September 2000


Once described as an ancient scourge, river blindness - a devastating disease that is the third leading cause of blindness in Africa - is finally being tamed.

By Lewis Machipisa

As a result of the success of the Onchocerciasis Control Programme (OCP), which began in 1975, some 12 million children born since the operations will have grown up without the risk of infection by river blindness.

Villages once deserted as a result of onchocerciasis (or, as it is more commonly known, river blindness) are now flourishing, and children once resigned to darkness are now growing up free from the debilitating condition for the first time, able to look toward the future.

According to Gro Brundtland, the World Health Organisation’s Director-General, as a result of the successful operation of the programme over the past 25 years, 25 million hectares of fertile land deserted for fear of the disease have now been cleared and are now available for cultivation. That is enough to feed 17 million people per year.

Often, the most fertile, arable lands, lying around the rapid flowing rivers that provide the breeding sites for the blackfly vector, which carries the disease, would be deserted because of widespread fear of the disease.

Before the OCP was established in 1974, river blindness affected more than one million people in West Africa. At least 10,000 people had serious eye problems, including 35,000 who were blinded by the disease, WHO says in a statement.

WHO says it is now close to eliminating the disease as a public health problem in 11 countries - Benin, Burkina Faso, Cote d’Ivoire, Ghana, Guinea, Guinea Bissau, Mali, Niger, Senegal, Sierra Leone and Togo - where the sickness is endemic.

In the south, the disease is found in Angola and Malawi. In the rest of the world, it is found in small pockets in Yemen and in Central and South America.

About 85 million people were at risk of infection worldwide, WHO estimated in 1987. Eighteen million were infected, one million had sight problems and 350,000 were blind.

‘Today, there are hardly any infections within the original area of OCP operations and vector control efforts have almost ceased,’ says WHO.

Today, according to WHO, about 1.5 million people who were infected with river blindness no longer have any trace of the disease. By the turn of the century, it is estimated that the programme will have prevented almost 300,000 cases of blindness in the 11 countries involved in the programme.

The disease’s villain is a repulsive worm called onchocerca volvulus and its partner-in-crime, the tiny but aggressive hump-backed blackfly, which carries the disease from one person to the next.

After they enter the skin of a human through the bite of an infected female blackfly, the parasites mature from larvae into threadlike adult male and female worms which live in nodules - ugly bumps - under the skin.

The females can grow to 50 centimetres in length, while the much thinner males may grow to a mere 5 centimetres. These adult worms mate, giving birth to millions of infant worms. The females may live for as long as 14 years.

The infant worms escape through the walls of the nodules and migrate to all parts of the human body - they have been found in tears, sputum, urine, and vaginal secretions. They may either die after living for up to 30 months, or be ingested by a female blackfly when she needs a meal of blood and then, after evolving into another stage, be taken off to be transmitted to another human when the blackfly takes another meal. The cycle of misery continues.

The infant worms in the human body cause havoc. Their presence and death cause rashes and itching. Over the years the skin becomes swollen and thickened, and there is often depigmentation, leaving white patches.

Sometimes there is genital swelling, loss of weight, and debilitation. But the worst is yet to come. With repeated infections over the years, the disease becomes more and more severe. Eventually the infant worms get into the eyes and, with their deaths, cause ‘chronic sclerosing keratotis’. In other words, the victim goes blind.

In a publication - titled And They Forgot to Tell Us Why - that looks at the campaign against river blindness in West Africa, the World Bank details the negative impact of the disease on economic and social development as communities migrated to overpopulated, arid regions.

According to the book, authored by researcher David Wiggs, the OCP is a model of ‘what can happen when development works as it should’.

‘Moreover, the campaign against river blindness shows how a major international cooperative effort can change the lives of millions of people in the developing world by stepping beyond the confines of narrow, short-term self-interest and accepting a broader, global responsibility,’ says the World Bank.

The WHO, the World Bank, the United Nations Development Programme (UNDP) and the Food and Agriculture Organisation (FAO) have been co-sponsors of the OCP since 1975.

In the WHO statement, Brundtland paid tribute to Ebrahim Samba, WHO’s regional director for Africa, who spent 14 years of his life fighting to drive back river blindness. - Third World Network Features/IPS

·        About the writer: Lewis Machipisa works with the Inter Press Service in Harare, Zimbabwe. The above article is reprinted with the permission of IPS.