1
|
da Silva MB, Li W, Bouth RC, Gobbo AR, Messias ACC, Moraes TMP, Jorge EVO, Barreto JG, Filho FB, Conde GAB, Frade MAC, Salgado CG, Spencer JS. Latent leprosy infection identified by dual RLEP and anti-PGL-I positivity: Implications for new control strategies. PLoS One 2021; 16:e0251631. [PMID: 33984058 PMCID: PMC8118453 DOI: 10.1371/journal.pone.0251631] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 04/30/2021] [Indexed: 11/20/2022] Open
Abstract
The number of new cases of leprosy reported worldwide has remained essentially unchanged for the last decade despite continued global use of free multidrug therapy (MDT) provided to any diagnosed leprosy patient. In order to more effectively interrupt the chain of transmission, new strategies will be required to detect those with latent disease who contribute to furthering transmission. To improve the ability to diagnose leprosy earlier in asymptomatic infected individuals, we examined the combined use of two well-known biomarkers of M. leprae infection, namely the presence of M. leprae DNA by PCR from earlobe slit skin smears (SSS) and positive antibody titers to the M. leprae-specific antigen, Phenolic Glycolipid I (anti-PGL-I) from leprosy patients and household contacts living in seven hyperendemic cities in the northern state of Pará, Brazilian Amazon. Combining both tests increased sensitivity, specificity and accuracy over either test alone. A total of 466 individuals were evaluated, including 87 newly diagnosed leprosy patients, 52 post-treated patients, 296 household contacts and 31 healthy endemic controls. The highest frequency of double positives (PGL-I+/RLEP+) were detected in the new case group (40/87, 46%) with lower numbers for treated (12/52, 23.1%), household contacts (46/296, 15.5%) and healthy endemic controls (0/31, 0%). The frequencies in these groups were reversed for double negatives (PGL-I-/RLEP-) for new cases (6/87, 6.9%), treated leprosy cases (15/52, 28.8%) and the highest in household contacts (108/296, 36.5%) and healthy endemic controls (24/31, 77.4%). The data strongly suggest that household contacts that are double positive have latent disease, are likely contributing to shedding and transmission of disease to their close contacts and are at the highest risk of progressing to clinical disease. Proposed strategies to reduce leprosy transmission in highly endemic areas may include chemoprophylactic treatment of this group of individuals to stop the spread of bacilli to eventually lower new case detection rates in these areas.
Collapse
Affiliation(s)
- Moises Batista da Silva
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
| | - Wei Li
- Colorado State University, Department of Microbiology, Immunology and Pathology, Mycobacteria Research Laboratories, Fort Collins, CO, Unites States of America
| | - Raquel Carvalho Bouth
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
| | - Angélica Rita Gobbo
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
| | - Ana Caroline Cunha Messias
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
| | - Tania Mara Pires Moraes
- Instituto de Saúde Coletiva, Universidade Federal do Oeste do Pará (UFOPA), Santarém, Pará, Brazil
| | - Erika Vanessa Oliveira Jorge
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
| | - Josafá Gonçalves Barreto
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
- Spatial Epidemiology Laboratory, Universidade Federal do Pará—Campus Castanhal, Castanhal, Pará, Brazil
| | - Fred Bernardes Filho
- Division of Dermatology, Department of Internal Medicine of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | | | - Marco Andrey Cipriani Frade
- Division of Dermatology, Department of Internal Medicine of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Claudio Guedes Salgado
- Laboratório de Dermato-Imunologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belem, Pará, Brazil
| | - John Stewart Spencer
- Colorado State University, Department of Microbiology, Immunology and Pathology, Mycobacteria Research Laboratories, Fort Collins, CO, Unites States of America
- * E-mail:
| |
Collapse
|
2
|
Blok DJ, Steinmann P, Tiwari A, Barth-Jaeggi T, Arif MA, Banstola NL, Baskota R, Blaney D, Bonenberger M, Budiawan T, Cavaliero A, Gani Z, Greter H, Ignotti E, Kamara DV, Kasang C, Manglani PR, Mieras L, Njako BF, Pakasi T, Saha UR, Saunderson P, Smith WCS, Stäheli R, Suriyarachchi ND, Tin Maung A, Shwe T, van Berkel J, van Brakel WH, Vander Plaetse B, Virmond M, Wijesinghe MSD, Aerts A, Richardus JH. The long-term impact of the Leprosy Post-Exposure Prophylaxis (LPEP) program on leprosy incidence: A modelling study. PLoS Negl Trop Dis 2021; 15:e0009279. [PMID: 33788863 PMCID: PMC8011751 DOI: 10.1371/journal.pntd.0009279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 02/26/2021] [Indexed: 01/04/2023] Open
Abstract
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. 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.
Collapse
Affiliation(s)
- David J. Blok
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- * E-mail:
| | - Peter Steinmann
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Anuj Tiwari
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Tanja Barth-Jaeggi
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | | | | | - David Blaney
- Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | | | | | | | | | - Helena Greter
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | | | - Christa Kasang
- German Leprosy and Tuberculosis Relief Association, Würzburg, Germany
| | | | | | - Blasdus F. Njako
- German Leprosy and Tuberculosis Relief Association, Dar es Salaam, Tanzania
| | - Tiara Pakasi
- Ministry of Health of the Republic of Indonesia, Jakarta, Indonesia
| | - Unnati R. Saha
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Paul Saunderson
- American Leprosy Missions, Greenville, South Carolina, United States of America
| | | | | | | | | | - Tin Shwe
- American Leprosy Missions, Yangon, Myanmar
| | | | | | | | | | | | - Ann Aerts
- Novartis Foundation, Basel, Switzerland
| | - Jan Hendrik Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| |
Collapse
|
3
|
Patients with skin smear positive leprosy in Bangladesh are the main risk factor for leprosy development: 21-year follow-up in the household contact study (COCOA). PLoS Negl Trop Dis 2020; 14:e0008687. [PMID: 33125403 PMCID: PMC7598483 DOI: 10.1371/journal.pntd.0008687] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 08/10/2020] [Indexed: 01/19/2023] Open
Abstract
Background Leprosy transmission is ongoing; globally and within Bangladesh. Household contacts of leprosy cases are at increased risk of leprosy development. Identification of household contacts at highest risk would optimize this process. Methods The temporal pattern of new case presentation amongst household contacts was documented in the COCOA (Contact Cohort Analysis) study. The COCOA study actively examined household contacts of confirmed leprosy index cases identified in 1995, and 2000–2014, to provide evidence for timings of contact examination policies. Data was available on 9527 index cases and 38303 household contacts. 666 household contacts were diagnosed with leprosy throughout the follow-up (maximum follow-up of 21 years). Risk factors for leprosy development within the data analysed, were identified using Cox proportional hazard regression. Findings The dominant risk factor for household contacts developing leprosy was having a highly skin smear positive index case in the household. As the grading of initial slit skin smear of the index case increased from negative to high positive (4–6), the hazard of their associated household contacts developing leprosy increases by 3.14 times (p<0.001). Being a blood relative was not a risk factor, no gender differences in susceptibility were found. Interpretation We found a dominance of a single variable predicting risk for leprosy transmission–skin smear positive index cases. A small number of cases are maintaining transmission in the household setting. Focus should be performing contact examinations on these households and detecting new skin smear positive index cases. Conducting slit-skin smears on new cases is needed for predicting risk; such services need supporting. If skin smear positive cases are sustaining leprosy infection within the household setting, the administration of single-dose rifampicin (SDR) to household contacts as the sole intervention in Bangladesh will not be effective. The number of newly detected leprosy cases worldwide has remained stable over the last ten years. Household contacts of leprosy cases are at increased risk of leprosy development. Household contact examinations and case detection are critical aspects of control. Specific risk factors (recognizable by field staff) for leprosy development need to be identified to aid these control efforts. Targeted household examinations could increase early case detection: this is important because untreated leprosy cases are sustaining transmission. This is the largest, most comprehensive study of development of leprosy in household contacts conducted recently with a maximum follow-up of 21 years. We found a single dominant risk factor for the development of leprosy in the household setting, namely slit skin smear positivity in the index case. This is important for leprosy control because household contact examinations can be focused on contacts at highest risk. Implementation would be simple as the risk factor is identified by leprosy staff in the field. Prioritising households known to be at highest risk of leprosy development would allow efficient allocation of resources. Our results cast doubt on the success of administering the recommended prophylactic intervention for contacts; the use of this intervention needs to be re-evaluated.
Collapse
|
4
|
Abstract
Nepal has long been known as a leprosy endemic country. However, in 2010, the application of World Health Organization guidelines in Nepal led to the misleading determination that leprosy had been 'eliminated' there. This misnomer has contributed to the current situation in which leprosy is on the increase. A national active case finding program is urgently required.
Collapse
|
5
|
Albuquerque ARD, Silva JVDM, Barreto EDO, Fraga CADC, Santos WOD, Silva MSMD, Souza CDFD, Sales-Marques C. Epidemiological, temporal and spatial dynamics of leprosy in a municipality in northeastern Brazil (2008-2017): an ecological study. Rev Soc Bras Med Trop 2020; 53:e20200246. [PMID: 33111909 PMCID: PMC7580284 DOI: 10.1590/0037-8682-0246-2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/13/2020] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION Leprosy is a chronic infectious disease caused by Mycobacterium leprae.This study aimed to analyze the epidemiological, temporal, and spatial dynamics ofleprosy in a municipality in northeastern Brazil. METHODS This is an ecological study on new leprosy cases in the population of Arapiraca (Alagoas, Northeast Region, Brazil), from 2008 to 2017. Data extracted from a national database were analyzed forepidemiological indicators, factors associated with physical disabilities, and spatialanalysis in the neighborhoods of Arapiraca. RESULTS A total of 292 new cases of leprosy were recorded, particularly occurring among the following groups: women, the age group of 46-59 years, brown-skinned individuals, people with less than eight years of schooling, and urban residents; the new cases were also predominantly the tuberculoid form and were of the paucibacillary classification of the disease. Almost 1/3 of the people had some degree of physical disability, which was mainly associated with the group 60 years of age and older, black ethnicity, and the multibacillary clinical form of leprosy. The joinpoint regression showed a stationary temporal behavior of indicators. There was a heterogeneous spatial distribution with active transmission areas, especially in the neighborhoods Primavera, Baixão, Ouro Preto, and downtown. CONCLUSIONS The epidemiological indicators revealed complexity in the process of leprosy development. These spatial and temporal studies are relevant to help in the planning, monitoring, and guidance of interventions in the municipality. The spatial analysis showed heterogeneous distribution in the analyzed neighborhoods.
Collapse
Affiliation(s)
| | | | - Emiliano de Oliveira Barreto
- Universidade Federal de Alagoas, Instituto de Ciências Biológicas e da Saúde, Laboratório de Biologia Celular, A/C Simões, AL, Brasil
| | | | | | | | | | - Carolinne Sales-Marques
- Universidade Federal de Alagoas, Centro de Ciências Médicas e Enfermagem, Curso de Medicina, Arapiraca, AL, Brasil
- Universidade Federal de Alagoas, Centro de Ciências Médicas e Enfermagem, Laboratório de Biologia Molecular e Expressão Gênica, Arapiraca, AL, Brasil
| |
Collapse
|
6
|
Palit A, Kar H. Prevention of transmission of leprosy: The current scenario. Indian J Dermatol Venereol Leprol 2020; 86:115-123. [DOI: 10.4103/ijdvl.ijdvl_326_19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
7
|
Richardus R, Alam K, Kundu K, Chandra Roy J, Zafar T, Chowdhury AS, Nieboer D, Faber R, Butlin CR, Geluk A, Richardus JH. Effectiveness of single-dose rifampicin after BCG vaccination to prevent leprosy in close contacts of patients with newly diagnosed leprosy: A cluster randomized controlled trial. Int J Infect Dis 2019; 88:65-72. [PMID: 31499206 DOI: 10.1016/j.ijid.2019.08.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 08/28/2019] [Accepted: 08/31/2019] [Indexed: 10/26/2022] Open
Abstract
OBJECTIVE To assess the effectiveness of single-dose rifampicin (SDR) after bacillus Calmette-Guérin (BCG) vaccination in preventing leprosy in contacts. METHODS This was a single-centre, cluster-randomized controlled trial at a leprosy control programme in northwest Bangladesh. Participants were the 14988 contacts of 1552 new leprosy patients who were randomized into the SDR-arm (n=7379) and the SDR+arm (n=7609). In the intervention group, BCG vaccination was followed by SDR 8-12 weeks later. In the control group, BCG vaccination only was given. Follow-up was performed at 1year and 2 years after intake. The main outcome measure was the occurrence of leprosy. RESULTS The incidence rate per 10000 person-years at risk was 44 in the SDR-arm and 31 in the SDR+arm at 1year; the incidence rate was 34 in the SDR-arm and 41 in the SDR+arm at 2 years. There was a statistically non-significant (p=0.148; 42%) reduction for paucibacillary (PB) leprosy in the SDR+ arm at 1 year. Of all new cases, 33.6% appeared within 8-12 weeks after BCG vaccination. CONCLUSIONS In the first year, SDR after BCG vaccination reduced the incidence of PB leprosy among contacts by 42%. This was a statistically non-significant reduction due to the limited number of cases after SDR was administered. To what extent SDR suppresses excess leprosy cases after BCG vaccination is difficult to establish because many cases appeared before the SDR intervention. TRIAL REGISTRATION Netherlands Trial Register: NTR3087.
Collapse
Affiliation(s)
- Renate Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands; Department of Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands
| | - Khorshed Alam
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Kallyan Kundu
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Johan Chandra Roy
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Tasnuva Zafar
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Abu Sufian Chowdhury
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Daan Nieboer
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Roel Faber
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - C Ruth Butlin
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Annemieke Geluk
- Department of Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands
| | - Jan Hendrik Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
| |
Collapse
|
8
|
Leturiondo AL, Noronha AB, do Nascimento MOO, Ferreira CDO, Rodrigues FDC, Moraes MO, Talhari C. Performance of serological tests PGL1 and NDO-LID in the diagnosis of leprosy in a reference Center in Brazil. BMC Infect Dis 2019; 19:22. [PMID: 30616580 PMCID: PMC6322275 DOI: 10.1186/s12879-018-3653-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 12/21/2018] [Indexed: 12/12/2022] Open
Abstract
Background Early detection of leprosy and multidrug therapy are crucial to achieve zero transmission and zero grade II incapacities goals of World Health Organization. Leprosy is difficult to diagnose because clinical forms vary and there are no gold standard methods to guide clinicians. The serological rapid tests aid the clinical diagnosis and are available for field use. They are easy to perform, do not require special equipment or refrigeration and are cheaper than the molecular tests. Methods We evaluated the performance of two rapid serological tests (PGL1 and NDO-LID) in the discrimination of leprosy cases from healthy individuals at the Alfredo da Matta Foundation, a reference center for the disease in Manaus, Amazonas, Brazil. PGL1 and NDO-LID rapid tests are capable of detecting specific antibodies of M. leprae, IgM and IgM/IgG, respectively. A total of 530 healthy subjects and 171 patients (50 with paucibacillary and 121 multibacillary leprosy) were included in the study. Results Among the paucibacillary leprosy patients, the sensitivity was 34.0 and 32.0% for the NDO-LID and PGL1, respectively. In multibacillary leprosy patients, the NDO-LID sensitivity was 73.6% and the PGL1 was 81.0%. Serological tests demonstrated specificities of 75.9% for PGL-1 and 81.7% for NDO-LID. The positive predictive value (PPV), negative predictive value (NPV) and accuracy in multibacillary patients were 47.9, 93.1, and 80.2% respectively for the NDO-LID, and 43.4, 94.6 76.8% for PGL1. Conclusions The tests showed limited capacity in the diagnosis of the disease, however, the high negative predictive value of the tests indicates a greater chance of true negatives in this group favoring exclusion of leprosy. This characteristic of the ML flow test is important in aiding clinical Diagnosis, especially in a region endemic to the disease and with other confounding skin conditions. Electronic supplementary material The online version of this article (10.1186/s12879-018-3653-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- André Luiz Leturiondo
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas, Manaus, Amazonas, Brazil. .,Fundação Alfredo da Matta, Av Codajás 24, Cachoeirinha, Manaus, Amazonas, Brazil.
| | | | | | | | | | - Milton Ozório Moraes
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carolina Talhari
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas, Manaus, Amazonas, Brazil.,Fundação Alfredo da Matta, Av Codajás 24, Cachoeirinha, Manaus, Amazonas, Brazil.,Universidade Nilton Lins, Manaus, Amazonas, Brazil
| |
Collapse
|
9
|
Duthie MS, Pena MT, Ebenezer GJ, Gillis TP, Sharma R, Cunningham K, Polydefkis M, Maeda Y, Makino M, Truman RW, Reed SG. LepVax, a defined subunit vaccine that provides effective pre-exposure and post-exposure prophylaxis of M. leprae infection. NPJ Vaccines 2018; 3:12. [PMID: 29619252 PMCID: PMC5871809 DOI: 10.1038/s41541-018-0050-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/15/2018] [Accepted: 02/20/2018] [Indexed: 12/19/2022] Open
Abstract
Sustained elimination of leprosy as a global health concern likely requires a vaccine. The current standard, BCG, confers only partial protection and precipitates paucibacillary (PB) disease in some instances. When injected into mice with the T helper 1 (Th1)-biasing adjuvant formulation Glucopyranosyl Lipid Adjuvant in stable emulsion (GLA-SE), a cocktail of three prioritized antigens (ML2055, ML2380 and ML2028) reduced M. leprae infection levels. Recognition and protective efficacy of a single chimeric fusion protein incorporating these antigens, LEP-F1, was confirmed in similar experiments. The impact of post-exposure immunization was then assessed in nine-banded armadillos that demonstrate a functional recapitulation of leprosy. Armadillos were infected with M. leprae 1 month before the initiation of post-exposure prophylaxis. While BCG precipitated motor nerve conduction abnormalities more rapidly and severely than observed for control infected armadillos, motor nerve injury in armadillos treated three times, at monthly intervals with LepVax was appreciably delayed. Biopsy of cutaneous nerves indicated that epidermal nerve fiber density was not significantly altered in M. leprae-infected animals although Remak Schwann cells of the cutaneous nerves in the distal leg were denser in the infected armadillos. Importantly, LepVax immunization did not exacerbate cutaneous nerve involvement due to M. leprae infection, indicating its safe use. There was no intraneural inflammation but a reduction of intra axonal edema suggested that LepVax treatment might restore some early sensory axonal function. These data indicate that post-exposure prophylaxis with LepVax not only appears safe but, unlike BCG, alleviates and delays the neurologic disruptions caused by M. leprae infection. A leprosy vaccine candidate has been developed that raises immune responses against targets gleaned from naturally resistant individuals. Researchers from the United States and Japan, led by Malcolm Duthie, of Seattle’s Infectious Disease Research Institute, tested a Mycobacterium leprae vaccine candidate that generated immune responses mimicking those found in partially-resistant patients, and immune co-inhabitants of the severely infected. The candidate, dubbed LepVax, inhibited infection in mice and, when administered post-infection, delayed and mitigated nerve damage in armadillos. This contrasts with the current vaccine, BCG, which can precipitate leprosy symptoms when given after infection. This study also revealed that M. leprae infection can induce ‘silent’ pre-clinical nerve aberations. High-risk populations may already be infected with M. leprae, making safe and effective post-exposure prophylaxis a landmark step in combating both the individual and global burden of leprosy.
Collapse
Affiliation(s)
- Malcolm S Duthie
- 1Infectious Disease Research Institute, 1616 Eastlake Ave E, Suite 400, Seattle, WA 98102 USA
| | - Maria T Pena
- National Hansens Disease Programs, Baton Rouge, LA USA
| | - Gigi J Ebenezer
- 3Department of Neurology, Johns Hopkins University, Baltimore, MD 21209 USA
| | - Thomas P Gillis
- 4Department of Microbiology, Immunology and Parasitology, LSU School of Medicine, New Orleans, LA USA
| | - Rahul Sharma
- National Hansens Disease Programs, Baton Rouge, LA USA
| | - Kelly Cunningham
- 3Department of Neurology, Johns Hopkins University, Baltimore, MD 21209 USA
| | - Michael Polydefkis
- 3Department of Neurology, Johns Hopkins University, Baltimore, MD 21209 USA
| | - Yumi Maeda
- 5Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Masahiko Makino
- 5Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Richard W Truman
- 6Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA USA
| | - Steven G Reed
- 1Infectious Disease Research Institute, 1616 Eastlake Ave E, Suite 400, Seattle, WA 98102 USA
| |
Collapse
|
10
|
Marçal PHF, Fraga LADO, Mattos AMMD, Menegati L, Coelho ADCO, Pinheiro RO, Sarno EN, Duthie MS, Teixeira HC. Utility of immunoglobulin isotypes against LID-1 and NDO-LID for, particularly IgG1, confirming the diagnosis of multibacillary leprosy. Mem Inst Oswaldo Cruz 2018. [PMID: 29513821 PMCID: PMC5851060 DOI: 10.1590/0074-02760170467] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Leprosy remains a health problem in many countries, with difficulties in
diagnosis resulting in delayed treatment and more severe disabilities.
Antibodies against several Mycobacterium leprae antigens
have, however, shown value as diagnostic and/or prognostic markers. OBJECTIVES The objective of this study was to evaluate serum immunoglobulin (Ig) IgM
and IgG subclass reactivity against three M. leprae
specific antigens: NDO-HSA, a conjugate formed by natural octyl disaccharide
bound to human serum albumin; LID-1, the fusion protein product of the
ml0405 and ml2331 genes; and NDO-LID, a combination of LID-1 and NDO. METHODS Sera from healthy controls, paucibacillary (PB) and multibacillary (MB)
leprosy patients, and their respective household contacts, were evaluated
for the presence of antigen-specific IgM, IgG, and IgG subclass antibodies
by enzyme-linked immunosorbent assay (ELISA). The sensitivity and
specificity of each ELISA were evaluated by receiver operating
characteristic (ROC) curve analysis. FINDINGS Our data confirm that serum IgM antibodies against NDO-HSA and IgG
antibodies against LID-1, as well as IgG/M antibodies against NDO-LID, are
markedly increased in MB patients. For the first time, our data reveal a
selective increase in IgG1 and IgG3 antibodies against LID-1 and NDO-LID in
MB patients, demonstrating that these antibody isotypes are suitable for
differentiation between MB and PB patients. ROC curve analysis indicates an
improved capacity for diagnosing MB leprosy patients using the detection of
IgG antibodies, particularly the IgG1 isotype, specific to LID-1 and NDO-LID
over the performance levels attained with NDO-HSA. CONCLUSIONS Our findings indicate that serological tests based on the detection of
antigen-specific IgG1 antibodies are a useful tool to differentiate MB from
PB patients, and indicate the enhanced performance of the LID-1 and NDO-LID
antigens in the serodiagnosis of leprosy.
Collapse
Affiliation(s)
- Pedro Henrique Ferreira Marçal
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brasil
| | | | - Ana Márcia Menezes de Mattos
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brasil
| | - Laura Menegati
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brasil
| | | | - Roberta Olmo Pinheiro
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brasil
| | - Euzenir Nunes Sarno
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brasil
| | | | - Henrique Couto Teixeira
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brasil
| |
Collapse
|
11
|
Bernardes F, Paula NAD, Leite MN, Abi-Rached TLC, Vernal S, Silva MBD, Barreto JG, Spencer JS, Frade MAC. Evidence of hidden leprosy in a supposedly low endemic area of Brazil. Mem Inst Oswaldo Cruz 2017; 112:822-828. [PMID: 29211243 PMCID: PMC5719551 DOI: 10.1590/0074-02760170173] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 06/30/2017] [Indexed: 12/03/2022] Open
Abstract
OBJECTIVES Show that hidden endemic leprosy exists in a municipality of inner São Paulo
state (Brazil) with active surveillance actions based on clinical and
immunological evaluations. METHODS The study sample was composed by people randomly selected by a dermatologist
during medical care in the public emergency department and by active
surveillance carried out during two days at a mobile clinic. All subjects
received a dermato-neurological examination and blood sampling to determine
anti-PGL-I antibody titers by enzyme-linked immunosorbent assay (ELISA). RESULTS From July to December 2015, 24 new cases of leprosy were diagnosed; all were
classified as multibacillary (MB) leprosy, one with severe Lucio's
phenomenon. Seventeen (75%) were found with grade-1 or 2 disability at the
moment of diagnosis. Anti-PGL-I titer was positive in 31/133 (23.3%)
individuals, only 6/24 (25%) were positive in newly diagnosed leprosy
cases. CONCLUSIONS During the last ten years before this study, the average new case detection
rate (NCDR) in this town was 2.62/100,000 population. After our work, the
NCDR was raised to 42.8/100,000. These results indicate a very high number
of hidden leprosy cases in this supposedly low endemic area of Brazil.
Collapse
Affiliation(s)
- Fred Bernardes
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Clínica Médica, Divisão de Dermatologia, Ribeirão Preto, SP, Brasil
| | - Natália Aparecida de Paula
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Clínica Médica, Divisão de Dermatologia, Ribeirão Preto, SP, Brasil
| | - Marcel Nani Leite
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Clínica Médica, Divisão de Dermatologia, Ribeirão Preto, SP, Brasil
| | - Thania Loyola Cordeiro Abi-Rached
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Clínica Médica, Divisão de Dermatologia, Ribeirão Preto, SP, Brasil
| | - Sebastian Vernal
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Clínica Médica, Divisão de Dermatologia, Ribeirão Preto, SP, Brasil
| | | | - Josafá Gonçalves Barreto
- Universidade Federal do Pará, Laboratório de Dermato-Imunologia, Marituba, PA, Brasil.,Universidade Federal do Pará, Laboratório de Epidemiologia Espacial, Castanhal, PA, Brasil
| | - John Stewart Spencer
- Colorado State University, Department of Microbiology, Immunology and Pathology, Fort Collins, CO, USA
| | - Marco Andrey Cipriani Frade
- Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Clínica Médica, Divisão de Dermatologia, Ribeirão Preto, SP, Brasil
| |
Collapse
|
12
|
Richardus RA, van der Zwet K, van Hooij A, Wilson L, Oskam L, Faber R, van den Eeden SJF, Pahan D, Alam K, Richardus JH, Geluk A. Longitudinal assessment of anti-PGL-I serology in contacts of leprosy patients in Bangladesh. PLoS Negl Trop Dis 2017; 11:e0006083. [PMID: 29228004 PMCID: PMC5746281 DOI: 10.1371/journal.pntd.0006083] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/28/2017] [Accepted: 10/30/2017] [Indexed: 12/23/2022] Open
Abstract
Background Despite elimination efforts, the number of Mycobacterium leprae (M. leprae) infected individuals who develop leprosy, is still substantial. Solid evidence exists that individuals living in close proximity to patients are at increased risk to develop leprosy. Early diagnosis of leprosy in endemic areas requires field-friendly tests that identify individuals at risk of developing the disease before clinical manifestation. Such assays will simultaneously contribute to reduction of current diagnostic delay as well as transmission. Antibody (Ab) levels directed against the M.leprae-specific phenolic glycolipid I (PGL-I) represents a surrogate marker for bacterial load. However, it is insufficiently defined whether anti-PGL-I antibodies can be utilized as prognostic biomarkers for disease in contacts. Particularly, in Bangladesh, where paucibacillary (PB) patients form the majority of leprosy cases, anti-PGL-I serology is an inadequate method for leprosy screening in contacts as a directive for prophylactic treatment. Methods Between 2002 and 2009, fingerstick blood from leprosy patients’ contacts without clinical signs of disease from a field-trial in Bangladesh was collected on filter paper at three time points covering six years of follow-up per person. Analysis of anti-PGL-I Ab levels for 25 contacts who developed leprosy during follow-up and 199 contacts who were not diagnosed with leprosy, was performed by ELISA after elution of bloodspots from filter paper. Results Anti-PGL-I Ab levels at intake did not significantly differ between contacts who developed leprosy during the study and those who remained free of disease. Moreover, anti-PGL-I serology was not prognostic in this population as no significant correlation was identified between anti-PGL-I Ab levels at intake and the onset of leprosy. Conclusion In this highly endemic population in Bangladesh, no association was observed between anti-PGL-I Ab levels and onset of disease, urging the need for an extended, more specific biomarker signature for early detection of leprosy in this area. Trial registration ClinicalTrials.gov ISRCTN61223447 Leprosy is an infectious disease caused by the bacterium Mycobacterium leprae, which causes skin and nerve damage. Despite worldwide efforts to eliminate leprosy, the number of infected individuals who develop leprosy, is still substantial. Household contacts of new leprosy patients are especially at risk. Early diagnosis of leprosy is key in preventing lifelong handicaps as well as transmission. This requires field-friendly tests that identify individuals at risk of developing the disease before they develop clinical symptoms so that they can receive (prophylactic) treatment. Measuring antibody levels directed against the M.leprae-specific phenolic glycolipid I (PGL-I) provides an indication of the bacterial load. To identify whether anti-PGL-I Ab levels correlate with the development of leprosy in contacts of newly diagnosed leprosy cases, we analyzed these levels in 25 contacts who developed leprosy during 6 years of follow-up and 199 contacts who were not diagnosed with leprosy at 3 time points in 6 years. This study showed that anti-PGL-I Ab levels at intake did not significantly differ between contacts who developed leprosy during the study and those who remained free of disease. Therefore, anti-PGL-I Ab levels alone do not represent a practical tool for prediction of which household contacts will develop leprosy in an endemic area such as Bangladesh, with high levels of patients with paucibacillary leprosy. This stresses the need for a diagnostic test composed of a biomarker signature consisting of multiple biomarkers.
Collapse
Affiliation(s)
- Renate A. Richardus
- Department of Infectious Diseases Leiden University Medical Center, Leiden, The Netherlands
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Konrad van der Zwet
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Anouk van Hooij
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Louis Wilson
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Linda Oskam
- KIT Biomedical Research, Royal Tropical Institute, Amsterdam, The Netherlands
| | - Roel Faber
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | | | - David Pahan
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Khorshed Alam
- Rural Health Program, The Leprosy Mission International Bangladesh, Nilphamari, Bangladesh
| | - Jan Hendrik Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Annemieke Geluk
- Department of Infectious Diseases Leiden University Medical Center, Leiden, The Netherlands
- * E-mail:
| |
Collapse
|
13
|
Amorim FM, Nobre ML, Ferreira LC, Nascimento LS, Miranda AM, Monteiro GRG, Dupnik KM, Duthie MS, Reed SG, Jeronimo SMB. Identifying Leprosy and Those at Risk of Developing Leprosy by Detection of Antibodies against LID-1 and LID-NDO. PLoS Negl Trop Dis 2016; 10:e0004934. [PMID: 27658042 PMCID: PMC5033353 DOI: 10.1371/journal.pntd.0004934] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 07/29/2016] [Indexed: 11/19/2022] Open
Abstract
Leprosy is caused by Mycobacterium leprae infection and remains a major public health problem in many areas of the world. Challenges to its timely diagnosis result in delay in treatment, which is usually associated with severe disability. Although phenolic glycolipid (PGL)-I has been reported as auxiliary diagnostic tool, currently there is no serological assay routinely used in leprosy diagnosis. The aim of this study was to evaluate the effectiveness of two related reagents, LID-1 and LID-NDO, for the detection of M. leprae infection. Sera from 98 leprosy patients, 365 household contacts (HHC) and 98 endemic controls from Rio Grande do Norte, Brazil, were evaluated. A subgroup of the HHC living in a hyperendemic area was followed for 7–10 years. Antigen-specific antibody responses were highest in multibacillary (MB) at the lepromatous pole (LL/BL) and lowest in paucibacillary (PB) at the tuberculoid pole (TT/BT). A positive correlation for both anti-LID-1 and anti-LID-NDO antibodies was found with bacterial burden (LID-1, r = 0.84, p<0.001; LID-NDO, r = 0.82, p<0.001), with higher sensitivity than bacilloscopy. According to Receiver Operating Curve, LID-1 and LID-NDO performed similarly. The sensitivity for MB cases was 89% for LID-1 and 95% for LID-NDO; the specificity was 96% for LID-1 and 88% for LID-NDO. Of the 332 HHC that were followed, 12 (3.6%) were diagnosed with leprosy in a median time of 31 (3–79) months after recruitment. A linear generalized model using LID-1 or LID-NDO as a predictor estimated that 8.3% and 10.4% of the HHC would become a leprosy case, respectively. Together, our findings support a role for the LID-1 and LID-NDO antigens in diagnosing MB leprosy and identifying people at greater risk of developing clinical disease. These assays have the potential to improve the diagnostic capacity at local health centers and aid development of strategies for the eventual control and elimination of leprosy from endemic areas. Despite the substantial decrease in its prevalence, leprosy continues to be a worldwide challenge. Early diagnosis and treatment are important to interrupt transmission. Currently, there is no gold standard for the diagnosis of leprosy. Bacilloscopy and histopathology studies are complementary exams that provide high specificity but low sensitivity. It is therefore important to seek alternative tools to achieve rapid and accurate diagnosis. The state of Rio Grande do Norte, in Brazil, has municipalities’ that are considered hyperendemic for leprosy, such as Mossoró, the one included in this study. This city presented an average of new case detection rate (NCDR) of 45.4/100.000 inhabitants per year from 2001 to 2013, much higher than Brazil’s NCDR, which is currently 15.3. Here, we show that the utility of the recombinant antigens LID-1 and LID-NDO to diagnose MB patients and detect asymptomatic M. leprae infection. In addition, we showed that antibody levels were related to the clinical form of leprosy as well as to the bacillary load. Interestingly, we observed that serum levels of LID-1/LID-NDO antibodies can be used to predict leprosy development among HHC. The assays have the potential to eventually be implemented as point of care at local health centers.
Collapse
Affiliation(s)
- Francianne M. Amorim
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | - Maurício L. Nobre
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
- Post-graduate Program in Tropical Medicine, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
- Hospital Giselda Trigueiro, Rio Grande do Norte Health Secretariat, Natal, Rio Grande do Norte, Brazil
| | - Leonardo C. Ferreira
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | - Larissa S. Nascimento
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | - Alesson M. Miranda
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | - Glória R. G. Monteiro
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | - Kathryn M. Dupnik
- Center for Global Health, Weill Cornell Medical College, New York, New York, United States of America
| | - Malcolm S. Duthie
- Infectious Disease Research Institute, Seattle, Washington, United States of America
| | - Steven G. Reed
- Infectious Disease Research Institute, Seattle, Washington, United States of America
| | - Selma M. B. Jeronimo
- Department of Biochemistry, Bioscience Center, and Institute of Tropical Medicine of Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
- Instituto Nacional de Ciência e Tecnologia de Doenças Tropicais (INCT-DT), Salvador, Bahia, Brazil
- * E-mail:
| |
Collapse
|
14
|
Kumar A, Girdhar A, Chakma JK. Increase in cases of leprosy in the Firozabad district of India: a two-time cross-sectional survey. Br J Dermatol 2016; 176:520-522. [PMID: 27344048 DOI: 10.1111/bjd.14823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A Kumar
- Department of Biostatistics and Epidemiology, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Taj Ganj, Agra, 282004, India
| | - A Girdhar
- Department of Clinical Sciences, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Taj Ganj, Agra, 282004, India
| | - J K Chakma
- Department of Clinical Sciences, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Taj Ganj, Agra, 282004, India
| |
Collapse
|
15
|
Duthie MS, Balagon MF. Combination chemoprophylaxis and immunoprophylaxis in reducing the incidence of leprosy. Risk Manag Healthc Policy 2016; 9:43-53. [PMID: 27175099 PMCID: PMC4854245 DOI: 10.2147/rmhp.s76058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Leprosy is a complex infectious disease caused by Mycobacterium leprae that is a leading cause of nontraumatic peripheral neuropathy. Current control strategies, with a goal of early diagnosis and treatment in the form of multidrug therapy, have maintained new case reports at ~225,000 per year. Diagnostic capabilities are limited and even with revisions to multidrug therapy regimen, treatment can still require up to a year of daily drug intake. Although alternate chemotherapies or adjunct immune therapies that could provide shorter or simpler treatment regimen appear possible, only a limited number of trials have been conducted. More proactive strategies appear necessary in the drive to elimination. As a prevention strategy, most chemoprophylaxis campaigns to date have provided about a 2-year protective window. Vaccination, in the form of a single bacillus Calmette–Guérin (BCG) immunization, generally provides ~50% reduction in leprosy cases. Adapting control strategies to provide both chemoprophylaxis and immunoprophylaxis has distinct appeal, with chemoprophylaxis theoretically buttressed by vaccination to generate immediate protection that can be sustained in the long term. We also discuss simple assays measuring biomarkers as surrogates for disease development or replacements for invasive, but not particularly sensitive, direct measures of M. leprae infection. Such assays could facilitate the clinical trials required to develop these new chemoprophylaxis, immunoprophylaxis strategies, and transition into wider use.
Collapse
Affiliation(s)
| | - Marivic F Balagon
- Cebu Skin Clinic, Leonard Wood Memorial Center for Leprosy Research, Cebu City, the Philippines
| |
Collapse
|
16
|
Scollard DM, Dacso MM, Abad-Venida ML. Tuberculosis and Leprosy: Classical Granulomatous Diseases in the Twenty-First Century. Dermatol Clin 2016; 33:541-62. [PMID: 26143431 DOI: 10.1016/j.det.2015.03.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Leprosy and tuberculosis are chronic mycobacterial infections that elicit granulomatous inflammation. Both infections are curable, but granulomatous injury to cutaneous structures, including cutaneous nerves in leprosy, may cause permanent damage. Both diseases are major global concerns: tuberculosis for its high prevalence and mortality, and leprosy for its persistent global presence and high rate of neuropathic disability. Cutaneous manifestations of both leprosy and tuberculosis are frequently subtle and challenging in dermatologic practice and often require a careful travel and social history and a high index of suspicion.
Collapse
Affiliation(s)
- David M Scollard
- National Hansen's Disease Programs, 1770 Physician Park Drive, Baton Rouge, LA 70816, USA.
| | - Mara M Dacso
- Center for Dermatology and Cosmetic Laser Surgery, 5026 Tennyson Parkway, Plano, TX 75024, USA; Department of Dermatology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9069, USA
| | - Ma Luisa Abad-Venida
- Department of Dermatology, Jose R. Reyes Memorial Medical Center, Rizal Avenue, Manila 1008, Philippines
| |
Collapse
|
17
|
de Matos HJ, Blok DJ, de Vlas SJ, Richardus JH. Leprosy New Case Detection Trends and the Future Effect of Preventive Interventions in Pará State, Brazil: A Modelling Study. PLoS Negl Trop Dis 2016; 10:e0004507. [PMID: 26938738 PMCID: PMC4777416 DOI: 10.1371/journal.pntd.0004507] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/11/2016] [Indexed: 11/18/2022] Open
Abstract
Background Leprosy remains a public health problem in Brazil. Although the overall number of new cases is declining, there are still areas with a high disease burden, such as Pará State in the north of the country. We aim to predict future trends in new case detection rate (NCDR) and explore the potential impact of contact tracing and chemoprophylaxis on NCDR in Pará State. Methods We used SIMCOLEP, an existing individual-based model for the transmission and control of M. leprae, in a population structured by households. The model was quantified to simulate the population and observed NCDR of leprosy in Pará State for the period 1990 to 2014. The baseline scenario was the current control program, consisting of multidrug therapy, passive case detection, and active case detection from 2003 onwards. Future projections of the NCDR were made until 2050 given the continuation of the current control program (i.e. baseline). We further investigated the potential impact of two scenarios for future control of leprosy: 1) discontinuation of contact tracing; and 2) continuation of current control in combination with chemoprophylaxis. Both scenarios started in 2015 and were projected until 2050. Results The modelled NCDR in Pará State after 2014 shows a continuous downward trend, reaching the official elimination target of 10 cases per 100,000 population by 2030. The cessation of systematic contact tracing would not result in a higher NCDR in the long run. Systematic contact tracing in combination with chemoprophylaxis for contacts would reduce the NCDR by 40% and bring attainment of the elimination target two years forward to 2028. Conclusion The NCDR of leprosy continues to decrease in Pará State. Elimination of leprosy as a public health problem could possibly be achieved around 2030, if the current control program is maintained. Providing chemoprophylaxis would decrease the NCDR further and would bring elimination forward by two years. Leprosy remains a public health problem in Brazil. With over 30,000 new cases detected annually, it has the second-largest number of leprosy cases detected worldwide. Although the overall number of new cases is declining, there are still areas with a high disease burden, such as Pará State. In this study, we used the individual-based model SIMCOLEP to predict the future trend of the new case detection rate of leprosy (NCDR) in Pará State given the current control strategy. Additionally, we explored the potential impact of contact tracing and chemoprophylaxis on the NCDR. Our results show that the NCDR continues to decrease in Para State, reaching elimination around 2030. Contact tracing alone would not further reduce the NCDR. However, when contact tracing is combined with chemoprophylaxis the NCDR would be reduced up to 40% and elimination could be brought forward by two years.
Collapse
Affiliation(s)
- Haroldo José de Matos
- Instituto Evandro Chagas, Belém, Pará, Brazil
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - David J. Blok
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- * E-mail:
| | - Sake J. de Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jan Hendrik Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| |
Collapse
|
18
|
Abstract
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-Guérin (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.
Collapse
|
19
|
da Conceição Oliveira Coelho Fabri A, Carvalho APM, Araujo S, Goulart LR, de Mattos AMM, Teixeira HC, Goulart IMB, Duthie MS, Correa-Oliveira R, Lana FCF. Antigen-specific assessment of the immunological status of various groups in a leprosy endemic region. BMC Infect Dis 2015; 15:218. [PMID: 26021317 PMCID: PMC4448205 DOI: 10.1186/s12879-015-0962-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 05/21/2015] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Serological tests can be important tools to assist in the diagnosis of leprosy and can contribute to an earlier diagnosis. The aim of this study was to evaluate the antibody responses against phenolic glycolipid-1 (PGL-1), natural disaccharide linked to human serum albumin via an octyl (NDO-HSA), Leprosy IDRI Diagnostic-1 (LID-1) and natural disaccharide octyl--Leprosy IDRI Diagnostic-1 (NDO-LID) in leprosy patients, household contacts of patients and the general population. METHODS Enzyme-linked immunosorbent assays were used to analyze the antigen-specific antibody responses of 94 leprosy cases, 104 household contacts of cases and 2.494 individuals from the general population. RESULTS A positive correlation was observed for the antibody responses to all antigens studied. A higher proportion of seropositivity for all antigens, along with stronger magnitude of response, was observed in multibacillary (MB) leprosy patients and household contacts of MB leprosy patients compared with the levels observed in paucibacillary (PB) leprosy patients and household contacts of PB leprosy patients. A substantial and significant positive correlation was found between seropositivity and the bacterial index for the leprosy patients. Anti-PGL-1 tests were more frequently positive than anti-NDO-HSA tests among patients with all clinical forms of leprosy and among the group of household contacts. The LID-1 and NDO-LID antigens showed a greater capacity to identify household contacts and individuals from the general population infected with M. leprae. CONCLUSIONS Tests that measure the antibody responses against LID-1, NDO-LID, NDO-HSA and PGL-1 were effective tools for the detection of patients with MB leprosy. Our data indicate that the anti-LID-1 and anti-NDO-LID responses were more effective than an anti-NDO-HSA response for the identification of individuals with subclinical infection.
Collapse
Affiliation(s)
- Angélica da Conceição Oliveira Coelho Fabri
- Department of Basic Nursing, Faculdade de Enfermagem, Universidade Federal de Juiz de Fora - UFJF, Juiz de Fora, MG, Brazil.
- Postgraduate Program in Nursing, Escola de Enfermagem, Universidade Federal de Minas Gerais - UFMG, Belo Horizonte, MG, Brazil.
| | - Ana Paula Mendes Carvalho
- Postgraduate Program in Nursing, Escola de Enfermagem, Universidade Federal de Minas Gerais - UFMG, Belo Horizonte, MG, Brazil.
| | - Sergio Araujo
- National Reference Center for Sanitary Dermatology and Leprosy - CREDESH, Hospital das Clínicas, Universidade Federal de Uberlandia - UFU, Uberlândia, MG, Brazil.
| | - Luiz Ricardo Goulart
- Institute of Genetics and Biochemistry, Universidade Federal de Uberlandia - UFU, Uberlândia, MG, Brazil.
- Department of Medical Microbiology and Immunology, University of California-Davis, Davis, CA, USA.
| | - Ana Márcia Menezes de Mattos
- Postgraduate Program in Biological Science - Immunology and Infectious Parasitic Disease, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora - UFJF, Juiz de Fora, MG, Brazil.
| | - Henrique Couto Teixeira
- Department of Parasitology, Microbiology and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora - UFJF, Juiz de Fora, MG, Brazil.
| | - Isabela Maria Bernardes Goulart
- National Reference Center for Sanitary Dermatology and Leprosy - CREDESH, Hospital das Clínicas, Universidade Federal de Uberlandia - UFU, Uberlândia, MG, Brazil.
| | | | - Rodrigo Correa-Oliveira
- Postgraduate Program in Nursing, Escola de Enfermagem, Universidade Federal de Minas Gerais - UFMG, Belo Horizonte, MG, Brazil.
- Laboratory of Cellular and Molecular Immunology, Centro de Pesquisas René Rachou - CPqRR, Fundação Oswaldo Cruz - FIOCRUZ, Belo Horizonte, MG, Brazil.
- Laboratory of Immunology, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto - UFOP, Ouro Preto, MG, Brazil.
- Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais - INCT-DT, Belo Horizonte, Brazil.
| | - Francisco Carlos Félix Lana
- Postgraduate Program in Nursing, Escola de Enfermagem, Universidade Federal de Minas Gerais - UFMG, Belo Horizonte, MG, Brazil.
- Department of Maternal and Child Nursing and Public Health, Escola de Enfermagem, Universidade Federal de Minas Gerais - UFMG, Belo Horizonte, MG, Brazil.
| |
Collapse
|
20
|
Wagenaar I, van Muiden L, Alam K, Bowers R, Hossain MA, Kispotta K, Richardus JH. Diet-related risk factors for leprosy: a case-control study. PLoS Negl Trop Dis 2015; 9:e0003766. [PMID: 25965879 PMCID: PMC4428634 DOI: 10.1371/journal.pntd.0003766] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 04/16/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Food shortage was associated with leprosy in two recent studies investigating the relation between socioeconomic factors and leprosy. Inadequate intake of nutrients due to food shortage may affect the immune system and influence the progression of infection to clinical leprosy. We aimed to identify possible differences in dietary intake between recently diagnosed leprosy patients and control subjects. METHODS In a leprosy endemic area of Bangladesh, newly diagnosed leprosy patients and control subjects were interviewed about their socioeconomic situation, health and diet. Dietary intakes were recorded with a 24-hour recall, from which a Dietary Diversity Score (DDS) was calculated. Body Mass Index (BMI) was calculated and Household Food Insecurity Access Scale (HFIAS) was filled out for every participant. Using logistic regression, a univariate, block wise multivariate, and an integrated analysis were carried out. RESULTS 52 leprosy cases and 100 control subjects were included. Food shortage was more common, dietary diversity was lower and household food insecurity was higher in the patient group. Patients consumed significantly less items from the DDS food groups 'Meat and fish' and 'Other fruits and vegetables.' Lower food expenditure per capita, lower BMI, lower DDS and absence of household food stocks are the main factors associated with an increased risk of having leprosy. CONCLUSION Low income families have only little money to spend on food and consequently have a low intake of highly nutritious non-rice foods such as meat, fish, milk, eggs, fruits and vegetables. Development of clinical leprosy could be explained by deficiencies of the nutrients that these foods normally provide.
Collapse
Affiliation(s)
- Inge Wagenaar
- Department of Public Health, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Khorshed Alam
- Rural Health Program, The Leprosy Mission International-Bangladesh, Nilphamari, Bangladesh
| | - Robert Bowers
- Rural Health Program, The Leprosy Mission International-Bangladesh, Nilphamari, Bangladesh
| | - Md. Anwar Hossain
- Nilphamari Training Center, The Leprosy Mission International-Bangladesh, Nilphamari, Bangladesh
| | - Kolpona Kispotta
- Nilphamari Training Center, The Leprosy Mission International-Bangladesh, Nilphamari, Bangladesh
| | | |
Collapse
|
21
|
de Souza MM, Netto EM, Nakatani M, Duthie MS. Utility of recombinant proteins LID-1 and PADL in screening for Mycobacterium leprae infection and leprosy. Trans R Soc Trop Med Hyg 2014; 108:495-501. [DOI: 10.1093/trstmh/tru093] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
22
|
Barreto JG, Bisanzio D, Guimarães LDS, Spencer JS, Vazquez-Prokopec GM, Kitron U, Salgado CG. Spatial analysis spotlighting early childhood leprosy transmission in a hyperendemic municipality of the Brazilian Amazon region. PLoS Negl Trop Dis 2014; 8:e2665. [PMID: 24516679 PMCID: PMC3916250 DOI: 10.1371/journal.pntd.0002665] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 12/12/2013] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND More than 200,000 new cases of leprosy were reported by 105 countries in 2011. The disease is a public health problem in Brazil, particularly within high-burden pockets in the Amazon region where leprosy is hyperendemic among children. METHODOLOGY We applied geographic information systems and spatial analysis to determine the spatio-temporal pattern of leprosy cases in a hyperendemic municipality of the Brazilian Amazon region (Castanhal). Moreover, we performed active surveillance to collect clinical, epidemiological and serological data of the household contacts of people affected by leprosy and school children in the general population. The occurrence of subclinical infection and overt disease among the evaluated individuals was correlated with the spatio-temporal pattern of leprosy. PRINCIPAL FINDINGS The pattern of leprosy cases showed significant spatio-temporal heterogeneity (p<0.01). Considering 499 mapped cases, we found spatial clusters of high and low detection rates and spatial autocorrelation of individual cases at fine spatio-temporal scales. The relative risk of contracting leprosy in one specific cluster with a high detection rate is almost four times the risk in the areas of low detection rate (RR = 3.86; 95% CI = 2.26-6.59; p<0.0001). Eight new cases were detected among 302 evaluated household contacts: two living in areas of clusters of high detection rate and six in hyperendemic census tracts. Of 188 examined students, 134 (71.3%) lived in hyperendemic areas, 120 (63.8%) were dwelling less than 100 meters of at least one reported leprosy case, 125 (66.5%) showed immunological evidence (positive anti-PGL-I IgM titer) of subclinical infection, and 9 (4.8%) were diagnosed with leprosy (8 within 200 meters of a case living in the same area). CONCLUSIONS/SIGNIFICANCE Spatial analysis provided a better understanding of the high rate of early childhood leprosy transmission in this region. These findings can be applied to guide leprosy control programs to target intervention to high risk areas.
Collapse
Affiliation(s)
- Josafá Gonçalves Barreto
- Laboratório de Dermato-Imunologia UEPA/UFPA/Marcello Candia, Marituba, Pará, Brasil
- Universidade Federal do Pará, Campus Castanhal, Pará, Brasil
| | - Donal Bisanzio
- Department of Environmental Studies, Emory University, Atlanta, Georgia, United States of America
| | - Layana de Souza Guimarães
- Unidade de Referência Especializada em Dermatologia Sanitária Dr. Marcello Candia, Marituba, Pará, Brasil
| | - John Stewart Spencer
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | | | - Uriel Kitron
- Department of Environmental Studies, Emory University, Atlanta, Georgia, United States of America
| | - Claudio Guedes Salgado
- Laboratório de Dermato-Imunologia UEPA/UFPA/Marcello Candia, Marituba, Pará, Brasil
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil
| |
Collapse
|
23
|
Calado KLS, Magnanini MMF, Moura RSD, Gallo MEN, Bührer-Sékula S, Oliveira MLWDRD. Serology with ML Flow test in health professionals from three different states of Brazil. An Bras Dermatol 2014; 88:918-23. [PMID: 24474100 PMCID: PMC3900342 DOI: 10.1590/abd1806-4841.20132139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 01/11/2013] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND In highly endemic countries, transmission and sub-clinical infection of leprosy
are likely and the disease manifests itself in individuals without any known close
contact with a leprosy patient. Health workers are social contacts belonging to
the same network (the Health System) and some of them share the same social
environment (nursing assistants) as patients with known patients and / or
carriers. OBJECTIVE To identify ML Flow seropositivity among health professionals. METHODS We conducted a cross-sectional study using a serological survey with the ML Flow
test in 450 health professionals (doctors, nurses and nursing assistants), in
order to detect seropositivity in areas of high and low endemicity in
municipalities from three Brazilian states (RJ, MS and RS). RESULTS The results showed general 16% seropositivity, higher in low endemic areas,
regardless of whether there was direct care for leprosy patients. Paradoxically, a
statistical association was observed between the area studied and seropositivity,
as the place with the lowest endemicity (CA) had the highest seropositivity rate
(p = 0.033). CONCLUSION The authors suggest these results are associated with a presence of an
unspecified link to bovine serum albumin (BSA), carrier of PGL-1 in the ML Flow
test, and recommend expanded seroepidemiological research utilizing tests with
human and bovine albumin.
Collapse
Affiliation(s)
- Karla Lucena Sampaio Calado
- Federal University of Rio de Janeiro, Rio de JaneiroRJ, Brazil, Master's in Dermatology, Federal University of Rio de Janeiro (UFRJ) - Assistant Professor of Dermatology, Federal University of Grande Dourados (UFGD). PhD in Tropical Medicine from the Oswaldo Cruz Foundation (FIOCRUZ) - Rio de Janeiro (RJ), Brazil
| | - Mônica Maria Ferreira Magnanini
- Oswaldo Cruz Foundation, Rio de JaneiroRJ, Brazil, PhD in Public Health from the Oswaldo Cruz Foundation (FIOCRUZ). Statistics, Federal University of Rio de Janeiro (UFRJ) - Rio de Janeiro (RJ), Brazil
| | - Rodrigo Scaliante de Moura
- Federal University of Goiás, GoiâniaGO, Brazil, Biomedical doctor. Master's in Tropical Medicine, Federal University of Goiás (UFG) - Goiânia (GO), Brazil
| | - Maria Eugenia Noviski Gallo
- Oswaldo Cruz Foundation, Rio de JaneiroRJ, Brazil, PhD in Tropical Medicine from the Oswaldo Cruz Foundation (FIOCRUZ). Professor at the Oswaldo Cruz Foundation (FIOCRUZ) - Rio de Janeiro (RJ), Brazil
| | - Samira Bührer-Sékula
- Universiteit van Amsterdam, Netherlands, Netherlands, PhD in Immunology from the Universiteit van Amsterdam, Netherlands - Collaborating Professor at the Federal University of Goiás (UFG) - Goiânia (GO), Brazil
| | - Maria Leide Wand-Del-Rey de Oliveira
- Federal University of Rio de Janeiro, Rio de JaneiroRJ, Brazil, PhD in Dermatology from the Federal University of Rio de Janeiro (UFRJ)-Federal Adjuct Professor, University of Rio de Janeiro (UFRJ), Rio de Janeiro (RJ), Brazil
| |
Collapse
|
24
|
Feenstra SG, Nahar Q, Pahan D, Oskam L, Richardus JH. A qualitative exploration of social contact patterns relevant to airborne infectious diseases in northwest Bangladesh. JOURNAL OF HEALTH, POPULATION, AND NUTRITION 2013; 31:424-34. [PMID: 24592583 PMCID: PMC3905636 DOI: 10.3329/jhpn.v31i4.19976] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In South Asia, the burden of infectious diseases is high. Socioeconomically and culturally-defined social interaction patterns are considered to be an important determinant in the spread of diseases that are transmitted through person-to-person contact. Understanding of the contact patterns in this region can be helpful to develop more effective control measures. Focus group discussions were used in exploring social contact patterns in northwest Bangladesh. The patterns were assessed for perceived relevance to the spread of airborne infectious diseases, with special focus on diseases, like leprosy and tuberculosis, in which the role of social determinants is well-recognized. Highly-relevant social contact patterns inside the home and the neighbourhood, across age and sex groups, were reported in all group discussions. Outside the home, women and girls reported relevant contacts limited to the close neighbourhood while men mentioned high relevant contacts beyond. This implies that, in theory, infectious diseases can easily be transmitted across age and sex groups in and around the home. Adult men might play a role in the transmission of airborne infectious diseases from outside this confined area since only this group reported highly-relevant social contacts beyond the home. This concept needs further exploration but control programmes in the South Asian region could benefit from considering differences in social contact patterns by gender for risk assessments and planning of preventive interventions.
Collapse
Affiliation(s)
- Sabiena G Feenstra
- Erasmus MC, University Medical Center Rotterdam, Department of Public Health, Rotterdam, The Netherlands.
| | - Quamrun Nahar
- Centre for Population, Urbanization and Climate Change, Dhaka 1000, Bangladesh
| | - David Pahan
- Rural Health Program Nilphamari, The Leprosy Mission International Bangladesh, Dhaka, Bangladesh
| | - Linda Oskam
- KIT Biomedical Research, Amsterdam, The Netherlands
| | - Jan Hendrik Richardus
- Erasmus MC, University Medical Center Rotterdam, Department of Public Health, Rotterdam, The Netherlands
| |
Collapse
|
25
|
Duthie MS, Saunderson P, Reed SG. The potential for vaccination in leprosy elimination: new tools for targeted interventions. Mem Inst Oswaldo Cruz 2013; 107 Suppl 1:190-6. [PMID: 23283471 DOI: 10.1590/s0074-02762012000900027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 07/17/2012] [Indexed: 05/27/2023] Open
Abstract
Despite the huge effort and massive advances toward the elimination of leprosy over the last two decades, the disease has proven stubborn; new case detection rates have stabilised over the last few years and leprosy remains endemic in a number of localised regions. The American Leprosy Missions and Infectious Disease Research Institute have undertaken a large research effort aimed at developing new tools and a vaccine to continue the push for leprosy elimination. In this paper, we outline our strategy for the integration of rapid diagnostic tests and lab-based assays to facilitate the detection of early or asymptomatic leprosy cases, as well as the efficient and focused implementation of chemoprophylaxis and immunisation to intervene in leprosy development and transmission.
Collapse
|
26
|
Barreto JG, Guimarães LDS, Frade MAC, Rosa PS, Salgado CG. High rates of undiagnosed leprosy and subclinical infection amongst school children in the Amazon Region. Mem Inst Oswaldo Cruz 2013; 107 Suppl 1:60-7. [PMID: 23283455 DOI: 10.1590/s0074-02762012000900011] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 07/18/2012] [Indexed: 11/22/2022] Open
Abstract
Leprosy in children is correlated with community-level factors, including the recent presence of disease and active foci of transmission in the community. We performed clinical and serological examinations of 1,592 randomly selected school children (SC) in a cross-sectional study of eight hyperendemic municipalities in the Brazilian Amazon Region. Sixty-three (4%) SC, with a mean age of 13.3 years (standard deviation = 2.6), were diagnosed with leprosy and 777 (48.8%) were seropositive for anti-phenolic glycolipid-I (PGL-I). Additionally, we evaluated 256 house-hold contacts (HHCs) of the students diagnosed with leprosy; 24 (9.4%) HHC were also diagnosed with leprosy and 107 (41.8%) were seropositive. The seroprevalence of anti-PGL-I was significantly higher amongst girls, students from urban areas and students from public schools (p < 0.0001). Forty-five (71.4%) new cases detected amongst SC were classified as paucibacillary and 59 (93.6%) patients did not demonstrate any degree of physical disability at diagnosis. The results of this study suggest that there is a high rate of undiagnosed leprosy and subclinical infection amongst children in the Amazon Region. The advantages of school surveys in hyperendemic areas include identifying leprosy patients at an early stage when they show no physical disabilities, preventing the spread of the infection in the community and breaking the chain of transmission.
Collapse
|
27
|
Spencer JS, Duthie MS, Geluk A, Balagon MF, Kim HJ, Wheat WH, Chatterjee D, Jackson M, Li W, Kurihara JN, Maghanoy A, Mallari I, Saunderson P, Brennan PJ, Dockrell HM. Identification of serological biomarkers of infection, disease progression and treatment efficacy for leprosy. Mem Inst Oswaldo Cruz 2013; 107 Suppl 1:79-89. [PMID: 23283458 DOI: 10.1590/s0074-02762012000900014] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 07/25/2012] [Indexed: 11/21/2022] Open
Abstract
Although leprosy is curable with drug treatment, the identification of biomarkers of infection, disease progression and treatment efficacy would greatly help to reduce the overall prevalence of the disease. Reliable biomarkers would also reduce the incidence of grade-2 disability by ensuring that those who are most at risk are diagnosed and treated early or offered repeated treatments in the case of relapse. In this study, we examined the reactivity of sera from lepromatous and tuberculoid leprosy patients (LPs) against a panel of 12 recombinant Mycobacterium leprae proteins and found that six proteins were strongly recognised by multibacillary (MB) patients, while only three were consistently recognised by paucibacillary patients. To better understand the dynamics of patient antibody responses during and after drug therapy, we measured antibody titres to four recombinant proteins, phenolic glycolipid-I and lipoarabinomannan at baseline and up to two years after diagnosis to investigate the temporal changes in the antibody titres. Reactivity patterns to individual antigens and decreases in antibody titres were patient-specific. Antibody titres to proteins declined more rapidly vs. those to carbohydrate and glycolipid antigens. Compared to baseline values, increases in antibody titres were observed during reactional episodes in one individual. Additionally, antibody responses against a subset of antigens that provided a good prognostic indicator of disease progression were analysed in 51 household contacts of MB index cases for up to two years. Although the majority of these contacts showed no change or exhibited decreases in antibody titres, seven individuals developed higher titres towards one or more of these antigens and one individual with progressively higher titres was diagnosed with borderline lepromatous leprosy 19 months after enrolment. The results of this study indicate that antibody titres to specific M. leprae antigens can be used to monitor treatment efficacy in LPs and assess disease progression in those most at risk for developing this disease.
Collapse
Affiliation(s)
- John S Spencer
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Richardus RA, Alam K, Pahan D, Feenstra SG, Geluk A, Richardus JH. The combined effect of chemoprophylaxis with single dose rifampicin and immunoprophylaxis with BCG to prevent leprosy in contacts of newly diagnosed leprosy cases: a cluster randomized controlled trial (MALTALEP study). BMC Infect Dis 2013; 13:456. [PMID: 24088534 PMCID: PMC3850918 DOI: 10.1186/1471-2334-13-456] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 09/30/2013] [Indexed: 11/29/2022] Open
Abstract
Background Despite almost 30 years of effective chemotherapy with MDT, the global new case detection rate of leprosy has remained quite constant over the past years. New tools and methodologies are necessary to interrupt the transmission of M. leprae. Single-dose rifampicin (SDR) has been shown to prevent 57% of incident cases of leprosy in the first two years, when given to contacts of newly diagnosed cases. Immunization of contacts with BCG has been less well documented, but appears to have a preventive effect lasting up to 9 years. However, one major disadvantage is the occurrence of excess cases within the first year after immunization. The objective of this study is to examine the effect of chemoprophylaxis with SDR and immunoprophylaxis with BCG on the clinical outcome as well as on host immune responses and gene expression profiles in contacts of newly diagnosed leprosy patients. We hypothesize that the effects of both interventions may be complementary, causing the combined preventive outcome to be significant and long-lasting. Methods/design Through a cluster randomized controlled trial we compare immunization with BCG alone with BCG plus SDR in contacts of new leprosy cases. Contact groups of around 15 persons will be established for each of the 1300 leprosy patients included in the trial, resulting in approximately 20,000 contacts in total. BCG will be administered to the intervention group followed by SDR, 2 months later. The control group will receive BCG only. In total 10,000 contacts will be included in both intervention arms over a 2-year period. Follow-up will take place one year as well as two years after intake. The primary outcome is the occurrence of clinical leprosy within two years. Simultaneously with vaccination and SDR, blood samples for in vitro analyses will be obtained from 300 contacts participating in the trial to determine the effect of these chemo- and immunoprophylactic interventions on immune and genetic host parameters. Discussion Combined chemoprophylaxis and immunoprophylaxis is potentially a very powerful and innovative tool aimed at contacts of leprosy patients that could reduce the transmission of M. leprae markedly. The trial intends to substantiate this potential preventive effect. Evaluation of immune and genetic biomarker profiles will allow identification of pathogenic versus (BCG-induced) protective host biomarkers and could lead to effective prophylactic interventions for leprosy using optimized tools for identification of individuals who are most at risk of developing disease. Trial registration Netherlands Trial Register: NTR3087
Collapse
Affiliation(s)
- Renate A Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, P,O, Box 2040, 3000, CA Rotterdam, The Netherlands.
| | | | | | | | | | | |
Collapse
|
29
|
FEENSTRA SG, NAHAR Q, PAHAN D, OSKAM L, RICHARDUS JH. Social contact patterns and leprosy disease: a case-control study in Bangladesh. Epidemiol Infect 2013; 141:573-81. [PMID: 22583511 PMCID: PMC9167658 DOI: 10.1017/s0950268812000969] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 04/15/2012] [Accepted: 04/18/2012] [Indexed: 11/06/2022] Open
Abstract
Socioeconomic and culturally defined social contact patterns are expected to be an important determinant in the continuing transmission of Mycobacterium leprae in leprosy-endemic areas. In a case-control study in two districts in Bangladesh, we assessed the association between social contact patterns and the risk of acquiring clinical leprosy. Social contacts of 90 recently diagnosed patients were compared to those of 199 controls. Leprosy was associated with a more intensive social contact pattern in the home [odds ratio (OR) 1·09, 95% confidence interval (CI) 1·00-1·19, P = 0·043] and in the nearby neighbourhood (OR 1·07, 95% CI 1·03-1·11, P = 0·001). Although it is known that M. leprae spreads most easily within households of infected persons, in endemic areas social contacts within the neighbourhood, village or urban ward, also appear to be important for transmission. We advise that disease control measures in leprosy-endemic areas should not be limited to households, but include high-risk groups in the nearby neighbourhood of patients.
Collapse
Affiliation(s)
- S. G. FEENSTRA
- Erasmus MC, University Medical Center Rotterdam, Department of Public Health, Rotterdam, The Netherlands
| | - Q. NAHAR
- ICDDR, B, Health Systems and Infectious Diseases Division, Dhaka, Bangladesh
| | - D. PAHAN
- The Leprosy Mission International Bangladesh, Rural Health Program, Dhaka, Bangladesh
| | - L. OSKAM
- KIT Biomedical Research, Amsterdam, The Netherlands
| | - J. H. RICHARDUS
- Erasmus MC, University Medical Center Rotterdam, Department of Public Health, Rotterdam, The Netherlands
| |
Collapse
|
30
|
Salgado CG, Ferreira DVG, Frade MAC, Guimarães LDS, da Silva MB, Barreto JG. High anti-phenolic glycolipid-I IgM titers and hidden leprosy cases, Amazon region. Emerg Infect Dis 2012; 18:889-90. [PMID: 22515845 PMCID: PMC3358075 DOI: 10.3201/eid1805.111018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
31
|
Duthie MS, Gillis TP, Reed SG. Advances and hurdles on the way toward a leprosy vaccine. HUMAN VACCINES 2011; 7:1172-83. [PMID: 22048122 DOI: 10.4161/hv.7.11.16848] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Prevalence rates for leprosy have declined sharply over the past 20 y, with this decline generally attributed to the WHO multi-drug therapy (MDT) campaign to provide free-of-charge treatment to all diagnosed leprosy patients. The success of this program appears to have reached its nadir, however, as evidenced by the stalled decreases in both global prevalence and new case detection rates of leprosy. Mass BCG vaccination for the prevention of tuberculosis (TB) at national levels has had a positive effect on leprosy decline and is often overlooked as an important factor in current leprosy control programs. Because BCG provides incomplete protection against both TB and leprosy, newer more effective TB vaccines are being developed. The impact that application of these vaccines will have on current leprosy control programs is unclear. In this review, we assess the need for vaccines within leprosy control programs. We summarize and discuss leprosy vaccine strategies that have been deployed previously and discuss those strategies that are currently being developed to augment recent breakthroughs in leprosy control.
Collapse
|
32
|
Fischer EAJ, de Vlas SJ, Habbema JDF, Richardus JH. The long-term effect of current and new interventions on the new case detection of leprosy: a modeling study. PLoS Negl Trop Dis 2011; 5:e1330. [PMID: 21949895 PMCID: PMC3176744 DOI: 10.1371/journal.pntd.0001330] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 08/10/2011] [Indexed: 11/19/2022] Open
Abstract
Background Although the number of newly detected leprosy cases has decreased globally, a quarter of a million new cases are detected annually and eradication remains far away. Current options for leprosy prevention are contact tracing and BCG vaccination of infants. Future options may include chemoprophylaxis and early diagnosis of subclinical infections. This study compared the predicted trends in leprosy case detection of future intervention strategies. Methods Seven leprosy intervention scenarios were investigated with a microsimulation model (SIMCOLEP) to predict future leprosy trends. The baseline scenario consisted of passive case detection, multidrug therapy, contact tracing, and BCG vaccination of infants. The other six scenarios were modifications of the baseline, as follows: no contact tracing; with chemoprophylaxis; with early diagnosis of subclinical infections; replacement of the BCG vaccine with a new tuberculosis vaccine ineffective against Mycobacterium leprae (“no BCG”); no BCG with chemoprophylaxis; and no BCG with early diagnosis. Findings Without contact tracing, the model predicted an initial drop in the new case detection rate due to a delay in detecting clinical cases among contacts. Eventually, this scenario would lead to new case detection rates higher than the baseline program. Both chemoprophylaxis and early diagnosis would prevent new cases due to a reduction of the infectious period of subclinical cases by detection and cure of these cases. Also, replacing BCG would increase the new case detection rate of leprosy, but this effect could be offset with either chemoprophylaxis or early diagnosis. Conclusions This study showed that the leprosy incidence would be reduced substantially by good BCG vaccine coverage and the combined strategies of contact tracing, early diagnosis, and treatment of infection and/or chemoprophylaxis among household contacts. To effectively interrupt the transmission of M. leprae, it is crucial to continue developing immuno- and chemoprophylaxis strategies and an effective test for diagnosing subclinical infections. Leprosy is a contagious disease that will remain prevalent, despite the declining number of patients worldwide over the last century. With approximately 250,000 new cases detected annually, leprosy is far from being eradicated. Leprosy can be treated with drugs after disease detection. Some cases can be prevented with a tuberculosis vaccine (BCG) that cross-reacts with the bacterium responsible for leprosy, but this vaccine might be replaced in the future. Furthermore, preventive drugs can reduce the number of new cases among people in contact with infectious patients, but this strategy has not yet become established in common practice. Also, a new test is under development for the detection of infections before the appearance of symptoms. In this study, we used a computer model to assess the effectiveness of seven possible leprosy control activities. Our results showed that the decline in incidence of leprosy would slow down or halt with the introduction of a new tuberculosis vaccine that is ineffective against leprosy. However, this effect could be offset by the implementation of effective tests for early diagnosis or the routine administration of preventative drugs to contacts of patients.
Collapse
Affiliation(s)
- Egil A. J. Fischer
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sake J. de Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - J. Dik F Habbema
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jan Hendrik Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- * E-mail:
| |
Collapse
|
33
|
Al-Mubarak R, Vander Heiden J, Broeckling CD, Balagon M, Brennan PJ, Vissa VD. Serum metabolomics reveals higher levels of polyunsaturated fatty acids in lepromatous leprosy: potential markers for susceptibility and pathogenesis. PLoS Negl Trop Dis 2011; 5:e1303. [PMID: 21909445 PMCID: PMC3167790 DOI: 10.1371/journal.pntd.0001303] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 07/20/2011] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Leprosy is a disease of the skin and peripheral nervous system caused by the obligate intracellular bacterium Mycobacterium leprae. The clinical presentations of leprosy are spectral, with the severity of disease determined by the balance between the cellular and humoral immune response of the host. The exact mechanisms that facilitate disease susceptibility, onset and progression to certain clinical phenotypes are presently unclear. Various studies have examined lipid metabolism in leprosy, but there has been limited work using whole metabolite profiles to distinguish the clinical forms of leprosy. METHODOLOGY AND PRINCIPAL FINDINGS In this study we adopted a metabolomics approach using high mass accuracy ultrahigh pressure liquid chromatography mass spectrometry (UPLC-MS) to investigate the circulatory biomarkers in newly diagnosed untreated leprosy patients. Sera from patients having bacterial indices (BI) below 1 or above 4 were selected, subjected to UPLC-MS, and then analyzed for biomarkers which distinguish the polar presentations of leprosy. We found significant increases in the abundance of certain polyunsaturated fatty acids (PUFAs) and phospholipids in the high-BI patients, when contrasted with the levels in the low-BI patients. In particular, the median values of arachidonic acid (2-fold increase), eicosapentaenoic acid (2.6-fold increase) and docosahexaenoic acid (1.6-fold increase) were found to be greater in the high-BI patients. SIGNIFICANCE Eicosapentaenoic acid and docosahexaenoic acid are known to exert anti-inflammatory properties, while arachidonic acid has been reported to have both pro- and anti-inflammatory activities. The observed increase in the levels of several lipids in high-BI patients may provide novel clues regarding the biological pathways involved in the immunomodulation of leprosy. Furthermore, these results may lead to the discovery of biomarkers that can be used to investigate susceptibility to infection, facilitate early diagnosis and monitor the progression of disease.
Collapse
Affiliation(s)
- Reem Al-Mubarak
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Jason Vander Heiden
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Corey D. Broeckling
- Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, Colorado, United States of America
| | - Marivic Balagon
- Leonard Wood Memorial Center for Leprosy Research, Cebu, Philippines
| | - Patrick J. Brennan
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Varalakshmi D. Vissa
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
- * E-mail:
| |
Collapse
|
34
|
Recent food shortage is associated with leprosy disease in Bangladesh: a case-control study. PLoS Negl Trop Dis 2011; 5:e1029. [PMID: 21572979 PMCID: PMC3091833 DOI: 10.1371/journal.pntd.0001029] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 02/25/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Leprosy is remaining prevalent in the poorest areas of the world. Intensive control programmes with multidrug therapy (MDT) reduced the number of registered cases in these areas, but transmission of Mycobacterium leprae continues in most endemic countries. Socio-economic circumstances are considered to be a major determinant, but uncertainty exists regarding the association between leprosy and poverty. We assessed the association between different socio-economic factors and the risk of acquiring clinical signs of leprosy. METHODS AND FINDINGS We performed a case-control study in two leprosy endemic districts in northwest Bangladesh. Using interviews with structured questionnaires we compared the socio-economic circumstances of recently diagnosed leprosy patients with a control population from a random cluster sample in the same area. Logistic regression was used to compare cases and controls for their wealth score as calculated with an asset index and other socio-economic factors. The study included 90 patients and 199 controls. A recent period of food shortage and not poverty per se was identified as the only socio-economic factor significantly associated with clinical manifestation of leprosy disease (OR 1.79 (1.06-3.02); p = 0.030). A decreasing trend in leprosy prevalence with an increasing socio-economic status as measured with an asset index is apparent, but not statistically significant (test for a trend: OR 0.85 (0.71-1.02); p = 0.083). CONCLUSIONS Recent food shortage is an important poverty related predictor for the clinical manifestation of leprosy disease. Food shortage is seasonal and poverty related in northwest Bangladesh. Targeted nutritional support for high risk groups should be included in leprosy control programmes in endemic areas to reduce risk of disease.
Collapse
|
35
|
Spencer JS, Kim HJ, Wheat WH, Chatterjee D, Balagon MV, Cellona RV, Tan EV, Gelber R, Saunderson P, Duthie MS, Reece ST, Burman W, Belknap R, Mac Kenzie WR, Geluk A, Oskam L, Dockrell HM, Brennan PJ. Analysis of antibody responses to Mycobacterium leprae phenolic glycolipid I, lipoarabinomannan, and recombinant proteins to define disease subtype-specific antigenic profiles in leprosy. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:260-7. [PMID: 21177913 PMCID: PMC3067349 DOI: 10.1128/cvi.00472-10] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 11/24/2010] [Accepted: 12/13/2010] [Indexed: 01/21/2023]
Abstract
A simple serodiagnostic test based on the Mycobacterium leprae-specific phenolic glycolipid I(PGL-I), for individuals with leprosy is nearly universally positive in leprosy patients with high bacillary loads but cannot be used as a stand-alone diagnostic test for the entire spectrum of the disease process. For patients with early infection with no detectable acid-fast bacilli in lesions or with low or no antibody titer to PGL-I, as in those at the tuberculoid end of the disease spectrum, this diagnostic approach has limited usefulness. To identify additional M. leprae antigens that might enhance the serological detection of these individuals, we have examined the reactivity patterns of patient sera to PGL-I, lipoarabinomannan (LAM), and six recombinant M. leprae proteins (ML1877, ML0841, ML2028, ML2038, ML0380, and ML0050) by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). Overall, the responses to ML2028 (Ag85B) and ML2038 (bacterioferritin) were consistently high in both multibacillary and paucibacillary groups and weak or absent in endemic controls, while responses to other antigens showed considerable variability, from strongly positive to completely negative. This analysis has given a clearer understanding of some of the differences in the antibody responses between individuals at opposite ends of the disease spectrum, as well as illustrating the heterogeneity of antibody responses toward protein, carbohydrate, and glycolipid antigens within a clinical group. Correlating these response patterns with a particular disease state could allow for a more critical assessment of the form of disease within the leprosy spectrum and could lead to better patient management.
Collapse
Affiliation(s)
- John S Spencer
- Department of Microbiology, Immunology and Pathology, Colorado State University, Campus Delivery 1682, Fort Collins, CO 80523-1682, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Insight toward early diagnosis of leprosy through analysis of the developing antibody responses of Mycobacterium leprae-infected armadillos. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 18:254-9. [PMID: 21177914 DOI: 10.1128/cvi.00420-10] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Leprosy is a debilitating chronic disease caused by infection with Mycobacterium leprae. A World Health Organization-directed control strategy based upon the identification and treatment of patients has resulted in a marked reduction in the number of registered worldwide leprosy cases over the last 20 years. Despite these efforts, the number of new leprosy cases detected each year now remains relatively stable, and M. leprae infection continues to pose a health problem. It is suggested that earlier diagnosis is required to strengthen control programs. In this study, we have examined the development of antigen-specific immunoglobulin responses within armadillos experimentally infected with M. leprae to identify those responses that develop most rapidly and robustly following infection. Antibody responses to the M. leprae-specific phenolic glycolipid I and several protein antigens previously demonstrated to have diagnostic potential were assessed. Our results identify several antigens that can provide early diagnosis of M. leprae infection but also indicate considerable variability in the development of antigen-specific antibodies. Our data suggest that a combination of antigens is likely required to provide accurate and early leprosy diagnosis.
Collapse
|
37
|
Fischer E, De Vlas S, Meima A, Habbema D, Richardus J. Different mechanisms for heterogeneity in leprosy susceptibility can explain disease clustering within households. PLoS One 2010; 5:e14061. [PMID: 21124916 PMCID: PMC2988824 DOI: 10.1371/journal.pone.0014061] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Accepted: 10/27/2010] [Indexed: 12/03/2022] Open
Abstract
The epidemiology of leprosy is characterized by heterogeneity in susceptibility and clustering of disease within households. We aim to assess the extent to which different mechanisms for heterogeneity in leprosy susceptibility can explain household clustering as observed in a large study among contacts of leprosy patients.We used a microsimulation model, parameterizing it with data from over 20,000 contacts of leprosy patients in Bangladesh. We simulated six mechanisms producing heterogeneity in susceptibility: (1) susceptibility was allocated at random to persons (i.e. no additional mechanism), (2) a household factor, (3, 4) a genetic factor (dominant or recessive), or (5, 6) half a household factor and half genetic. We further assumed that a fraction of 5%, 10%, and 20% of the population was susceptible, leading to a total of 18 scenarios to be fitted to the data. We obtained an acceptable fit for each of the six mechanisms, thereby excluding none of the possible underlying mechanisms for heterogeneity of susceptibility to leprosy. However, the distribution of leprosy among contacts did differ between mechanisms, and predicted trends in the declining leprosy case detection were dependent on the assumed mechanism, with genetic-based susceptibility showing the slowest decline. Clustering of leprosy within households is partially caused by an increased transmission within households independent of the leprosy susceptibility mechanism. Even a large and detailed data set on contacts of leprosy patients could not unequivocally reveal the mechanism most likely responsible for heterogeneity in leprosy susceptibility.
Collapse
Affiliation(s)
- Egil Fischer
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sake De Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Abraham Meima
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Dik Habbema
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jan Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| |
Collapse
|
38
|
Shetty VP. Challenges Facing the Control of Leprosy in the Indian Context. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2010. [DOI: 10.47102/annals-acadmedsg.v39n1p1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
39
|
Rational design and evaluation of a multiepitope chimeric fusion protein with the potential for leprosy diagnosis. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 17:298-303. [PMID: 20016045 DOI: 10.1128/cvi.00400-09] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Despite the reduction in the number of leprosy cases registered worldwide as a result of the widespread use of multidrug therapy, the number of new cases detected each year remains stable in many countries. This indicates that Mycobacterium leprae, the causative agent of leprosy, is still being transmitted and that, without an earlier diagnosis, transmission will continue and infection will remain a health problem. The current means of diagnosis of leprosy is based on the appearance of clinical symptoms, which in many cases occur after significant and irreversible nerve damage has occurred. Our recent work identified several recombinant antigens that are specifically recognized by leprosy patients. The goal of the present study was to produce and validate the reactivity of a chimeric fusion protein that possesses the antibody binding properties of several of these proteins. The availability of such a chimeric fusion protein will simplify future test development and reduce production costs. We first identified the antibody binding regions within our top five antigen candidates by performing enzyme-linked immunosorbent assays with overlapping peptides representing the amino acid sequences of each protein. Having identified these regions, we generated a fusion construct of these components (protein advances diagnostic of leprosy [PADL]) and demonstrated that the PADL protein retains the antibody reactivity of the component antigens. PADL was able to complement a protein that we previously produced (the leprosy IDRI [Infectious Disease Research Institute] diagnostic 1 [LID-1] protein) to permit the improved diagnosis of multibacillary leprosy and that had a good ability to discriminate patients with multibacillary leprosy from control individuals. A serological diagnostic test consisting of these antigens could be applied within leprosy control programs to reduce transmission and to limit the appearance of leprosy-associated disabilities and stigmatizing deformities by directing treatment.
Collapse
|
40
|
From genome-based in silico predictions to ex vivo verification of leprosy diagnosis. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 16:352-9. [PMID: 19176694 DOI: 10.1128/cvi.00414-08] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The detection of hundreds of thousands of new cases of leprosy every year suggests that transmission of Mycobacterium leprae infection still continues. Unfortunately, tools for identification of asymptomatic disease and/or early-stage M. leprae infection (likely sources of transmission) are lacking. The recent identification of M. leprae-unique genes has allowed the analysis of human T-cell responses to novel M. leprae antigens. Antigens with the most-promising diagnostic potential were tested for their ability to induce cytokine secretion by using peripheral blood mononuclear cells from leprosy patients and controls in five different areas where leprosy is endemic; 246 individuals from Brazil, Nepal, Bangladesh, Pakistan, and Ethiopia were analyzed for gamma interferon responses to five recombinant proteins (ML1989, ML1990, ML2283, ML2346, and ML2567) and 22 synthetic peptides. Of these, the M. leprae-unique protein ML1989 was the most frequently recognized and ML2283 the most specific for M. leprae infection/exposure, as only a limited number of tuberculosis patients responded to this antigen. However, all proteins were recognized by a significant number of controls in areas of endemicity. T-cell responses correlated with in vitro response to M. leprae, suggesting that healthy controls in areas where leprosy is endemic are exposed to M. leprae. Importantly, 50% of the healthy household contacts and 59% of the controls in areas of endemicity had no detectable immunoglobulin M antibodies to M. leprae-specific PGL-I but responded in T-cell assays to >or=1 M. leprae protein. T-cell responses specific for leprosy patients and healthy household contacts were observed for ML2283- and ML0126-derived peptides, indicating that M. leprae peptides hold potential as diagnostic tools. Future work should concentrate on the development of a sensitive and field-friendly assay and identification of additional peptides and proteins that can induce M. leprae-specific T-cell responses.
Collapse
|
41
|
Oskam L, Dockrell HM, Brennan PJ, Gillis T, Vissa V, Richardus JH. Molecular methods for distinguishing between relapse and reinfection in leprosy. Trop Med Int Health 2008; 13:1325-6. [DOI: 10.1111/j.1365-3156.2008.02134_1.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
42
|
Fischer E, Pahan D, Chowdhury S, Oskam L, Richardus J. The spatial distribution of leprosy in four villages in Bangladesh: an observational study. BMC Infect Dis 2008; 8:125. [PMID: 18811968 PMCID: PMC2564933 DOI: 10.1186/1471-2334-8-125] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2007] [Accepted: 09/23/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There is a higher case-detection rate for leprosy among spatially proximate contacts such as household members and neighbors. Spatial information regarding the clustering of leprosy can be used to improve intervention strategies. Identifying high-risk areas within villages around known cases can be helpful in finding new cases. METHODS Using geographic information systems, we created digital maps of four villages in a highly endemic area in northwest Bangladesh. The villages were surveyed three times over four years. The spatial pattern of the compounds--a small group of houses--was analyzed, and we looked for spatial clusters of leprosy cases. RESULTS The four villages had a total population of 4,123. There were 14 previously treated patients and we identified 19 new leprosy patients during the observation period. However, we found no spatial clusters with a probability significantly different from the null hypothesis of random occurrence. CONCLUSION Spatial analysis at the microlevel of villages in highly endemic areas does not appear to be useful for identifying clusters of patients. The search for clustering should be extended to a higher aggregation level, such as the subdistrict or regional level. Additionally, in highly endemic areas, it appears to be more effective to target complete villages for contact tracing, rather than narrowly defined contact groups such as households.
Collapse
Affiliation(s)
- Eaj Fischer
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
| | | | | | | | | |
Collapse
|