Buruli ulcer in Nigeria: results of a pilot case study in three rural districts

Systematic review: Global host range, case fatality and detection rates of Mycobacterium ulcerans in humans and potential environmental sources

Fundamental aspects of the epidemiology and ecology of Mycobacterium ulcerans (MU) infections including disease burden, host range, reservoir, intermediate hosts, vector and mode of transmission are poorly understood. Understanding the global distribution and burden of MU infections is a paramount to fight against Buruli ulcer (BU). Four databases were queried from inception through December 2023. After critical review of published resources on BU, 155 articles (645 records) published between 1987 and 2023 from 16 countries were selected for this review. Investigating BU in from old endemic and new emerging foci has allowed detection of MU in humans, animals, plants and various environmental samples with prevalence from 0 % up to 100 % depending of the study design. A case fatality rate between 0.0 % and 50 % was described from BU patients and deaths occurred in Central African Republic, Gabon, Democratic Republic of the Congo, Burkina Faso and Australia. The prevalence of MU in humans was higher in Africa. Nucleic Acid Amplification Tests (NAAT) and non-NAAT were performed in > 38 animal species. MU has been recovered in culture from possum faeces, aquatic bugs and koala. More than 7 plant species and several environmental samples have been tested positive for MU. This review provided a comprehensive set of data on the updates of geographic distribution, the burden of MU infections in humans, and the host range of MU in non-human organisms. Although MU have been found in a wide range of environmental samples, only few of these have revealed the viability of the mycobacterium and the replicative non-human reservoirs of MU remain to be explored. These findings should serve as a foundation for further research on the reservoirs, intermediate hosts and transmission routes of MU.

Qualitative study of the stigma associated with the lived experiences of Buruli ulcer disease among patients in Nigeria

BACKGROUND

Buruli ulcer disease (BUD) is a neglected tropical disease of the skin, subcutaneous tissue and bone caused by Mycobacterium ulcerans, with various disabling and stigmatising sequelae. Patients face a range of adverse impacts owing to the disease as most are unable to relate effectively with their communities, battling stigma and fear of discrimination. This study aimed to explore the stigma associated with the lived experiences of BUD in patients in Nigeria.

METHODS

This was a cross-sectional qualitative study that employed a focus group discussion (FGD) and key informant interviews in Enugu State, Nigeria. A random sampling of communities was followed by a purposive selection of FGD participants and key informants. A total of six key informants and eight FGD participants took part in the study. Data were collected over 6 wk from December 2022 to February 2023. The NVivo application was used to analyse transcripts and compute themes of quotes.

RESULTS

Patients experienced stigma owing to the condition. The most reported experiences by participants were shame and culpability, isolation and social exclusion, including maltreatment from family members.

CONCLUSIONS

Identifying the stigma experienced by patients owing to BUD helps in the provision of psychosocial management services and support for patients.

Seroprevalence, co-infection and risk of transmission of Hepatitis B and D virus among hospital attendees in two South-western states in Nigeria

Infection with both Hepatitis B (HBV) and D (HDV) virus causes more severe liver damage than HBV alone. Superinfections among chronic HBV infected cohorts often lead to HDV persistence with rapid progression to cirrhosis, necessitating continuous surveillance to determine their prevalence and relative contribution to liver pathology. A cross-sectional study among hospital outpatients in Ekiti and Osunstates was conducted using random sampling technique. Blood samples were collected from 410 participants and tested for HBV serological markers. All samples positive for HBsAg samples were tested for Hepatitis D virus antigen (HDAg), serum anti-HDV IgM, and serum anti-HDV IgG using enzyme-linked immunosorbent assay kits. The prevalence of HBV infection among the 410 samples was 12.4% (CI 9.5-15.9). Past HBV exposure was detected in 120 (29.2%), while 147(35.8%) were susceptible to HBV infection. Among the HBsAg positive individuals, 9.8% were hepatitis D antigen (HDAg) positive, while 3.9% and 1.9% were positive for IgG anti-HDV and IgM anti-HDV, respectively. Risk factors associated with HBV infections in this study were multiple sexual partners and sharing of sharp objects. Our investigation has verified the endemicity of HBV in Nigeria and revealed that HBV- HDV co-infection is highly prevalent in south-west Nigeria.

Perceived water-related risk factors of Buruli ulcer in two villages of south-central Côte d'Ivoire

BACKGROUND

Buruli ulcer, caused by Mycobacterium ulcerans, is a neglected tropical skin disease that is primarily endemic in West and Central Africa, including Côte d'Ivoire. Studies indicate that M. ulcerans infections are caused by contact with an environmental reservoir of the bacteria, governed by specific human biological conditions. Yet, the nature of this reservoir and the exact mode of transmission remain unknown.

METHODOLOGY

To identify ecologic risk factors of Buruli ulcer in south-central Côte d'Ivoire, we pursued a qualitative study matched with geo-referencing inquiry. Embedded in a broader integrated wound management research project, we (i) mapped households and water sources of laboratory confirmed Buruli ulcer cases and (ii) interviewed 12 patients and four health care workers to assess exposure to surface water and to deepen the understanding of perceived transmission pathways.

PRINCIPAL FINDINGS

Water availability, accessibility, and affordability were reported as key determinants for choosing water resources. Furthermore, perceived risks were related to environmental, structural, and individual factors. Despite the presence of improved water sources (e.g., drilled wells), communities heavily relied on unprotected surface water for a multitude of activities. The nearby Bandama River and seasonal waterbodies were frequently used for washing, bathing, and collection of water for drinking and cooking. Many residents also reported to cross the river on a daily basis for agricultural chores, and hence, are exposed to stagnant water during farming activities.

CONCLUSIONS/SIGNIFICANCE

Our study in two Buruli ulcer endemic villages in south-central Côte d'Ivoire revealed a wide range of water-related domestic activities that might expose people to an increased risk of contracting the disease. Environmental, biological, social, and cultural risk factors are closely interlinked and should be considered in future investigations of Buruli ulcer transmission. Active participation of the communities is key to better understand their circumstances to advance research and fight against Buruli ulcer and other neglected tropical diseases.

Methods and Approaches for Buruli Ulcer Surveillance in Africa: Lessons Learnt and Future Directions

Over 95% of the global burden of Buruli ulcer disease (BU) caused by Mycobacterium ulcerans occurs in equatorial Africa. National and sub-national programs have implemented various approaches to improve detection and reporting of incident cases over recent decades. Regional incidence rates are currently in decline; however, surveillance targets outlined in 2012 by WHO have been missed and detection bias may contribute to these trends. In light of the new 2030 NTD roadmap and disease-specific targets, BU programs are required to strengthen case detection and begin a transition towards integration with other skin-NTDs. This transition comes with new opportunities to enhance existing BU surveillance systems and develop novel approaches for implementation and evaluation.In this review, we present a breakdown and assessment of the methods and approaches that have been the pillars of BU surveillance systems in Africa: (1) Passive case detection, (2) Data systems, (3) Clinical training, (4) Active case finding, (5) Burden estimation, and (6) Laboratory confirmation pathways. We discuss successes, challenges, and relevant case studies before highlighting opportunities for future development and evaluation including novel data collection tools, risk-based surveillance, and integrated skin-NTD surveillance. We draw on both experience and available literature to critically evaluate methods of BU surveillance in Africa and highlight new approaches to help achieve 2030 roadmap targets.

Perspectives of buruli ulcer patients toward informed consent - An insight from Nigeria

Introduction:

Informed consent is a basic ethical requirement in situations involving sharing of patients' data. It supports and upholds the ethical principle of respect for persons and individual autonomy. For Buruli ulcer (BU) patients, associated stigma renders them vulnerable, hence the need for emphasis on additional protection by ensuring obtaining informed consent before third party use of their data. The authors therefore sought to determine willingness of these patients to give informed consent to the third party use of their data before and after treatment.

Methodology:

This cross-sectional study was carried out between February and August, 2019. The study involved BU patients from three endemic states in Nigeria. Data were collected using pretested, researcher-administered semi-structured questionnaires.

Results:

A total of 92 respondents participated in the study. The median age was 23.5 years (range 4–74 years) with the age group <15 years being the modal age group 36 (39.13%). About a quarter of the respondents (23.91%) had suffered some form of discrimination in the course of their disease. Majority 86 (93.48%) were favorably disposed to allowing the use of their data for donor drive, policy development, and teaching/training purposes. A significant greater proportion of respondents 90 (97.83%) were willing to give consent for the use of their oral interview as against pictures and videos both in the pre- and post-treatment periods.

Conclusion:

The present study provides evidence that majority of the respondents were positively inclined to give consent to use of their data by a third party. However, intrusion into privacy and anonymity were major concerns for the respondents.

Investigating barriers and challenges to the integrated management of neglected tropical skin diseases in an endemic setting in Nigeria

BACKGROUND

There is a dearth of experience in and evidence for cost-effective integrated community-based management of skin neglected tropical diseases (NTDs). The objective of this study was to assess the knowledge, attitude and care-seeking practices including self-care with a view to introducing appropriate community-based interventions for skin NTDs in an endemic setting in Southern Nigeria.

METHODS/PRINCIPAL FINDINGS

This exploratory study adopted a mixed-methods design consisting of cross-sectional surveys of community members and health workers using interviewer-administered questionnaires; and focus group discussions (FGDs) with community members, health care workers and patients with NTDs in Anambra State, Nigeria. The survey was completed by 353 community members (61.8% female) and 15 health care workers (100.0% female). A total of 52 individuals participated in six FGDs. Of the community members, 236 (66.9%) had heard or seen a case of leprosy; 324 (91.8%) and 131 (37.5%) had heard or seen a case of Buruli ulcer and lymphatic filariasis, respectively. Again, 213 (60.3%) of the respondents reported that the diseases were caused by witchcraft or curse. As regards prevention, 241 (68.3%) suggested avoiding handshake with affected persons. Up to 223 (63.2%) of respondents strongly agreed to the seriousness of skin NTDs in their community. Meanwhile, 272 (77.1%) of the respondents believed that the transmission of these skin NTDs can be prevented. Furthermore, 324 (91.7%) desired active community engagement for control of skin NTDs. Regarding community care seeking practices, 197 (55.8%) would first visit the health centre/hospital, followed by 91 (25.8%) traditional healer/herbalist and 35 (9.9%) pharmacy/patent medicine vendor if they develop a skin NTD. Overall, 332 (94.1%) of respondents expressed interest in being taught self-care practices for skin NTDs. Out of 15 healthcare workers, 13 (86.7%) were able to correctly diagnose two of these skin NTDs and 10 (66.7%) would encourage patients to practice self-care. Prominent themes in the FGDs were belief in witchcraft and herbal remedies; as well as the occurrence of physical, social and economic distress.

CONCLUSIONS

Our study helped quantify the information gaps that need to be addressed in order to create demand for integrated skin NTDs services in an endemic setting in Nigeria. Individual, structural and socioeconomic challenges to access and delivery of services were identified. Community and health care workers' empowerment and engagement through outreach and regular training, respectively may alleviate these challenges.

Global Epidemiology of Buruli Ulcer, 2010-2017, and Analysis of 2014 WHO Programmatic Targets

Buruli ulcer is a neglected tropical disease caused by Myocobacterium ulcerans; it manifests as a skin lesion, nodule, or ulcer that can be extensive and disabling. To assess the global burden and the progress on disease control, we analyzed epidemiologic data reported by countries to the World Health Organization during 2010–2017. During this period, 23,206 cases of Buruli ulcer were reported. Globally, cases declined to 2,217 in 2017, but local epidemics seem to arise, such as in Australia and Liberia. In 2013, the World Health Organization formulated 4 programmatic targets for Buruli ulcer that addressed PCR confirmation, occurrence of category III (extensive) lesions and ulcerative lesions, and movement limitation caused by the disease. In 2014, only the movement limitation goal was met, and in 2019, none are met, on a global average. Our findings support discussion on future Buruli ulcer policy and post-2020 programmatic targets.

Assessment of community knowledge, attitude, and stigma of Buruli ulcer disease in Southern Nigeria

Background

Poor knowledge can influence timely care-seeking among persons with Buruli ulcer disease (BUD).

Objectives

To assess community knowledge, attitude and stigma towards persons with BUD in endemic settings of Southern Nigeria.

Methods

This was a cross-sectional survey conducted among adult community members in four States of Southern Nigeria. A semi-structured interviewer-administered questionnaire was administered to all participants.

Results

Of 491 adults who completed the survey, 315 (64.2%) belonged to the ≤40 years age group, 257 (52.3%) were males and 415 (84.5%) had some formal education. The overall mean (SD) knowledge score was 5.5±2.3 (maximum 10). Only 172 (35.0%) of the participants had a good knowledge of BUD. A total of 327 (66.6%) considered BUD as a very serious illness. Also, there was a high-level of stigma against BUD patients; 372 (75.8%) of the participants felt compassion for and desire to help them, 77 (15.7%) felt compassion but tended to stay away from them, and 53 (10.8%) feared them because they may infect them with the disease. Having a formal education and ethnicity were independent predictors of good knowledge of BUD.

Conclusion

There is poor community knowledge of BUD in endemic settings of Southern Nigeria which influenced the attitude and perceptions of community members towards persons with BUD

Perceived causes and risk factors of Buruli ulcer among patients at Agogo Presbyterian hospital in Ashanti Region of Ghana

Objective

The incidence of Buruli ulcer has been recorded in about 30 countries globally and Africa seems to be the most affected area. The study sought to determine perceived causes and risk factors of Buruli ulcer among patients who visit the Agogo hospital in Asante-Akim North District in the Ashanti region of Ghana. A descriptive study design was adopted using a simple random sampling technique to select 400 patients attending The Presbyterian Hospital at Agogo. Data was collected using a structured questionnaire and analysed using SPSS version 16.0.

Results

Buruli ulcer was perceived as a disease caused by witchcraft (38%), enemies (15%), as well as not pouring libation or praying (16%). Also, increased appetite (30%), oedema or swelling on the skin (29%) and over weight (23%) was perceived as signs and symptoms of Buruli ulcer and a section of the respondents (53%) did not know any risk factor. The age of respondents, gender and level of education were found to determine knowledge of Buruli ulcer (P ≤ .05). Public Educations and campaigns should focus on causes and risk factors to ensure that there is adequate knowledge among the general public on Buruli ulcer.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3172-5) contains supplementary material, which is available to authorized users.

PCR detection of Mycobacterium ulcerans-significance for clinical practice and epidemiology

Introduction: Buruli ulcer (BU) is a neglected disease which has been reported from mostly impoverished, remote rural areas from 35 countries worldwide. BU affects skin, subcutaneous tissue, and bones, and may cause massive tissue destruction and life-long disabilities if not diagnosed and treated early. Without laboratory confirmation diagnostic and treatment errors may occur. This review describes the application of IS2404 PCR, the preferred diagnostic test, in the area of individual patient management and clinico-epidemiological studies. Areas covered: A Medline search included publications on clinical sample collection, DNA extraction, and PCR detection formats of the past and present, potential and limitations of clinical application, as well as clinico-epidemiological studies. Expert commentary: A global network of reference laboratories basically provides the possibility for PCR confirmation of 70% of all BU cases worldwide as requested by the WHO. Keeping laboratory confirmation on a constant level requires continuous outreach activities. Among the potential measures to maintain sustainability of laboratory confirmation and outreach activities are decentralized or mobile diagnostics available at point of care, such as IS2404-based LAMP, which complement the standard IS2404-based diagnostic tools available at central level.

Perception and incidence of Buruli ulcer in Ogun State, South West Nigeria: intensive epidemiological survey and public health intervention recommended

Introduction

Buruli ulcer (BU) is a highly ranked neglected tropical disease (NTD) of global health importance with increasing incidence in sub-Saharan Africa yet there is paucity of information on the epidemiology of BU in Nigeria. Incidentally, highly BU endemic Benin Republic shares proximity with Nigeria. This study was carried out to establish presence of BU and ascertain the level of BU perception among rural populace in Ogun State, south-west Nigeria.

Methods

Secondary data (2009-2012) on incidence of BU was collected from a reference hospital. A cross-sectional survey using structured questionnaire administered to rural people and healthcare practitioners was conducted in three purposively chosen Local Government Areas (LGAs) in Ogun State based on unpublished reports of BU presence.

Results

Data collected revealed 27 hospital confirmed BU cases between 2009-2012 across four LGAs (Obafemi Owode, Abeokuta North, Yewa North and Yewa South) while 14%(21/150) chronic ulcers (suspected to be BU) were discovered during the cross-sectional survey carried out in Odeda, Yewa South and North LGAs. Healthcare practitioners 63.6% (42/66) and 54.7% (82/150) rural people demonstrated poor level of BU perception respectively.

Conclusion

This study provides evidence that BU exists in Ogun State and evaluates the poor perception that the affected rural populace has on the disease. This pilot study presents baseline information on BU in a rural setting in Ogun State South-west Nigeria hence the vital need for prompt public health involvement and further research on the epidemiology of BU.

Assessment of health care workers' knowledge, attitude and risk perception of Buruli ulcer disease in Southern Nigeria

Background

Poor knowledge of health care workers may be responsible for the under-diagnosis and low notification of Buruli ulcer (BU) in high-burden settings. This study assessed health care workers' knowledge, attitude and risk perception of BU in Southern Nigeria.

Methods

We conducted a cross-sectional survey among 186 health care workers recruited from 58 health facilities in four states of Southern Nigeria. A semi-structured interviewer-administered questionnaire was administered to all participants.

Results

The overall mean knowledge score was 8.8±2.7 (maximum 15). Only 29.0% (54/186) of the respondents had a good knowledge of BU. The mean (SD) attitude score was 4.5±1.2 (maximum 6). Also, 61.3% (114/) of the respondents had a good attitude towards BU. The overall mean (SD) risk perception score was 2.6±1.3 (maximum 5). Only 26.3% (49/) of the respondents had a good risk perception of BU disease. Previous training was an independent predictor of good knowledge (aOR 4.6), good attitude (aOR 3.8) and good risk perception (aOR 2.9) to BU.

Conclusions

Health care workers in endemic settings of Nigeria have poor knowledge of and poor risk perception of BU disease. Training of health care workers is recommended to address the identified gaps to ensure earlier diagnosis and referral to specialist centres.

Report of a series of 82 cases of Buruli ulcer from Nigeria treated in Benin, from 2006 to 2016

Background

Nigeria is one of the countries endemic for Buruli ulcer (BU) in West Africa but did not have a control programme until recently. As a result, BU patients often access treatment services in neighbouring Benin where dedicated health facilities have been established to provide treatment free of charge for BU patients. This study aimed to describe the epidemiological, clinical, biological and therapeutic characteristics of cases from Nigeria treated in three of the four treatment centers in Benin.

Methodology/Principal findings

A series of 82 BU cases from Nigeria were treated in three centres in Benin during 2006–2016 and are retrospectively described. The majority of these patients came from Ogun and Lagos States which border Benin. Most of the cases were diagnosed with ulcerative lesions (80.5%) and WHO category III lesions (82.9%); 97.5% were healed after a median hospital stay of 46 days (interquartile range [IQR]: 32–176 days).

Conclusions/Significance

This report adds to the epidemiological understanding of BU in Nigeria in the hope that the programme will intensify efforts aimed at early case detection and treatment.

Buruli ulcer (BU) is a neglected tropical disease that mainly affects the skin. The disease results from infection with Mycobacterium ulcerans, an environmental bacterium. In Benin, the BU treatment centres usually receive patients from Nigeria. In 2014, a study from one of the treatment centres (CDTUB, Pobe) which borders south-western Nigeria reported on a cohort of 127 PCR-confirmed cases between 2005 and 2013. We describe the epidemiological, clinical, biological and therapeutic characteristics of BU cases from Nigeria treated in the three other CDTUBs.

Increased Severity and Spread of Mycobacterium ulcerans, Southeastern Australia

Reported cases of Mycobacterium ulcerans disease (Buruli ulcer) have been increasing in southeastern Australia and spreading into new geographic areas. We analyzed 426 cases of M. ulcerans disease during January 1998–May 2017 in the established disease-endemic region of the Bellarine Peninsula and the emerging endemic region of the Mornington Peninsula. A total of 20.4% of cases patients had severe disease. Over time, there has been an increase in the number of cases managed per year and the proportion associated with severe disease. Risk factors associated with severe disease included age, time period (range of years of diagnosis), and location of lesions over a joint. We highlight the changing epidemiology and pathogenicity of M. ulcerans disease in Australia. Further research, including genomic studies of emergent strains with increased pathogenicity, is urgently needed to improve the understanding of this disease to facilitate implementation of effective public health measures to halt its spread.

Buruli Ulcer, a Prototype for Ecosystem-Related Infection, Caused by Mycobacterium ulcerans

Buruli ulcer is a noncontagious disabling cutaneous and subcutaneous mycobacteriosis reported by 33 countries in Africa, Asia, Oceania, and South America. The causative agent, Mycobacterium ulcerans, derives from Mycobacterium marinum by genomic reduction and acquisition of a plasmid-borne, nonribosomal cytotoxin mycolactone, the major virulence factor. M. ulcerans-specific sequences have been readily detected in aquatic environments in food chains involving small mammals. Skin contamination combined with any type of puncture, including insect bites, is the most plausible route of transmission, and skin temperature of <30°C significantly correlates with the topography of lesions. After 30 years of emergence and increasing prevalence between 1970 and 2010, mainly in Africa, factors related to ongoing decreasing prevalence in the same countries remain unexplained. Rapid diagnosis, including laboratory confirmation at the point of care, is mandatory in order to reduce delays in effective treatment. Parenteral and potentially toxic streptomycin-rifampin is to be replaced by oral clarithromycin or fluoroquinolone combined with rifampin. In the absence of proven effective primary prevention, avoiding skin contamination by means of clothing can be implemented in areas of endemicity. Buruli ulcer is a prototype of ecosystem pathology, illustrating the impact of human activities on the environment as a source for emerging tropical infectious diseases.

Diagnosis delay and duration of hospitalisation of patients with Buruli ulcer in Nigeria

BACKGROUND

Delayed diagnosis of Buruli ulcer can worsen clinical presentation of the disease, prolong duration of management, and impose avoidable additional costs on patients and health providers. We investigated the profile, delays in diagnosis, duration of hospitalisation, and associated factors among patients with Buruli ulcer in Nigeria.

METHODS

This was a prospective cohort study of patients with Buruli ulcer who were identified from a community-based survey. Data on the patients' clinical profile, delays in diagnosis and duration of hospitalisation were prospectively collected.

RESULTS

Of 145 patients notified, 125 (86.2%) were confirmed by one or more laboratory tests (81.4% by PCR). The median age of the patients was 20 years, 88 (60.7%) were >15years old and 85 (58.6%) were females. In addition, 137 (94.5%) were new cases, 119 (82.1%) presented with ulcers and 110 (75.9%) had lower limb lesions. The mean time delay to diagnosis was 50.6 (±101.9) weeks. The mean duration of hospitalisation was 108 (±60) days. Determinants of time delay to diagnosis were higher disease category (p=0.001) and laboratory confirmation of disease (p=0.02). Determinants of longer hospitalisation were; multiple lesions (p=0.035), and having functional limitation at diagnosis and undertaking surgery (p=0.003).

CONCLUSIONS

Patients with Buruli ulcer have very long time delays to diagnosis and long hospitalisation during treatment. This calls for early case-finding and improved access to Buruli ulcer services in Nigeria.