily activities (>or= 13 of the 19) were applicable to calculate a score. To determine the validity, the functional limitation scores of the 638 individuals were compared with the global impression of the limitations, range of motion (ROM), and the social impact (change of occupation or education) of Buruli ulcer. To determine inter-observer reliability, the functional limitation score was reassessed in 107 participants within one and three weeks after the first interview by another interviewer and interpreter. Both global impression and ROM correlated well with the functional limitation scores (rho = 0.66 and rho = 0.61). The inter-observer reliability of 107 participants as measured by an intra-class correlation coefficient of 0.86 was very good. The functional limitation scores measured in the second assessment were significantly higher than in the first assessment. This should be taken into account when the functional limitation score is used for the individual patient. The BUFLS can be used as for between group comparisons of endpoints in clinical trials and in the planning of resources.

Development of a questionnaire assessing Buruli ulcer-induced functional limitation.

Buruli ulcer, a disease with long-term consequences, is emerging in west Africa. Thus, a functional limitation scoring system is needed to assess its nature and severity. A list of daily activities was developed for this disease. Following treatment of Buruli ulcer, persons in Benin (n = 47) and Ghana (n = 41) were investigated. Nineteen items were identified with good internal consistency. Participants (median age = 14 years) could not perform 23% of their daily activities. Twenty-nine participants did not have any functional limitation. The average limitation score was 31% in Benin and 15% in Ghana (P = 0.006). The mean limitation score in participants without visible contractures (n = 65) was 13%, whereas patients with visible contractures (n = 20) or an amputation (n = 3) had a score of more than 50%. Validity and reliability should be further analyzed to optimize the scale for use in individual evaluation, as an end point in intervention trials, and in planning of resources needed for the care of patients with functional limitations.