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Jan Hendrik Richardus - One of the best experts on this subject based on the ideXlab platform.
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Leprosy post exposure prophylaxis with single dose rifampicin lpep an international feasibility programme
The Lancet Global Health, 2021Co-Authors: Jan Hendrik Richardus, Anuj Tiwari, Tanja Barthjaeggi, Mohammad Arif, Nand Lal Banstola, Rabindra Baskota, David D Blaney, David J Blok, Marc BonenbergerAbstract:Summary 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.
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Mycobacterium leprae transmission characteristics during the declining stages of Leprosy incidence: A systematic review.
'Public Library of Science (PLoS)', 2021Co-Authors: Thomas Hambridge, Paul Saunderson, Shri Lak Nanjan Chandran, Annemieke Geluk, Jan Hendrik RichardusAbstract:BackgroundLeprosy is an infectious disease caused by Mycobacterium leprae. As incidence begins to decline, the characteristics of new cases shifts away from those observed in highly endemic areas, revealing potentially important insights into possible ongoing sources of transmission. We aimed to investigate whether transmission is driven mainly by undiagnosed and untreated new Leprosy cases in the community, or by incompletely treated or relapsing cases.Methodology/principal findingsA literature search of major electronic databases was conducted in January, 2020 with 134 articles retained out of a total 4318 records identified (PROSPERO ID: CRD42020178923). We presented quantitative data from Leprosy case records with supporting evidence describing the decline in incidence across several contexts. BCG vaccination, active case finding, adherence to multidrug therapy and continued surveillance following treatment were the main strategies shared by countries who achieved a substantial reduction in incidence. From 3950 Leprosy case records collected across 22 low endemic countries, 48.3% were suspected to be imported, originating from transmission outside of the country. Most cases were multibacillary (64.4%) and regularly confirmed through skin biopsy, with 122 cases of suspected relapse from previous Leprosy treatment. Family history was reported in 18.7% of cases, while other suspected sources included travel to high endemic areas and direct contact with armadillos. None of the countries included in the analysis reported a distinct increase in Leprosy incidence in recent years.Conclusions/significanceTogether with socioeconomic improvement over time, several successful Leprosy Control programmes have been implemented in recent decades that led to a substantial decline in incidence. Most cases described in these contexts were multibacillary and numerous cases of suspected relapse were reported. Despite these observations, there was no indication that these cases led to a rise in new secondary cases, suggesting that they do not represent a large ongoing source of human-to-human transmission
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Leprosy post-exposure prophylaxis in the Indian health system: A cost-effectiveness analysis.
'Public Library of Science (PLoS)', 2020Co-Authors: Anuj Tiwari, Mohammad Arif, David J Blok, Jan Hendrik RichardusAbstract:India has the highest burden of Leprosy in the world. Following a recent WHO guideline, the Indian National Leprosy Programme is introducing post-exposure prophylaxis with single-dose rifampicin (SDR-PEP) in all high-endemic districts of the country. The aim of this study is to estimate the long-term cost-effectiveness of SDR-PEP in different Leprosy disability burden situations. We used a stochastic individual-based model (SIMCOLEP) to simulate the Leprosy new case detection rate trend and the impact of implementing contact screening and SDR-PEP from 2016 to 2040 (25 years) in the Union Territory of Dadra Nagar Haveli (DNH) in India. Effects of the intervention were expressed as disability adjusted life years (DALY) averted under three assumption of disability prevention: 1) all grade 1 disability (G1D) cases prevented; 2) G1D cases prevented in PB cases only; 3) no disability prevented. Costs were US$ 2.9 per contact. Costs and effects were discounted at 3%. The incremental cost per DALY averted by SDR-PEP was US$ 210, US$ 447, and US$ 5,673 in the 25th year under assumption 1, 2, and 3, respectively. If prevention of G1D was assumed, the probability of cost-effectiveness was 1.0 at the threshold of US$ 2,000, which is equivalent to the GDP per capita of India. The probability of cost-effectiveness was 0.6, if no disability prevention was assumed. The cost per new Leprosy case averted was US$ 2,873. Contact listing, screening and the provision of SDR-PEP is a cost-effective strategy in Leprosy Control in both the short (5 years) and long term (25 years). The cost-effectiveness depends on the extent to which disability can be prevented. As the intervention becomes increasingly cost-effective in the long term, we recommend a long-term commitment for its implementation
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introducing Leprosy post exposure prophylaxis into the health systems of india nepal and indonesia a case study
BMC Health Services Research, 2017Co-Authors: Anuj Tiwari, Mohammad Arif, L. Mieras, K. Dhakal, S. Dandel, Jan Hendrik RichardusAbstract:Leprosy has a wide range of clinical and socio-economic consequences. India, Indonesia and Nepal contribute significantly to the global Leprosy burden. After integration, the health systems are pivotal in Leprosy service delivery. The Leprosy Post Exposure Prophylaxis (LPEP) program is ongoing to investigate the feasibility of providing single dose rifampicin (SDR) as post-exposure prophylaxis (PEP) to the contacts of Leprosy cases in various health systems. We aim to compare national Leprosy Control programs, and adapted LPEP strategies in India, Nepal and Indonesia. The purpose is to establish a baseline of the health system’s situation and document the subsequent adjustment of LPEP, which will provide the context for interpreting the LPEP results in future. The study followed the multiple-case study design with single units of analysis. The data collection methods were direct observation, in-depth interviews and desk review. The study was divided into two phases, i.e. review of national Leprosy programs and description of the LPEP program. The comparative analysis was performed using the WHO health system frameworks (2007). In all countries Leprosy services including contact tracing is integrated into the health systems. The LPEP program is fully integrated into the established national Leprosy programs, with SDR and increased documentation, which need major additions to standard procedures. PEP administration was widely perceived as well manageable, but the additional LPEP data collection was reported to increase workload in the first year. The findings of our study led to the recommendation that field-based Leprosy research programs should keep health systems in focus. The national Leprosy programs are diverse in terms of organizational hierarchy, human resource quantity and capacity. We conclude that PEP can be integrated into different health systems without major structural and personal changes, but provisions are necessary for the additional monitoring requirements.
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protecting people against Leprosy chemoprophylaxis and immunoprophylaxis
Clinics in Dermatology, 2015Co-Authors: Jan Hendrik Richardus, Linda OskamAbstract:Elimination of Leprosy cannot be achieved by multidrug therapy alone, and new tools are needed to prevent Leprosy. A randomized Controlled trial with chemoprophylaxis for contacts of Leprosy patients using a single dose of rifampicin (SDR) has shown an overall protective effect of approximately 60%, effective in the first 2 years after the intervention. When a contact who previously received bacillus Calmette-Guerin (BCG) vaccination also receives SDR, the protective effect is additive, approximating 80%. Vaccine trials have been conducted with BCG, often in combination with Mycobacterium leprae or related Mycobacterium vaccines as immunoprophylaxis for contacts of Leprosy patients, with BCG giving the best results. Meta-analysis shows that the protective effect of BCG vaccination is larger in observational studies than in trials, 60% versus 41%, and is higher among contacts of Leprosy patients than among the general population, 68% versus 53%. We believe that a future Leprosy Control strategy should include contact management, consisting of a contact survey, at which time preventive interventions could be added, such as chemoprophylaxis and immunoprophylaxis. Modeling studies have shown that both interventions will lower the incidence of Leprosy in the population. Implementation studies of such contact-based strategy are now called for.
P R Klatser - One of the best experts on this subject based on the ideXlab platform.
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the relation between seroprevalence of antibodies against phenolic glycolipid i among school children and Leprosy endemicity in brazil
Revista Da Sociedade Brasileira De Medicina Tropical, 2008Co-Authors: Samira Buhrersekula, Linda Oskam, William R Faber, Stella M Van Beers, Rita Lecco, Elisabete Santos Madeira, Marco Antonio Lopes Dutra, Magali Chaves Luis, P R KlatserAbstract:Leprosy Control programs would benefit expressively from an easy method to estimate disease prevalence and to assess the effect of Leprosy Control measures on disease prevalence. Determination of the seroprevalence of antibodies to PGL-I through school children surveys might be a useful indicator of Leprosy prevalence at the district level. To investigate whether seropositivity rates could be related to Leprosy detection rates and whether seropositivity could be used as a proximal indicator to predict the Leprosy incidence in other areas, 7,073 school children in three different Leprosy-endemic states in Brazil were tested. The results show a widely varying distribution of seropositivity in the communities independent of the number of Leprosy cases detected. Seroprevalence was significantly lower at private schools. No differences in the patterns of seropositivity between ELISA and dipstick were observed. No correlation between Leprosy detection rate and seropositivity rates could be established.
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the ml flow test as a point of care test for Leprosy Control programmes potential effects on classification of Leprosy patients
Leprosy Review, 2007Co-Authors: Samira Buhrersekula, P R Klatser, Jan Visschedijk, Maria Aparecida De Faria Grossi, Krishna P Dhakal, Abdullahi U Namadi, Linda OskamAbstract:OBJECTIVE: To evaluate the use of the ML Flow test as an additional, serological, tool for the classification of new Leprosy patients. DESIGN: In Brazil, Nepal and Nigeria, 2632 Leprosy patients were classified by three METHODS: : (1) as multibacillary (MB) or paucibacillary (PB) according to the number of skin lesions (WHO classification), (2) by slit skin smear examination, and (3) by serology using the ML Flow test detecting IgM antibodies to Mycobacterium leprae-specific phenolic glycolipid-I. RESULTS: The proportion of MB Leprosy patients was 39.5, 35.6 and 19.4% in Brazil, Nepal and Nigeria, respectively. The highest seropositivity in patients was observed in Nigeria (62.9%), followed by Brazil (50.8%) and Nepal (35.6%). ML Flow test results and smears were negative in 69.1 and 82.7% of PB patients, while smears were positive in 58.6% of MB patients in Brazil and 28.3% in Nepal. In MB patients, both smears and ML Flow tests were negative in 15.6% in Brazil and 38.3%, in Nepal. Testing all PB patients with the ML Flow test to prevent under-treatment would increase the MB group by 18, 11 and 46.2% for Brazil, Nepal and Nigeria, respectively. Using the ML Flow test as the sole criterion for classification would result in an increase of 11.3 and 43.5% of patients requiring treatment for MB Leprosy in Brazil and Nigeria, respectively, and a decrease of 3.7% for Nepal. CONCLUSIONS: The ML Flow test could be used to strengthen classification, reduce the risk of under-treatment and minimize the need for slit skin smears.
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simple and fast lateral flow test for classification of Leprosy patients and identification of contacts with high risk of developing Leprosy
Journal of Clinical Microbiology, 2003Co-Authors: Samira Buhrersekula, Henk L Smits, George C Gussenhoven, J Van Leeuwen, S Amador, T Fujiwara, P R Klatser, Linda OskamAbstract:The interruption of Leprosy transmission is one of the main challenges for Leprosy Control programs since no consistent evidence exists that transmission has been reduced after the introduction of multidrug therapy. Sources of infection are primarily people with high loads of bacteria with or without clinical signs of Leprosy. The availability of a simple test system for the detection of antibodies to phenolic glycolipid-I (PGL-I) of Mycobacterium leprae to identify these individuals may be important in the prevention of transmission. We have developed a lateral flow assay, the ML Flow test, for the detection of antibodies to PGL-I which takes only 10 min to perform. An agreement of 91% was observed between enzyme-linked immunosorbent assay and our test; the agreement beyond chance (kappa value) was 0.77. We evaluated the use of whole blood by comparing 539 blood and serum samples from an area of high endemicity. The observed agreement was 85.9% (kappa = 0.70). Storage of the lateral flow test and the running buffer at 28°C for up to 1 year did not influence the results of the assay. The sensitivity of the ML Flow test in correctly classifying MB patients was 97.4%. The specificity of the ML Flow test, based on the results of the Control group, was 90.2%. The ML Flow test is a fast and easy-to-perform method for the detection of immunoglobulin M antibodies to PGL-I of M. leprae. It does not require any special equipment, and the highly stable reagents make the test robust and suitable for use in tropical countries.
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patient contact is the major determinant in incident Leprosy implications for future Control
International Journal of Leprosy and Other Mycobacterial Diseases, 1999Co-Authors: S Van Beers, Mochammad Hatta, P R KlatserAbstract:Notwithstanding the elimination efforts, Leprosy Control programs face the problem of many Leprosy patients remaining undetected. Leprosy Control focuses on early diagnosis through screening of household contacts, although this high-risk group generates only a small proportion of all incident cases. For the remaining incident cases, Leprosy Control programs have to rely on self-reporting of patients. We explored the extent to which other contact groups contribute to incident Leprosy. We examined retrospectively incident Leprosy over 25 years in a high-endemic village of 2283 inhabitants in Sulawesi, Indonesia, by systematically reviewing data obtained from the local program and actively gathering data through interviews and a house-to-house survey. We investigated the contact status in the past of every incident case. In addition to household contact, we distinguished neighbor and social contacts. Of the 101 incident cases over a 25-year period, 79 (78%) could be associated to contact with another Leprosy patient. Twenty-eight (28%) of these 101 cases were identified as household contacts, 36 (36%) as neighbors, and the remaining 15 (15%) as social contacts. Three patients had not had a traceable previous contact with another Leprosy patient, and no information could be gathered from 19 patients. The median span of time from the registration of the primary case to that of the secondary case was 3 years; 95% of the secondary cases were detected within 6 years after the primary case. The estimated risk for Leprosy was about nine times higher in households of patients and four times higher in direct neighboring houses of patients compared to households that had had no such contact with patients. The highest risk of Leprosy was associated with households of multibacillary patients. The risk of Leprosy for households of paucibacillary patients was similar to the risk of Leprosy for direct neighboring houses of multibacillary patients, indicating that both the type of Leprosy of the primary case and the distance to the primary case are important contributing factors for the risk of Leprosy. Contact with a Leprosy patient is the major determinant in incident Leprosy; the type of contact is not limited to household relationships but also includes neighbor and social relationships. This finding can be translated into a valuable and sustainable tool for Leprosy Control programs and elimination campaigns by focusing case detection and health promotion activities not only on household contacts but also on at least the neighbors of Leprosy cases.
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A SIMPLE DIPSTICK ASSAY FOR THE DETECTION OF ANTIBODIES TO PHENOLIC GLYCOLIPID-I OF MYCOBACTERIUM LEPRAE
The American journal of tropical medicine and hygiene, 1998Co-Authors: S S Bührer, Henk L Smits, George C Gussenhoven, C. W. Van Ingen, P R KlatserAbstract:Among the many reported applications of the detection of antibodies to phenolic glycolipid-I (PGL-I) of Mycobacterium leprae, in particular, the use of seroprevalence as an indicator of the magnitude of the Leprosy problem may turn out to be very useful in Leprosy Control programs. An operational function of serology within the Leprosy Control services requires a simple test system. We have developed a simple dipstick assay for the detection of antibodies to PGL-I and compared its performance with that of an ELISA. A high degree of agreement (97.2%) was observed between the ELISA and the dipstick assay when tested on 435 sera; the agreement beyond chance (Kappa value) was 0.92. No significant difference was found between the dipstick assay and the ELISA when seropositivity rates obtained in groups of Leprosy patients, household contacts, and Controls were compared. The interpretation of the dipstick results as positive or negative was unequivocal, as illustrated by the high agreement between different persons reading the test (Kappa values > 0.88). Storage of the only reagents required, the dipsticks and the stabilized detection reagent, up to three weeks under tropical conditions of high temperatures, high humidity, and exposure to light, did not influence the results of the assay. The dipstick assay described here is an easy-to-perform method for the detection of IgM antibodies to PGL-I of M. leprae; it does not require any special equipment and the highly stable reagents make the test robust and suitable for use in tropical countries. An internal Control validates the performance of the assay. This dipstick assay may be the method of choice for epidemiologic mapping of Leprosy.
Linda Oskam - One of the best experts on this subject based on the ideXlab platform.
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protecting people against Leprosy chemoprophylaxis and immunoprophylaxis
Clinics in Dermatology, 2015Co-Authors: Jan Hendrik Richardus, Linda OskamAbstract:Elimination of Leprosy cannot be achieved by multidrug therapy alone, and new tools are needed to prevent Leprosy. A randomized Controlled trial with chemoprophylaxis for contacts of Leprosy patients using a single dose of rifampicin (SDR) has shown an overall protective effect of approximately 60%, effective in the first 2 years after the intervention. When a contact who previously received bacillus Calmette-Guerin (BCG) vaccination also receives SDR, the protective effect is additive, approximating 80%. Vaccine trials have been conducted with BCG, often in combination with Mycobacterium leprae or related Mycobacterium vaccines as immunoprophylaxis for contacts of Leprosy patients, with BCG giving the best results. Meta-analysis shows that the protective effect of BCG vaccination is larger in observational studies than in trials, 60% versus 41%, and is higher among contacts of Leprosy patients than among the general population, 68% versus 53%. We believe that a future Leprosy Control strategy should include contact management, consisting of a contact survey, at which time preventive interventions could be added, such as chemoprophylaxis and immunoprophylaxis. Modeling studies have shown that both interventions will lower the incidence of Leprosy in the population. Implementation studies of such contact-based strategy are now called for.
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the relation between seroprevalence of antibodies against phenolic glycolipid i among school children and Leprosy endemicity in brazil
Revista Da Sociedade Brasileira De Medicina Tropical, 2008Co-Authors: Samira Buhrersekula, Linda Oskam, William R Faber, Stella M Van Beers, Rita Lecco, Elisabete Santos Madeira, Marco Antonio Lopes Dutra, Magali Chaves Luis, P R KlatserAbstract:Leprosy Control programs would benefit expressively from an easy method to estimate disease prevalence and to assess the effect of Leprosy Control measures on disease prevalence. Determination of the seroprevalence of antibodies to PGL-I through school children surveys might be a useful indicator of Leprosy prevalence at the district level. To investigate whether seropositivity rates could be related to Leprosy detection rates and whether seropositivity could be used as a proximal indicator to predict the Leprosy incidence in other areas, 7,073 school children in three different Leprosy-endemic states in Brazil were tested. The results show a widely varying distribution of seropositivity in the communities independent of the number of Leprosy cases detected. Seroprevalence was significantly lower at private schools. No differences in the patterns of seropositivity between ELISA and dipstick were observed. No correlation between Leprosy detection rate and seropositivity rates could be established.
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the ml flow test as a point of care test for Leprosy Control programmes potential effects on classification of Leprosy patients
Leprosy Review, 2007Co-Authors: Samira Buhrersekula, P R Klatser, Jan Visschedijk, Maria Aparecida De Faria Grossi, Krishna P Dhakal, Abdullahi U Namadi, Linda OskamAbstract:OBJECTIVE: To evaluate the use of the ML Flow test as an additional, serological, tool for the classification of new Leprosy patients. DESIGN: In Brazil, Nepal and Nigeria, 2632 Leprosy patients were classified by three METHODS: : (1) as multibacillary (MB) or paucibacillary (PB) according to the number of skin lesions (WHO classification), (2) by slit skin smear examination, and (3) by serology using the ML Flow test detecting IgM antibodies to Mycobacterium leprae-specific phenolic glycolipid-I. RESULTS: The proportion of MB Leprosy patients was 39.5, 35.6 and 19.4% in Brazil, Nepal and Nigeria, respectively. The highest seropositivity in patients was observed in Nigeria (62.9%), followed by Brazil (50.8%) and Nepal (35.6%). ML Flow test results and smears were negative in 69.1 and 82.7% of PB patients, while smears were positive in 58.6% of MB patients in Brazil and 28.3% in Nepal. In MB patients, both smears and ML Flow tests were negative in 15.6% in Brazil and 38.3%, in Nepal. Testing all PB patients with the ML Flow test to prevent under-treatment would increase the MB group by 18, 11 and 46.2% for Brazil, Nepal and Nigeria, respectively. Using the ML Flow test as the sole criterion for classification would result in an increase of 11.3 and 43.5% of patients requiring treatment for MB Leprosy in Brazil and Nigeria, respectively, and a decrease of 3.7% for Nepal. CONCLUSIONS: The ML Flow test could be used to strengthen classification, reduce the risk of under-treatment and minimize the need for slit skin smears.
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a study on transmission and a trial of chemoprophylaxis in contacts of Leprosy patients design methodology and recruitment findings of colep
Leprosy Review, 2004Co-Authors: Fake J Moet, Linda Oskam, Roel Faber, David Pahan, Jan Hendrik RichardusAbstract:In this article, we describe the design, methodology and recruitment findings of the COLEP study. The objectives of this study were to determine the effectiveness of chemoprophylaxis with a single dose of rifampicin in the prevention of Leprosy among close contacts of Leprosy patients, and to find characteristics of contact groups most at risk to develop clinical Leprosy. These characteristics should be usable by routine Leprosy Control programmes. COLEP consists of a cluster randomized, double-blind and placebo-Controlled trial, a cohort study to determine risk factors characterizing the sub-groups most at risk within the total contact group of a patient, and a cohort study using a reference group from the general population to determine the prevalence and incidence of Leprosy in the total population of the study area. The follow-up period will be 4 years. A coding system was developed describing the physical and genetic distance of the contact person to the patient. This study in Bangladesh includes 1037 newly diagnosed and previously untreated Leprosy patients and their 21,867 contacts. The prevalence of Leprosy among contacts was 7.3 per 1000. A total of 21,708 contacts without signs and symptoms of clinical Leprosy are included in a trial of chemoprophylaxis with single dose rifampicin, and randomized at contact group level in treatment and placebo arms. The results of this large field trial will become available in the years to come.
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simple and fast lateral flow test for classification of Leprosy patients and identification of contacts with high risk of developing Leprosy
Journal of Clinical Microbiology, 2003Co-Authors: Samira Buhrersekula, Henk L Smits, George C Gussenhoven, J Van Leeuwen, S Amador, T Fujiwara, P R Klatser, Linda OskamAbstract:The interruption of Leprosy transmission is one of the main challenges for Leprosy Control programs since no consistent evidence exists that transmission has been reduced after the introduction of multidrug therapy. Sources of infection are primarily people with high loads of bacteria with or without clinical signs of Leprosy. The availability of a simple test system for the detection of antibodies to phenolic glycolipid-I (PGL-I) of Mycobacterium leprae to identify these individuals may be important in the prevention of transmission. We have developed a lateral flow assay, the ML Flow test, for the detection of antibodies to PGL-I which takes only 10 min to perform. An agreement of 91% was observed between enzyme-linked immunosorbent assay and our test; the agreement beyond chance (kappa value) was 0.77. We evaluated the use of whole blood by comparing 539 blood and serum samples from an area of high endemicity. The observed agreement was 85.9% (kappa = 0.70). Storage of the lateral flow test and the running buffer at 28°C for up to 1 year did not influence the results of the assay. The sensitivity of the ML Flow test in correctly classifying MB patients was 97.4%. The specificity of the ML Flow test, based on the results of the Control group, was 90.2%. The ML Flow test is a fast and easy-to-perform method for the detection of immunoglobulin M antibodies to PGL-I of M. leprae. It does not require any special equipment, and the highly stable reagents make the test robust and suitable for use in tropical countries.
Marc Bonenberger - One of the best experts on this subject based on the ideXlab platform.
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Leprosy post exposure prophylaxis with single dose rifampicin lpep an international feasibility programme
The Lancet Global Health, 2021Co-Authors: Jan Hendrik Richardus, Anuj Tiwari, Tanja Barthjaeggi, Mohammad Arif, Nand Lal Banstola, Rabindra Baskota, David D Blaney, David J Blok, Marc BonenbergerAbstract:Summary 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.
George C Gussenhoven - One of the best experts on this subject based on the ideXlab platform.
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A SIMPLE DIPSTICK ASSAY FOR THE DETECTION OF ANTIBODIES TO PHENOLIC GLYCOLIPID-I OF MYCOBACTERIUM LEPRAE
2015Co-Authors: Samira Bu S. Hrer, Henk L Smits, George C Gussenhoven, C. W. Van Ingen, R. KlatserAbstract:Abstract. Among the many reported applications of the detection of antibodies to phenolic glycolipid-I (PGL-I) of Mycobacterium leprae, in particular, the use of seroprevalence as an indicator of the magnitude of the Leprosy problem may turn out to be very useful in Leprosy Control programs. An operational function of serology within the Leprosy Control services requires a simple test system. We have developed a simple dipstick assay for the detection of antibodies to PGL-I and compared its performance with that of an ELISA. A high degree of agreement (97.2%) was observed between the ELISA and the dipstick assay when tested on 435 sera; the agreement beyond chance (Kappa value) was 0.92. No significant difference was found between the dipstick assay and the ELISA when seropositivity rates obtained in groups of Leprosy patients, household contacts, and Controls were compared. The interpretation of the dipstick results as positive or negative was unequivocal, as illustrated by the high agreement between different persons reading the test (Kappa values. 0.88). Storage of the only reagents required, the dipsticks and the stabilized detection reagent, up to three weeks under tropical conditions of high temperatures, high humidity, and exposure to light, did not influence the results of the assay. The dipstick assay described here is an easy-to-perform method for the detection of IgM antibodies to PGL-I of M. leprae; it does not require any special equipment and the highly stable reagents make the test robust and suitable for use in tropical countries. An internal Control validates the performance of the assay. This dipstick assay may be the method of choice for epidemiologic mappin
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simple and fast lateral flow test for classification of Leprosy patients and identification of contacts with high risk of developing Leprosy
Journal of Clinical Microbiology, 2003Co-Authors: Samira Buhrersekula, Henk L Smits, George C Gussenhoven, J Van Leeuwen, S Amador, T Fujiwara, P R Klatser, Linda OskamAbstract:The interruption of Leprosy transmission is one of the main challenges for Leprosy Control programs since no consistent evidence exists that transmission has been reduced after the introduction of multidrug therapy. Sources of infection are primarily people with high loads of bacteria with or without clinical signs of Leprosy. The availability of a simple test system for the detection of antibodies to phenolic glycolipid-I (PGL-I) of Mycobacterium leprae to identify these individuals may be important in the prevention of transmission. We have developed a lateral flow assay, the ML Flow test, for the detection of antibodies to PGL-I which takes only 10 min to perform. An agreement of 91% was observed between enzyme-linked immunosorbent assay and our test; the agreement beyond chance (kappa value) was 0.77. We evaluated the use of whole blood by comparing 539 blood and serum samples from an area of high endemicity. The observed agreement was 85.9% (kappa = 0.70). Storage of the lateral flow test and the running buffer at 28°C for up to 1 year did not influence the results of the assay. The sensitivity of the ML Flow test in correctly classifying MB patients was 97.4%. The specificity of the ML Flow test, based on the results of the Control group, was 90.2%. The ML Flow test is a fast and easy-to-perform method for the detection of immunoglobulin M antibodies to PGL-I of M. leprae. It does not require any special equipment, and the highly stable reagents make the test robust and suitable for use in tropical countries.
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A SIMPLE DIPSTICK ASSAY FOR THE DETECTION OF ANTIBODIES TO PHENOLIC GLYCOLIPID-I OF MYCOBACTERIUM LEPRAE
The American journal of tropical medicine and hygiene, 1998Co-Authors: S S Bührer, Henk L Smits, George C Gussenhoven, C. W. Van Ingen, P R KlatserAbstract:Among the many reported applications of the detection of antibodies to phenolic glycolipid-I (PGL-I) of Mycobacterium leprae, in particular, the use of seroprevalence as an indicator of the magnitude of the Leprosy problem may turn out to be very useful in Leprosy Control programs. An operational function of serology within the Leprosy Control services requires a simple test system. We have developed a simple dipstick assay for the detection of antibodies to PGL-I and compared its performance with that of an ELISA. A high degree of agreement (97.2%) was observed between the ELISA and the dipstick assay when tested on 435 sera; the agreement beyond chance (Kappa value) was 0.92. No significant difference was found between the dipstick assay and the ELISA when seropositivity rates obtained in groups of Leprosy patients, household contacts, and Controls were compared. The interpretation of the dipstick results as positive or negative was unequivocal, as illustrated by the high agreement between different persons reading the test (Kappa values > 0.88). Storage of the only reagents required, the dipsticks and the stabilized detection reagent, up to three weeks under tropical conditions of high temperatures, high humidity, and exposure to light, did not influence the results of the assay. The dipstick assay described here is an easy-to-perform method for the detection of IgM antibodies to PGL-I of M. leprae; it does not require any special equipment and the highly stable reagents make the test robust and suitable for use in tropical countries. An internal Control validates the performance of the assay. This dipstick assay may be the method of choice for epidemiologic mapping of Leprosy.