RESUMEN
Lymphatic filariasis (LF) is a crippling and disfiguring parasitic condition. India accounts for 55% of the world's LF burden. The filarial parasite Wuchereria bancrofti is known to cause 99.4% of the cases while, Brugia malayi accounts for 0.6% of the issue occurring mainly in some pockets of Odisha and Kerala states. The Balasore (Baleswar) district of Odisha has been a known focus of B. malayi transmission. We employed molecular xenomonitoring to detect filarial parasite DNA in vectors. In six selected villages, Gravid traps were used to collect Culex mosquitoes and hand catch method using aspirators was followed for collection of mansonioides. A total of 2903 mosquitoes comprising of Cx. quinquefasciatus (n = 2611; 89.94%), Cx. tritaeniorhynchus (n = 100; 3.44%), Mansonia annuliferea (n = 139; 4.78%) and Mansonia uniformis (n = 53; 1.82%) were collected from six endemic villages. The species wise mosquitoes were made into 118 pools, each with a maximum of 25 mosquitoes, dried and transported to the laboratory at VCRC, Puducherry. The mosquito pools were subjected to parasite DNA extraction, followed by Real-time PCR using LDR and HhaI probes to detect W. bancrofti and B. malayi infections, respectively. Seven pools (6.66%) of Cx. quinquefasciatus, showed infection with only W. bancrofti while none of the pools of other mosquito species showed infection with either W. bancrofti or B. malayi. Although the study area is endemic to B. malayi, none of the vectors of B. malayi was found with parasite infection. This study highlights the ongoing transmission of bancroftian filariasis in the study villages of Balasore district of Odisha and its implications for evaluating LF elimination programme.
Asunto(s)
Brugia Malayi , Filariasis Linfática , Wuchereria bancrofti , Animales , Wuchereria bancrofti/aislamiento & purificación , Wuchereria bancrofti/genética , India/epidemiología , Brugia Malayi/genética , Brugia Malayi/aislamiento & purificación , Filariasis Linfática/epidemiología , Filariasis Linfática/parasitología , Filariasis Linfática/transmisión , Humanos , Mosquitos Vectores/parasitología , Culex/parasitología , Enfermedades Endémicas , Femenino , ADN de Helmintos/genética , ADN de Helmintos/análisis , Filariasis/epidemiología , Filariasis/parasitología , Filariasis/transmisiónRESUMEN
BACKGROUND: The Global Program to Eliminate Lymphatic Filariasis (GPELF) is the largest public health program based on mass drug administration (MDA). Despite decades of MDA, ongoing transmission in some countries remains a challenge. To optimise interventions, it is critical to differentiate between recrudescence and new infections. Since adult filariae are inaccessible in humans, deriving a method that relies on the offspring microfilariae (mf) is necessary. METHODS: We developed a genome amplification and kinship analysis-based approach using Brugia malayi samples from gerbils, and applied it to analyse Wuchereria bancrofti mf from humans in Côte d'Ivoire. We examined the pre-treatment genetic diversity in 269 mf collected from 18 participants, and further analysed 1-year post-treatment samples of 74 mf from 4 participants. Hemizygosity of the male X-chromosome allowed for direct inference of haplotypes, facilitating robust maternal parentage inference. To enrich parasite DNA from samples contaminated with host DNA, a whole-exome capture panel was created for W. bancrofti. FINDINGS: By reconstructing and temporally tracking sibling relationships across pre- and post-treatment samples, we differentiated between new and established maternal families, suggesting reinfection in one participant and recrudescence in three participants. The estimated number of reproductively active adult females ranged between 3 and 11 in the studied participants. Population structure analysis revealed genetically distinct parasites in Côte d'Ivoire compared to samples from other countries. Exome capture identified protein-coding variants with â¼95% genotype concordance rate. INTERPRETATION: We have generated resources to facilitate the development of molecular genetic tools that can estimate adult worm burdens and monitor parasite populations, thus providing essential information for the successful implementation of GPELF. FUNDING: This work was financially supported by the Bill and Melinda Gates Foundation (https://www.gatesfoundation.org) under grant OPP1201530 (Co-PIs PUF & Gary J. Weil). B. malayi parasite material was generated with support of the Foundation for Barnes Jewish Hospital (PUF). In addition, the development of computational methods was supported by the National Institutes of Health under grants AI144161 (MM) and AI146353 (MM). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Asunto(s)
Filariasis Linfática , Recurrencia , Reinfección , Wuchereria bancrofti , Filariasis Linfática/parasitología , Filariasis Linfática/epidemiología , Filariasis Linfática/diagnóstico , Filariasis Linfática/genética , Humanos , Animales , Wuchereria bancrofti/genética , Femenino , Masculino , Reinfección/parasitología , Brugia Malayi/genética , Gerbillinae/parasitología , Variación Genética , Microfilarias/genética , Adulto , Haplotipos , Côte d'Ivoire/epidemiologíaRESUMEN
Brugia malayi are thread-like parasitic worms and one of the etiological agents of Lymphatic filariasis (LF). Existing anthelmintic drugs to treat LF are effective in reducing the larval microfilaria (mf) counts in human bloodstream but are less effective on adult parasites. To test potential drug candidates, we report a multi-parameter phenotypic assay based on tracking the motility of adult B. malayi and mf in vitro. For adult B. malayi, motility is characterized by the centroid velocity, path curvature, angular velocity, eccentricity, extent, and Euler Number. These parameters are evaluated in experiments with three anthelmintic drugs. For B. malayi mf, motility is extracted from the evolving body skeleton to yield positional data and bending angles at 74 key point. We achieved high-fidelity tracking of complex worm postures (self-occlusions, omega turns, body bending, and reversals) while providing a visual representation of pose estimates and behavioral attributes in both space and time scales.
Asunto(s)
Brugia Malayi , Microfilarias , Brugia Malayi/fisiología , Animales , Fenotipo , Humanos , Filariasis Linfática/parasitología , Antihelmínticos/farmacologíaRESUMEN
Filariasis, a neglected tropical disease caused by roundworms, is a significant public health concern in many tropical countries. Microscopic examination of blood samples can detect and differentiate parasite species, but it is time consuming and requires expert microscopists, a resource that is not always available. In this context, artificial intelligence (AI) can assist in the diagnosis of this disease by automatically detecting and differentiating microfilariae. In line with the target product profile for lymphatic filariasis as defined by the World Health Organization, we developed an edge AI system running on a smartphone whose camera is aligned with the ocular of an optical microscope that detects and differentiates filarias species in real time without the internet connection. Our object detection algorithm that uses the Single-Shot Detection (SSD) MobileNet V2 detection model was developed with 115 cases, 85 cases with 1903 fields of view and 3342 labels for model training, and 30 cases with 484 fields of view and 873 labels for model validation before clinical validation, is able to detect microfilariae at 10x magnification and distinguishes four species of them at 40x magnification: Loa loa, Mansonella perstans, Wuchereria bancrofti, and Brugia malayi. We validated our augmented microscopy system in the clinical environment by replicating the diagnostic workflow encompassed examinations at 10x and 40x with the assistance of the AI models analyzing 18 samples with the AI running on a middle range smartphone. It achieved an overall precision of 94.14%, recall of 91.90% and F1 score of 93.01% for the screening algorithm and 95.46%, 97.81% and 96.62% for the species differentiation algorithm respectively. This innovative solution has the potential to support filariasis diagnosis and monitoring, particularly in resource-limited settings where access to expert technicians and laboratory equipment is scarce.
Asunto(s)
Inteligencia Artificial , Microscopía , Microscopía/métodos , Humanos , Animales , Filariasis/diagnóstico , Filariasis/parasitología , Microfilarias/aislamiento & purificación , Algoritmos , Teléfono Inteligente , Filariasis Linfática/diagnóstico , Filariasis Linfática/parasitologíaRESUMEN
Nematode infections are common in both humans and livestock, with major adverse planetary health and economic impacts. Wuchereria bancrofti is a parasitic nematode that causes lymphatic filariasis, a neglected tropical disease that can lead to severe disability and deformity worldwide. For the long-term survival of the bancroftian parasites in the host, a complex immune invasion strategy is involved through immunomodulation. Therefore, immunomodulation can serve as a site of research and innovation for molecular targets. Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine crucial to the host antimicrobial alarm system and stress response. Interestingly, the nematode parasite W. bancrofti also produces two homologs of MIF (Wba-MIF1 and 2). Using a mass spectrometry-based phosphoproteomics approach, we report new findings on the immunomodulatory effect and signaling mechanism of Wba-MIF2 in macrophage cells. Accordingly, we observed 1201 phosphorylated sites on 467 proteins. Out of the 1201 phosphorylated sites, 1075, 117, and 9 were found on serine (S), threonine (T), and tyrosine (Y) residues, respectively. Our bioinformatics analysis led to identification of major pathways, including spliceosomes, T cell receptor signaling pathway, Th17 differentiation pathway, interleukin-17 signaling pathway, and insulin signaling pathway upon Wba-MIF2 treatment. Wba-MIF2 treatment also enriched CDK4, CDK1, and DNAPK kinases. The comparison of the signaling pathway of Wba-MIF2 with that of human-MIF suggests both share similar signaling pathways. These findings collectively offer new insights into the role and mechanism of Wba-MIF2 as an immunomodulator and inform future diagnostics and drug discovery research for W. bancrofti.
Asunto(s)
Antiinfecciosos , Filariasis Linfática , Factores Inhibidores de la Migración de Macrófagos , Parásitos , Animales , Humanos , Wuchereria bancrofti/metabolismo , Parásitos/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Filariasis Linfática/parasitologíaRESUMEN
A Organização Mundial de Saúde aponta a Filariose Linfática como endemia potencialmente eliminável. Para isso, foi criado o Programa Global de Eliminação da Filariose Linfática, que possui como uma de suas estratégias o tratamento em massa da população endêmica. A baixa adesão ao tratamento representa um sério obstáculo ao sucesso do programa. Assim, o objetivo deste estudo é descrever o perfil epidemiológico e antigênico e os fatores relacionados a não adesão ao tratamento em massa para filariose linfática no município de Olinda-PE. Trata-se de um estudo de corte transversal, cuja população foi constituída por pessoas que se recusaram a participar do tratamento em massa nos bairros Alto da Bondade e Alto da Conquista, nos anos de 2009 e 2010. Os dados foram coletados através da aplicação de questionários e do teste antigênico (ICT card test). Os indivíduos positivos pelo ICT card test foram avaliados através da filtração (teste parasitológico padrão-ouro). Para o processamento e a análise de dados foi utilizado o programa Epi-Info. Foram pesquisados 102 indivíduos, sendo 51 (50,00 por cento) moradores do Alto da Bondade e 51 (50,00 por cento) do Alto da Conquista. A maioria era do sexo feminino (63,73 por cento) com média de idade de 49,39 anos, e possuía o ensino médio (17,6 por cento). Sobre as características socioambientais, verificou-se que todos os domicílios visitados eram de alvenaria. Cerca de 90por cento possuía abastecimento de água ligado à rede geral e coleta de lixo por serviço de limpeza urbana, porém o esgotamento sanitário era feito através de fossas rudimentares. Do total de pesquisados, quatro (3,92 por cento) apresentaram-se antígeno-positivos para Wuchereria bancrofti através do teste ICT card test), porém não apresentaram positividade na filtração. Os principais motivos encontrados para a não adesão ao tratamento em massa foram o não recebimento da medicação e relacionados às reações adversas, porém tais razões não foram completamente esclarecidas. Novas estratégias são necessárias para o aumento da adesão ao tratamento em massa, dentre as quais ações de educação em saúde e campanhas de sensibilização.
Asunto(s)
Humanos , Niño , Adolescente , Adulto , Filariasis/epidemiología , Negativa del Paciente al Tratamiento , Wuchereria bancrofti , Filariasis Linfática/parasitología , Filariasis Linfática/terapia , Conocimientos, Actitudes y Práctica en Salud , Características de la Población , Condiciones SocialesRESUMEN
Clinical manifestations of extralymphatic disease caused by filariasis are varied and range from symptoms due to tropical pulmonary eosinophilia to hematuria, proteinuria, splenomegaly, and rarely arthritis. Disseminated microfilaremia in association with loculated lung cyst and empyema is of rare occurrence and to the best of our knowledge has not been documented in the literature so far. We report here a case of disseminated microfilaremia due to Wuchereria bancrofti infection accompanied by a lung cyst and empyema in a 21-year-old Indian man.
Asunto(s)
Animales , Humanos , Masculino , Adulto Joven , Quistes/parasitología , Filariasis Linfática/parasitología , Empiema/parasitología , Resultado Fatal , Enfermedades Pulmonares/parasitología , Wuchereria bancrofti/aislamiento & purificaciónRESUMEN
Ao longo do tempo, a maneira como se entende um determinado assunto passa por modificações através da pesquisa científica. Na maioria das vezes, essas mudanças causam pequenas diferenças na estrutura total do tópico em questão. Outras vezes, entretanto, ocorrem mudanças revolucionárias que não só alteram a compreensão do assunto em si, mas promovem a abertura de diferentes perspectivas que podem desencadear o início de novas etapas de interpretações e de novos caminhos de conhecimento. Exemplo disso foram os estudos de Gregor Johann Mendel que levaram à descoberta de leis da hereditariedade que, por sua vez, revolucionaram a biologia e traçaram as bases da genética. Em algumas situações, as mudanças não só modificam a forma de pensar, mas também têm implicações práticas ao melhorar a qualidade de vida de muitos seres humanos. No seu livro A Estrutura de Revoluções Científicas, Thomas Kuhn se refere às ruturas nessa evolução científica como "mudanças de paradigma", um termo que hoje é usado de uma forma genérica para descrever uma modificação profunda em nossos pontos de referência. O paradigma de que o estágio adulto da Wuchereria bancrofti causava a obstrução do vaso linfático e desencadeava uma reação imunológica inevitável em indivíduos predispostos, provocando a elefantíase, foi substituído pela esperança de que ser infectado não mais significa, necessariamente, ser um potencial portador da forma mais deformante da disfunção linfática. A infecção bacteriana secundária de repetição (semelhante clinicamente à erisipela) é hoje reconhecida como o fator mais importante para a instalação e a progressão do linfedema crônico, nos indivíduos que vivem em áreas endêmicas de filariose linfática. Evitar ou minimizar os episódios agudos bacterianos é um processo factível para a maioria dos habitantes das comunidades endêmicas, através do uso regular de água e sabão: a forma mais simples de higiene já conhecida pelo ser humano.
The way a particular subject is understood changes over time as a result of scientific research. In most cases, these changes are minor, with limited effect on the overall knowledge on the subject. Sometimes, however, revolutionary changes occur and not only modify the understanding of the subject but open perspectives that can trigger new interpretations and new ways for expansion of scientific knowledge. The studies of Gregor Johann Mendel were a good example. They led to discovery of the laws of inheritance which, in turn, have revolutionized biology and provided the foundation for genetics. In certain situations, changes not only alter ways of thinking, but have practical implications, also improving the quality of life for many people. In his book The Structure of Scientific Revolutions, Thomas Kuhn refers to discontinuities in scientific development as a "change of paradigm", a term now used in a generic manner to describe a profound changes in our reference points. For lymphatic filariasis the old paradigm stated that Wuchereria bancrofti at the adult stage causes lymphatic vessel obstruction, triggering an inevitable immune response in predisposed individuals and leading to elephantiasis. This has been replaced by a new paradigm, which offers hope that W. bancrofti infection does not necessarily predispose to the disfiguring outward manifestation of lymphatic dysfunction. Repeated secondary bacterial infections (erysipela-like) are now recognized as the most important factor for initiation and progression of chronic lymphedema in individuals living in filariasis-endemic areas. Most inhabitants of endemic communities can prevent and minimize the acute bacterial episodes by regular use of soap and water, the simplest form of hygiene already well known to human beings.
Asunto(s)
Animales , Humanos , Filariasis Linfática/diagnóstico , Diagnóstico Diferencial , Filariasis Linfática/microbiología , Filariasis Linfática/parasitología , Wolbachia/fisiología , Wuchereria bancroftiAsunto(s)
Humanos , Embarazo , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto , Pediatría , Wuchereria bancrofti , Filariasis , Enfermedades Parasitarias , Filariasis Linfática , Filariasis Linfática/diagnóstico , Filariasis Linfática/epidemiología , Filariasis Linfática/etiología , Filariasis Linfática/historia , Filariasis Linfática/parasitología , Filariasis Linfática/terapiaRESUMEN
A microfilaria survey was conducted in Trinidad in 1992, 12 years after mass treatment with spaced doses of diethylcarbamazine citrate (DEC-C) for the control of Bancroftian filariasis; 348 persons were examined using thick blood smears and a membrane filtration technique. They included 104 who had participated in the mass chemotherapy campaign in 1980. No Wuchereria bancrofti microfilariae were detected among 66 percent of the population examined. In 1980, 86 of 592 persons examined were found to be infected with W. bancrofti, 140 with Mansonella ozzardi and 44 with mixed infections, while in 1992, only M. ozzardi infections persisted despite treatment with DEC-C. Of the 104 persons re-examined 12 years later, 46 had M. ozzardi, of which five were new cases, but none had W. bancrofti. During both the 1980 and 1992 surveys, low microfilariae rates for M. ozzardi were observed among those 19 years of age or younger. Of the 302 persons newly examined in 1992, 29 were infected with significantly (P<0.001) more males (79.3 percent) than females (20.9 percent) being microfilaremic. The combined results showed similiar prevalence rates for M. ozzardi from 23.3 percent to 21.6 percent in 1980 and 1992. Nucleopore membrane filtration and thick blood films were very efficient in demonstrating the presence of microfilariae. The usefulness of these methods and spaced treatment using DEC-C are also discussed (AU)
Asunto(s)
Humanos , Antihelmínticos/análisis , Trinidad y Tobago , Filariasis Linfática/parasitología , Trinidad y Tobago , Insectos Vectores , Trinidad y Tobago , Culex , Región del Caribe , Resultado del Tratamiento , Trinidad y Tobago , Wuchereria bancrofti/efectos de los fármacos , Trinidad y TobagoRESUMEN
The fate of 1,092 eggs representing 10 Culex quinquefasciatus was studied to determine life table characteristics under laboratory conditions. Real developmental mortality was high (24.9 percent) with death during the larval instars accounting for 77.4 percent or 10.4 percent of all mortality. The length of the life cycle was 9.5 days, with a larval duration of 7.5 days. The mean observed fecundity of Cx. quinquefasciatus under laboratory conditions was 109.6 +/- 23.29 eggs. The implications for vector control programs are discussed (AU)
Asunto(s)
Culex/metabolismo , Trinidad y Tobago , Insectos Vectores/anatomía & histología , Trinidad y Tobago , Tablas de Vida , Filariasis Linfática/parasitologíaRESUMEN
A random sample bloodsmear survey was conducted during evening hours in Georgetown, Guyana, to determine the prevalence of Wuchereria bancroftilariae. In all, 182 of 2,818 persons tested (6.5 percent) yielded positive results-indicating that the overall prevalence of Bancroftian filariasis has not dimished and may be on the rise. Relatively high prevalences found in children and adolescents point to active transmission. It appears likely that certain socioeconomic and environmental factors have been contributing to such transmission, and that similar factors could encourage increased transmission elsewhere in the Americas as well. (AU)