The Mectizan Donation Program (MDP).

The launch of the Mectizan Donation Program (MDP) in 1987, by Merck & Co., Inc., created a number of new opportunities for onchocerciasis control. The microfilaricide Mectizan was rapidly put to ?use by the Onchocerciasis Control Programme in West Africa (OCP), for mass treatment by field teams in selected areas. Other milestones in Mectizan treatment included the establishment, in 1992, of the Onchocerciasis Elimination Program for the Americas, and the creation of the African Programme for Onchocerciasis Control (APOC) in 1995, the latter programme covering all African countries in need outside of the OCP area. In 1998, the donation of Mectizan was expanded to include the treatment of lymphatic filariasis in those African countries where that disease is co-endemic with onchocerciasis. In the past, the development of a broad partnership around the MDP played a very important role, including non-governmental development organizations collaborating with the ministries of health in endemic countries. A new community-directed treatment strategy, which made it easier to reach out to all those in need, including those in remote areas, was developed by the APOC in collaboration with the World Health Organization's Special Programme for Research and Training in Tropical Diseases (TDR). Several drug-management issues, including dosing, shelf-life, safety, and the reporting of severe adverse experiences, were addressed by the MDP, through its Mectizan Expert Committee, and by Merck & Co., Inc. A major research effort for the safe treatment of onchocerciasis in loiasis-endemic areas has also been supported by the MDP. Presently there are national programmes for Mectizan mass treatment in all 33 endemic countries in need of such treatment; >69 million Mectizan treatments for onchocerciasis were provided during 2006, and this number is expected to grow to at least 100 million treatments/year by 2010. This achievement has resulted in great public-health and socio-economic benefits for the populations concerned. Future challenges will include additional support to 'fragile states' resulting from conflicts or natural disasters, and the need for a strengthened primary healthcare (PHC) infrastructure. The community-directed-treatment approach has been a great success but there is still a need to link the treatments to PHC, for the long-term sustainability of the treatments. The presence of loiasis in vast areas of Central Africa imposes a need for the mapping of that disease, and the application of safety precautions when distributing Mectizan in those areas. The recent decision to extend the APOC up to 2015 should facilitate the building of sustainable Mectizan treatment programmes that are integrated with the control of other neglected tropical diseases, such as lymphatic filariasis, intestinal helminths and trachoma. It will be important to define the safe end-point for Mectizan treatment in various settings, and an ongoing study by TDR will address this issue. There is also a need to consider the application of more frequent Mectizan treatments, possibly with adjunct measures, such as ground-based vector control in selected areas, or new chemotherapeutic approaches (as and when they become available).

Operational lessons from 20 years of the Mectizan Donation Program for the control of onchocerciasis.

The donation of ivermectin (Mectizan, Merck & Co., Inc.) to control onchocerciasis (river blindness) was established in 1987 and has since gradually expanded to provide for >570 million treatments cumulatively over the past 20 years. The Mectizan Donation Program (MDP) operates within a broad partnership in 33 endemic countries in need of mass treatment. Particular operational methods and tools are applied to facilitate ivermectin mass treatment. Drug management has been streamlined, including dosing, tablet size and packaging, and monitoring for adverse events. Much of the experience gained in the development of ivermectin mass treatment can be usefully applied in the recent broader perspective of control of neglected tropical diseases. The most important operational lessons of the MDP include: (i) the need to easily define the target population for treatment using rapid, non-invasive techniques; (ii) the value of a broad partnership; (iii) the great potential of working through community-directed treatment; (iv) the need to streamline all drug management aspects and (v) the importance of operations research to tackle new challenges.

Health care at the end of the road: opportunities from 20 years of partnership in onchocerciasis control.

The unprecedented decision of Merck & Co., Inc., to donate ivermectin through the Mectizan(R) Donation Program, has catalysed an exemplary partnership, to distribute the drug to the communities at risk of onchocerciasis, and empower them to take charge of the drug distribution themselves. Integration with other activities has always been part of the plan, but has been accelerated in recent years because of the need to strengthen primary health care, and to meet the challenges of integrating the rapid impact of Neglected Tropical Disease programmes. Activities that have been integrated include provision of vitamin A capsules, elimination of lymphatic filariasis, the distribution of insecticide-treated nets, and comprehensive eye health. Although these integrated activities show promising results for all programmes involved, challenges still remain. The risk of overburdening communities with multiple activities, and the problem of remuneration at the community level, are the major concerns, as is the need for effective coordination. The expanded onchocerciasis control partnership is a model of translating the eighth Millennium Development Goal (MDG), namely 'develop a global partnership for development', into action and also addresses other key MDGs. In 2006, the partnership provided more than 62 million treatments for onchocerciasis control, and offers a firm foundation from which to deliver other needed health interventions while safeguarding the achievements of onchocerciasis control thus far.

Towards the elimination of onchocerciasis.

Human onchocerciasis is a severely disabling filarial disease that is endemic in 28 African countries, six Latin American countries and Yemen. The disease causes a high burden of blindness and visual loss, along with itching and other severe dermal manifestations. It constitutes a significant obstacle to socio-economic development in highly endemic riverine areas, where the Simulium blackflies that act as vectors breed. Onchocerciasis has been subject to control efforts for more than 50 years, initially mainly through vector control but since 1988, with free access to ivermectin (Mectizan), also through large-scale chemotherapy. The Onchocerciasis Control Programme in West Africa operated successfully from 1974 to 2002 in 11 countries, covering the worst savannah foci of the disease through vector control and, in its later stages, also through ivermectin distribution. The African Programme for Onchocerciasis Control was established in 1995, to cover the remaining endemic areas in Africa, with the sustainable annual distribution of ivermectin by 2010 its main goal. Meanwhile, the Onchocerciasis Elimination Program for the Americas is making rapid progress in the virtual regional elimination of the disease through ivermectin distribution, which is achievable primarily because the vectors in the western hemisphere are less efficient than those elsewhere. The global elimination of onchocerciasis as a public-health problem is now within reach but this will require long-term strategies to secure the great gains made so far, through ivermectin treatment and local vector control. Research is needed to define the optimal approaches with the existing tools and to intensify the development of alternative strategies, such as macrofilaricidal drugs for wide-scale use.

A simplified cataract grading system.

A simplified method for grading the presence and severity of different cataract types is needed for field use in assessment of the magnitude of the cataract problem. A cataract grading system was developed by a panel of experts with the objective of making available a simple system for use with a slit lamp to allow for the reliable grading of the most common forms of cataract by relatively inexperienced observers. Three levels, reflecting progressive severity, for grading of nuclear, cortical and posterior subcapsular (PSC) cataract were included in the classification; three standard photos were used for grading nuclear cataract. Field evaluation from four different sites indicated very good to fair interobserver agreement with the use of this system following minimal training of residents in ophthalmology at each site. Further testing of this system is warranted. The WHO simplified cataract grading system should allow for the obtaining of comparable data across countries based on field assessment of the most common forms of cataract.

The global impact of eye injuries.

Using data compiled from the ophthalmic literature and WHO's Blindness Data Bank, the available information on eye injuries from an epidemiological and public health perspective has been extensively reviewed. This collection of data has allowed an analysis of risk factors, incidence, prevalence, and impact of eye injuries in terms of visual outcome. However, most of the estimates are based on information from More Developed Countries (MDCs). The severity of eye injuries can be assessed through proxy indicators such as: (i) potentially blinding bilateral injuries; (ii) open-globe injuries; (iii) endophthalmitis; (iv) enucleation or (v) defined visual impairment. Major risk factors for ocular injuries include age, gender, socioeconomic status and lifestyle. The site where the injury occurs is also related to a risk situation. Available information indicates a very significant impact of eye injuries in terms of medical care, needs for vocational rehabilitation and great socioeconomic costs. The global pattern of eye injuries and their consequences emerging from the present review, undertaken for planning purposes in the WHO Programme for the Prevention of Blindness, suggests that: some 55 million eye injuries restricting activities more than one day occur each year; 750,000 cases will require hospitalization each year, including some 200,000 open-globe injuries; there are approximately 1.6 million blind from injuries, an additional 2.3 million people with bilateral low vision from this cause, and almost 19 million with unilateral blindness or low vision. Further epidemiological studies are needed to permit more accurate planning of prevention and management measures; a standardized international template for reporting on eye injuries might be useful to this effect, along the lines of the reporting occurring through the US Eye Injury Registry.

Prevention of blindness--WHO's mission for vision.

Changes in the world order and in technology during the last half-century have revolutionized approaches to blindness prevention and sight restoration. Although the possibilities have improved and increased immeasurably, unnecessary blindness will remain common, especially among the poor, unless a concerted international effort is made to prevent it.

[Progress in the control of world blindness and future perspectives]. / Progrès réalisés dans la lutte contre la cécité dans le monde et perspectives d'avenir.

Worldwide, there are approximately 180 million severely visually impaired people, of whom some 45 million are blind. Cataract remains the major cause of blindness, especially in the less developed countries. Substantial improvements have been achieved in the control of blinding diseases, mainly in respect of onchocerciasis and xerophthalmia. More recently, a WHO alliance for the eradicating of trachoma by the year 2020 has been set up. In Africa, the situation remains critical in spite of significant improvements in the training of eye care personnel and the implementation of new eye care facilities. If no additional action is taken, the number of blind from cataract will steadily increase, mainly because of population growth and aging. Substantial further efforts should be made to make appropriate eye care accessible and affordable to all those in need.

[World Health Organization alliance for the elimination of trachoma]. / L'alliance de l'Organisation Mondiale de la Santé pour l'élimination du trachome.

Although trachoma has either decreased or disappeared in many Third World countries through socio economic development during the past forty years, it remains a major problem among the poorest communities, which is often ignored by decision-makers when setting priorities. Fortunately, recent developments will allow to overcome many of the past obstacles and to offer new opportunities for trachoma control programmes. WHO aware of this new favourable context for trachoma control has taken the leadership in mobilizing and coordinating trachoma control efforts through the creation of a WHO Alliance for the Global Elimination of Trachoma. The aim of this Alliance is to assist Member States where trachoma is endemic achieve the goal of (global) elimination of trachoma by the year 2020. This is indeed possible through the combination of various interventions such as those proposed by the SAFE strategy (Surgery for trichiasis, Antibiotics, Face washing and Environmental changes) recommended by WHO. The prevention of trachoma and its treatment will rely largely on the efforts made by the endemic countries concerned with this problem. Therefore, new and or existing trachoma control programmes should be either implemented or strengthened at community-based level within the framework of the available primary health care systems based on the application of the SAFE strategy and on the assistance of the Alliance partners.

The WHO programme for the prevention of deafness and hearing impairment.

The WHO Programme for the Prevention of Deafness and hearing Impairment (PDH) was established in 1987 to deal with causes of avoidable hearing loss, particularly in developing countries. The Programme is developing its strategies on the basis of essential ear care as part of primary health care, and the collection of epidemiologically sound data on ear disease and hearing impairment. A uniform Ear Examination Form is being finalized, for use in field surveys. The PDH Programme suffers from not having adequate resources available, and few countries have so far taken on the prevention of deafness as a health care issue. In the Eastern Mediterranean, South-East Asia and Western Pacific Regions, a number of national programmes will hopefully develop in the near future. Particular issues for the next two years include ototoxicity and the management of otitis media. Overall, the priority is to obtain programme staff and a more adequate working budget.