Implementation approaches for leprosy prevention with single-dose rifampicin: A support tool for decision making.

BACKGROUND: In the past 15 years, the decline in annually detected leprosy patients has stagnated. To reduce the transmission of Mycobacterium leprae, the World Health Organization recommends single-dose rifampicin (SDR) as post-exposure prophylaxis (PEP) for contacts of leprosy patients. Various approaches to administer SDR-PEP have been piloted. However, requirements and criteria to select the most suitable approach were missing. The aims of this study were to develop an evidence-informed decision tool to support leprosy programme managers in selecting an SDR-PEP implementation approach, and to assess its user-friendliness among stakeholders without SDR-PEP experience. METHODOLOGY: The development process comprised two phases. First, a draft tool was developed based on a literature review and semi-structured interviews with experts from various countries, organisations and institutes. This led to: an overview of existing SDR-PEP approaches and their characteristics; understanding the requirements and best circumstances for these approaches; and, identification of relevant criteria to select an approach. In the second phase the tool's usability and applicability was assessed, through interviews and a focus group discussion with intended, inexperienced users; leprosy programme managers and non-governmental organization (NGO) staff. PRINCIPAL FINDINGS: Five SDR-PEP implementation approaches were identified. The levels of endemicity and stigma, and the accessibility of an area were identified as most relevant criteria to select an approach. There was an information gap on cost-effectiveness, while successful implementation depends on availability of resources. Five basic requirements, irrespective of the approach, were identified: stakeholder support; availability of medication; compliant health system; trained health staff; and health education. Two added benefits of the tool were identified: its potential value for advocacy and for training. CONCLUSION: An evidence-informed SDR-PEP decision tool to support the selection of implementation approaches for leprosy prevention was developed. While the tool was evaluated by potential users, more research is needed to further improve the tool, especially health-economic studies, to ensure efficient and cost-effective implementation of SDR-PEP.

Implementation of genetic screening test to reduce the incidence of dapsone hypersensitivity syndrome among patients with leprosy in Papua, Indonesia: a study protocol.

INTRODUCTION: The mainstay of leprosy treatment is multidrug treatment (MDT), which contains rifampicin, dapsone and clofazimine. The occurrence of dapsone hypersensitivity syndrome (DHS), a sudden, potentially fatal and traumatic adverse reaction due to dapsone, may affect treatment adherence and may result in fatality if untreated. Before MDT administration, screening for HLA-B*13:01 in patients with leprosy can potentially reduce DHS risk. The study aims to assess the effectiveness of using a screening test for HLA-B*13:01 in reducing the incidence of DHS and to evaluate the feasibility of using the quantitative PCR-based screening tool as DHS predictors before dapsone administration using individual patient testing in a referral centralised-lab model. METHODS AND ANALYSIS: A total of 310 newly diagnosed patients with leprosy will be recruited from health centres in two highly endemic districts in Indonesia. Dried blood will be taken on filter paper as the specimen receptacle to collect DNA from the patients and transported at room temperature to the leprosy referral laboratory before MDT administration. Checking for HLA-B*13:01 from human DNA is performed using the Nala PGx 1301 V.1 kit. The results will be shared with the leprosy health workers on the site via phone call and courier. Patients with a positive test result will be treated with MDT without dapsone, and patients with a negative result will be treated with complete MDT. Physical examination (weight, height, skin, muscle and nerve function examination), complete blood tests (including renal function test) will be carried out at baseline. Follow-up will be performed at the fourth and eighth weeks to observe any development of adverse drug reactions. ETHICS AND DISSEMINATION: The ethical approval for the study was issued by the Ethical Committee of the National Institute of Health Research and Development, Ministry of Health, Indonesia. Written informed consent will be sought from all participants.

The long-term impact of the Leprosy Post-Exposure Prophylaxis (LPEP) program on leprosy incidence: A modelling study.

BACKGROUND: The Leprosy Post-Exposure Prophylaxis (LPEP) program explored the feasibility and impact of contact tracing and the provision of single dose rifampicin (SDR) to eligible contacts of newly diagnosed leprosy patients in Brazil, India, Indonesia, Myanmar, Nepal, Sri Lanka and Tanzania. As the impact of the programme is difficult to establish in the short term, we apply mathematical modelling to predict its long-term impact on the leprosy incidence. METHODOLOGY: The individual-based model SIMCOLEP was calibrated and validated to the historic leprosy incidence data in the study areas. For each area, we assessed two scenarios: 1) continuation of existing routine activities as in 2014; and 2) routine activities combined with LPEP starting in 2015. The number of contacts per index patient screened varied from 1 to 36 between areas. Projections were made until 2040. PRINCIPAL FINDINGS: In all areas, the LPEP program increased the number of detected cases in the first year(s) of the programme as compared to the routine programme, followed by a faster reduction afterwards with increasing benefit over time. LPEP could accelerate the reduction of the leprosy incidence by up to six years as compared to the routine programme. The impact of LPEP varied by area due to differences in the number of contacts per index patient included and differences in leprosy epidemiology and routine control programme. CONCLUSIONS: The LPEP program contributes significantly to the reduction of the leprosy incidence and could potentially accelerate the interruption of transmission. It would be advisable to include contact tracing/screening and SDR in routine leprosy programmes.

Leprosy post-exposure prophylaxis with single-dose rifampicin (LPEP): an international feasibility programme.

BACKGROUND: Innovative approaches are required for leprosy control to reduce cases and curb transmission of Mycobacterium leprae. Early case detection, contact screening, and chemoprophylaxis are the most promising tools. We aimed to generate evidence on the feasibility of integrating contact tracing and administration of single-dose rifampicin (SDR) into routine leprosy control activities. METHODS: The leprosy post-exposure prophylaxis (LPEP) programme was an international, multicentre feasibility study implemented within the leprosy control programmes of Brazil, India, Indonesia, Myanmar, Nepal, Sri Lanka, and Tanzania. LPEP explored the feasibility of combining three key interventions: systematically tracing contacts of individuals newly diagnosed with leprosy; screening the traced contacts for leprosy; and administering SDR to eligible contacts. Outcomes were assessed in terms of number of contacts traced, screened, and SDR administration rates. FINDINGS: Between Jan 1, 2015, and Aug 1, 2019, LPEP enrolled 9170 index patients and listed 179 769 contacts, of whom 174 782 (97·2%) were successfully traced and screened. Of those screened, 22 854 (13·1%) were excluded from SDR mainly because of health reasons and age. Among those excluded, 810 were confirmed as new patients (46 per 10 000 contacts screened). Among the eligible screened contacts, 1182 (0·7%) refused prophylactic treatment with SDR. Overall, SDR was administered to 151 928 (86·9%) screened contacts. No serious adverse events were reported. INTERPRETATION: Post-exposure prophylaxis with SDR is safe; can be integrated into different leprosy control programmes with minimal additional efforts once contact tracing has been established; and is generally well accepted by index patients, their contacts, and health-care workers. The programme has also invigorated local leprosy control through the availability of a prophylactic intervention; therefore, we recommend rolling out SDR in all settings where contact tracing and screening have been established. FUNDING: Novartis Foundation.

Leprosy post-exposure prophylaxis with single-dose rifampicin (LPEP): an international feasibility programme

Background: Innovative approaches are required for leprosy control to reduce cases and curb transmission of Mycobacterium leprae. Early case detection, contact screening, and chemoprophylaxis are the most promising tools. We aimed to generate evidence on the feasibility of integrating contact tracing and administration of single-dose rifampicin (SDR) into routine leprosy control activities. Methods The leprosy post-exposure prophylaxis (LPEP) programme was an international, multicentre feasibility study implemented within the leprosy control programmes of Brazil, India, Indonesia, Myanmar, Nepal, Sri Lanka, and Tanzania. LPEP explored the feasibility of combining three key interventions: systematically tracing contacts of individuals newly diagnosed with leprosy; screening the traced contacts for leprosy; and administering SDR to eligible contacts. Outcomes were assessed in terms of number of contacts traced, screened, and SDR administration rates. Findings Between Jan 1, 2015, and Aug 1, 2019, LPEP enrolled 9170 index patients and listed 179 769 contacts, of whom 174782 (97·2%) were successfully traced and screened. Of those screened, 22 854 (13·1%) were excluded from SDR mainly because of health reasons and age. Among those excluded, 810 were confirmed as new patients (46 per 10 000 contacts screened). Among the eligible screened contacts, 1182 (0·7%) refused prophylactic treatment with SDR. Overall, SDR was administered to 151 928 (86·9%) screened contacts. No serious adverse events were reported. Interpretation Post-exposure prophylaxis with SDR is safe; can be integrated into different leprosy control programmes with minimal additional efforts once contact tracing has been established; and is generally well accepted by index patients, their contacts, and health-care workers. The programme has also invigorated local leprosy control through the availability of a prophylactic intervention; therefore, we recommend rolling out SDR in all settings where contact tracing and screening have been established(AU).

The long-term impact of the leprosy post-exposure prophylaxis (LPEP) program on leprosy incidence: a modelling study

The Leprosy Post-Exposure Prophylaxis (LPEP) program explored the feasibility and impact of contact tracing and the provision of SDR to eligible contacts of newly diagnosed leprosy patients in states or districts of Brazil, India, Indonesia, Myanmar, Nepal, Sri Lanka and Tanzania. This study investigated the long-term impact of the LPEP program on the leprosy new case detection rate (NCDR). Our results show that LPEP could reduce the NCDR beyond the impact of the routine leprosy control programme and that many new cases could be prevented. The benefit of LPEP increases gradually over time. LPEP could accelerate the time of reaching predicted NCDR levels of 2040 under routine program by up to six years. Furthermore, we highlighted how the impact varies between countries due to differences in the number of contacts per index patient screened and differences in leprosy epidemiology and national control programme. Generally, including both household contacts and neighbours (> 20 contacts per index patient) would yield the highest impact.

The State of Affairs in Post-Exposure Leprosy Prevention: A Descriptive Meta-Analysis on Immuno- and Chemo-Prophylaxis.

OBJECTIVE: Annually, over 200,000 people are diagnosed with leprosy, also called Hansen's disease. This number has been relatively stable over the past years. Progress has been made in the fields of chemoprophylaxis and immunoprophylaxis to prevent leprosy, with a primary focus on close contacts of patients. In this descriptive meta-analysis, we summarize the evidence and identify knowledge gaps regarding post-exposure prophylaxis against leprosy. METHODS: A systematic literature search according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was conducted by searching the medical scientific databases Cochrane, Embase, Pubmed/MEDLINE, Research Gate, Scopus and Web of Science on Jan. 22, 2020, using a combination of synonyms for index terms in four languages: "leprosy" and "population" or "contacts" and "prevention" or "prophylaxis." Subsequently, Infolep.org and Google Scholar were searched and the "snowball method" was used to retrieve other potentially relevant literature. The found articles were screened for eligibility using predetermined inclusion and exclusion criteria. RESULTS: After deduplication, 1,515 articles were screened, and 125 articles were included in this descriptive meta-analysis. Immunoprophylaxis by bacillus Calmette-Guérin (BCG) vaccination is known to provide protection against leprosy. The protection it offers is higher in household contacts of leprosy patients compared with the general population and is seen to decline over time. Contact follow-up screening is important in the first period after BCG administration, as a substantial number of new leprosy patients presents three months post-vaccination. Evidence for the benefit of re-vaccination is conflicting. The World Health Organization (WHO) included BCG in its Guidelines for the Diagnosis, Treatment and Prevention of Leprosy by stating that BCG at birth should be maintained in at least all leprosy high-burden regions. Literature shows that several vaccination interventions with other immunoprophylactic agents demonstrate similar or slightly less efficacy in leprosy risk reduction compared with BCG. However, most of these studies do not exclusively focus on post-exposure prophylaxis. Two vaccines are considered future candidates for leprosy prophylaxis: Mycobacterium indicus pranii (MiP) and LepVax. For chemoprophylaxis, trials were performed with dapsone/acedapsone, rifampicin, and ROM, a combination of rifampicin, ofloxacin, and minocycline. Single-dose rifampicin is favored as post-exposure prophylaxis, abbreviated as SDR-PEP. It demonstrated a protective effect of 57% in the first two years after administration to contacts of leprosy patients. It is inexpensive, and adverse events are rare. The risk of SDR-PEP inducing rifampicin resistance is considered negligible, but continuous monitoring in accordance with WHO policies should be encouraged. The integration of contact screening and SDR-PEP administration into different leprosy control programs was found to be feasible and well accepted. Since 2018, SDR-PEP is included in the WHO Guidelines for the Diagnosis, Treatment and Prevention of Leprosy. CONCLUSION: Progress has been made in the areas of chemoprophylaxis and immunoprophylaxis to prevent leprosy in contacts of patients. Investing in vaccine studies, like LepVax and MiP, and increasing harmonization between tuberculosis (TB) and leprosy research groups is important. SDR-PEP is promising as a chemoprophylactic agent, and further implementation should be promoted. More chemoprophylaxis research is needed on: enhanced medication regimens; interventions in varying (epidemiological) settings, including focal mass drug administration (fMDA); specific approaches per contact type; combinations with screening variations and field-friendly rapid tests, if available in the future; community and health staff education; ongoing antibiotic resistance surveillance; and administering chemoprophylaxis with SDR-PEP prior to BCG administration. Additionally, both leprosy prophylactic drug registration nationally and prophylactic drug availability globally at low or no cost are important for the implementation and further upscaling of preventive measures against leprosy, such as SDR-PEP and new vaccines.

Prolaxis post-exposición para lepra con dosis única de rifampicina: manual para su implementación / Post-exposure prolaxis for leprosy with a single dose of rifampicin: a manual for its implementation

Objetivo: La profilaxis post-exposición de la lepra con dosis única de rifampicina (SDR-PEP) ha demostrado ser efectiva y aplicable y está recomendada por la OMS desde 2018. Esta caja de herramientas SDR-PEP se desarrolló a través de la experiencia de la profilaxis lepra post-eliminación (LPEP). Se ha diseñado para facilitar y estandarizar la implementación del seguimiento de contactos y la administración SDR-PEP en regiones y países que iniciaron la intervención. Resultados: Se desarrollaron cuatro instrumentos, incorporando la evidencia existente actual para SDR-PEP y los métodos y enseñanzas del proyecto LPEP en ocho países. (1) El conjunto de diapositivas Powerpoint política/apoyo que ayudarán a los programadores sobre la evidencia, practicabilidad y recursos necesarios para SDR-PEP, (2) La colección de diapositivas PowerPoint sobre formación e implementación en el campo para formar al personal implicado en el seguimiento de contactos y PEP con SDR, (3) manual genérico de campo SDR-PEP que puede ser usado para formar un protocolo específico de campo para el seguimiento de contactos y SDR-PEP como referencia para el personal directamente implicado. Finalmente, (4) el manual director SDR-PEP, que resume los distintos componentes de la caja de herramientas y contiene las instrucciones para su uso. Conclusión: En respuesta al interés manifestado por varios países de implementar el seguimiento de contactos de lepra con PEP con SDR, con las recomendaciones OMS sobre SDR-PEP, esta caja de herramientas basada en la evidencia concreta pero flexible, ha sido diseñada para servir a los directores de programas nacionales de lepra con un medio práctico para trasladar los planteamientos a la práctica. Está disponible gratuitamente en la página de Infolep y actualizada constantemente: https://www.leprosy-information.org/keytopic/leprosy-post-exposure-prophylaxis-lpep-programme(AU).

Objective: Leprosy post-exposure prophylaxis with single-dose rifampicin (SDRPEP) has proven effective and feasible, and is recommended by WHO since 2018. This SDR-PEP toolkit was developed through the experience of the leprosy post-exposure prophylaxis (LPEP) programme. It has been designed to facilitate and standardise the implementation of contact tracing and SDR-PEP administration in regions and countries that start the intervention. Results: Four tools were developed, incorporating the current evidence for SDRPEP and the methods and learnings from the LPEP project in eight countries. (1) the SDR-PEP policy/advocacy PowerPoint slide deck which will help to inform policy makers about the evidence, practicalities and resources needed for SDR-PEP, (2) the SDR-PEP field implementation training PowerPoint slide deck to be used to train front line staff to implement contact tracing and PEP with SDR, (3) the SDR-PEP generic field guide which can be used as a basis to create a location specific field protocol for contact tracing and SDR-PEP serving as a reference for frontline field staff. Finally, (4) the SDR-PEP toolkit guide, summarising the different components of the toolkit and providing instructions on its optimal use. Conclusion: In response to interest expressed by countries to implement contact tracing and leprosy PEP with SDR in the light of the WHO recommendation of SDRPEP, this evidence-based, concrete yet flexible toolkit has been designed to serve national leprosy programme managers and support them with the practical means to translate policy into practice. The toolkit is freely accessible on the Infolep homepages and updated as required: https://www.leprosy-information.org/keytopic/leprosy-postexposure-prophylaxis-lpep-programme(AU).

The frequency of drug resistance mutations in Mycobacterium leprae isolates in untreated and relapsed leprosy patients from Myanmar, Indonesia and the Philippines.

INTRODUCTION: The magnitude of drug resistance in Mycobacterium leprae to dapsone, rifampicin, and ofloxacin was studied in three Southeast Asian countries with a high prevalence of leprosy. METHODS: M. leprae from the skin of leprosy patients was collected in North Maluku and North Sulawesi in Indonesia, Yangon in Myanmar, and Cebu in the Philippines. Mutations in the drug resistance determining regions in the folP1, rpoB, and gyrA genes, which have been proven to confer resistance, were analysed. In addition, samples from 51 newly diagnosed cases and 13 patients with leprosy relapse in Cebu were submitted for susceptibility testing in the mouse footpad. RESULTS: Of 252 isolates obtained from new cases, 3% were dapsone resistant and 2% were rifampicin resistant. In samples taken from patients with relapsed leprosy (n = 53), significantly more resistance mutations were detected: 15% had dapsone resistance mutations, and 8% had rifampicin resistance mutations. Two patients with relapsed leprosy had mutations for both dapsone and rifampicin resistance. No mutations conferring quinolone resistance were detected. No mutations were detected in the folP1 gene of M. leprae isolates with a low degree of resistance to dapsone. DISCUSSION: Detection of drug-resistant cases by mutation detection in the drug resistance determining region of the genome is a practical method for monitoring resistance. A comparison of the results obtained in this study with previous data obtained prior to the use of multidrug therapy (MDT), does not indicate clearly whether the magnitude of drug resistance has changed. Larger studies of resistance mutations in M. leprae isolated from patients with relapsed leprosy are needed to confirm our results. CONCLUSION: We recommend monitoring the magnitude of drug resistance globally, by testing M. leprae DNA from relapse cases and a representative sample of new cases.

Genotypic analysis of Mycobacterium leprae isolates from Japan and other Asian countries reveals a global transmission pattern of leprosy.

The genotype of single-nucleotide polymorphism type 3, CTC, at positions 14676, 164275, and 2935685, along with four copies of 6 bp repeats in the rpoT gene, was predominant for isolates originating in the Japanese mainland. Type 1, CGA, type 2, CTA, and type 3 were detected from Korea, Indonesia, and Myanmar. No isolates with four copies of 6 bp were detected from Myanmar, Okinawa, and Japanese Brazilian patients. Type 4, TTC, with three copies of 6 bp, was detected only from Japanese Brazilians. The results indicate that infection occurred in Brazil and the disease developed later in Japan.

Diversity of potential short tandem repeats in Mycobacterium leprae and application for molecular typing.

A recent advance in molecular typing for tracing the transmission of leprosy is the discovery of short tandem repeats (STRs) in Mycobacterium leprae. To substantiate polymorphic loci from STR as promising candidates for molecular typing tools in leprosy epidemiology, 44 STR loci including 33 microsatellites and 11 minisatellites were investigated among 27 laboratory strains by sequencing PCR products. Not all STRs were necessarily polymorphic. Thirty-two out of the 44 loci were polymorphic. Nine polymorphic loci were suitable for identifying genotypes according to the discriminatory capacity, stability, and reproducibility. All the strains were classified into independent genotypes by the selected nine loci. Three multi-case households were subjected to molecular typing. M. leprae obtained from household cases showed identical copy numbers by TTC triplet alone, but the isolates from one family contact case were divided into different genotypes by adding eight other polymorphic loci. The combination of information from multiple loci allows increasing levels of discrimination and it is likely that the generation and documentation of data will result in the choice of a potential molecular typing tool for leprosy epidemiology.

Diversity of potential short tandem repeats in Mycobacterium leprae and application for molecular typing

A recent advance in molecular typing for tracing the transmission of leprosy is the discovery of short tandem repeats (STRs) in Mycobacterium leprae. To substantiate polymorphic loci from STR as promising candidates for molecular typing tools in leprosy epidemiology, 44 STR loci including 33 microsatellites and 11 minisatellites were investigated among 27 laboratory strains by sequencing PCR products. Not all STRs were necessarily polymorphic. Thirty-two out of the 44 loci were polymorphic. Nine polymorphic loci were suitable for identifying genotypes according to the discriminatory capacity, stability, and reproducibility. All the strains were classified into independent genotypes by the selected nine loci. Three multi-case households were subjected to molecular typing. M. leprae obtained from household cases showed identical copy numbers by TTC triplet alone, but the isolates from one family contact case were divided into different genotypes by adding eight other polymorphic loci. The combination of information from multiple loci allows increasing levels of discrimination and it is likely that the generation and documentation of data will result in the choice of a potential molecular typing tool for leprosy epidemiology.

Genotyping of Mycobacterium leprae on the basis of the polymorphism of TTC repeats for analysis of leprosy transmission.

The polymorphism of TTC repeats in Mycobacterium leprae was examined using the bacilli obtained from residents in villages at North Maluku where M. leprae infections are highly endemic (as well as from patients at North Sulawesi of Indonesia) to elucidate the possible mode of leprosy transmission. TTC genotypes are stable for several generations of passages in nude mice footpads and, hence, are feasible for the genotyping of isolates and epidemiological analysis of leprosy transmission. It was found that bacilli with different TTC genotypes were distributed among residents at the same dwelling in villages in which leprosy is endemic and that some household contacts harbored bacilli with a different genotype from that harbored by the patient. Investigations of a father-and-son pair of patients indicated that infections of bacilli with 10 and 18 copies, respectively, had occurred. Genotypes of TTC repeats were found to differ between a son under treatment and two brothers. These results reveal the possibility that in addition to exposure via the presence of a leprosy patient with a multibacillary infection who was living with family members, there might have been some infectious sources to which the residents had been commonly exposed outside the dwellings. A limited discriminative capacity of the TTC polymorphism in the epidemiological analysis implies the need of searching other useful polymorphic loci for detailed subdivision of clinical isolates.