Onchocerciasis control in Ghana: achievements and Prospects after OCP

'* ONCHOCERCIASIS CONTROL IN GHANA Achievements and Prospects after OCP 2002 2I. INTRODUCTION Onchocerciasis in West Africa before OCP . Onchocerciasis prevails in Africa, America and in the Arabian peninsula. . It was estimated that in the world: Approximately 122,9 million people were exposed to onchocerclasls. More than 17,7 million people were infected with the disease. More than2lO 000 people were blind and at least 500,000 had visual impairment cased by onchocerciasis. Africa is the continent most affected, with more than 16.9 million (95%) victims. West Africa was not only particularly affected but most of all it had the most significant foci of the most serious form of the disease. These foci were located particularly in the northern parts of Benin, Togo, C6te d'Ivoire, Ghana, east of Mali, the south of Niger and were disseminated in the whole of Burkina Faso. It is in these areas known as the original area, covering 654,000km2 that the Onchocerciasis Control Programme in West Africa (OCP) was started. The Programme then extended to the foci south of C6te d'Ivoire, Benin, Togo and Ghana, then to the west of Mali, Guinea, Guinea-Bissau, Senegal and Sierra Leone. Today, the whole of the Programme area covers 1 235 000 km2 with almost 40 million people. Before the beginning of the control operations, there existed more than 3 million onchocercal patients out of which approximately 135,000 were blind. Onchocerciasis is a parasitic disease. It is caused by a filarial (a worm) known as Onchocerca volvulus. The adult worrn which develops only in man produces microfilariae which is transmitted to other men by the bite of a tiny fly commonly called "simulie", the vector of the disease. Onchocerciasis prevails only in rural areas, in the settlements located along the rivers with fast flowing current. The simulie reproduces in these rivers, hence the name "river blindness" which is still interchanged with the name onchocerciasis. The most exposed communities are those located approxirnately ten kilometres on both sides of the rivers. Blindness, the nuissance and other consequences of onchocerciasis are factors for the deterioration of the living conditions of these communities and the cause of tlie abandonment of the fertile riverain lands by the villagers. An agreement signed in 1973 between tlie parlicipating govermnents and WHO det-uted the limits, the objectives, the of consultative structures and management of the Programme as well as the rnodalities for control operations and evaluation procedures. After approval of the mission report of the "support Prograt-ume to Govemtrents" itt Janrrary 1974,tbe budget necessary for the irnplementation of the onchocerciasis cotrtrol programme in the Volta basin was voted. WHO u'as then designated as the Execr.rting Agency. In a fit of intemational solidartty,.22 countries and instituttorts tlnanced the activities of OCP for nearly three decades. 1.1 I I 31.2. Control Strategies used The main strategy used is vector control to which ivermectin treatment was added in 1987. In certain areas, vector control was the method used and in others ivermectin treatment only. In some others on the other hand, the two strategies were combined. 1.3. Results obtained in the OCP area Onchocerciasis is now eliminated as a problem of public health in all the OCP area. In some limited foci however, there is the need to improve on the results achieved. Nearly 40 million people are protected today from onchocerciasis and more than 18 million children bom since the beginning of the Programme have escaped the risk of onchocercal blindness. ! 600,000 cases ofblindness have been prevented Presently, more than 25 million hectares of riverain lands have been redeemed and is being re-populated and developed. This will enable about 17 million people to be nourished. It is to be noted however that, at some points, the results need to be improved. These are the tributaries of the Oti in Togo, the Ou6m6 in Benin, the Pru in Ghana" the Mafou and the Tinkisso in Guinea. 1I. ONCHOCERCIASIS IN THE REPUBLIC OF GHANA BEFORE OCP Ghana is one of seven first countries of OCP to start onchocerciasis control. Onchocerciasis has been endemic in all parts of the country; Northern, Upper East, Upper West, Volta, the Southern districts of Brong Ahafo and Ashanti Region, Western and Central Regions except the Greater Accra Region. Blindness rate was up to 3.8 o/o in certain areas. The prevalence was very high: 54 to 84 o/o and the Community Microfilarial Load (CMFL) was between 10 and 25 rnicrofilaria per snip. The Annual Biting Rate (ABR) was high,29790 and the Annual Transmission Potential (ATP) was between 0 and 1637. Control activities were formerly limited to the endemic areas of the northern half of the country i.e. Northern, Upper East, Upper West and parts of the Brong Ahafo Region. The control activities have been periodically extended to include the northern fringes of the forest zone that is southern parts of the Brong Ahafo, Ashanti, Eastern, Westem and the Volta Region where the non-blinding type of the disease exists with associated psychosocial and economic losses. I 4III. STRATEGIES 3.1 . Vector control The main strategy was concentrated on larviciding to eliminate the fly at the larval stage of its life cycle. The aerial larviciding started tn 1976 in the northern part of the country on theVolta basin and its tributaries of Kulpawn, Mole and Daka. In 1988 it was extended to southern part on the Pru river. 3.2. IvermeStlulrc In 1987 ivermectin was introduced into the Programme as a microfilaricide. This is now the main thrust of the control activities, aerial larviciding having been stopped in most of the river basins as a result of satisfactory results. At the beginning, the drug was distributed by health teams composed of OCP staff and nationals through mobile means. Today this activity is carried out by the communities themselves through Community distributors in more than 2800 villages. 3.3. The trainine of nationals To ensure the sustainability of the achievements by the Participating Countries, OCP (in collaboration with National Authorities) undertook training of the nationals at the academic level as well as on-the-job trainings. 3.4. Other strateqies Information, Education and Comrnunication (IEC), epidemiological and entomological surveillance are also other strategies used for oncho control. IV. RESULTS IN 2OO2 4.1 Sienificant ts in Ghana Land has been recovered from the endemic zones of Upper West, Upper East and Northem Region for agricultural activities and socio-economic development. Children under 20 years are not at risk ofthe disease. Epideniiolo sical results The prevalence rates have dropped to less than 5 7u in several basins. For example the prevalence dropped from 72.6 to 4 oh in some areas on the White Volta basin arld from 68.8 to 8.4% on tlie Black Volta basin. The CMFL is lower than I microhlariaeisrlip in several river basins. There are sotne areas which continue to have prevalence rates above 30% inspite of vigorous control efforts. These arc the trouble areas rvhich need special sun'eillance. 5Entomolosical results The ATP rate is 0 in several basins except in the Pru basin where it is around 140 (the target is < 100). The ABR rate has dropped and is less than 700. CDTI results Therapeutic and Geographical coverage targeted at 65+ and 100% respectively are not being achieved. The therapeutic coverage for 2000 has dropped from 63.8% to 50.5%. Training results A total of 44 people in Ghana have benefited from OCP fellowship, 10 in entomology,14 in epidemiology, 4 in parasitology, 4 in hydrobiology, 2 in ophthalmology, 2 it management, 4 in administration and 1 in public health. Some Medical Officers and nurses and other Health Workers in the endemic zones have been trained on the oncho control strategies as well as some community members as Community Distributors for the CDTI implementation. V. OBSERVATIONS (a) CDTI The Drug Mectizan is ordered directly from Mectizan Donation Programme (MDP) with assistance of UNICEF/Ghana. Though there is a good drug Supply System in place, there are problems of communication and administration difficulties which delay the distribution at the community level. A workshop on ivermectin management has been organised for Regional Pharmacists and Medical Store personnel. Regional Pharmacists are:- in-charge with collaboration of the Chief Pharmacist. Returns and data anal_vsis Returns have been very slow with long delays in submission Epidemiolo eical Surveillance Regional teams are in place to carry out this activity but it is expensive. This is: (b) rec Implemented at regional level as part of routine IEC activities. National level collaborates TV emissions on IEC on oncho. (c) ENTOMOLOGY Trained entomologists, technicians and other auxiliaries have been identified to carry out sun'eillance activities a a VI. CONDITIONS TO SUSTAIN AND IMPROVE ACHIEVEMENTS QDfl to achieve 100 7o eeoeraphical and at least 65 70 therapeutic coverase Retraining of CDDs Provide incentives to Health staff at Sub-district level Provide motivation in kind to CDDs Increase period of holding of drugs by CDDs Annual National Meeting on CDTI after treatment period ,a 6Strengthen monitoring at sub district level. Epidemiolo sical Surveillance - Facilitate release of Regional teams. - IEC in areas where prevalence is 0%. - Provision of Financial Support from National level to the regions Entomoloeical Surveillance - Entomological surveillance in the Pru river basin to evaluate the efficacy of larviciding will have to continue for some time. There is therefore the need to maintain the entomological team at Kintampo. - Entomological surveillance will have to be conducted in the eastern part of the Volta Lake, specifically, at Dodi Papase on river Asukawkaw and at Wegbe on river Dayi, (where larviciding have just ceased) to justiS the cessation of larviciding. - Entomological surveillance will also be mounted in an area in Northern Ghana which is on ivermectin distribution to determine the impact of the distribution of the drug on the transmission. - There is therefore the need to have enough funds to enable these activities to go through. Data management There is need for retraining of the sub-district staff at District level Ensuring regular maintenance of computer. Mobilization of required financial resources Sustenance of budget line for oncho control Hold partners' meeting Availability of human resources.