Protocol, rationale and design of BE-PEOPLE (Bedaquiline enhanced exposure prophylaxis for LEprosy in the Comoros): a cluster randomized trial on effectiveness of rifampicin and bedaquiline as post-exposure prophylaxis of leprosy contacts.

BACKGROUND: Leprosy is an ancient infectious disease with an annual global incidence of around 200,000 over the past decade. Since 2018, the World Health Organization (WHO) recommends single-dose rifampicin as post-exposure prophylaxis (SDR-PEP) for contacts of leprosy patients. The Post ExpOsure Prophylaxis for Leprosy (PEOPLE) trial evaluated PEP with a double dose of rifampicin in Comoros and Madagascar. Preliminary results of this trial show some reduction in leprosy incidence in intervention villages but a stronger regimen may be beneficial. The objective of the current Bedaquiline Enhanced ExpOsure Prophylaxis for LEprosy trial (BE-PEOPLE) is to explore effectiveness of a combination of bedaquiline and rifampicin as PEP. METHODS: BE-PEOPLE is a cluster-randomized trial in which 44 clusters in Comoros will be randomized to two study arms. Door-to-door screening will be conducted annually during four years, leprosy patients identified will be offered standard of care treatment. Based on study arm, contacts aged five years and above and living within a 100-meter radius of an index case will either receive bedaquiline (400-800 mg) and rifampicin (150-600 mg) or only rifampicin (150-600 mg). Contacts aged two to four years will receive rifampicin only. Household contacts randomized to the bedaquiline plus rifampicin arm will receive a second dose four weeks later. Incidence rate ratios of leprosy comparing contacts who received either of the PEP regimens will be the primary outcome. We will monitor resistance to rifampicin and/or bedaquiline through molecular surveillance in all incident tuberculosis and leprosy patients nationwide. At the end of the study, we will assess anti-M. leprae PGL-I IgM seropositivity as a proxy for the population burden of M. leprae infection in 8 villages (17,000 individuals) that were surveyed earlier as part of the PEOPLE trial. DISCUSSION: The COLEP trial on PEP in Bangladesh documented a reduction of 57% in incidence of leprosy among contacts treated with SDR-PEP after two years, which led to the WHO recommendation of SDR-PEP. Preliminary results of the PEOPLE trial show a lesser reduction in incidence. The BE-PEOPLE trial will explore whether reinforcing SDR-PEP with bedaquiline increases effectiveness and more rapidly reduces the incidence of leprosy, compared to SDR-PEP alone. TRIAL REGISTRATION: NCT05597280. Protocol version 5.0 on 28 October 2022.

Investigating drug resistance of Mycobacterium leprae in the Comoros: an observational deep-sequencing study.

BACKGROUND: Despite strong leprosy control measures, including effective treatment, leprosy persists in the Comoros. As of May, 2022, no resistance to anti-leprosy drugs had been reported, but there are no nationally representative data. Post-exposure prophylaxis (PEP) with rifampicin is offered to contacts of patients with leprosy. We aimed to conduct a countrywide drug resistance survey and investigate whether PEP led to the emergence of drug resistance in patients with leprosy. METHODS: In this observational, deep-sequencing analysis we assessed Mycobacterium leprae genomes from skin biopsies of patients in Anjouan and Mohéli, Comoros, collected as part of the ComLep (NCT03526718) and PEOPLE (NCT03662022) studies. Skin biopsies that had sufficient M leprae DNA (>2000 bacilli in 2 µl of DNA extract) were assessed for the presence of seven drug resistance-associated genes (ie, rpoB, ctpC, ctpI, folP1, gyrA, gyrB, and nth) using Deeplex Myc-Lep (targeted next generation deep sequencing), with a limit of detection of 10% for minority M leprae bacterial populations bearing a polymorphism in these genes. All newly registered patients with leprosy for whom written informed consent was obtained were eligible for inclusion in the survey. Patients younger than 2 years or with a single lesion on the face did not have biopsies taken. The primary outcome of our study was the proportion of patients with leprosy (ie, new cases, patients with relapses or reinfections, patients who received single (double) dose rifampicin-PEP, or patients who lived in villages where PEP was distributed) who were infected with M leprae with a drug-resistant mutation for rifampicin, fluoroquinolone, or dapsone in the Comoros. FINDINGS: Between July 1, 2017, and Dec 31, 2020, 1199 patients with leprosy were identified on the basis of clinical criteria, of whom 1030 provided a skin biopsy. Of these 1030 patients, 755 (73·3%) tested positive for the M leprae-specific repetitive element-quantitative PCR (qPCR) assay. Of these 755 patients, 260 (34·4%) were eligible to be analysed using Deeplex Myc-Lep. 251 (96·5%) were newly diagnosed with leprosy, whereas nine (3·4%) patients had previously received multidrug therapy. 45 (17·3%) patients resided in villages where PEP had been administered in 2015 or 2019, two (4·4%) of whom received PEP. All seven drug resistance-associated targets were successfully sequenced in 216 samples, 39 samples had incomplete results, and five had no results. No mutations were detected in any of the seven drug resistance-related genes for any patient with successfully sequenced results. INTERPRETATION: This drug resistance survey provides evidence to show that M leprae is fully susceptible to rifampicin, fluoroquinolones, and dapsone in the Comoros. Our results also show, for the first time, the applicability of targeted sequencing directly on skin biopsies from patients with either paucibacillary or multibacillary leprosy. These data suggest that PEP had not selected rifampicin-resistant strains, although further support for this finding should be confirmed with a larger sample size. FUNDING: Effect:Hope, The Mission To End Leprosy, the Fonds Wetenschappelijk Onderzoek, the EU.

Minimally invasive sampling to identify leprosy patients with a high bacterial burden in the Union of the Comoros.

The World Health Organization (WHO) endorsed diagnosis of leprosy (also known as Hansen's disease) entirely based on clinical cardinal signs, without microbiological confirmation, which may lead to late or misdiagnosis. The use of slit skin smears is variable, but lacks sensitivity. In 2017-2018 during the ComLep study, on the island of Anjouan (Union of the Comoros; High priority country according to WHO, 310 patients were diagnosed with leprosy (paucibacillary = 159; multibacillary = 151), of whom 263 were sampled for a skin biopsy and fingerstick blood, and 260 for a minimally-invasive nasal swab. In 74.5% of all skin biopsies and in 15.4% of all nasal swabs, M. leprae DNA was detected. In 63.1% of fingerstick blood samples, M. leprae specific antibodies were detected with the quantitative αPGL-I test. Results show a strong correlation of αPGL-I IgM levels in fingerstick blood and RLEP-qPCR positivity of nasal swabs, with the M. leprae bacterial load measured by RLEP-qPCR of skin biopsies. Patients with a high bacterial load (≥50,000 bacilli in a skin biopsy) can be identified with combination of counting lesions and the αPGL-I test. To our knowledge, this is the first study that compared αPGL-I IgM levels in fingerstick blood with the bacterial load determined by RLEP-qPCR in skin biopsies of leprosy patients. The demonstrated potential of minimally invasive sampling such as fingerstick blood samples to identify high bacterial load persons likely to be accountable for the ongoing transmission, merits further evaluation in follow-up studies.

Exploring clustering of leprosy in the Comoros and Madagascar: A geospatial analysis.

OBJECTIVES: To identify patterns of spatial clustering of leprosy. DESIGN: We performed a baseline survey for a trial on post-exposure prophylaxis for leprosy in Comoros and Madagascar. We screened 64 villages, door-to-door, and recorded results of screening, demographic data and geographic coordinates. To identify clusters, we fitted a purely spatial Poisson model using Kulldorff's spatial scan statistic. We used a regular Poisson model to assess the risk of contracting leprosy at the individual level as a function of distance to the nearest known leprosy patient. RESULTS: We identified 455 leprosy patients; 200 (44.0%) belonged to 2735 households included in a cluster. Thirty-eight percent of leprosy patients versus 10% of the total population live ≤25 m from another leprosy patient. Risk ratios for being diagnosed with leprosy were 7.3, 2.4, 1.8, 1.4 and 1.7, for those at the same household, at 1-<25 m, 25-<50 m, 50-<75 m and 75-<100 m as/from a leprosy patient, respectively, compared to those living at ≥100 m. CONCLUSIONS: We documented significant clustering of leprosy beyond household level, although 56% of cases were not part of a cluster. Control measures need to be extended beyond the household, and social networks should be further explored.

Protocol, rationale and design of PEOPLE (Post ExpOsure Prophylaxis for LEprosy in the Comoros and Madagascar): a cluster randomized trial on effectiveness of different modalities of implementation of post-exposure prophylaxis of leprosy contacts.

BACKGROUND: Leprosy is an ancient infectious disease with a global annual incidence that has plateaued above 200,000 new cases since over a decade. New strategies are required to overcome this stalemate. Post-exposure prophylaxis (PEP) with a single dose of Rifampicin (SDR) has conditionally been recommended by the World Health Organization (WHO), based on a randomized-controlled-trial in Bangladesh. More evidence is required. The Post ExpOsure Prophylaxis for Leprosy (PEOPLE) trial will assess effectiveness of different modalities of PEP on the Comoros and Madagascar. METHODS: PEOPLE is a cluster-randomized trial with villages selected on previous leprosy-incidence and randomly allocated to four arms. Four annual door-to-door surveys will be performed in all arms. All consenting permanent residents will be screened for leprosy. Leprosy patients will be treated according to international guidelines and eligible contacts will be provided with SDR-PEP. Arm-1 is the comparator in which no PEP will be provided. In arms 2, 3 and 4, SDR-PEP will be provided at double the regular dose (20 mg/kg) to eligible contacts aged two years and above. In arm 2 all household-members of incident leprosy patients are eligible. In arm 3 not only household-members but also neighbourhood contacts living within 100-m of an incident case are eligible. In arm 4 such neighbourhood contacts are only eligible if they test positive to anti-PGL-I, a serological marker. Incidence rate ratios calculated between the comparator arm 1 and each of the intervention arms will constitute the primary outcome. DISCUSSION: Different trials on PEP have yielded varying results. The pivotal COLEP trial in Bangladesh showed a 57% reduction in incidence over a two-year period post-intervention without any rebound in the following years. A study in a high-incidence setting in Indonesia showed no effect of PEP provided to close contacts but a major effect of PEP provided as a blanket measure to an entire island population. High background incidence could be the reason of the lack of effect of PEP provided to individual contacts. The PEOPLE trial will assess effectiveness of PEP in a high incidence setting and will compare three different approaches, to identify who benefits most from PEP. TRIAL REGISTRATION: Clinicaltrials.Gov. NCT03662022. Initial Protocol Version 1.2, 27-Aug-2018.

Clustering of leprosy beyond the household level in a highly endemic setting on the Comoros, an observational study.

BACKGROUND: The island of Anjouan (Comoros) is highly endemic for leprosy with an annual incidence of 5-10/10,000. In May/June, 2015 single-dose Rifampicin post-exposure prophylaxis (SDR-PEP) was administered to 269 close contacts of 70 leprosy-patients in four villages as a pilot programmatic intervention. Two years later we revisited the villages for follow-up investigations. The main aim of our study was to quantify spatial associations between reported leprosy cases before and after PEP implementation. A secondary aim was to assess the effect of this single round of SDR-PEP at the individual level. METHODS: We conducted door-to-door leprosy screening in all four villages in August/September, 2017. We screened all consenting individuals for leprosy and recorded geographic coordinates of their household. We also recorded whether they had received SDR-PEP and whether they had been diagnosed with leprosy, before or after the 2015 intervention. We fitted a Poisson model with leprosy as outcome and distance to the nearest pre-intervention case and SDR-PEP as predictors. RESULTS: During the survey we found 114 new cases among 5760 contacts screened (2.0% prevalence), in addition to the 39 cases detected in the two preceding years. We found statistically significant associations of incident leprosy with physical distance to index cases ranging from 2.4 (95% confidence interval (95% CI) 1.5-3.6) for household contacts to 1.8 (95% CI 1.3-2.5) for those living at 1-25 m, compared to individuals living at ≥75 m. The effect of SDR-PEP appeared protective but did not reach statistical significance due to the low numbers, with an incidence rate ratio (IRR) of 0.6 (95% CI 0.3-1.2) overall, and 0.5 (95% CI 0.2-1.3) when considering only household contacts. CONCLUSIONS: This pilot demonstrated an increased risk of leprosy in contacts beyond the household, therefore a wider circle should be considered for chemoprophylaxis. Baseline surveys and extended contact definitions are essential for improving SDR-PEP effectiveness.

[Linear tuberculoid leprosy along the lines of Blaschko: a very rare presentation]. / Lèpre tuberculoïde de disposition linéaire blaschkoïde: une présentation exceptionnelle.

BACKGROUND: Leprosy continues to be present in certain regions throughout the world, and the dermatologist plays a central role in its diagnosis. Herein we report a case of tuberculoid leprosy that is atypical in terms of its linear presentation which appears to follow the lines of Blaschko. PATIENTS AND METHODS: A patient from Mayotte was referred to the neurological department for suspected tuberculoid leprosy. He was presenting a deficiency of the ulnar nerve together with neuronal hypertrophy and cutaneous involvement. Dermatological examination revealed linear hypo-aesthetic hypopigmented lesions on the arm and forearm. The atypical clinical presentation also suggested to us pigmented mosaicism or post-inflammatory pigmentation. The biopsy showed granulomatous epithelial dermatitis with perinervous involvement. Imaging examinations confirmed the presence of neuronal hypertrophy. A diagnosis of linear tuberculoid leprosy was made. DISCUSSION: This case illustrates the need to bear in mind a diagnosis of leprosy in the event of hypopigmented lesions, even where they are linear and of Blaschkoid appearance. Several potential hypotheses may account for this particular topographical pattern.

[Delayed home screening of leprosy; experience of the screening team in Mayotte]. / Dépistage actif intra-domiciliaire différé de la lèpre : expérience de l'equipe de dépistage sur l'île de mayotte.

Mayotte, a French territory island located in the Indian Ocean near Madagascar, remains a leprosy endemic area. In 2006, leprosy was still a problem of public health with a prevalence of 3.94 per 10,000 inhabitants. There is practically no formal consensus about active screening (AS) on an index case. According to teams and their related staffs, the AS concerns intradomicilary contact individuals (IDC) restrictively or extended to extra-domicilary social and professional contacts. Date, number and frequency of these investigations depend on each team. Between 1997 and 2003, there was no AS planned in Mayotte, but all index case individuals have been encouraged to propose a screening to their relatives through specific campaign information and education. This procedure allowed to identify 10 new cases of leprosy infection among the IDC. Concurrently 12 IDC cases have been diagnosed by health workers. In 2003, we performed a postponed AS within IDC of every Mahorais case registered by passive detection between 1997 and 2003. 325 IDC have been examined and 15 new cases have been detected. All these new cases showed early leprosy features: 14 were paucibacillary forms, among which 9 cases with an isolated cutaneous lesion (7 had an infracentimetric lesion). One patient had multibacillary disease although he presented with an isolated skin lesion which developed within the 6 previous months. None presented with disability. Our results suggest that passive detection even reinforced by repeated individual information and education about leprosy is neither appropriate nor effective. The postponed AS seems to favour an increased self-esteem and a better involvement of the index patient in sanitary education together with the screening of his relatives. In the Mayotte background, the postponed AS has not been associated with a significant delay for diagnosis. Although WHO recommandations are to abandon immediate AS of IDC and to promote self-screening for leprosy our study suggests an intermediate position, namely delayed active screening for an enhanced effective detection.

[Combination of three cutaneous diseases in Mayotte]. / Une triple atteinte dermatologique a Mayotte.

This report describes the case of a young woman from Mayotte (Comoros Islands) who presented a combination of three cutaneous diseases, i.e. pityriasis versicolor, scabies, and multibacillary leprosy. Symptoms of leprosy were concealed by those of the other two diseases. After multidrug therapy for leprosy, the patient developed erythema nodosum leprosum that was successfully treated using pentoxifylline. Combination of cutaneous diseases can alter usual presentations and lead to misdiagnosis. It is important to take into account possible disease combination to establish proper diagnosis and prescribe effective treatment.

[Hansen's disease in the territorial collective of Mayotte (Indian Ocean); retrospective study from 1990-1998]. / La maladie de Hansen dans la collectivité territoriale de Mayotte (Océan Indien): etude rétrospective de 1990 à 1998.

Mayotte French island of the Comoro Islands in the Indian Ocean, is located in a leprosy endemic area including the other islands of the archipelago and Madagascar island. As the last Hansen's disease epidemiological study in the island have been reported in 1982, we achieved a new valuation by a retrospective study on the 1990-1998 period. Our investigation showed that the disease was still endemic with a prevalence of 32/100,000 population in 1998 and an high annual new case detection rate (14 to 31/100,000 population). The profile of the newly detected cases was the same that reported at the world level (prédominance of males, less than 45-years old adults and paucibacillary forms) with two exceptions: the high percentage of children below 15 years of age (28.2%) and of family cases (25.3%). Moreover, 12.6% of the new cases exhibited disabilities grade 2 at the time of the diagnosis. These features emphasize the need for an enhanced leprosy control in this island which has a well-developed medical assistance.