Leprosy in wild chimpanzees.

Humans are considered as the main host for Mycobacterium leprae1, the aetiological agent of leprosy, but spillover has occurred to other mammals that are now maintenance hosts, such as nine-banded armadillos and red squirrels2,3. Although naturally acquired leprosy has also been described in captive nonhuman primates4-7, the exact origins of infection remain unclear. Here we describe leprosy-like lesions in two wild populations of western chimpanzees (Pan troglodytes verus) in Cantanhez National Park, Guinea-Bissau and Taï National Park, Côte d'Ivoire, West Africa. Longitudinal monitoring of both populations revealed the progression of disease symptoms compatible with advanced leprosy. Screening of faecal and necropsy samples confirmed the presence of M. leprae as the causative agent at each site and phylogenomic comparisons with other strains from humans and other animals show that the chimpanzee strains belong to different and rare genotypes (4N/O and 2F). These findings suggest that M. leprae may be circulating in more wild animals than suspected, either as a result of exposure to humans or other unknown environmental sources.

The paediatric participation scale measuring participation restrictions among former Buruli Ulcer patients under the age of 15 in Ghana and Benin: Development and first validation results.

BACKGROUND: Buruli Ulcer (BU) is a neglected tropical disease caused by Mycobacterium ulcerans. Former BU patients may experience participation restrictions due to physical limitations, stigmatization and other social factors. A scale that measures participation restrictions among children, who represent almost half of the affected population, has not been developed yet. Here, we present the development of a scale that measures participation restrictions in former BU paediatric patients, the psychometric properties of this scale and the scales' results. METHODS: Items were selected and a scale was developed based on interviews with health care workers and former BU patients in and around the BU treatment centre in Lalo, Benin. Construct validity was tested using six a priori formulated hypotheses. Former BU patients under 15 years of age who received treatment in one of the BU treatment centres in Ghana and Benin between 2007-2012 were interviewed. RESULTS: A feasible 16-item scale that measures the concept of participation among children under 15 years of age was developed. In total, 109 (Ghana) and 90 (Benin) former BU patients were interviewed between 2012-2017. Five construct validity hypotheses were confirmed of which 2 hypotheses related to associations with existing questionnaires were statistically significant (p<0.05). In Ghana 77% of the former patients had a Paediatric Participation (PP) scale score of 0 compared to 22% in Benin. More severe lesions related to BU were seen in Benin. Most of the reported participation problems were related to sports, mainly in playing games with others, going to the playfield and doing sports at school. CONCLUSION: The preliminary results of the PP-scale validation are promising but further validation is needed. The developed PP-scale may be valid for use in patients with more severe BU lesions. This is the first research to confirm that former BU patients under 15-year face participation restrictions in important aspects of their lives.

Delayed versus standard assessment for excision surgery in patients with Buruli ulcer in Benin: a randomised controlled trial.

BACKGROUND: Surgical intervention was once the mainstay of treatment for Buruli ulcer disease, a neglected tropical disease caused by Mycobacterium ulcerans. Since the introduction of streptomycin and rifampicin for 8 weeks as standard care, surgery has persisted as an adjunct therapy, but its role is uncertain. We investigated the effect of delaying the decision to operate to 14 weeks on rates of healing without surgery. METHODS: In this randomised controlled trial, we enrolled patients aged 3 years or older with confirmed disease at one hospital in Lalo, Benin. Patients were randomly assigned (1:1) to groups assessing the need for excision surgery 8 weeks (standard care) or 14 weeks after initiation of antimicrobial treatment. The primary endpoint was the number of patients healed without the need for surgery (not including skin grafting), assessed in all patients in follow-up at 50 weeks (or last observation for those healed for >10 weeks). A doctor masked to treatment assignment checked the indications for surgery according to predefined criteria. This study is registered with ClinicalTrials.gov, number NCT01432925. FINDINGS: Between July 1, 2011, and Jan 15, 2015, 119 patients were enrolled, with two patients per group lost to follow-up. 55 (96%) of 57 participants in the delayed-decision group and 52 (90%) of 58 participants in the standard-care group had healed lesions 1 year after start of antimicrobial treatment (relative risk [RR] 1·08, 95% CI 0·97-1·19). 37 (67%) of 55 patients in the delayed-decision group had their lesions healed without surgical intervention, as did 25 (48%) of 52 in the standard-care group (RR 1·40, 95% CI 1·00-1·96). The time to heal and residual functional limitations did not differ between the two groups (median time to heal 21 weeks [IQR 10-27] in the delayed-decision group and 21 weeks [10-39] in the standard-care group; functional limitations in six [11%] of 57 and three [5%] of 58 patients; p=0·32). Postponing the decision to operate resulted in reduced median duration of hospitalisation (5 days [IQR 0-187] vs 131 days [0-224]; p=0·024) and wound care (153 days [IQR 56-224] vs 182 days [94-307]; p=0·036). INTERPRETATION: In our study, patients treated for Buruli ulcer benefited from delaying the decision to operate. Even large ulcers can heal with antibiotics alone, without delaying healing rate and without an increase in residual functional limitations. FUNDING: NWO-VENI grant 241500, BUG Foundation, and UBS OPTIMUS.

Clinical considerations on Buruli ulcer employing two molecular tests for the detection of Mycobacterium ulcerans in 100 skin biopsies.

OBJECTIVES: Buruli ulcer (BU) is an infected cutaneous lesion, the etiological agent of which is Mycobacterium ulcerans. Diagnosis is confirmed by the identification of acid-fast bacilli and culture. In clinically suspicious forms with negative bacteriological or Ziehl-Neelsen (ZN) findings, molecular tests are used. This study compared the concordance of nested polymerase chain reaction (PCR) (targeting IS2404) and PCR (targeting IS2606) in different clinical situations. METHODS: A total of 57 samples were sourced from 39 BU patients. Control samples (n = 43) were obtained from non-BU ulcers in 38 patients. Samples were divided into two pieces and submitted to, respectively, histological examination and ZN staining, and PCR. Subsamples submitted to PCR were divided and submitted to nested PCR IS2404 and PCR IS2606, respectively. RESULTS: Of the 57 BU biopsies, positive results were obtained by nested PCR in 18 (31.6%) and by IS2606 PCR in 37 (64.9%) cases. Sequencing of the positive samples confirmed the specificity of amplicons in all nested PCR samples and in 26 of 37 (70.2%) samples positive to IS2606. Hence, nested PCR was more specific (100% vs. 93%) and less sensitive (32% vs. 46%) than IS2606 PCR. In the BU samples, nested PCR was negative in 15 instances, and IS2606 PCR was negative in 11 instances in which ZN histology had been positive (false negatives). Both PCRs were positive in six ZN-negative smears. CONCLUSIONS: We considered 57 samples from 39 BU patients in various clinical stages and at different times after the beginning of therapy. These provided positive results in 18 cases with IS2404 nested PCR and in 37 cases with PCR IS2606; only 26 of the latter remained positive subsequent to sequencing. Hence, even if IS2404 PCR is considered more specific, in subjects who appear to fail to respond to therapy, it is advisable to also carry out IS2606 PCR. A possible interpretation of the discordance between the two techniques due to unavoidable technical errors as well as to different sensitivity of the two tests at M. ulcerans DNA low concentration (i.e. in recent infection and in well-treated cases) is discussed.

Association of HIV infection and Mycobacterium ulcerans disease in Benin.

We investigated the association between Buruli ulcer and HIV by comparing the HIV-1/2 seroprevalence in a series of 426 Buruli ulcer patients and a sample of 613 residents of southern Benin. The overall HIV prevalence was 2.6% (11/426) among patients and 0.3% among controls (2/613), giving an odds ratio for the association between HIV and Buruli ulcer of 8.1 (95% confidence interval = 1.8-75; P = 0.003).

Setting up a national reference laboratory for Buruli ulcer: the case of Benin.

OBJECTIVE: To report the experience of Benin, where Buruli ulcer (BU) is endemic, in the implementation of diagnostic laboratory services. METHODS AND RESULTS: There has been a gradual introduction of biologic diagnostic activities for BU comprising (1) training of a laboratory technician in a highly experienced reference laboratory; (2) acquiring indispensable laboratory start-up materials; (3) progressive development of diagnostic laboratory activities; (4) regular external quality assessment with an experienced reference laboratory and (5) decentralization of activities to various clinical diagnostic and treatment centres for BU in Benin. CONCLUSION: Setting up a reference laboratory for BU is a continuous process, which necessitates motivated personnel and the cooperation of an experienced external reference laboratory.

Environmental and health-related risk factors for Mycobacterium ulcerans disease (Buruli ulcer) in Benin.

We conducted a case-control study to investigate the association between Buruli ulcer (BU) and environmental- and health-related behaviors in southern Benin. Hospital BU cases (N = 324) and sex- and age-matched neighborhood controls (N = 1,173) answered a questionnaire. Regular use of soap for washing, treating injuries with soap or antibiotic powder, and frequent contact with flowing water appeared protective against BU.

Association between haemoglobin variants S and C and Mycobacterium ulcerans disease (Buruli ulcer): a case-control study in Benin.

Risk factors for Buruli ulcer (BU) are poorly understood. We conducted a case-control study in southern Benin to investigate the association between haemoglobin variants S or C and BU, and particularly the association between haemoglobinopathies HbSS/SC and BU osteomyelitis. We compared the haemoglobin genotype of 179 patients with BU and 44 with BU osteomyelitis to that of 242 community controls. We found no evidence of an increased risk of BU according to the presence of haemoglobin variants S and/or C [odds ratio adjusted for sex, age, region of residence and ethnicity: 1.24 (95% CI: 0.80-1.93), P = 0.34]. Haemoglobin variants S and C are unlikely to play a role in the BU burden. However, haemoglobinopathies HbSS/SC were more frequent among BU osteomyelitis patients than among controls (6.8% vs. 1.0%, Fisher's exact P-value = 0.045), which may suggest that those disorders facilitate growth of Mycobacterium ulcerans in the bone matrix.