Press Release WHO/34
17 April 1998
THE CONTROL OF RIVER BLINDNESS:
THE LEOPARD MUST CHANGE ITS SPOTS
One of the most successful health and development projects in Africa is now winding down. The Onchocerciasis Control Programme in West Africa (OCP)*, sponsored by the World Bank, the United Nations Development Programme, the UN Food and Agriculture Organization and the World Health Organization (WHO) - with WHO its Executing Agency - will terminate in 2002.
It will have protected over 40 million people from the disease, including some 600 000 persons prevented from blindness. It has permitted 25 million hectares of fertile land to be reclaimed for food production, enough to feed 17 million persons each year. Gone are the days when up to 50% of the adult population over 30 years of age in rural areas of Western Africa suffered from what was known as "the disease at the end of the road".
But OCP leaves behind a dangerous enemy, ready to reinfect the protected areas and destroy over 25 years of hard work and a half-billion dollars of investment. For not all of Africa has yet been freed from onchocerciasis and the black flies which transmit the disease still infest the zones in West Africa already freed from the disease. These flies can again become transmitters, either by infected flies moving into the area, or by uninfected flies biting infected persons who have moved into the region.
Surveillance to detect reinfection and rapid protection of the concerned population by treatment with ivermectin is required, and must be maintained for the foreseeable future.
Yet surveillance for onchocerciasis alone does not make managerial or economic sense. "How do you convince people to look for a disease which is no longer a problem?" says Dr Ebrahim Samba, WHO Regional Director for Africa, himself a veteran of the onchocerciasis campaign. "You must integrate this surveillance into a multi-disease surveillance system primarily oriented towards epidemic-prone diseases such as cholera, meningitis, yellow fever and malaria."
So the leopard which was the OCP must now change its spots and evolve from a one-disease control operation into a multi-disease surveillance system. How to do this was the challenge addressed this week in Ouagadougou, Burkina Faso, home to OCP, by health officials and epidemiologists from eleven West African countries**, together with WHO staff and OCP personnel as well as representatives of the World Bank and nongovernmental organizations.
They used as an overall framework the Regional Strategy for Integrated Disease Surveillance in Africa developed by the WHO Regional Office for Africa.
OCP has a unique infrastructure, including a sophisticated software computer programme mapping all villages in West Africa, an up-to-date disease data bank, permanent radio communications within the eleven participating countries, a network of epidemiological teams and entomological centres and laboratories and a fleet of 200-plus vehicles. The World Health Organization and its Regional Office for Africa are proposing the creation, in place of OCP, of a subregional watchdog patrolling the area for signs of outbreaks and epidemics of infectious diseases. The new body is to use the infrastructure established by OCP for epidemiological surveillance of onchocerciasis as well as other infectious diseases.
The difficulties are numerous. "Nobody has all the answers", says Dr Ralph Henderson, WHO Assistant Director-General. "We have to work step by step, adapting to the special needs of each country. But the difficulties must be overcome. Otherwise onchocerciasis will return to blight the lives of future generations in West Africa."
*Onchocerciasis or river blindness is transmitted by the bite of the black fly. The disease is caused by the release into the blood stream of tiny worms (microfilaria) by mature adult worms (macrofilaria). These tiny worms cause unbearable itching, skin disfiguration and blindness. The microfilaria can be treated with ivermectin. Treatment must be maintained for some 15 years until the adult worms die.
** Benin, Burkina Faso, Cote d'Ivoire, Ghana, Guinea, Guinea Bissau, Mali, Niger, Senegal, Sierra Leone and Togo.
For further information please contact Valery Abramov, Health Communications and Public Relations, WHO, Geneva. (Tel. (41 22) 791 2543, Fax (41 22) 791 4858. Email email@example.com.
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