Introduction. Accurate detection of filarial parasites in humans and vectors is essential for the implementation and evaluation of Global and National Programs to eliminate lymphatic filariasis. Immunological methods to detect infection are available; however, cross-reactivity issues have been reported in most of them. Nucleic acid-based molecular assays offer high levels of specificity and sensitivity and can be used to detect the infections. Methods. In this study, we evaluated loop-mediated isothermal amplification (LAMP) tests to amplify Wuchereria bancrofti DNA in patients’ blood. The amplicons were tested by both pH-sensitive dyes for enhanced visual detection and agarose gel electrophoresis. A closed-tube LAMP assay was also evaluated. Cohen’s Kappa statistics was used for statistical analysis of the assays. 125 patients consented for blood sampling which were used for clinical analysis of LAMP assays with the PCR method used as the “gold standard.” Results. The sensitivity of the evaluated Wuchereria bancrofti LAMP was 92.3%, with a specificity of 97.3% and kappa statistics value of 0.84, which is in a strong agreement. Conclusion. In this study, LAMP assays coupled with fluorescence dye detection have been found to be suitable for diagnosis and monitoring of Wuchereria bancrofti infections in the Kenyan population.
IntroductionLymphatic filariasis is a debilitating disease caused by filarial worms; Wuchereria bancrofti, Brugia Malayi and B. Timori. It is earmarked for elimination by the year 2020 through the Global Program for the Elimination of Lymphatic Filariasis (GPELF). In Kenya, mass treatment has been ongoing since the year 2002 though it has not been consistent as recommended by World health organization (WHO). Taking this into account, the emergence of W. bancrofti resistance strains against the current choice of drugs cannot be ruled out. Information on genetic structure and variations is important in assessment of Program's success. Data on genetic characterization of W. bancrofti in Kenya is lacking. This study, therefore reports the first genetic diversity of W. bancrofti in two Kenyan endemic regions. Methodology Genomic DNA was extracted from 100 human blood samples obtained from Mpirani district in Malindi and Kipini district in Tana River Delta. They were then amplified by PCR and detected through gel electrophoresis. Seventeen PCR products positive for Wuchereria PCR bancrofti were purified and then DNA quantified for Sanger sequencing. Chromas version 2.6.5 and BioEdit softwares were used for sequence alignment and editing. Fourteen sequences were selected for analysis by MEGA7 and six more related sequences retrieved from the Gene Bank for further analysis with the study sequences. Intrapopulation, interpopulation diversity and pair wise distance were determined and the phylogenetic trees constructed. Tajima's D-test of neutrality was also determined and Statistical evolutionary rate was done using Chi-square (X 2 ) test. Results and DiscussionThe mean diversity of Malindi and Tana River Delta isolates was 1.42 and the overall mean distance was 0.99. Tajima's (D) test for test of Neutrality was 4.149 and nucleotide diversity ) ( was 0.603. These results revealed high genetic variations of W. bancrofti in Kenyan endemic regions. This variation could be attributed to prolonged use of the mass drug administration (MDA) and the long period of parasite circulation in these populations.
Lymphatic filariasis is a mosquito borne disease which leads to abnormal painful enlarged body parts, severe disability and social stigma. Early diagnosis and interventions are paramount towards achieving the elimination goal. We screened Wuchereria bancrofti in Matayos constituency in Busia County. Blood samples were collected from 23 clinical units selected purposively based on clinical case reports. Finger prick and/or venous blood sampling and mosquito collections was carried out. Antigenaemia and filarial DNA prevalence were determined. infection rates on mosquito pools were estimated. SPSS version 27 was used for descriptive statistics analysis. A total of 262 participants were recruited, 73.3% of the participants were asymptomatic, 14.1% had swollen legs, 5.3% had painful legs and 3.8% with scrotal swellings. Antigenemia prevalence was 35.9% and DNA prevalence was at 8.0%. A total of 1305 mosquitoes were collected belonging to different species. Two pools out of 78 were positive for filarial DNA with a minimum infection rate of 0.15%. Antigenaemia and infected mosquitoes indicate active transmission. The clinical signs are evidence that filarial infections have been in circulation for over 10 years. Further screening, Mass Drug Administration (MDA), Morbidity management and enhanced mosquito controls are highly recommended.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.