Elimination of lymphatic filariasis:Where do we stand so far?

Lymphatic filariasis(LF),an asymptomatic,acute,and chronic condition in human beings,is the second most common vector-borne disease after malaria.According to the World Health Organization,there are 120 million LF cases detected in 81 tropical and subtropical countries,and one billion people are at risk.Therefore,the Global Program to Eliminate Lymphatic Filariasis was launched in 2000,with the primary objective of stopping LF transmission among all at-risk groups using mass drug administration(MDA),managing morbidities,and preventing LF-related impairments using a minimum treatment package.Additionally,other programs such as epidemiological assessment including National Filaria Control Program and World Health Organization recommended routine and pre-MDA microfilaremia surveys also implemented to stop the LF transmission.The routine filaria surveys were also carried out in around 2000-4000 individuals/month throughout the year whereas pre-MDA surveys were also conducted every year in approximately 4000 individuals in four fixed and four random sites.Furthermore,the Transmission Assessment Survey was also conducted to check the risk of LF among primary school children.Moreover,potential diagnostic methods,systematic surveillance regimes,the Direct Network Report system,and regular trainings and awareness may be also effective in preventing the recurrence of LF.Hence,this review emphasizes the potential advocacy tools and various strategies as well as procedures for monitoring,which could be impactful in eliminating LF.

Elimination of lymphatic filariasis-Challenging but not impossible

We recently went through your article titled“Elimination of lymphatic filariasis:Where do we stand so far?”by Aashna Sinha et al[1].The authors have brought about relevant information regarding lymphatic filariasis focussing on history,diagnostic aspects,treatment strategies and various control measures.Lymphatic filariasis is a neglected parasitic infection affecting millions of people worldwide.

Expression and Evaluation of Wb-SXP-1 and Wb-123 Recombinant Antigens as Potential Diagnostic Biomarkers for Lymphatic Filariasis

Lymphatic filariasis (LF) remains a public health concern as it can cause permanent morbidity and disability to those infected. While the global elimination of LF in these endemic areas is ongoing through mass drug administration, there is the need to develop diagnostic tools that would be utilized to track the progress of total global eradication as well as perform surveillance for the recurrence of lymphatic filariasis transmission. Currently, approved LF diagnosis tools are faced with lack of specificity, low sensitivity, and periodicity dependence. Recombinant filarial antigen-based assays can address these drawbacks and offer practical instruments for LF diagnosis and surveillance. This present study, evaluated rWb-SXP-1 and rWb-123 antigens as potential diagnostic biomarker tools for Wuchereria banchrofti in human sera using microspheres-based multiplex serological assay. Based on statistical analysis using XLSTAT 2019 (Addinsoft) on data generated from multiplex technology assay, generated ROC curves for both rWb-SXP-1 and rWb-123 demonstrated 87.1% sensitivity to Wuchereria banchrofti human sera with rWb-SXP-1 antigens having the highest specificity of 96%. Indication that rWb-SXP-1 and rWb-123 antigens are capable of detecting immunoglobulin G4 (IgG4) antibodies in human sera synthesized specifically against W. banchrofti infections. Therefore, rWb-SXP-1 and rWb-123 antigens can be utilized to detect W. banchrofti infections by antibody profiling with excellent diagnostic sensitivity and specificity using microsphere-based multiplex serological tests. This method can be particularly practical for screening a large number of sera samples and/or for quick, extensive field-testing due to the high-throughput and quick formats applied.

A review of neglected tropical diseases:filariasis

Filariasis is result of parasitic infection caused by three specific kinds of round worm.Lymphatic filariasis is found in under developed region of South America,Central Africa,pacific and Caribbian.It has been found for centuries,with main symptoms as elephant like swelling of the arms,legs and genitals.It is estimate that 120 millions peoples in the world have lymphatic filariasis.The spread of diseases and the challenge encountered in its management are discussed along with a review on drugs against filariasis in this article.Detail on clinical effect of drugs on the infection,safety profile,status in clinical practices and drug resistances are also covered.

Lymphatic filariasis in the foothill areas around Susunia of West Bengal in India

Objective:To investigate the filarial epidemiology in 16 foothill villages around Susunia hill,Bankura district, West Bengal,India.Indices studied were microfilaria rate,mean microfilarial density,filarial disease rate and endemicity rate.Other indices related to transmission were incrimination of vector species,man-hour density of the vector,vector infection and infectivity rates,human blood index of the vector etc.Methods:Examination of 20μL night blood samples by finger prick and clinical examination for filarial diseases of 3 737 people(2 241 male and 1 496 female) was done randomly covering nearly 22%population of the study area.Aspects related to vectors were dealt by regular collection and dissection of mosquitoes.Results:Overall microfilaria rate,mean microfilarial density,disease rate and endemicity rate were 6.10%,10.86%,20.20%and 25.58%,respectively. Causative parasite was identified as Wuchereria bancrofii and Culex quinquefasciatus was incriminated as the vector therein.Vector infection rate,infectivity rate and human blood index were assessed to be 6. 31%,1.38%and 77.33%,respectively.Conclusion:Present study is highly endemic for bancroftian filariasis. More than one fourth of the population under study were filarial victims indicating an overall alarming situation and immediate measure should be taken to rectify the situation.

Historic accounts of Mansonella parasitaemias in the South Pacific and their relevance to lymphatic filariasis elimination efforts today

There are two species of filarial parasites with sheathless microfilariae known to commonly cause parasitaemias in humans:Mansonella perstans and Mtinsonella ozzardi.In most contemporary accounts of the distribution of these parasites,neither is usually considered to occur anywhere in the Eastern Hemisphere.However,Sir Patrick Manson,who first described both parasite species,recorded the existence of sheathless sharp-tailed Mansonella ozzardilike parasites occurring in the blood of natives from New Guinea in each and every version of his manual for tropical disease that he wrote before his death in 1922.Manson's reports were based on his own identifications and were made from at least two independent blood sample collections that were taken from the island.Pacific region Mansonella perstans parasitaemias were also later(in 1923) reported to occur in New Guinea and once before this(in 1905) in Fiji.Although Mansonella-parasilaernias are generally regarded as benign,they are thought to be of public health importance because they can affect the epidemiological monitoring of other filarial diseases.In this article,we reviewed the historic literature concerning Pacific-origin Mansonella-parasitaemias in an attempt to explain how,despite repeated reports of Pacificregion Mansonella-parasilaemias,by as early as the 1970 s,the WHO had arrived at the presentday view that Wuchereria bancrofti is the only cause of filarial parasitaemias in Papua New Guinea.We have also evaluated the evidence supporting the contemporary existence of Pacificarea parasitaemia-causing Mansonella parasites and assessed the relevance such parasites could have for present-day lymphatic filariasis elimination efforts in the region.

A qualitative study on the adverse reactions of mass treatment for lymphatic filariasis in Orissa,India

Objective:To describe the perceptions of community members and programme partners regarding severity,management and impact of adverse reactions on mass drug administration (MDA) compliance.Methods:Based on various qualitative data collected from five districts of Orissa,India,where MDA had been implemented during 2002 and 2004.The qualitative surveys included focus group discussions with community members and health workers,and semi-structured interviews with key informants in the community,medical officers at primary health centres,district level health officers and private practitioners.Results:It showed that many people suffered from adverse reactions,though the reactions were not serious.The paper reported different ways of management of adverse reactions at the community level.The impact of adverse reactions on MDA compliance was serious,as many people did not consume the drug due to fear of adverse reactions.The rumours of adverse reactions and news in media deterred people from consuming the tablets.Conclusion:All categories of respondents indicates the need of more information to address the problem of adverse reactions during MDA.The present paper warrants incorporating the messages on adverse reactions during health communication and social mobilization campaigns of MDA.

Immunological characterization of recombinant Wuchereria bancrofti cuticular collagen(COL-4)as putative vaccine candidate for human lymphatic filariasis

Objective:To elucidate immunoprophylactic potential of recombinant Wuchereria bancrofti(W.bancrofti)cuticular collagen(COL-4)in BALB/c mice and filarial clinical samples.Methods:col-4 gene was PCR amplified from W.bancrofti L3 cDNA library and cloned in pRSET B vector.Recombinant COL-4 was over expressed in salt inducible system and was purified by nickel afiinity chromatography.Humoral and cellular responses were measured by EUSA and peripheral blood mononuclear cells(PBMC)of various filarial clinical samples respectively using purified recombinant COL-4 antigen.Then the protective immune responses of COL-4 immunized BALB/c mice were characterized.Results:Sequence analysis of COL-4 with human host proteins reveals lack of homology.The recombinant COL-4 was found to be at 15 kDa fusion protein.The affinity purified COL-4 showed significant reactivity with putatively immune sere and in a similar fashion it demonstrated marked proliferation in PBMC samples.Immunization studies in experimental filarial host(mice)elicited significant liters with protective antibody isotype profile(IgM and IgG).Cellular immune responses were also significant in terms of splenocytes proliferation assay on mice samples.Conclusions:Our immunological findings in experimental host suggest Th2mediated immune response.Hence,we propose that W.bancrofti COL-4 could be an efficacious vaccine candidate against lymphatic filariasis.

Filariasis presenting as a scrotal nodule in a 2 year old child:A case report

A two year old boy from southwestern village of India presented with a 2 cm×1 cm size swelling in scrotum for 8 months.It was excised surgically and the histopathological examination revealed a gravid filarial worm.The occurrence of adult filarial worm in 2 year old boy signifies the endemicity and high larval load of insect vectors in western coast of south India.

Worm under the Skin—An Unusal Case of Filariasis

Background: Filarial disease has a very high prevalence in South East Asian region especially India. It commonly presents as an affliction of the lymphatic system like acute lymphangitis and chronic lymphedema. Presentation of lymphatic filariasis as a subcutaneous nodule is a rare but previously reported scenario. Aim: We discuss a case with incidental detection of filaria in a subcutaneous nodule following excision biopsy. Case Presentation: 20-year-old male patient presented with subcutaneous swelling in left lower chest. Undergoing excision biopsy for same and on histopathological examination was found to be an encysted filarial worm. Conclusion: Such rare presentation of filariasis has been reported earlier also and should be kept in mind.

Scrotal Filariasis, the Importance of Filarial Dance Sign in Scrotal Ultrasound

Objective: To study the value of the filarial dance sign as a diagnostic sign in scrotal ultrasonography in human Bancroftian filariasis. Methods: We studied 3 patients with scrotal pain, with high-resolution ultrasonography (HRUS) of scrotum including power and color Doppler study. All patients underwent peripheral blood smear. Results: Multiple cystic spaces containing motile echogenic twisted tubular structures were observed in the 3 patients. Peripheral blood smears in the 3 patients confirmed the presence of microfilaria. Mild hydrocele in two patients. Conclusions: HRUS is a useful technique for diagnosing scrotal filariasis in symptomatic patients and is very useful in the follow-up treatment.

Evaluation of Mass Drug Administration Impact on Transmission of Lymphatic Filariasis in 13 Sanitary Districts in Burkina Faso

Introduction: Lymphatic filariasis (LF) is one of the neglected tropical diseases targeted for elimination as a public health issue in the world by 2020. To achieve this goal, one of the strategies is interruption of transmission using chemotherapy (mass drug administration). Burkina Faso in west Africa, an endemic country, has endorsed this resolution. In 2000, all Sanitary Districts (SD) in the country were endemic, and then a national elimination program has made it possible to stop mass treatment in 45 out of 70 SD over 12 years. Sixteen years later, 13 other SD were reeligible for Transmission Assessment Surveys (TAS). This study aimed to determine the current level of the Mass drugs Administration (MDA) impact indicators in these 13 targeted SD in order to decide whether we need to continue MDA. Method: It was a descriptive study that took place from June to September 2017 in 13 SD regrouped into 7 Evaluation Units (EU). The population of the study was 6 to 7 years old children. The community-based cluster survey method was used. The diagnostic test used to detect Wuchereria bancrofti’s circulating antigen (W. bancrofti) is the Filariasis Test Strip (FTS). The critical threshold of positivity was set at 18 positive subjects per EU. Results: We sampled a total of 12,060 children, 48.9% were female and 51.1% male. In the 7 EU, 13 children were positive to W. bancrofti test. The average antigenic prevalence was 0.11% (13/12,060). In all EU, the number of positive subjects was below the critical threshold. Conclusion: At the end of this evaluation of the transmission of lymphatic filariasis in 13 SD of Burkina Faso, we can tell the MDA could be stopped in these areas without risk of resurgence of the disease, according to the current recommendations of WHO. This can be possible by setting up post-TMM surveillance, considering migratory flows, and including villages where positive cases were found to search possible residual transmission zones.

Understanding gender and its intersection with social stratifiers on prevention and care seeking behavior of lymphatic filariasis in Nepal

BackgroundLymphatic filariasis (LF) is a debilitating and painful neglected tropical disease and is one of the leading causes of permanent disability. In many countries, the intersection of gender with various social stratifiers has influenced exposure to LF and ultimately impacting the disease burden and its elimination. This study aimed to explore the influence of gender and its intersection with other social stratifiers for the prevention and care seeking behavior of LF in Nepal.MethodsThis study employed qualitative research methods: in-depth interviews (IDIs) and focus group discussions (FGDs) for data collection in Bardiya, Nepal. A total of 22 IDIs (11 male, 11 female) and 2 FGDs (1 male and 1 female) were conducted with the community people between January and March 2020. The participants were purposively selected to represent different social stratifiers including age, sex, ethnicity, occupation. The data collected were analyzed using a thematic framework approach with use of intersectional gender analysis matrix.ResultsThe study findings revealed that men spend more time outside their household compared to women while fulfilling their roles and responsibilities, largely determined by societal expectations and gender norms. This resulted in limited access to preventive health services for men, as they often missed annual mass drug administration programme in their community and limited access to preventive methods. Further traditional occupation, specific to particular ethnicity, influenced the vulnerability to LF for certain ethnic groups. The ability to prevent exposure varied among individuals. Although women made decisions regarding the use of protective methods, it was influenced by patriarchal and gender norms. They often felt a responsibility to take care and priorities males and other family members when resources are limited. The intersectionality of gender with other social stratifiers such as marital status, ethnicity, and geographical areas influenced individual’s ability to access information related to LF and care seeking.ConclusionsOverall, the findings emphasized how access to resources, division of work, norms and values and decision-making power alone and its interaction with various social stratifiers shaped peoples’ vulnerability to disease, ability to prevent exposure and response to illness.

Five years of post-validation surveillance of lymphatic filariasis in Thailand

Background The World Health Organization (WHO) validated Thailand in 2017 as having eliminated lymphatic filariasis (LF) as a public health problem with recommendations for continued surveillance. This article describes measures and progress made in Thailand with post-validation surveillance (PVS) of LF from 2018 until 2022.Methods The implementation unit (IU) is a sub-village in 11 former LF endemic provinces. Human blood surveys are targeted in 10% of IUs each year. InWuchereria bancrofti areas, filaria antigen test strips (FTS) are used, and inBrugia malayi areas, antibody test kits (Filaria DIAG RAPID) are used. Positive cases are confirmed by thick blood film (TBF) and polymerase chain reaction (PCR). Vector surveys for mosquito species identification and dissection for microfilaria (Mf)/filarial larvae are done in 1% of IUs where human blood surveys are conducted. Human blood surveys using FTS are conducted among migrants in five provinces. Surveillance of cats is done in areas that previously recorded > 1.0% Mf rate among cats. Morbidity management and disability prevention (MMDP) are done every 2 years in LF-endemic areas where chronic disease patients reside.Results From 2018 to 2022, in a total of 357 IUs in 11 provinces, human blood surveys were conducted in 145 IUs (41%) with an average population coverage of 81%. A total of 22,468 FTS and 27,741 FilariaDIAG RAPID were performed. 27 cases were detected: 3 cases ofW. bancrofti in Kanchanaburi province and 24 cases ofB. malayi in Narathiwat province. 4 cases ofW. bancrofti were detected in two provinces through routine public health surveillance. Vector surveys in 47 IUs detectedB. malayi Mf filarial larvae only in Narathiwat province. Chronic LF patients reduced from 114 in 2017 to 76 in 2022. Surveys among 7633 unregistered migrants yielded 12 cases ofW. bancrofti. Mf rate among cats in Narathiwat province declined from 1.9% in 2018 to 0.7% in 2022. MMDP assessments revealed gaps in healthcare provider’s management of chronic cases due to staff turnover.Conclusions In 2022, after 5 years of PVS, Thailand re-surveyed 41% of its previously endemic IUs and demonstrated ongoing transmission in only one province of Narathiwat, where Mf prevalence is below the WHO provisional transmission threshold of 1%. This study highlights the importance of continued disease surveillance measures and vigilance among health care providers in LF receptive areas.

The burden of mental health in lymphatic filariasis

Background:Neglected Tropical Diseases(NTDs)afflict around one billion individuals in the poorest parts of the world with many more at risk.Lymphatic filariasis is one of the most prevalent of the infections and causes significant morbidity in those who suffer the clinical conditions,particularly lymphedema and hydrocele.Depressive illness has been recognised as a prevalent disability in those with the disease because of the stigmatising nature of the condition.No estimates of the burden of depressive illness of any neglected tropical disease have been undertaken to date despite the recognition that such diseases have major consequences for mental health not only for patients but also their caregivers.Methods:We developed a mathematical model to calculate the burden of Disability-Adjusted Life Years(DALY)attributable to depressive illness in lymphatic filariasis and that of their caregivers using standard methods for calculating DALYs.Estimates of numbers with clinical disease was based on published estimates in 2012 and the numbers with depressive illness from the available literature.Results:We calculated that the burden of depressive illness in filariasis patients was 5.09 million disability-adjusted life years(DALYs)and 229,537 DALYs attributable to their caregivers.These figures are around twice that of 2.78 million DALYs attributed to filariasis by the Global Burden of Disease study of 2010.Conclusions:Lymphatic filariasis and other neglected tropical diseases,notably Buruli Ulcer,cutaneous leishmaniasis,leprosy,yaws,onchocerciasis and trachoma cause significant co morbidity associated with mental illness in patients.Studies to assess the prevalence of the burden of this co-morbidity should be incorporated into any future assessment of the Global Burden of neglected tropical diseases.The prevalence of depressive illness in caregivers who support those who suffer from these conditions is required.Such assessments are critical for neglected tropical diseases which have such a huge global prevalence and thus will contribute a significant burden of co-morbidity attributable to mental illness.

The history of the elimination of lymphatic filariasis in China

China used to be one of the most heavily endemic countries for lymphatic filariasis(LF)in the world.There were 864 endemic counties/cities in 16 provinces/autonomous regions/municipalities(P/A/M)with a total population of 330 million at risk of infection.Since the founding of the People’s Republic of China in 1949,the Chinese Government has designated the control of the disease to be a top priority.Due to decades of sustained efforts,close cooperation related to LF control among government departments,and active participation of endemic populations,an all-round campaign for prevention and control has been carried out vigorously and successfully.Over many years,great achievements have been made through persistent endeavors of Chinese scientists and disease control workers.The ultimate goal to eliminate LF in the country was achieved in 2006.

Lessons from lymphatic filariasis elimination and the challenges of post-elimination surveillance in China

Background:The Global Programme to Eliminate Lymphatic Filariasis(GPELF)was launched in response to the call proposed at the 50th World Health Assembly.The goal of the GPELF is to ensure that all the countries where the disease is endemic would have been transmission-free or would have entered post-intervention mass drug administration(MDA)surveillance by 2020.However,several countries are still not on track to discontinue MDA as planned.Thus,issues remain regarding the achievement of stated goals and how to effectively monitor the disease in the post-control and post-elimination phases.Main text:China was once a lymphatic filariasis(LF)endemic country with heavy disease burden.There were three milestones in the LF control phase of China,including:the proposal that the major focus of the control strategy should be on infectious sources;the three regimens of diethylcarbamazine(DEC)administration according to LF endemic extent;and the establishment of the threshold for LF transmission interruption.It has been ten years since China entered the post-elimination stage(declaration of LF elimination in China was in 2007).Two schemes and a diagnostic criterion were issued to guide all levels of disease control and prevention workers that conduct LF surveillance,as well as those caring for chronic filariasis patients.Regular training courses are held to maintain LF control skills in grass-root institutions.The Notifiable Diseases Reporting System,which included LF in 2004,plays an important role in LF post-elimination surveillance.Until now,no resurgence of LF cases has been detected,except for LF residue foci being found in Fuchuan County of the Guangxi Zhuang Autonomous Region.To confirm that transmission is no longer achievable after a decade since the declaration of LF elimination in China,it is expected within the next two years a transmission assessment survey,conducted in previous LF-endemic areas.Conclusions:DEC-fortified salt can help accelerate the progress of GPELF before the sprite phase.Sophisticated diagnostic criteria,systematic surveillance regimes,the Direct Network Report system,and regular trainings can effectively prevent the recrudescence of LF during surveillance phases.

Prevalence of and risk factors for malaria,filariasis,and intestinal parasites as single infections or co-infections in different settlements of Gabon,Central Africa

Background:Malaria,filariasis,and intestinal parasitic infections(IPIs)are common and frequently overlap in developing countries.The prevalence and predictors of these infections were investigated in three different settlements(rural,semi-urban,and urban)of Gabon.Methods:During cross-sectional surveys performed from September 2013 to June 2014,451 individuals were interviewed.In addition,blood and stool samples were analysed for the presence of Plasmodium,filarial roundworm,intestinal protozoan,and helminth infections.Results:Intestinal parasitic infections(61.1%),including intestinal protozoa(56.7%)and soil-transmitted helminths(STHs)(22.2%),predominated,whereas Plasmodium falciparum(18.8%),Loa loa(4.7%),and Mansonella perstans(1.1%)were less prevalent.Filariasis and STHs were mainly found in rural settlements,whereas a higher plasmodial infection prevalence rate was observed in the periurban area.The most common IPI was blastocystosis(48.6%),followed by ascaridiasis(13.7%),trichuriasis(11.8%),amoebiasis(9.3%),giardiasis(4.8%),and strongyloidiasis(3.7%).Hookworm was detected in one adult from rural Dienga.Adults had a higher prevalence of Blastocystis hominis and STHs,whereas Giardia duodenalis was more frequently observed among children aged below 5 years(P<0.01).The polyparasitism rate was 41.5%,with 7.0%Plasmodium-IPIs and 1.8%Plasmodium-STH co-infections.The multivariate analysis showed that living in a suburban area,belonging to the age group of 5-15 years,having none or a secondary education,or having an open body water close to home were significant risk factors for malaria(P≤0.01).For STH infections,identified risk factors were drinking untreated water and living in a rural area(P≤0.04).No significant predictors were identified for IPIs and malaria-IPI co-infection.Conclusions:This study reports a high prevalence of IPIs and intestinal protozoa,but a low rate of malaria-IPI co-infections in the study sites.Improvements in the living conditions of the population such as adequate water supply and proper health education and sanitation should be integrated into control strategies for malaria,STHs,and IPIs.

Lymphatic filariasis, infection status in Culex quinquefasciatus and Anopheles species after six rounds of mass drug administration in Masasi District, Tanzania

Background:Lymphatic filariasis(LF)elimination program in Tanzania started in 2000 in response to the Global program for the elimination of LF by 2020.Evidence shows a persistent LF transmission despite more than a decade of mass drug administration(MDA).It is advocated that,regular monitoring should be conducted in endemic areas to evaluate the progress towards elimination and detect resurgence of the disease timely.This study was therefore designed to assess the status of Wuchererio bancrofti infection in Culex quinqefasciatus and Anopheles species after six rounds of MDA in Masasi District,South Eastern Tanzania.

Mapping and modelling the impact of mass drug adminstration on filariasis prevalence in Myanmar

Background:Lymphatic filariasis(LF)is endemic in Myanmar and targeted for elimination.To highlight the National Programme to Eliminate Lymphatic Filariasis(NPELF)progress between 2000 and 2014,this paper describes the geographical distribution of LF,the scale-up and impact of mass drug administration(MDA)implementation,and the first evidence of the decline in transmission in five districts.Methods:The LF distribution was determined by mapping historical and baseline prevalence data collected by NPELF.Data on the MDA implementation,reported coverage rates and sentinel site surveillance were summarized.A statistical model was developed from the available prevalence data to predict prevalence at township level by year of measurement.Transmission assessment survey(TAS)methods,measuring antigenemia(Ag)prevalence in children,were used to determine whether prevalence was below a level where recrudescence is unlikely to occur.Results:The highest baseline LF prevalence was found in the Central Valley region.The MDA implementation activities scaled up to cover 45 districts,representing the majority of the endemic population,with drug coverage rates ranging from 60.0%to 98.5%.Challenges related to drug supply and local conflict were reported,and interrupted MDA in some districts.Overall,significant reductions in LF prevalence were found,especially after the first 2 to 3 rounds of MDA,which was supported by the corresponding model.The TAS activities in five districts found only two Ag positive children,resulting in all districts passing the critical threshold.Conclusion:Overall,the Myanmar NPELF has made positive steps forward in the elimination of LF despite several challenges,however,it needs to maintain momentum,drawing on international stakeholder support,to aim towards the national and global goals of elimination.