Filaria journal最新文献

BACKGROUND: Ov-CHI-1 is a chitinase specifically expressed in the infective stage larvae of the human filarial parasite Onchocerca volvulus. Evidence has show that it could be a vaccine candidate, however, there is no data available regarding the immunological status of people naturally exposed to infective stage larvae and thus provoked by this antigen. METHOD: We analysed the Ov-CHI-1-specific immune response present in four endemic foci of human onchocerciasis (Ecuador, Nigeria, Togo and Cameroon) by enzyme-linked immunosorbent assays and T-cell proliferation assays. RESULTS: In these foci of infection, antibodies to Ov-CHI-1 were found to be present in only 22% of individuals from Ecuador, but were detected in 42-62% of infected individuals in the three foci from West Africa (Nigeria, Togo and Cameroon). There was found to be no relationship between antibody level and age, gender, or infection intensity as indicated by microfilarial density and numbers of skin nodules. The isotype response to Ov-CHI-1 was dominated by the presence of IgG3, IgG1 was present to a lesser extent. Our results show a positive correlation between N- and C-termini of Ov-CHI-1 in their ability to provoke humoral and cellular immune responses in the human. Peripheral blood mononuclear cell (PBMC) proliferative responses to Ov-CHI-1 when assayed, were found to be significantly higher in the individuals from endemic areas and there was a statistically elevated response to Ov-CHI-1 in the infected individuals when compared to putative immune individuals. CONCLUSION: Ov-CHI-1 is an antigen that we have found strongly induces both humoral and cellular immune responses in humans.

BACKGROUND: Morbidity management is a core component of the global programme for the elimination of lymphatic filariasis. In a double-blind clinical trial, the tolerability and efficacy of Daflon (500 mg) + DEC (25 mg) or DEC (25 mg) alone, twice daily for 90 days, was studied in 26 patients with bancroftian filarial lymphoedema. RESULTS: None of the patients in either drug group reported any adverse reaction throughout the treatment period (90 days). Haematological and biochemical parameters were within normal limits and there was no significant difference between the pre-treatment (day 0) and post-treatment (day 90) values. The group receiving Daflon showed significant reduction in oedema volume from day 90 (140.6 PlusMinus; 18.8 ml) to day 360 (71.8 PlusMinus; 20.7 ml) compared to the pre-treatment (day 0, 198.4 PlusMinus; 16.5 ml) value. This accounted for a 63.8% reduction in oedema volume by day 360 (considering the pre-treatment (day 0) as 100%). In the DEC group, the changes in oedema volume (between day 1 and day 360) were not significant when compared to the pre-treatment (day 0) value. The percentage reduction at day 360 was only 9%, which was not significant (P > 0.05). CONCLUSION: This study has shown that Daflon (500 mg, twice a day for 90 days) is both safe and efficacious in reducing oedema volume in bancroftian filarial lymphoedema. Further clinical trials are essential for strengthening the evidence base on the role of this drug in the morbidity management of lymphatic filariasis.

Low cost reduction of morbidity in lymphoedema is an essential goal in the management of lymphatic filariasis. This review emphasises the role of movement and elevation, and refers to the literature on the effects of these on the venous and lymphatic system. The patient with lymphoedema becomes increasingly immobile and the affected limb is often in a permanently dependent position causing venous hypertension and resultant overloading of the failing lymphatics. The evidence that breathing exercises are important for reducing venous hypertension and inducing lymphatic flow is discussed.The contribution of a damaged epidermis to lymphatic failure is emphasised. Loss of barrier function encourages penetration of bacteria and stimulates repair mechanisms that generate cytokines, which, in turn lead to inflammation. Management programmes that improve the health of the epidermis play a part in reducing lymphatic load.In taking morbidity management of lymphoedema into the general health services there are benefits in promoting skin hygiene and self-help regimes that can ameliorate many diseases along with lymphoedema.

BACKGROUND: Ultrasonography is able to detect adult Wuchereria bancrofti worms in scrotal lymphatic vessels of infected men on account of the characteristic pattern of adult worm movements, known as the filarial dance sign. Furthermore, the technique is able to delineate associated pathology, such as hydrocoele and lymphoedema, which can be diagnosed in early stages. Ultrasonography is also useful in the assessment of macrofilaricidal effects of antifilarial medication.The purpose of this study was to evaluate the usefulness of scrotal ultrasonography, in combination with a new method of digital documentation, in men infected with Wuchereria bancrofti. METHODS: Ultrasonography of the scrotal areas was carried out in 33 male patients from an endemic area in Ghana using a hand-carried ultrasound system and a linear array transducer at 7.5 MHz. Wuchereria bancrofti infection was also assessed by quantification of night blood microfilaraemia and semi-quantitative detection of circulating filarial antigen. Ultrasound findings were documented by print outs and by Digital Video sequences directly exported from the ultrasound machine which were edited in Final Cut Pro 3ledR; and exported, using QuickTimecircledR; Pro, as MPEG-1 video. RESULTS: Worm nests, i.e. dilated lymphatic vessels with the characteristic movement patterns of worms, were found in all patients, and typical examples of larger as well as smaller nests are presented through MPEG-1 video in b- and m-modes as well as Colour Doppler and Pulse Wave Doppler images. CONCLUSION: In this study, the filarial dance sign is being made available on the Internet to readers through MPEG-1 video. This method allows for demonstration of movement patterns rather than static images. In addition, the pathologic ultrasonographic signs of filariasis can be rapidly relayed over great distances and may be helpful to other investigators or clinicians in the diagnosis of patients infected with Wuchereria bancrofti.

Sixty-four experts from a variety of disciplines attended a Conference on the Eradicability of Onchocerciasis at The Carter Center, in Atlanta GA, held January 22-24, 2002. The Conference, which was organized by The Carter Center and the World Health Organization, with funding from the Bill & Melinda Gates Foundation, addressed the question: "Is onchocerciasis (River Blindness) eradicable with current knowledge and tools?" Former US President Jimmy Carter attended part of the final plenary proceedings on January 24.The Conference consisted of a series of presentations by invited expert speakers (Appendix C) and further deliberations in four workgroups (Appendix D) followed by plenary discussion of major conclusions. The presentations underlined epidemiological and entomological differences between onchocerciasis in Africa and the Americas. Whilst onchocerciasis in Africa covers extensive areas and is associated with striking human and fly population migrations and remarkably efficient black fly vectors, in the Americas onchocerciasis is found in limited foci. Human and fly population migration are not major problems in the Americas, where most black fly species are inefficient, though some efficient black flies are also found there. Vector control has been effectively applied in the Onchocerciasis Control Program in West Africa (OCP) with remarkable results, interrupting transmission in most parts of the original Program area. The use of ivermectin has given variable results: while ivermectin treatment has been effective in all endemic areas in controlling onchocerciasis as a public health problem, its potential for interrupting transmission is more promising in hypo- and mesoendemic areas. The African Program for Onchocerciasis Control (APOC), which supports onchocerciasis control in endemic African countries outside the OCP, applies ivermectin, its principal control tool, to communities in high-risk areas as determined by rapid epidemiological mapping of onchocerciasis (REMO) and Geographic Information Systems (GIS). In the Americas, through support of the Onchocerciasis Elimination Program in the Americas (OEPA), a strategy of bi-annual ivermectin treatment of at least 85% of the eligible populations in all endemic communities is showing very good results and promises to be effective in eliminating onchocerciasis in the region.The Conference concluded that onchocerciasis is not eradicable using current tools due to the major barriers to eradication in Africa. However, the Conference also concluded that in most if not all the Americas, and possibly Yemen and some sites in Africa, transmission of onchocerciasis can be eliminated using current tools. The Conference recommended that where interruption of transmission is feasible and cost effective, programs should aim for that goal using all appropriate and available interventions so that the Onchocerca volvulus can eventually be eliminated and interventions halted. Although interruption of

BACKGROUND: Hygiene and skin care are effective and important interventions in the management of lymphoedema secondary to lymphatic filariasis. We analyzed the impact on the quality of life that education and introduction of a designated nurse had on lymphoedema patients in a community that was endemic for lymphatic filariasis. METHODS: Patients' life quality was assessed using a Dermatology Life Quality Index (DLQI) questionnaire. At the same time they received education on appropriate hygiene, skin care techniques and simple exercises that encourage lymph drainage. A designated nurse was provided with educational materials and treatments. The DLQI life quality measure was repeated one year later. RESULTS: The DLQI improved for all patients and reported acute attacks were reduced. A paired t-test showed the improvement in DLQI to be highly significant (P = < 0.0001). CONCLUSIONS: A nurse-led service combined with patient education in communities endemic for lymphatic filariasis is an effective intervention in improving the quality of life of patients with lymphoedema.

BACKGROUND: The tolerability and efficacy of single dose albendazole (400 mg), diethylcarbamazine citrate (DEC) (6 mg/kg bodyweight) or co-administration of albendazole (400 mg) + DEC (6 mg/kg bodyweight) was studied in 54 asymptomatic Wuchereria bancrofti microfilaraemic volunteers in a double blind hospital-based clinical study. RESULTS: There was no significant difference in the overall incidence of adverse reactions between the three drug groups [42.1% (albendazole), 52.9% (DEC) and 61.1% (albendazole + DEC); P > 0.05]. The mean score of adverse reaction intensity did not differ significantly between the DEC and albendazole + DEC groups. However, the values in these two groups were significantly higher compared to that of albendazole alone [1.8 +/- 3.0 (albendazole) vs. 5.6 +/- 7.1 (DEC), 6.7 +/- 6.6 (albendazole + DEC); P < 0.05]. By day 360 post-therapy there was no significant difference between the three drug groups in relation to the clearance of microfilaria [26.3% (albendazole), 17.6% (DEC), 27.8% (albendazole + DEC)], reduction in geometric mean parasite density [94.7% (albendazole), 89.5% (DEC), 95.4% (albendazole + DEC)] or reduction in filarial antigenaemia [83% (albendazole), 87% (DEC), 75% (albendazole + DEC)]. Furthermore, there was a significant decrease in mean geometric parasite density (P < 0.05) as well as antigenaemia optical density values (P < 0.01) between pre-therapy levels and day 360 post-therapy in all three groups. CONCLUSIONS: This study has shown that single dose albendazole (400 mg) has similar efficacy in the clearance of microfilaria as that of DEC or the co-administration of the two drugs. The results strengthen the rationale of using albendazole for mass annual single dose administration for the control of transmission of lymphatic filariasis.