A new survey of blindness and low vision in Nigeria of adults aged 40 and above has found that nearly half a million adults in Africa’s most populous country are in immediate need of cataract surgery.
Initiated by the Federal Ministry of Health, the survey was supported by Sightsavers International and provides important data which had previously been lacking about the number of people in Nigeria who are blind and visually impaired and the causes of their visual loss.
The survey indicates that 486,000 adults across the country are in immediate need of cataract surgery, a straightforward operation lasting a matter of minutes, which the World Bank has described as “one of the most cost-effective surgical interventions”. Other important causes of blindness were glaucoma (a condition in which the optic nerve is damaged, often by high pressure inside the eye), corneal scarring and poor procedures for cataract surgery. Onchocerciasis, or river blindness, and trachoma together accounted for five percent of blindness.
The survey found that almost half of all procedures for blinding cataract undergone by survey participants had been performed by herbalists (“couching”) and this was more common in the north of the country. During couching an instrument is used to dislocate the opaque lens away from the pupil, into the back of the eye but this is often associated with complications.
As in many developing countries, Nigeria suffers from a lack of trained staff and equipment to enable a significant reduction in the backlog of cataract operations. In this part of Africa, the number of ophthalmologists is less than one per million people.
Extrapolating the data from the survey to the total population, the prevalence of blindness in Nigeria is estimated to be 0.78%.
The survey’s other key preliminary findings are as follows:
– In Nigeria, over 1,000,000 adults are blind and another 3,000,000 are visually impaired
– 42 out of every 1000 adults aged 40 and above are blind
– Overall, two out of three Nigerians are blind from causes which could be avoided such as cataract which is the single commonest cause of blindness
– Blindness is almost three times more common in the dry northern areas (the Sahel) than in southern delta areas
– Illiterate participants were twice as likely to be blind as those who were literate
During the survey, information was also collected on non-communicable diseases such as diabetes, hypertension and obesity, and also on measures of development, such as access to safe water and sanitation, and levels of literacy.
Sightsavers has been working to prevent and cure blindness in Nigeria for over 40 years as well as support people who are permanently blind and visually impaired. According to the organisation’s representative in Nigeria, Dr Elizabeth Elhassan:
“Nigerians now account for one in five Africans and the survey indicates the growing and urgent need to increase access to eye care as well as the importance of reaching people who are illiterate.”
An additional benefit of the survey is that the findings are applicable to almost 100 million people who live in surrounding countries that share similar ecological zones to Nigeria such as Benin, Togo and Niger.
Professor Clare Gilbert from the International Centre for Eye Health and medical advisor to Sightsavers was closely involved with the survey. “The information from this national survey,” she said, “will prove invaluable in the planning of comprehensive eye services in Nigeria and elsewhere, from prevention and rehabilitation in the community through to tertiary level clinical services.”
As a direct result of the survey, over 3500 cataract operations were performed, 5800 pairs of reading glasses dispensed, more than 200 pairs of aphakic glasses distributed at no cost and thousands with minor ailments were treated.
1. The Nigerian National Survey of Blindness and Low Vision examined over 13,600 adults aged 40 years and over in 305 clusters across the country. Every state had at least three clusters. Over 5000 children aged 10-15 years were also examined. A total of 140 staff conducted the survey using the latest equipment, including visual field testing and digital photography. Field work took place between 2005 and 2007.
2. The survey was supported by Sightsavers International (UK), CBM (Germany), The Velux Stiftung (Switzerland), state governments and the FCT Abuja, local governments and the Federal Ministry of Health (Nigeria). Copies of the survey’s preliminary findings are available.
3. There are 45 million blind people in the world; 75% of all blindness can be prevented or cured.
4. Sightsavers International is a registered UK charity (number 207544 England & Wales, Scotland SC038110) that works in more than 30 developing countries to prevent blindness, restore sight and advocate for inclusion and equal rights for people who are blind and visually impaired.