Policy Evolution and Lessons Learned from China's Efforts to Eliminate Leprosy.

The prevention and treatment of leprosy is a public health and social issue of global concern. China has become the first country in the world to put forward a proposal on the elimination of the harm caused by leprosy. This paper briefly introduces the status of the spread of leprosy in China, and systematically reviews the evolution of policies and measures at different stages of the disease in China, from the serious epidemic of leprosy to the control of the infection, to the basic elimination, and to the elimination of the hazards. On this basis, five main lessons learned from the control and elimination of leprosy in China were also summarized. These provide the basis for promoting the complete global elimination of leprosy and preventing its re-transmission, thereby benefiting all those who still suffer from the scourge of leprosy.

Molecular epidemiological characteristics of Mycobacterium leprae in highly endemic areas of China during the COVID-19 epidemic.

Objectives: The present study analyzed the impact of the COVID-19 pandemic on the prevalence and incidence of new leprosy cases, as well as the diversity, distribution, and temporal transmission of Mycobacterium leprae strains at the county level in leprae-endemic provinces in Southwest China. Methods: A total of 219 new leprosy cases during two periods, 2018-2019 and 2020-2021, were compared. We genetically characterized 83 clinical isolates of M. leprae in Guizhou using variable number tandem repeats (VNTRs) and single nucleotide polymorphisms (SNPs). The obtained genetic profiles and cluster consequences of M. leprae were compared between the two periods. Results: There was an 18.97% decrease in the number of counties and districts reporting cases. Considering the initial months (January-March) of virus emergence, the number of new cases in 2021 increased by 167% compared to 2020. The number of patients with a delay of >12 months before COVID-19 (63.56%) was significantly higher than that during COVID-19 (48.51%). Eighty-one clinical isolates (97.60%) were positive for all 17 VNTR types, whereas two (2.40%) clinical isolates were positive for 16 VNTR types. The (GTA)9, (TA)18, (TTC)21 and (TA)10 loci showed higher polymorphism than the other loci. The VNTR profile of these clinical isolates generated five clusters, among which the counties where the patients were located were adjacent or relatively close to each other. SNP typing revealed that all clinical isolates possessed the single SNP3K. Conclusion: COVID-19 may have a negative/imbalanced impact on the prevention and control measures of leprosy, which could be a considerable fact for official health departments. Isolates formed clusters among counties in Guizhou, indicating that the transmission chain remained during the epidemic and was less influenced by COVID-19 preventative policies.

Spatiotemporal pattern of leprosy in southwest China from 2010 to 2020: an ecological study.

BACKGROUND: Despite many efforts to control leprosy worldwide, it is still a significant public health problem in low- and middle-income regions. It has been endemic in China for thousands of years, and southwest China has the highest leprosy burden in the country. METHODS: This observational study was conducted with all newly detected leprosy cases in southwest China from 2010 to 2020. Data were extracted from the Leprosy Management Information System (LEPMIS) database in China. The Joinpoint model was used to determine the time trends in the study area. Spatial autocorrelation statistics was performed to understand spatial distribution of leprosy cases. Spatial scan statistics was applied to identify significant clusters with high rate. RESULTS: A total of 4801 newly detected leprosy cases were reported in southwest China over 11 years. The temporal trends declined stably. The new case detection rate (NCDR) dropped from 4.38/1,000,000 population in 2010 to 1.25/1,000,000 population in 2020, with an average decrease of 12.24% (95% CI: -14.0 to - 10.5; P < 0.001). Results of global spatial autocorrelation showed that leprosy cases presented clustering distribution in the study area. Most likely clusters were identified during the study period and were frequently located at Yunnan or the border areas between Yunnan and Guizhou Provinces. Secondary clusters were always located in the western counties, the border areas between Yunnan and Sichuan Provinces. CONCLUSIONS: Geographic regions characterized by clusters with high rates were considered as leprosy high-risk areas. The findings of this study could be used to design leprosy control measures and provide indications to strengthen the surveillance of high-risk areas. These areas should be prioritized in the allocation of resources.

Microbial diversity and potential health risks of household municipal solid waste in China: A case study in winter during outbreak of COVID-19.

Microbial (bacteria and fungi) community structures and their distributions in urban household municipal solid waste (HMSW) were characterized in a sampling campaign in 38 cities of China covering 5 climatic zones. All samples were collected from garbage containers in residential communities during the Winter of 2022, from January 11 to 26. A total of 247 bacterial genera belonging to 22 phyla were identified among the samples. Firmicutes (44.3 %), Bacteroidetes (33.77 %) and Proteobacteria (21.54 %) were the top 3 dominant phyla, and Arcicella (33.11 %) and Leuconostoc (21.87 %) were the dominant genera. Meanwhile, 124 fungal genera from 7 fungal phyla were detected. Ascomycota was the most dominant phylum, with an average relative abundance of 77.31 %. Hanseniaspora (24.03 %), Debaryomyces (13.47 %), Candida (12.18) were the top 3 dominant fungal genera. Alpha-diversity analysis showed that the species richness and diversity of bacterial and fungal communities of HMSW samples belonging to different climatic zones did not differ significantly. Nonmetric multidimensional scaling (NMDS) analysis confirmed that climatic had an effect on microbial communities but did not show a significant correlation. In addition, the distribution of microbial community in different samples from the same climate zone varied considerably, suggesting the HMSW source play important role in shaping microbial community composition. Considering that residential HMSW is relatively fresh, we speculates that the original microorganisms residing in different components of HMSW are key influencing factor for the community, while the reshaping force driven by environmental conditions are relatively weak. In addition, the study identified 13 bacterial and 16 fungal pathogens with Pseudomonas putida (0.25 %) and Sclerotinia sclerotiorum (2.12 %) as the most abundant potential pathogenic bacteria and fungi, respectively. These findings provide valuable information for characterizing microbial features and potential risks of HMSW in its management system.

Analysis of misdiagnosed or delayed-diagnosed Leprosy bacillus infection from 1990 to 2020 with a prophet time series prediction in Hubei Province, China.

To analyze the misdiagnosis or delayed diagnosis of leprosy in Hubei Province, China during the past 30 years, which can provide a scientific basis for improving the prevention and treatment of leprosy by proposing targeted intervention measures. A retrospective study was conducted to compile 161 cases of misdiagnosed or delayed diagnosis of leprosy in Hubei Province during 1990 to 2020 from the National Leprosy Prevention and Control Management Information System and the background information of regional leprosy control centers in Hubei Province. Among 161 study subjects, the shortest delay period was 25.30 months for cases aged 15 to 20 years, the longest delay period was 67.09 months for cases aged 51 to 60 years, the shortest delay period was 35.33 months for type TN cases, and the longest delay period was 75.17 months for type I cases. There were 71 cases (44.10%) misdiagnosed, and the top 5 misdiagnosed disease names were rash 23 cases (32.39%). Top 5 misdiagnosed cases were rash 23 (32.39%), rheumatism 10 (14.08%), skin ulceration 9 (12.68%), dermatitis 9 (12.68%), neuritis 9 (12.68%). In the prophet prediction, the overall trend of leprosy misdiagnosis was increasing and within 1 year the number is fluctuant. The training of medical personnel at all levels on leprosy prevention and treatment should be strengthened, and the public awareness of leprosy prevention and treatment should be enhanced.

Follicular mycosis fungoides: Clinicohistopathologic features and outcomes in a series of 12 Chinese cases.

Background Follicular mycosis fungoides is a distinct variant of mycosis fungoides with a broad clinical spectrum. Recently, many studies have indicated that follicular mycosis fungoides should be divided into different subtypes with disparate prognoses. Objective To define the clinicohistopathologic features and outcomes of follicular mycosis fungoides and to identify risk factors that may be related to the prognosis of Chinese patients with follicular mycosis fungoides. Materials and methods We conducted a single-centre retrospective study and reviewed the clinical, histopathologic and immunophenotypic data of 12 patients diagnosed with follicular mycosis fungoides between 2009 and 2020 in the Department of Dermatology of West China Hospital of Sichuan university. Results A total of 12 patients (seven males and five females) with a mean age of 30 ± 14 years (age range 16-55 years) were included. Scalp and face were the most common involved sites (100%). Follicular papules, acneiform lesions, plaques, and nodules, were the main clinical presentations. Histopathological findings were consistent with the classic manifestations of follicular mycosis fungoides, including folliculotropism, perifollicular and intrafollicular lymphocytic infiltrates and mucinous degeneration. Interferon α-1b was the most common treatment. Four patients died of follicular mycosis fungoides in three years. Notably, immunohistochemical analysis revealed a decreased number of CD20+ cells in the deceased patients. Limitations This is a retrospective evaluation with a small number of cases; further prospective studies are warranted to support our inferences. Conclusion Our patients were much younger than in previous studies. The observed difference in this cohort may be explained by race, in addition to the limited number of cases. A decreased number of B cells might be associated with a poor prognosis, and more studies are necessary to discover the role of B cells in follicular mycosis fungoides as well as in mycosis fungoides.

Evolution of anti-malaria policies and measures in P.R. China for achieving and sustaining malaria-free.

Malaria is a major public health threat worldwide, and it was also widely prevalent in the history in China, seriously endangering people's health and affecting socioeconomic development. China was certified malaria elimination in 2021 with unremitting efforts since the founding of the People's Republic of China in 1949. This great achievement has been another milestone in the fight against major infectious diseases following the elimination of smallpox, poliomyelitis, leprosy, filariasis, neonatal tetanus and blinding trachoma in China. This paper briefly introduces the malaria burden dynamics and the corresponding malaria transmission risk stratificantions, as well as systematically reviews the evolution of anti-malaria policies and measures from severe epidemic to elimination in China. Meanwhile, five key lessons in malaria control and elimination in China are also briefly summarized. All of the above provide evidences for promoting global malaria eradication and preventing reestablishment of malaria transmission, finally benefit all individuals still suffering from the scourge of malaria.

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

BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

Epidemiological Characteristics and Factors Associated with Cure of Leprosy in Chongqing, China, from 1949 to 2019.

Chongqing is one of the focuses of leprosy control in China. Although leprosy control in Chongqing has achieved remarkable results over the years, there are also some problems, such as recurrent epidemics and insufficient early detection in some areas. The aim of this study was to analyze the epidemiological characteristics of leprosy in Chongqing, from 1949 to 2019 and explore the potential factors sociated with cure of leprosy to provide a basis for improving leprosy prevention and treatment strategies in Chongqing. Epidemiological indicators such as incidence and prevalence rates were used to evaluate the prevalence of leprosy. The epidemiological characteristics and control situation of leprosy in patients were analyzed using demographic characteristics, diagnosis, and treatment. Survival analysis was conducted to explore factors associated with the cure of leprosy. From 1949 to 2019, 3,703 cases of leprosy were registered in Chongqing. The incidence of leprosy in the city peaked at 0.853/105 in 1960 and remained below 0.100/105 after 2003. The number of high incidence areas decreased significantly, but they were mainly concentrated in the northeast and southeast regions. The early detection rate increased yearly from 1949 to 2019, and the rate of grade 2 disability ranged from 38.2% to 21.7%, with a fluctuating downward trend after 1960. Male, young age, employment as a farmer, delayed diagnosis, and multibacillary leprosy were risk factors for leprosy cure. Chongqing should continue to strengthen leprosy monitoring to improve the early detection of leprosy and focus on sociated risk factors to carry out multiple strategies.

The burden of physical disability among patients with newly detected leprosy in Yunnan, China, 1990-2020: A population-based, cross-sectional survey.

BACKGROUND: Physical disability is the main complication of leprosy. Although understanding the leprosy rate, prevalence, spatiotemporal distribution, and physical nerve characteristic trends is crucial for the implementation of leprosy control programs and identification of remaining challenges, these data are still unclear. We assessed physical disability trends among newly detected leprosy cases over the past 31 years in 129 counties and territories in Yunnan, China. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the data of newly detected leprosy cases from the Leprosy Management Information System in Yunnan, China, from 1990-2020. All available data related to physical disability were analyzed, including demographic characteristics (sex, age, ethnicity, education level); clinical characteristics (diagnosis duration, detection mode, contact history, leprosy reaction, skin lesions, nerve lesions, disability classification); World Health Organization (WHO) leprosy physical disability indicators; and nerve and eyes, hands and feet (EHF) involvement. A total of 10758 newly diagnosed leprosy cases were identified, and 7328 (65.60%), 1179 (10.55%) and 2251 (20.15%) were associated with grade 0, 1, and 2 disability (G0D, G1D, and G2D), respectively. Male sex, older age, Han ethnicity, urban employment, a longer diagnosis duration, a contact history, greater nerve involvement, and tuberculoid-related forms of leprosy were associated with increased prevalence rates of physical disability. The rates of physical disability in newly detected leprosy cases per 1 million population decreased from 5.41, 2.83, and 8.24 in 1990 to 0.29, 0.25, and 0.54 per 1 million population in 2020, with decreases of 94.64%, 91.17%, and 93.44% in G2D, G1D and total physical disability (G1D + G2D) rates, respectively. In the same period, the proportions of G2D, G1D and total physical disability decreased from 28.02%, 14.65%, and 42.67% in 1990 to 10.08%, 11.76%, and 21.85% in 2020, with decreases of 64.03%, 19.73%, and 48.79%, respectively. Nerve thickening was more common than nerve tenderness, and claw hand, plantar insensitivity, and lagophthalmos were the most frequently reported EHF-related disabilities. CONCLUSIONS: Despite general progress in reducing the prevalence of leprosy-related physical disability, the proportion of physical disability among leprosy disease remains high, especially in specific counties. This implies that leprosy cases are being detected at a later stage and that transmission in the community still exists. Further efforts focusing on early detection are crucial for leprosy control and the elimination of the disease burden.

Suspicious symptom monitoring for leprosy: an optimal practice for early detection under a low endemic situation in Zhejiang Province, China.

BACKGROUND: Leprosy is a chronic infectious disease that causes disabilities and deformities. Early detection is a major strategy for leprosy control. This study reported a new practice of suspicious symptom monitoring for early detection of leprosy. METHODS: A descriptive and comparative analysis between a non-strategy group of pre-implementation of suspicious symptom monitoring in 2005-2011 and a strategy group of strategy implementation in 2012-2018 was conducted through indicators of the number of times of misdiagnoses, delayed period, proportion of early detected cases, and proportion of disabilities. RESULT: Compared with the non-strategy group in 2005-2011, the median number of times of misdiagnoses was decreased from two times to zero times (z = 4.387, P < 0.001), and the median delayed period of newly detected cases were shortened from 24 months to 13 months (z = 2.381, P < 0.001), the proportion of early detected cases was increased from 43.7% to 75.2% (χ2 = 29.464, P < 0.001), the proportion of grade 2 disabilities was decreased from 28.6% in the highest year of 2005 to 4.0% in the lowest year of 2014, and the average proportion of disabilities was decreased from 33.5% to 17.6% (χ2 = 9.421, P = 0.002) in the strategy group in 2012-2018, respectively. CONCLUSION: Suspicious symptom monitoring promoted early detection of cases by reducing the number of times misdiagnosis of leprosy patients, shortening the delayed period, increasing the proportion of early detection, and decreasing the proportion of disabilities. It is an important and recommendable public health strategy for leprosy prevention and control in a low epidemic condition.

[The understanding of epidemic diseases in the Qin and Han Dynasties].

In the Qin and Han Dynasties, three views were argued as the main causes of epidemic diseases, the observation of climate, the interaction between nature and humans and 'witchcraft'. Specifically it was thought that abnormal climate, personnel and government decree, and 'gods' and 'ghosts' were responsible for epidemics. This perception led to corresponding countermeasures to deal with epidemic diseases. The abnormal climate in nature was believed to result in the occurrence of epidemic diseases. This was interpreted by traditional Chinese medicine in terms of exogenous diseases. For instance, Huang Di Nei Jing interpreted leprosy with the point of wind-pathogen attacking. Shang Han Lun treated epidemic diseases with the viewpoint of exogenous pathogen. The classic books of Chinese materia medica recorded many cases of preventing and treating epidemic diseases with materia medica. The personnel and government decree refers to the wrong decrees of Emperors and the poor implementation of officials. This was argued to lead to various disasters including epidemic diseases. It was interpreted by Dong Zhongshu, a famous Confucian in the Han Dynasty, as the punishment of gods upon their misconduct. This reminded emperors about reflecting on the epidemic diseases and correcting their mistakes politically. 'Gods' and 'ghosts' were also believed as the cause of epidemics. This idea drove people to deal with epidemic diseases through sacrifices and exorcism.

[Elimination of infectious disease in China, past and future].

In the long history, infectious disease once caused huge disasters to human beings, not only resulting in serious impacts on public health, but even threatening socioeconomic development and national security. Since the founding of the People's Republic of China, China has attached great importance to the prevention and treatment of infectious disease and achieved remarkable achievements. This article mainly summarizes the historical progresses of the eradication of smallpox and the eliminations of polio, leprosy, filariasis, neonatal tetanus, blinding trachoma and malaria in China, and discusses the eliminations of the infectious diseases which can be conducted in the future.

Risk factors for physical disability in patients with leprosy disease in Yunnan, China: Evidence from a retrospective observational study.

BACKGROUND: Leprosy is potentially debilitating. The risk factors related to physical disabilities associated with leprosy disease in Yunnan, China was not clear. METHODOLOGY/PRINCIPAL FINDINGS: We studied 10644 newly detected leprosy patients from Yunnan, China, from 1990 to 2019. Factors associated with Grade 1 (G1D) and Grade 2 (G2D) physical disabilities or overall physical disabilities (combined G1D and G2D) associated with leprosy were analyzed using multinomial and ordinal logistic regression analyses. The following factors were associated with the development of physical disability in these patients with leprosy: delayed diagnosis [odds ratio (OR): 5.652, 4.399, and 2.275; 95% confidence intervals (CIs): 4.516-7.073, 3.714-5.212, and 2.063-2.509; for ≥ 10, 5-10 y, and 2-5 years, respectively], nerve damage (OR: 3.474 and 2.428; 95% CI: 2.843-4.244, and 1.959-3.008; for 2 and 1 damaged nerves, respectively), WHO classification of PB (OR: 1.759; 95% CI: 1.341-2.307), Ridley-Jopling classification (OR: 1.479, 1.438, 1.522 and 1.239; 95% CI: 1.052-2.079, 1.075-1.923, 1.261-1.838, and 1.072-1.431; for TT, BT, BB, and BL when compared with LL, respectively), advanced age (OR: 1.472 and 2.053; 95% CI: 1.106-1.960 and 1.498-2.814; for 15-59 and over 60 years old, respectively), zero skin lesions (OR: 1.916; 95% CI: 1.522-2.413), leprosy reaction (OR: 1.528; 95% CI: 1.195-1.952), rural occupation (OR: 1.364; 95% CI: 1.128-1.650), Han ethnicity (OR: 1.268; 95% CI: 1.159-1.386), and male sex (OR: 1.128; 95% CI: 1.024-1.243). CONCLUSIONS: Delayed diagnosis, nerve damage, no skin lesions, WHO and Ridley-Jopling classifications, leprosy reactions, advanced age, rural occupation, Han ethnicity, and male sex were associated with disability in leprosy patients. Identifying risk factors could help to prevent physical disability.

Presenting symptoms of leprosy at diagnosis: Clinical evidence from a cross-sectional, population-based study.

BACKGROUND: Leprosy is associated with different dermatologic and neurologic manifestations within a wide clinical spectrum, causing a great diagnostic challenge. Therefore, we aimed to examine associations between common presenting symptoms of leprosy and stage at diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: In this cross-sectional study, we analyzed population-level data from the Leprosy Management Information System (LEPMIS) in Yunnan, China, from 2010-2020 and enrolled patients with newly detected leprosy. The data of 2125 newly detected leprosy patients, with 5000 symptoms, were analyzed. Numbness (828/5000, 16.56%), erythema (802/5000, 16.04%), Painless nor pruritic skin lesions (651/5000, 13.02%), eyebrow hair loss (467/5000, 9.34%), and tubercles (442/5000, 8.84%) were common symptoms of leprosy. The symptoms related to skin (1935/2533, 76.39%) and leprosy reaction (279/297, 93.94%) were mainly existed in MB group. While the symptoms related to disability (263/316, 83.49%), clinical feature (38/56, 69.09%), and facial features (19/23, 82.61%) were predominantly presented in delayed diagnostic group. Despite low proportions, formic sensation (99/5000, 1.98%), pain (92/5000, 1.84%), pruritus (56/5000, 1.12%), finger contracture (109/5000, 2.18%), muscle atrophy (71/5000, 1.42%), and motor dysfunction (18/5000, 0.36%) were reported during the diagnosis of leprosy. The proportions of skin, skin and nerve, and nerve symptoms as initial symptoms were 33.25%, 44.95%, and 21.80% and as only symptoms were 28.66%, 57.81%, and 13.91%, respectively. In those with physical disability, nerve symptoms were the most frequent symptoms (57.65% and 65.36% for the initial and only symptoms, respectively) compared with skin and skin and nerve symptoms. In the delayed diagnosis group, nerve symptoms were the most frequent symptoms (15.73% and 17.25%) and were associated with the longest diagnostic intervals (mean±SD: 38.88±46.02 and 40.35±49.36 months for initial and only symptoms, respectively) when compared with skin and skin and nerve symptoms. CONCLUSIONS: Understanding the nature of presenting symptoms and developing symptom awareness campaigns would improve the level of leprosy awareness in the community. As nerve symptoms were related to a higher proportion of physical disability and longer diagnosis interval, we should increase awareness about nerve symptoms. Individuals with nerve symptoms should be considered the target group. Neurology outpatient visits may provide potential screening opportunities, and holding focused training for specialized neurology medical staff would enhance the capacity of the health system to recognize leprosy early.

The state of the leprosy epidemic in Yunnan, China 2011-2020: A spatial and spatiotemporal analysis, highlighting areas for intervention.

BACKGROUND: Despite public health efforts to reduce the leprosy burden in Yunnan, China, leprosy remains an important public health problem in some specific areas. We analyzed the epidemiological characteristics and spatial distribution of leprosy in Yunnan, China, and provide data to guide disease prevention and control efforts. METHODOLOGY/PRINCIPAL FINDINGS: The surveillance data of newly detected leprosy cases in Yunnan, China, during 2011-2020 were extracted from the LEPROSY MANAGEMANT INFORMATION SYSTEM IN CHINA (LEPMIS), and spatial distribution analysis, spatial autocorrelation analysis, and spatiotemporal scanning were performed with ArcGIS 10.6.1, GeoDa 1.8.8, and SaTScan 9.4.3 software, respectively. A total of 1907 newly detected leprosy cases were reported in Yunnan, China, during 2011-2020. The new case detection rate (NCDR) decreased from 0.62 in 2011 to 0.25 in 2020, with an annual incidence of 0.41/100,000 population. The proportions of multibacillary (MB) cases, cases in female patients, cases causing grade 2 physical disability (G2D), and cases in pediatric patients were 67.07%, 33.93%, 17.99%, and 2.83%, respectively. The number of counties with an incidence above 1/100,000 population decreased from 30 in 2011 to 8 in 2020. The Moran's I of leprosy in Yunnan, China, during 2011-2020 ranged from 0.076 to 0.260, indicating the presence of spatial clusters. Local spatial autocorrelation (LSA) analysis showed that high-high cluster areas (hot spots) were mainly distributed in the southeastern, northern, and northwestern regions. Spatiotemporal scanning showed three clusters with high NCDRs. The probably primary clusters, occurring during January 1, 2011-December 31, 2015, covered 11 counties in the southeastern region (RR = 5.046515, LRR = 271.749664, P = 0.000). CONCLUSION: The number of leprosy cases in Yunnan decreased overall, although some high-NCDR regions remained. Geographic information system (GIS) analysis coupled with spatial analysis indicated regions with leprosy clusters. Continuous leprosy prevention and control strategies in Yunnan Province should be established, and interventions in high-risk regions should be prioritized and further strengthened.

Epidemiological Characteristics and Trends of Registered Leprosy Cases in China From 2004 to 2016.

Leprosy is an infectious disease caused by Mycobacterium leprae. China was once one of the countries with severe leprosy epidemics, but its incidence has remained low in recent years. Despite this, there has been no decrease in its incidence more recently, and it is still a public health problem which needs to be controlled. In this study, we analyzed the epidemiological characteristics and trends in the detection rate of new cases of leprosy in China between 2004 and 2016. There were 4,519 cases of leprosy in 28 provinces, municipalities, and autonomous regions between 2004 and 2016, and the total incidence was 0.02815 (per 100,000 individuals) and 21 deaths. The overall incidence of leprosy showed an inverted "V" distribution (i.e., an increase followed by a decrease). Yunnan, Sichuan, Guangdong, Guizhou, and Guangxi were the top five regions with the highest incidence rates, and they accounted for 68.7% of the total cases. There were more male patients than female patients, and peasants accounted for 71.7% of the leprosy cases. The patients with leprosy in China were mainly concentrated in the age-group 15-44 years, as this group accounted for 57.2% of the total cases. The purpose of this study is to explore the epidemiology of leprosy in China. This analysis will be useful for future monitoring of leprosy and establishment of public health measures in China, in keeping with the "Programme for the Elimination of Leprosy in China 2011-2020."

Factors Influencing Leprosy Incidence: A Comprehensive Analysis of Observations in Wenshan of China, Nepal, and Other Global Epidemic Areas.

Leprosy remains endemic in some regions and is a global health concern. However, the possible causes and risk factors of the disease remain unclear. Data in Wenshan, China were collected from the Wenshan Institute of Dermatology (1986-2015); data in Nepal were obtained from the Leprosy Control Division, Department of Health Services, Nepal (2011 to 2015); and data from Indonesia, India, and Brazil were collected from WHO records. We assessed the epidemiological trends of leprosy in Wenshan and compared the features of possible causes and risk factors with those of other countries. We then performed a descriptive and statistical analysis to make our study more purposeful and definitive. A total of 3,376 cases were detected in Wenshan from 1986 to 2015. The overall prevalence rate (PR) of leprosy presented a decreasing trend with a peak (4.9/10,000 population) in 1986. The detection of new leprosy cases was higher in males than in females. Visible deformity increased every year since 2005 with a disability of 34.8% in 2015 among new cases. In Nepal, 2,461 leprosy patients received multi-drug therapy (MDT) in 2015 which corresponded to the PR of 0.89/10,000 population. Geographic latitude and socio-economic situations appeared to be the main causes of leprosy, and the healthcare condition was an important factor associated with leprosy incidence. The introduction of MDT effectively reduced leprosy prevalence worldwide. Wenshan (China), Nepal, and other countries share similarities in various aspects with respect to socio-cultural features, geographical distribution, environmental factors, and economic situation, which may contribute to leprosy being endemic in these areas.

Predictive nomogram for leprosy using genetic and epidemiological risk factors in Southwestern China: Case-control and prospective analyses.

BACKGROUND: There is a high incidence of leprosy among house-contacts compared with the general population. We aimed to establish a predictive model using these genetic factors along with epidemiological factors to predict leprosy risk of leprosy household contacts (HHCs). METHODS: Weighted genetic risk score (wGRS) encompassing genome wide association studies (GWAS) variants and five non-genetic factors were examined in a case-control design associated with leprosy risk including 589 cases and 647 controls from leprosy HHCs. We constructed a risk prediction nomogram and evaluated its performance by concordance index (C-index) and calibration curve. The results were validated using bootstrap resampling with 1000 resamples and a prospective design including 1100 HHCs of leprosy patients. FINDING: The C-index for the risk model was 0·792 (95% confidence interval [CI] 0·768-0·817), and was confirmed to be 0·780 through bootstrapping validation. The calibration curve for the probability of leprosy showed good agreement between the prediction of the nomogram and actual observation. HHCs were then divided into the low-risk group (nomogram score ≤ 81) and the high-risk group (nomogram score > 81). In prospective analysis, 12 of 1100 participants had leprosy during 63 months' follow-up. We generated the nomogram for leprosy in the validation cohort (C-index 0·773 [95%CI 0·658-0·888], sensitivity75·0%, specificity 66·8%). Interpretation The nomogram achieved an effective prediction of leprosy in HHCs. Using the model, the risk of an individual contact developing leprosy can be determined, which can lead to a rational preventive choice for tracing higher-risk leprosy contacts. FUNDING: The ministry of health of China, ministry of science and technology of China, Chinese academy of medical sciences, Jiangsu provincial department of science and technology, Nanjing municipal science and technology bureau.