The Health and Economic Burdens of Lymphatic Filariasis Prior to Mass Drug Administration Programs.

BACKGROUND: The Global Programme to Eliminate Lymphatic Filariasis (GPELF) was launched in 2000 with the goal of eliminating lymphatic filariasis (LF) as a public health problem by 2020. Despite considerable progress, the current prevalence is around 60% of the 2000 figure, with the deadline looming a year away. Consequently, there is a continued need for investment in both the mass drug administration (MDA) and morbidity management programs, and this paper aims to demonstrate that need by estimating the health and economic burdens of LF prior to MDA programs starting in GPELF areas. METHODS: A previously developed model was used to estimate the numbers of individuals infected and individuals with symptomatic disease, along with the attributable number of disability-adjusted life years (DALYs). The economic burden was calculated by quantifying the costs incurred by the health-care system in managing clinical cases, the patients' out-of-pocket costs, and their productivity costs. RESULTS: Prior to the MDA program, approximately 129 million people were infected with LF, of which 43 million had clinical disease, corresponding to a DALY burden of 5.25 million. The average annual economic burden per chronic case was US $115, the majority of which resulted from productivity costs. The total economic burden of LF was estimated at US $5.8 billion annually. CONCLUSIONS: These results demonstrate the magnitude of the LF burden and highlight the continued need to support the GPELF. Patients with clinical disease bore the majority of the economic burden, but will not benefit much from the current MDA program, which is aimed at reducing transmission. This assessment further highlights the need to scale up morbidity management programs.

Disease Burden Estimation of Lymphatic Filariasis in an Endemic Area.

Background: Anecdotal evidence collected by a community organization suggested high prevalence of lymphatic filariasis (LF) in Sitapur district, Uttar Pradesh. Village volunteers subsequently conducted a line listing in 13 villages of Pisawan block and recorded 261 cases of known LF complications, namely hydrocele and lymphedema. This being far higher than official projections, a block-wide cluster survey was conducted to estimate the disease burden more accurately. Methods: Cluster sampling techniques were applied, and 41 clusters selected within Pisawan block. Survey teams comprising one woman and man interviewed member of all households in the cluster, recording details of individuals suffering from hydrocele or lymphedema within them. Age and gender were noted, as well as duration of symptoms and details of any treatment availed. Results: A total of 1851 patients (1256 males and 595 females) were reported to have lymphedema, hydrocele, or both in the 6931 households surveyed. This equates to a prevalence rate of 4.95% (with 9.75% margin of error) in Pisawan block. With these calculations, an estimated 11,049 + 1077 patients with LF complications in Pisawan block, Sitapur, UP in 2016. Conclusions: The high prevalence rate of LF complications in Pisawan block is disconcerting, especially considering India's commitment to eliminate LF by 2020. Compliance with Mass Drug Administration (MDA) must be improved. Furthermore, the Morbidity Management and Disability Prevention (MMDP) component of the National Programme for Elimination of Lymphatic Filariasis (PELF) must be strengthened so that such patients can lead a productive life.

A refined and updated health impact assessment of the Global Programme to Eliminate Lymphatic Filariasis (2000-2020).

BACKGROUND: Lymphatic filariasis (LF) is a neglected tropical disease (NTD). In 2000 the World Health Organization (WHO) established the Global Programme to Eliminate Lymphatic Filariasis (GPELF). A key component of this programme is mass drug administration (MDA). Between 2000 and 2020, the GPELF has delivered over 8.6 billion treatments to at-risk populations. The last impact assessment of the programme evaluated the treatments provided between 2000-2014. The goal of this analysis is to provide an updated health impact assessment of the programme, based on the numbers treated between 2000-2020. METHODS: We updated and refined a previously established model that estimates the number of clinical manifestations and disability-adjusted life years (DALYs) averted by the treatments provided by the GPELF. The model comprises three different population cohorts that can benefit from MDA provided (those protected from acquiring infection, those with subclinical morbidity prevented from progressing and those with clinical disease alleviated). The treatment numbers were updated for all participating countries using data from the WHO. In addition, data relating to the estimated number of individuals initially at risk of LF infection were updated where possible. Finally, the DALY calculations were refined to use updated disability weights. RESULTS: Using the updated model and corresponding treatment data, we projected that the total benefit cohort of the GPELF (2000-2020) would consist of approximately 58.5 million individuals and the programme would avert 44.3 million chronic LF cases. Over the lifetime of the benefit cohorts, this corresponded to 244 million DALYs being averted. CONCLUSION: This study indicates that substantial health benefits have resulted from the first 20 years of the GPELF. It is important to note that the GPELF would have both additional benefits not quantified by the DALY burden metric as well as benefits on other co-endemic diseases (such as soil-transmitted helminths, onchocerciasis and scabies)-making the total health benefit underestimated. As with the past impact assessments, these results further justify the value and importance of continued investment in the GPELF.

Caring for patients in the global programme to eliminate lymphatic filariasis.

Clinical lymphatic filariasis (LF) is a debilitating, disfiguring medical condition with severe psychosocial consequences for patients and their families. Addressing these patients' medical needs is a major component of the global programme to eliminate lymphatic filariasis (GPELF). In the 20 y of providing a minimal package of care many thousands of surgical operations to correct LF hydrocoeles been performed and national programmes in >90% of LF endemic countries have received the training needed to care for their patients. The creation of educational materials detailing appropriate patient care, together with increased funding, have been key catalysts in increasing awareness of clinical LF in recent years. Nevertheless, the implementation of care for these patients has often faced challenges that have led to delays in fully implementing the patient care component of GPELF; these include locating these often stigmatised individuals, maintaining provision of the necessary consumables (e.g. soaps and creams) and maintaining programme support within already overstretched national LF teams. As the LF global programme moves to achieve success by 2030 it will be vital to continue to focus efforts on the care and rehabilitation of those suffering from lymphoedema and hydrocoeles, learning from the experiences of the past 20 y.

Health economic analyses of the Global Programme to Eliminate Lymphatic Filariasis.

The Global Programme to Eliminate Lymphatic Filariasis (GPELF) was established by the WHO in 2000. It aims to eliminate lymphatic filariasis as a public health problem. This paper summarises the key estimates of the cost-effectiveness and economic benefits related to the mass drug administration (MDA) provided by the GPELF. Several studies have investigated the cost-effectiveness of this MDA, estimating the cost per disability-adjusted life year (DALY) averted. These cost-effectiveness estimates have consistently classed the intervention as cost-effective and as favourable compared with other public health interventions conducted in low- and middle-income countries. Studies have also found that the MDA used for lymphatic filariasis control generates significant economic benefits. Although these studies are positive, there are still important gaps that warrant further health economic research (particularly, the evaluation of alternative interventions, further evaluation of morbidity management strategies and evaluation of interventions for settings coendemic with Loa loa). To conclude, health economic studies for a programme as large as the GPELF are subject to uncertainty. That said, the GPELF has consistently been estimated to be cost-effective and to generate notable economic benefits by a number of independent studies.

Economic evaluations of lymphatic filariasis interventions: a systematic review and research needs.

In 2000, the World Health Organization established the Global Programme to Eliminate Lymphatic Filariasis (GPELF), with the goal of eliminating the disease as a public health problem by 2020. Since the start of the programme, a cumulative total of 6.2 billion treatments have been delivered to affected populations - with more than 556 million people treated in 2015 alone. In this paper, we perform a rigorous systematic review of the economic evaluations of lymphatic filariasis interventions have been conducted. We demonstrate that the standard interventions to control lymphatic filariasis are consistently found to be highly cost-effective. This finding has important implications for advocacy groups and potential funders. However, there are several important inconsistencies and research gaps that need to be addressed as we move forward towards the 2020 elimination goals. One of the most important identified research gaps was a lack of evaluation of new interventions specifically targeting areas co-endemic with onchocerciasis and Loa loa - which could become a major barrier to achieving elimination.

The health and economic benefits of the global programme to eliminate lymphatic filariasis (2000-2014).

BACKGROUND: Lymphatic filariasis (LF), also known as elephantiasis, is a neglected tropical disease (NTD) targeted for elimination through a Global Programme to Eliminate LF (GPELF). Between 2000 and 2014, the GPELF has delivered 5.6 billion treatments to over 763 million people. Updating the estimated health and economic benefits of this significant achievement is important in justifying the resources and investment needed for eliminating LF. METHOD: We combined previously established models to estimate the number of clinical manifestations and disability-adjusted life years (DALYs) averted from three benefit cohorts (those protected from acquiring infection, those with subclinical morbidity prevented from progressing and those with clinical disease alleviated). The economic savings associated with this disease prevention was then analysed in the context of prevented medical expenses incurred by LF clinical patients, potential income loss through lost-labour, and prevented costs to the health system to care for affected individuals. The indirect cost estimates were calculated using the human capital approach. A combination of four wage sources was used to estimate the fair market value of time for an agricultural worker with LF infection (to ensure a conservative estimate, the lowest wage value was used). RESULTS: We projected that due to the first 15 years of the GPELF 36 million clinical cases and 175 (116-250) million DALYs will potentially be averted. It was estimated that due to this notable health impact, US$100.5 billion will potentially be saved over the lifetimes of the benefit cohorts. This total amount results from summing the medical expenses incurred by LF patients (US$3 billion), potential income loss (US$94 billion), and costs to the health system (US$3.5 billion) that were projected to be prevented. The results were subjected to sensitivity analysis and were most sensitive to the assumed percentage of work hours lost for those suffering from chronic disease (changing the total economic benefit between US$69.30-150.7 billion). CONCLUSIONS: Despite the limitations of any such analysis, this study identifies substantial health and economic benefits that have resulted from the first 15 years of the GPELF, and it highlights the value and importance of continued investment in the GPELF.