Transmission Of Leprosy Research Articles

Acid Fast Positivity Rate and Associated Factors of Leprosy in a Tertiary Care Hospital of Northeastern Ethiopia: Its Implication for Evidence-Based Leprosy Prevention and Control.

Leprosy is one of the most common skin neglected tropical diseases in Ethiopia posing social stigma, physical disability, deformity, discrimination, loss of social status, and poor quality of life in families. Hence, evidence-based collaborative inter-sectoral actions should be performed to reduce and eliminate its burden in endemic areas. Thus, the aim of this study was to assess the acid-fast positivity rate and associated factors of leprosy among suspected cases in Northeastern Ethiopia: a cross-sectional study. A cross-sectional study was conducted from September 2022 to March 2023 among 256 leprosy-suspected cases selected using a simple random sampling technique. A semi-structured questionnaire was used to collect socio-demographic, clinical, and predictor variables of leprosy through face-to-face interviews. Skin slit specimens were collected and stained using Ziehl-Neelsen staining technique. STATA 17 was used for analysis. The scale reliability coefficient was checked using Cronbach's α and the goodness-of-fit test of the model was assessed by the Hosmer-Lemshow test. Moreover, bivariable and multivariable logistic regression were computed. Finally, variables with an adjusted odds ratio and their p < 0.05 were taken as statistically significant. The mean ± standard deviation of the age of participants was 43.25 ± 16.35. The overall, prevalence of acid-fast positivity among suspected cases was 19.6% (95% CI: 15.8%, 23.4%). Multivariable logistic regression analysis showed that sex being male (p = 0.045), rural residence (p = 0.047), not eating three times meals frequency (p = 0.014), not eating a balanced diet (p = 0.036), poor personal hygiene (p = 0.028), distant from health facility (p = 0.039), not washing hands usually (p = 0.013), presence of current co-infection (p = 0.002), type of leprosy (p = 0.004), and close contact with leprosy cases (p = 0.003) were more likely to be positive for leprosy. The prevalence of leprosy was remained high. Thus, early detection and treatment are necessary to reduce delayed diagnosis and hidden transmission of leprosy in the community. By addressing the driving factors through evidence-based intervention, we can significantly control the burden of leprosy in the affected communities, and improve their health outcomes and quality of life.

Exploring the dynamics of leprosy transmission with treatment through a fractal–fractional differential model

Leprosy continues to be a significant public health challenge in many parts of the world, necessitating novel approaches to understanding and controlling its transmission. The dynamics of leprosy are examined in this study by means of a caputo fabrizio fractal–fractional differential system model. Leprosy transmission and treatment are complex and non-linear processes that can be captured by fractal–fractional derivatives. The temporal progression of the disease is the primary focus of our mathematical analysis, which evaluates a variety of parameter values, including initial population densities and compartmental transitions. Through simulations, we examine the impact of critical parameters on the severity and spread of diseases, as well as the rates of recovery and treatment. Numerical results of the model offer valuable insights into the impact of these parameters on leprosy dynamics, which is beneficial for public health interventions. The stability analysis of the model identifies supplementary conditions that are necessary for the success of disease control. By incorporating these novel mathematical techniques, we hope to improve our understanding of leprosy transmission and ultimately contribute to more effective control strategies. Based on our findings, additional studies investigating the relation between population density, treatment accessibility, and recovery rates are warranted. We hope that by graphically representing the relationships between these factors, we can draw attention to the possibility of targeted interventions that can reduce the transmission of leprosy. This study provides a strong basis for future studies on infectious disease modeling and aids leprosy-affected communities in developing strategies to mitigate the disease’s impact.

Socio-cultural and Environmental Risk Factors for Leprosy in Jaffna District, Sri Lanka

This study was conducted to determine the socio-cultural and environmental risk factors of leprosy in Jaffna. A case-control study was conducted in dermatology clinic, teaching hospital, Jaffna from July 2015 to July 2016. All 97 cases and 291 controls by systematic sampling were recruited using interviewer-administered questionnaire.The mean age of cases was 41 (SD=21) and control was 48 (SD=20). Of 97 cases, 54.6 %( n=53) males; 99 %( n=96) Tamils; 79.4 %( n=77) Hindus; 60 %( n=59) above secondary education. Of 291 controls, 42.3 %( n=123) were males; 99.3 %( n=289) Tamils; 85.6 % (n=249) Hindus; 78.4 % ( n=225) above secondary education.Socio demographic factors (12 variables), house and environmental factors (11 variables), and behavioral factors (18 variables) were included in bivariate analysis and many were found to be significantly (p&lt;0.05) associated with leprosy. Marital status, displacement, monthly income, presence of BCG scar, firewood as cooking fuel, and hunting reptiles were not found to be associated with leprosy. Multiple logistic regression analysis showed significant association between leprosy and - crowded household [OR4.5, (1.5-13.6)], non-availability of drinking water within 30 minutes walking [OR15.1, (2.3-98.3)], environment with shrub [OR2.9, (1.4-6.1)], exposure to shrub [OR2.7, (1.2-5.9)], exposure to leprosy patient [OR10.6, (4.1-27.5)], exposure to fishing [OR4.5, (1.5- 13.6)], visits to leprosy affected area [OR10.8, (4.7-24.5)] and unavailability of safe water source [OR3.3, (1.2- 9.1)]. In addition to the well-known risk factors environment-related risk factors, especially exposure to jungle/shrubs could play a role in the transmission of leprosy.

Zero Leprosy Strategic Plans: Global and National Level: A Short Communication

Since the launch of multidrug therapy in 1982, the global leprosy situation has undergone significant changes, with the prevalence falling from over 5 million cases in the mid-1980s to &lt;200,000 by the end of 2016. In India, the program reduced the prevalence rate from 57.8/10,000 in 1983 to &lt;1/10,000 by the end of 2005, marking the achievement of the World Health Organizations (WHOs) target of eliminating leprosy as a public health issue. The WHO has recently introduced a new global leprosy plan called “Towards Zero Leprosy” as part of the disease-specific strategies outlined in the WHO's roadmap for neglected tropical diseases (NTDs) 2021–2030. This strategy aims to achieve interruption of leprosy transmission by 2030 and provides a framework for direction, objectives, challenges, and strategic pillars at a global level. In India, a committee of over 80 experts in the field of leprosy developed the National Strategic Plan and Roadmap for Leprosy 2023–2027, which was published on January 30, 2023. This policy is aligned with the WHO's NTDs roadmap 2021–2030 and the Global Leprosy Strategy 2021–2030, both of which aim to interrupt leprosy transmission by 2030. In this article, we have discussed the strategic plans of both the National leprosy eradication programme (NLEP) and the WHO.

Training and Active Case Detection to Prevent Leprosy: Effect on Knowledge, Attitude and Skills of Health Workers on Early Diagnosis of Leprosy in a Leprosy Hotspot District in Ethiopia.

Despite all of the efforts, leprosy continues to affect hundreds of thousands of people every year, including children, showing the ongoing transmission of the disease within the population. The transmission of leprosy can be interrupted through an integrated approach that includes active case-finding, contact tracing and capacity building of health workers. A cross-sectional study design was used to assess the knowledge, attitudes and skills of health workers in the screening and diagnosis of leprosy. One hundred and eighty-one and eighty-eight health care workers participated in the pre-and post-assessment surveys, respectively. Data were collected through interviews and an observational checklist. Frequency tables and graphs were used to describe the study variables, and statistical significance between pre- and post-assessment surveys was declared at p-value < 0.5. The percentages of healthcare workers with good knowledge, positive attitudes and skills were 61.2%, 55.6% and 51.7% in the pre-assessment survey and 77.3%, 56.3% and 75.0%, respectively, in the post-assessment survey. There was a significant improvement in the knowledge and skill scores of participants in the post-assessment survey (p < 0.01). During the campaign, 3780 index contacts were screened; 570 (15.1%) were diagnosed with skin diseases, and 17 new leprosy cases were diagnosed (case detection rate of 45 per 10,000 contacts). Training improved the knowledge and skills of healthcare workers, and a large number of skin diseases were detected through mass screening and active case findings. Providing training for frontline healthcare workers contributed to the detection of more cases and facilitated early detection of leprosy cases.

Leprosy in North India in Post-Elimination Era: A Retrospective Study

Abstract Background: India achieved elimination target for leprosy in December 2005. However, many pockets in the country continue to report significant number of cases. Aim: The aim of the study was to study the profile of leprosy cases presenting to a tertiary care hospital in North India in post-elimination era. Patients and Methods: The study was conducted at Hansen’s disease clinic. The study design was a retrospective observational study. Chart review of treatment naive leprosy patients enrolled between 1st January 2018 and 31st December 2019 was done. Data regarding demographic profile, clinical spectrum of leprosy, slit-skin smears (SSSs) and histopathological findings were analysed. Statistical Analysis: Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) software version 23 (SPSS Inc., Chicago, IL, USA). Data were statistically described in terms of range, mean ± standard deviation, frequency (number of cases), and relative frequency (percentages). Results: Amongst a total of 115 patients, males (68%, n = 79/115) outnumbered females. Children (&lt;15 years) constituted 0.86% cases (n = 1/115) and 26% cases (n = 30/115) were above 50 years of age. Multibacillary leprosy (73%, n = 84/115) was more common. Borderline lepromatous (41.7%, n = 48/115) was the most common clinical type of leprosy, whereas Grade 2 disability was noted amongst 0.05% (n = 6/115) patients at presentation. SSS were positive in 60% (69/115) cases. Conclusions: The present study showed a significant increase in cases in the older age group and decrease in new cases in children. Furthermore, multibacillary cases outnumbered the paucibacillary cases. Similar trends were reported to be an indicator of decreasing incidence of leprosy in countries that eliminated leprosy. We speculate that India may be entering a phase of decreased community transmission of leprosy. Further, multicentric studies across the country may throw more light.

Health Education Method on Leprosy Prevention: Integrative Review.

Leprosy is still found mainly in lower-middle-income countries. Breaking the chain of leprosy transmission requires various ways, especially by increasing knowledge of leprosy prevention through health education. Although several studies have mentioned the effectiveness of health education, there is still uncertainty about the best method to use. Therefore, the review question should be answered: what forms of health education have been developed about Leprosy in the community? This review study complies with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) version 2020. The search for relevant literature involved PubMed, ScienceDirect, ERIC, Cochrane, and ProQuest databases for the studies published in the 2000 to 2023 period with the inclusion criteria such as increasing knowledge, changing attitudes and behavior, and increasing positive stigma. The quality of the study was assessed using the Critical Appraisal Skills Program, and the Risk of Bias using the Cochrane RoB tool. Overall search on databases resulted in a total of 184,681 articles. Only six studies were eligible to be included in this review. Various educational methods were used in the eligible studies, including MH Mobile, the myth or truth on Leprosy game, posters, leaflets, community meetings, tele-education theweb, discussion lists, chats, activity diaries, iconographic 3D videos, classes on video streaming, video conference, case simulation, lecture, and the contact intervention (education, testimonies (direct contact), videos, and comics). All of the methods used had the potential to improve knowledge, attitude, and practice and reduce negative stigma regarding Leprosy. There is no method of health education superior to another on Leprosy prevention.

RELATIONSHIP BETWEEN BCG VACCINATION HISTORY AND THE INCIDENCE OF LEPROSY IN CHILDREN: A LITERATURE REVIEW

Background: Globally, 9,052 new cases of leprosy in children were reported, with a corresponding rate of 4.5 per million child population. Children are believed to be the most vulnerable group to M. leprae infections due to their immature immunity. Purpose: This study aims to determine the relationship between the history of BCG vaccination and leprosy incidence in children. Methods: This study used a literature review method that involved a systematic search. The data sources were obtained using several databases, namely Google Scholar, Proquest, Science Direct, and Pubmed. Keywords were built using the PICOS protocol and Boolean Operators, so the keywords used were "relationship" AND "BCG vaccine" AND "leprosy" AND "children". The research selection and search procedures were explained using the PRISMA 2020 method and research included in this study following the inclusion and exclusion criteria that have been set. Results: There were eight studies suitable for inclusion in this literature review. Five articles concluded that there was a relationship between the history of BCG vaccine and the incidence of leprosy in children, while three articles concluded that there was no relationship between the two variables. Conclusion: The BCG vaccine is useful as an effort to prevent the transmission and spread of leprosy in children. Children who do not receive BCG immunization are more susceptible to leprosy than those who receive immunization. The BCG vaccine has a protective effect to prevent children from contracting and transmitting leprosy to other people.

Comparative evaluation of slit-skin smear with punch biopsy for diagnosing leprosy in suspected patient attending a tertiary care hospital in peripheral West Bengal

Background: Leprosy usually remains underdiagnosed or over-diagnosed due to a high dependency on clinical expertise. Leprosy requires a simple easy-to-perform laboratory test that guides clinicians to come to a conclusion with clinical correlation. Punch biopsy is the gold standard but it requires a biopsy facility in a hospital setting. Molecular diagnosis is out of reach even in resource-rich setups due to the non-availability of commercial kits. In this context slit-skin smear (SSS) might be an easier alternative to guide clinicians for a quality diagnosis, especially in peripheral hospitals. Aims and Objectives: To determine diagnostic sensitivity and specificity of SSS with respect to punch biopsy. Materials and Methods: The present study is an observational cross-sectional study conducted in a teaching institute in peripheral West Bengal. Two samples from clinically suspected patients of leprosy were collected for SSS and punch biopsy. Tests were performed as per standard laboratory protocol. Positive cases were informed to the clinician and treated as per World Health Organization treatment guidelines. SSS was compared to a punch biopsy with respect to sensitivity, specificity, positive predictive value, and negative predictive value. Results: Twenty-five among 59 clinically suspected cases were positive by either two tests or only one test. Twenty-one were males and four were female. Thirty-six was the median age distribution in positive cases 19 cases were positive by both SSS and punch biopsy, five by punch biopsy only, and one by SSS only. Sensitivity and specificity were 79.17% and 97.14%, respectively. Conclusion: SSS is not inferior to punch biopsy even in paucibacillary cases. It is a simple easy-to-perform test but requires training and awareness in medical personnel to make it a front-line weapon to combat continuous leprosy transmission in the community.

Dermatology Photo Quiz 3

Leprosy has been prevalent in India for a very long time. To control the prevalence rate (PR) of leprosy in India, Government of India (GOI) launched “National Leprosy Control Programme (NLCP)” with Dapsone monotherapy in 1955. The PR in 1983 was 57/10000 population. In 1983 GOI launched “National Leprosy Eradication Programme (NLEP)” with "Multi Drug Treatment (MDT)”. PR came down to &lt;1/10000 population in 2005. World Health Organization (WHO) declared leprosy was eliminated from India in 2005. Clinicians all over India are diagnosing leprosy cases and treating them. Multi Bacillary (MB) and Pauci Bacillary (PB) cases are commonly detected. Detection of new cases reminds us that transmission of leprosy is still active in the community. We are reporting a case of leprosy. Keywords: GOI, NLCP, NLEP, MDT, WHO, MB, PB

Ticks are unlikely to play a role in leprosy transmission in the Comoros (East Africa) as they do not harbour M. leprae DNA.

Leprosy, one of the oldest known human diseases, continues to pose a global challenge for disease control due to an incomplete understanding of its transmission pathways. Ticks have been proposed as a potential contributor in leprosy transmission due to their importance as vectors for other infectious diseases. In 2010, a sampling of ticks residing on cattle was conducted on the islands Grande Comore, Anjouan, and Mohéli which constitute the Union of the Comoros where leprosy remains endemic. To investigate the potential role of ticks as a vector in transmission of leprosy disease, molecular analyses were conducted. Out of the 526 ticks analysed, none were found to harbour Mycobacterium leprae DNA, as determined by a quantitative polymerase chain reaction (qPCR) assay targeting a family of dispersed repeats (RLEP) specific to M. leprae. Therefore, our results suggest that in the Union of the Comoros, ticks are an unlikely vector for M. leprae.

Implementation of suitable optimal control strategy through introspection of different delay induced mathematical models for leprosy: A comparative study

AbstractInvolving intracellular delay into a mathematical model and investigating the delayed systems by incorporating optimal control is of great importance to study the cell‐to‐cell interactions of the disease leprosy. Keeping this in mind, we have proposed two different variants of delay‐induced mathematical models with time delay in the process of proliferation of Mycobacterium leprae bacteria from the infected cells and a similar delay to indicate the time‐lag both in the proliferation of M. leprae bacteria and the infection of healthy cells after getting attached with the bacterium. In this research article, we have performed a comparative study between these two delayed systems equipped with optimal control therapeutic approach to determine which one acts better to unravel the complexities of the transmission and dissemination of leprosy into a human body as far as scheduling a perfect drug dose regime depending on this analysis remains our main priority. Our investigations suggest that adopting optimal control strategy consisting of combined drug therapy eliminates the oscillatory behavior of the delayed systems completely. Existence of optimal control solutions are demonstrated in detail. To achieve the optimal control profiles of the drug therapies and to obtain the optimality systems, Pontryagin's Minimum principle with delay in state are employed for our controlled systems. Furthermore, the analytical as well as the numerical outcomes obtained in this research article indicate that the delayed bacterial proliferation and M. leprae‐induced infection model equipped with optimal control policy performs more realistically and accurately in the form of a safe and cost‐effective double‐drug therapeutic regimen. All the mathematical results are verified numerically and the numerical results are compared with some recent clinical data in our article as well.

Specialized active leprosy search strategies in an endemic area of the Brazilian Amazon identifies a hypermutated Mycobacterium leprae strain causing primary drug resistance.

Leprosy, an infectious disease caused by Mycobacterium leprae, remains a public health concern in endemic countries, particularly in Brazil. In this study, we conducted an active surveillance campaign in the hyperendemic city of Castanhal in the northeastern part of the state of Pará using clinical signs and symptoms combined with serological and molecular tools to diagnose new cases and to identify drug resistance of circulating M. leprae strains and their distribution in the community. During an active surveillance of one week, we enrolled 318 individuals using three different strategies to enroll subjects for this study: (i) an active survey of previously treated cases from 2006 to 2016 found in the Brazil National Notifiable Disease Information System database (n = 23) and their healthy household contacts (HHC) (n = 57); (ii) an active survey of school children (SC) from two primary public schools in low-income neighborhoods (n = 178), followed by visits to the houses of these newly diagnosed SC (n = 7) to examine their HHC (n = 34) where we diagnosed additional new cases (n = 6); (iii) and those people who spontaneously presented themselves to our team or the local health center with clinical signs and/or symptoms of leprosy (n = 6) with subsequent follow-up of their HHC when the case was confirmed (n = 20) where we diagnosed two additional cases (n = 2). Individuals received a dermato-neurological examination, 5 ml of peripheral blood was collected to assess the anti-PGL-I titer by ELISA and intradermal earlobe skin scrapings were taken from HHC and cases for amplification of the M. leprae RLEP region by qPCR. Anti-PGL-I positivity was highest in the new leprosy case group (52%) followed by the treated group (40.9%), HHC (40%) and lowest in SC (24.6%). RLEP qPCR from SSS was performed on 124 individuals, 22 in treated cases, 24 in newly diagnosed leprosy cases, and 78 in HHC. We detected 29.0% (36/124) positivity overall in this sample set. The positivity in treated cases was 31.8% (7/22), while in newly diagnosed leprosy cases the number of positives were higher, 45.8% (11/23) and lower in HHC at 23.7% (18/76). Whole genome sequencing of M. leprae from biopsies of three infected individuals from one extended family revealed a hypermutated M. leprae strain in an unusual case of primary drug resistance while the other two strains were drug sensitive. This study represents the extent of leprosy in an active surveillance campaign during a single week in the city of Castanhal, a city that we have previously surveyed several times during the past ten years. Our results indicate the continuing high transmission of leprosy that includes fairly high rates of new cases detected in children indicating recent spread by multiple foci of infection in the community. An unusual case of a hypermutated M. leprae strain in a case of primary drug resistance was discovered. It also revealed a high hidden prevalence of overt disease and subclinical infection that remains a challenge for correct clinical diagnosis by signs and symptoms that may be aided using adjunct laboratory tests, such as RLEP qPCR and anti-PGL-I serology.

Leprosy Classification, Clinical Features, Epidemiology, and Host Immunological Responses: Failure of Eradication in 2023.

Leprosy is of big concern in the medical fraternity. Leprosy is also known as Hansen's disease. It is a curable communicable disease that remains prevalent in most countries all over the globe. It is a chronic granulomatous infection commonly caused by Mycobacterium leprae and Mycobacterium lepromatosis, which mainly show an effect on the skin and peripheral nerves. To control the disease and minimize the impact of the disease, much effort has been put into it for decades. Nearly 0.2 million fresh cases were documented in 2017 worldwide in spite of being declared "eradicated" by the WHO in the year 2000. However, impressive achievements have been made in several countries, including India; still, we are lagging behind the ultimate goal of the final disappearance of leprosy. Extensive migration is a crucial element that may transmit leprosy to unaffected areas. Additionally, there are several areas in the USA where person-to-person leprosy transmission has been reported without a prior history of exposure. Recently, WHO instigated a new Global Leprosy Strategy 2021-2030, termed "Towards Zero Leprosy." In this article, we review the clinical features, leprosy epidemiology, transmission, classification, host immunological response, and diagnostic challenges.

Measurements and Accuracy of IgM and IgG Anti Phenolic Glycolipid-1 Levels in Blood Serum for Early Detection Mycobacterium leprae by using Enzyme-Linked Immunosorbent Assay (ELISA): A Reality of a Laboratory

Indonesia was the third most recent case of leprosy globally in 2020 with 11,173 people, after India and Brazil. Most of the leprosy manifestations are asymptomatic. This is possibly as subclinical leprosy which individuals without leprosy symptoms but have leprosy specific antibodies high levels, so it has the potential to become a transmission and disability. Therefore, an ELISA test need for early detection in preventing leprosy transmission. This study aims to measure IgM and IgG antibody levels in leprosy patients and assess the accuracy of the measurement results. This research is a cross-sectional study. Five patients' blood samples have analyzed for IgM and IgG anti-PGL-1 antibody levels by ELISA. Accuracy interpretation of this measurement based on the %CV. Antibody levels were classified based on the cut-off &lt;605 u/ml as IgM seronegative or &lt;630 u/ml as IgG seronegative, 605–1000 u/ml as low seropositive IgM or 630-1000 u/ml as low seropositive IgG, and &gt;1000 u/ml as high seropositive IgM and IgG. Among five patients examined, 40% had high seropositive leprosy with anti-PGL-1 IgM and IgG antibody titers&gt;1000 u/ml, and 60% of patients had seronegative leprosy. Accuracy in this ELISA test shows high accuracy with %CV &lt;10% in the conversion of OD to antibody titer levels. IgM and IgG Anti PGL-1 antibody titers by ELISA as one of the parameters in identifying patients at higher risk of leprosy. A significant portion of patients with high seropositive leprosy with high accuracy.

Improved leprosy elimination efforts in Somalia, 2015–2021: achievements in a challenging environment and the way forward

Background Since leprosy was eliminated as a public health problem in 2000, trends in case detection have been declining. However, from 2015, case detection in the WHO Eastern Mediterranean (EM) region increased mainly due to reports from Somalia that re-instated the national programme. As Somalia reported 57% of new cases in the EM region in 2021, we reviewed the national control programme activities and the characteristics of reported cases to understand leprosy transmission in the country. Methods From 2012 to 2021, we extracted data from WHO’s Global Health Observatory and the national leprosy control programme’s patient register in Somalia. From 2015 onwards, leprosy cases were detected by the Federal Ministry of Health through mobile teams conducting “skin camps” in 47 districts across seven regions. We analyzed data to describe the overall case detection rate and rates per period, place and person, including severity measured by grade two disability (G2D) and multibacillary (MB) cases. Results The overall case detection rate increased 11-fold between 2012 and 2021, from 6 cases per million in 2012 to 106 cases per million in 2021 in females and from 16 cases per million in 2012 to 132 cases per million in 2021 in males. Case detection among children under 15-years of age also increased from 4 cases per million in 2012 to 13 cases per million in 2021. Initially, the proportion of MB cases and G2D at the time of diagnosis increased from 60% and 11% in 2012 to 87% and 42% in 2015 respectively, when the national programme resumed leprosy control activities. By 2021, the MB proportion decreased to 45% and G2D proportion also decreased to 2%. From 2015 to 2021, four regions in Somalia reported 77% of the new cases and 83% of cases with G2D: Lower Shabelle, Middle Juba, Lower Juba and Middle Shabelle. Conclusion “Skin-camps” for case detection were effective in finding hidden leprosy cases and reducing the delay in diagnosis over time. The constant case detection rate among the female population, equal to the male population, points to sufficient programme reach. However, low disability rates persisted among this population which could be due to continued underlying stigma. Reports of new cases among children suggest ongoing transmission requiring prevention strategies such as single dose rifampicin post-exposure prophylaxis.

High seropositivity against NDO-LID in a group of household contacts of leprosy patients. Are we close to leprosy elimination in Colombia?

ABSTRACT Introduction. Leprosy is a chronic infectious disease caused by two mycobacteria (Mycobacterium leprae and Mycobacterium lepromatosis). The household contacts (HHC) of leprosy index cases are at higher risk of being infected with these mycobacteria. Therefore, serological testing in HHC would be an effective strategy to eliminate leprosy in Colombia. Objective: To determine the seroprevalence and factors associated with the infection by M. leprae in HHC. Methods: An observational study was conducted in 428 HHC located in the Colombian Caribbean, Andean, Pacific, and Amazonian regions. We evaluated the seropositivity and titrations of IgM, IgG, and protein A against NDO-LID. Results: The evaluated HHC showed high seropositivity, precisely 36.9% anti-NDO-LID IgM, 28.3% anti-NDO-LID IgG, and 47.7% protein A. Furthermore, Protein A showed a greater capacity to detect infected individuals than other anti-NDO-LID conjugates (p < 0.0001). This study did not show differences in the seropositivity according to sex or age of the HHC (p > 0.05). Higher seropositivity for IgM was evidenced mainly in HHC located in the Colombian Pacific region (p 0.001). This research did not show differences in the seropositivity for these serological tests between HHC of PB or MB leprosy patients (p > 0.05). Conclusion. Leprosy transmission is still active between Colombian HHC. Consequently, controlling leprosy transmission in this population is fundamental to eradicating this disease.

Serological IgM antibody profile of &lt;i&gt;M. Leprae&lt;/i&gt; PGL-1 and characteristics of leprosy contacts from an endemic area in East Java, Indonesia

Background: Indonesia has the third-highest leprosy prevalence, and the transmission continues. Objectives: the present study aimed to describe some of the characteristics of leprosy contacts, such as the profile of the serological antibody IgM anti-PGL-1, socioeconomic factors, environmental factors, and behavioral factors. Materials and Methods. We conducted a cross-sectional study involving 77 leprosy contacts from an endemic area in Winongan, Pasuruan, East Java, Indonesia. The households or neighbors of the leprosy case recorded at Winongan Health Center, voluntarily participated in this study. Informed consent was obtained before starting the study. Three of them were excluded because they showed skin lesions as leprosy symptoms. Serum samples were assayed for IgM antibodies PGL-1 titers using enzyme-linked immunosorbent assay (ELISA). The questionnaire was used to collect information about demographic, socioeconomic, environmental, and behavioral aspects of contact. The data were analyzed descriptively using Fisher’s Exact Test. Results. Of 74 contacts, all of them were contacts of MB cases, and 6 (8.11%) were seropositive, with a cut-off point ≥ 605 ug/ml. Although none of the contact characteristics were significantly associated with IgM anti-PGL-1 seropositivity, potential risk markers and indirect transmission of leprosy were identified, including 56.76% manual labor, 90.54% living in poverty, 83.78% drinking from unprotected springs, only 20.27% boiling water to drink, and 48.65% bathing in open water bodies. Conclusions. The seropositivity among contacts, especially perimeter contacts, may identify potential active infection and transmission of leprosy in this population. Identified potential risk markers of leprosy should be noticed for prevention programs supporting leprosy elimination.

Genotyping of Mycobacterium leprae strains in south central coast and central highlands of Vietnam.

Leprosy remains an important health problem worldwide. It is one of the oldest recorded diseases of humankind. In this study, we expanded the analysis of the geographic distribution of Mycobacterium leprae by investigating SNPs and rpoT genotypes in South Central Coast and Central Highlands clinical isolates, providing insights into the distribution and transmission of leprosy in Vietnam and in this geographic region. 27 clinical isolates from the patients, determined the genotypes of M. leprae by SNP and rpoT polymorphism. SNP genotyping was performed by PCR amplification and sequencing, rpoT genotyping by PCR amplification and electrophoresis. All of 27 DNA samples (100%) were positive with RLEP TaqMan PCR (Ct value range is 18-32 on 3 replicates). SNP type 1 was identified in 15 isolates (56%), while SNP type 3 was detected in 12 samples (44%). SNP type 2 and type 4, were not detected. The 6-base repeat region of the rpoT gene was amplified by PCR and analyzed by 4% MetaPhor™ agarose gel electrophoresis. All isolates yielded amplification products of 91-bp, but not 97-bp. This study showed that 56% of isolates belonged to type 1, 44% to type 3. In addition, all samples have the 3-copy hexamer genotype in the rpoT gene.

Leprosy among new child cases in China: Epidemiological and clinical analysis from 2011 to 2020.

Leprosy, caused by Mycobacterium leprae infection, mainly affects skin and peripheral nerves and may further lead to disability and deformity if not treated timely. The new case detection rate of leprosy in children reflects the active transmission of leprosy infection. This study aims to present the epidemiology and clinical characteristics of new leprosy cases in children in China from 2011 to 2020. All data from leprosy patients younger than 15 years old were extracted from the Leprosy Management Information System in China (LEPMIS). Statistical Package for the Social Sciences (SPSS) version 12.0 was used for descriptive and analytical statistics of the epidemiological and clinical indicators by the Mann-Whitney test, Kruskal-Wallis test, and Fisher's exact test. And geographical distribution was analyzed by ArcGIS 10.5. A total of 152 pediatric new cases of leprosy were found over the last decade. The new case detection rate of pediatric leprosy cases decreased from 0.13 to 0.02 per 1,000,000 population over the last ten years. New pediatric cases had a higher new case detection rate in Guizhou, Sichuan, and Yunnan Provinces. All but 7 provinces in China achieved zero new child case for consecutive five years. The onset of leprosy peaked between 10 and 14 years of age, and the male to female ratio was 1.71:1. Pediatric patients were predominantly infected from symptomatic household adult contacts HHCs. Multibacillary leprosy (MB) was the most common. However, a low proportion of patients developed leprosy reaction and grade 2 disability. The new case detection rate of pediatric leprosy cases has decreased over the past ten years in China. Spatial analysis indicated clusters in high-endemic areas. Leprosy transmission has stopped in the majority of provinces in China. However, sporadic cases may continue to exist for a long time. Active surveillance especially contact tracing should be focused on in future plan for management of leprosy, and interventions in leprosy clusters should be prioritized.