Lymphatic Filariasis Programme Research Articles

Predictors of Compliance in Mass Drug Administration for the Treatment and Prevention of Lymphatic Filariasis in Leogane, Haiti

The global strategy for the elimination of lymphatic filariasis (LF) is based on annual mass drug administration (MDA) to interrupt transmission. Noncompliance with MDA represents a serious programmatic obstacle for the LF program because systematically noncompliant individuals may serve as a reservoir for the parasite and permit recrudescence of infection. Using a survey questionnaire concerning practices, beliefs, and attitudes towards MDA, we assessed differences between noncompliant individuals and compliant individuals in Leogane, Haiti (n = 367) after four years of treatment. A logistic regression model showed the odds of being noncompliant were significantly increased for women (odds ratio = 2.74, 95% confidence interval = 1.12-6.70), as well as for people who lacked knowledge about both LF and programs to eliminate infection. Public health programs should be designed to target people who are at risk for systematic noncompliance.

National Mass Drug Administration Costs for Lymphatic Filariasis Elimination

BackgroundBecause lymphatic filariasis (LF) elimination efforts are hampered by a dearth of economic information about the cost of mass drug administration (MDA) programs (using either albendazole with diethylcarbamazine [DEC] or albendazole with ivermectin), a multicenter study was undertaken to determine the costs of MDA programs to interrupt transmission of infection with LF. Such results are particularly important because LF programs have the necessary diagnostic and treatment tools to eliminate the disease as a public health problem globally, and already by 2006, the Global Programme to Eliminate LF had initiated treatment programs covering over 400 million of the 1.3 billion people at risk.Methodology/Principal FindingsTo obtain annual costs to carry out the MDA strategy, researchers from seven countries developed and followed a common cost analysis protocol designed to estimate 1) the total annual cost of the LF program, 2) the average cost per person treated, and 3) the relative contributions of the endemic countries and the external partners. Costs per person treated ranged from $0.06 to $2.23. Principal reasons for the variation were 1) the age (newness) of the MDA program, 2) the use of volunteers, and 3) the size of the population treated. Substantial contributions by governments were documented – generally 60%–90% of program operation costs, excluding costs of donated medications.Conclusions/SignificanceMDA for LF elimination is comparatively inexpensive in relation to most other public health programs. Governments and communities make the predominant financial contributions to actual MDA implementation, not counting the cost of the drugs themselves. The results highlight the impact of the use of volunteers on program costs and provide specific cost data for 7 different countries that can be used as a basis both for modifying current programs and for developing new ones.

The impact of integrating the elimination programme for lymphatic filariasis into primary health care in the Dominican Republic

Integration of disease-specific programmes into existing health care delivery systems is a challenge for many countries, made more salient as the scope and scale of disease-specific programmes increases. This paper reports on the programmatic outcomes of 2 years of integrating the lymphatic filariasis (LF) elimination programme into primary health care (PHC) in the Dominican Republic during a period of national health care reform and decentralization. Data were collected retrospectively from community volunteers, PHC staff and LF programme staff using a mix of quantitative and qualitative methods. Benefits of integration for LF elimination included increasing the extent of the geographic coverage of mass drug administration (MDA) and a 21% increase in municipalities achieving the MDA target coverage rate of 80%. Benefits which accrued to PHC included improved information systems and strengthened relationships between the health services and the community. This study also identified challenges to implementing integration and the solutions found. These include the importance of focusing on the professional development of disease-specific program staff as their roles change, strengthening specific weakness in the general health system and finding alternative solutions where these are not easily solved, actively engaging senior management at an early stage, continually evaluating the impact of integration and not pushing integration for the sake of integration.

Prevalence of soil transmitted nematodes on Nukufetau, a remote Pacific island in Tuvalu

BackgroundThe population of Nukufetau, a remote coral atoll island in Tuvalu in the Western Pacific, received annual mass drug administration (MDA) of diethylcarbamazine and albendazole under the Pacific Elimination of Lymphatic Filariasis program in 2001, 2002 and 2003, with the last MDA occurring six months before a cross-sectional survey of the whole population for soil transmitted helminths (STH).MethodsA cross-sectional survey in May 2004 recruited 206 residents (35.2% of the population) who provided a single faecal sample that was preserved, concentrated and examined microscopically.ResultsOverall prevalence of STH was 69.9%; only hookworm and Trichuris trichiura were diagnosed. Trichuris was present in 68.4% with intensity of infection being light in 56.3%, medium in 11.7% and heavy in 0.5%. Hookworm occurred in 11.7% with intensity of infection 11.2% being light and medium in 0.5%. Twenty individuals (9.7%) had dual infections. The prevalence of Trichuris was constant across all ages while the prevalence of hookworm was significantly lower in residents below 30 years of age. In the age group 5–12 years comparison of results with a 2001 survey [1] suggested that the prevalence of STH has declined minimally, due to sustained high prevalence of Trichuris, while hookworm has declined dramatically from 34.4% to 1.6%.ConclusionThe results of this survey suggest that although the MDA appears to have reduced hookworm prevalence in residents below 30 years of age, there has been minimal effect on Trichuris prevalence. An integrated program to control STH is required.

Short communication: Impact of long‐term (14 years) bi‐annual ivermectin treatment on Wuchereria bancrofti microfilaraemia

Ivermectin has been and continues to be extensively used to control onchocerciasis in areas of hyper and mesoendemicity within the African Programme of Onchocerciasis Control. As programmes to eliminate lymphatic filariasis (LF) caused by Wuchereria bancrofti expand, areas of coendemicity with onchocerciasis will be incorporated into LF programmes. This study reports that in villages which were hyperendemic for onchocerciasis after some 14 years of treatment with ivermectin, no W. bancrofti could be detected in a population of 1210 individuals whilst in adjacent villages a prevalence of around 3% was found. Despite the long period of ivermectin treatment Mansonella perstans did not appear to respond to ivermectin in this setting.

COMMUNITY-WIDE REDUCTION IN PREVALENCE AND INTENSITY OF INTESTINAL HELMINTHS AS A COLLATERAL BENEFIT OF LYMPHATIC FILARIASIS ELIMINATION PROGRAMS

Annual mass treatment with antifilarial drugs is the cornerstone of the global program to eliminate lymphatic filariasis (LF). Although the primary goal of the program is to interrupt transmission of LF, additional public health benefits also are expected because of the known anthelminthic properties of these drugs. Since rapid re-infection with intestinal helminths occurs following treatment, annual de-worming may not be sufficient to produce a lasting reduction in the prevalence and intensity of these infections. We conducted stool examinations in four sentinel communities before and approximately nine months after each of two rounds of mass drug administration (MDA) with diethylcarbamazine and albendazole in the context of an LF elimination program in Leogane, Haiti. At baseline, overall Ascaris, Trichuris, and hookworm infection prevalences were 20.9%, 34.0%, and 11.2%, respectively (n = 2,716 stools). Nine months after the second MDA, Ascaris, Trichuris and hookworm prevalences had decreased significantly, to 14.1%, 14.6%, and 2.0%, respectively (n = 814 stools). Infection intensity decreased significantly for all three parasites as well. These results demonstrate that substantial reductions in intestinal helminth infections are associated with mass treatment of filariasis in Haiti and are consistent with the conclusion that high levels of coverage for the LF program can decrease transmission of geohelminths.

Mass drug treatment for lymphatic filariasis and onchocerciasis.

This review summarizes the progress towards control of lymphatic filariasis (LF) and onchocerciasis, focussing on the impact of mass drug administration (MDA) programmes, in particular those that have developed following the donation of ivermectin and albendazole. The contrasting strategies and objectives of the different programmes are compared, and the impact on transmission, clinical disease and public health assessed. The constraints on programme success are: (i) the absence of a macrofilaricide, which can be used in a public health context; (ii) the sustainability of high coverage of ivermectin over many years in onchocerciasis control; and (iii) the problem of treatment in areas where Loa loa (tropical eye worm) is co-endemic with onchocerciasis because of the rare severe adverse events. LF programmes are expanding rapidly in over 30 countries, where circa 60 million people received treatments in 2002. No serious adverse events have been associated with MDAs for LF elimination. Research on new approaches to treatment using antibiotics are showing promising results in pilot settings because doxycyline has been shown to have long-term embryostatic effects and sustained reductions of microfilaria loads in onchocerciasis and bancroftian filariasis.

Lymphatic Filariasis (Elephantiasis) Elimination: A public health success and development opportunity

BackgroundThe Global Programme to Eliminate Lymphatic Filariasis, launched following World Health Assembly Resolution 50.29 (WHA 50.29), has been facilitated in its progress by new research findings, drug donations, the availability of diagnostic tools, disability management strategies to help those already suffering and the development of partnerships. The strategy recommended by the World Health Organization of annual treatment with a two-drug combination has proved safe.DiscussionUsing different approaches in several countries the elimination of lymphatic filariasis (LF) has been demonstrated to be feasible during earlier decades. These successes have been largely overlooked. However, the programme progress since 2000 has been remarkable – upscaling rapidly from 2 million treatments in 2000 to approximately 60 million in 2002. Around 34 countries had active programmes at the end of 2002. It is anticipated that there will be further expansion – but this will be dependent on additional resources becoming available. The programme also provides significant opportunities for other disease control programmes to deliver public health benefits on a large scale. Few public health programmes have upscaled so rapidly and so cost-effectively (<$0.03/treatment in some Asian settings) – one country treating 9–10 million people in a day (Sri Lanka). The LF programme is arguably the most effective pro-poor public health programme currently operating which is based on country commitment and partnerships supported by a global programme and alliance. Tables are provided to summarize programme characteristics, the benefits of LF elimination, opportunities for integration with other programmes and relevance to the Millennium Development Goals.SummaryLymphatic filariasis elimination is an "easy-to-do" inexpensive health intervention that provides considerable "beyond filariasis" benefits, exemplifies partnership and is easily evaluated. The success in global health action documented in this paper requires and deserves further support to bring to fruition elimination of lymphatic filariasis as a public health problem and health benefits to poor people. A future free of lymphatic filariasis will reduce poverty and bring better health to poor people, prevent disability, strengthen health systems and build partnerships.

Current status and future prospects of the Global Lymphatic Filariasis Programme.

Lymphatic filariasis is recognized as one of the world's most disabling diseases. Adult lymphatic filarial nematodes live for several years; they infest the lymphatic and blood systems, and are transmitted via mosquito vectors. Acute and chronic disease can develop, manifesting as acute inflammation, hydrocoele, lymphoedema and elephantiasis. The development of a global programme for the elimination of lymphatic filariasis (focusing on disease caused by Wuchereria bancrofti) followed a resolution by the World Health Assembly in 1997 that endemic countries should develop programmes to eliminate lymphatic filariasis as a public health problem. This developed from an earlier recommendation by the International Task Force for Disease Eradication in 1993 that lymphatic filariasis was one of six diseases that could, in theory, be eradicated. Herein we review the current status and future prospects of the Global Lymphatic Filariasis Programme, which was launched in 2000.