The study published in the Lancet Global Health on 2 August shows that blindness affects 36 million people globally, with developing countries bearing the greatest burden.
Kovin Naidoo, a co-author of the study and founder of the African Vision Research Institute, University of Kwazulu-Natal, South Africa, says that “growth and ageing of the world’s population is causing substantial increase in number of people affected”.
The researchers, who form the Vision Loss Expert Group, an international network of eye care specialists, conducted a systematic review and meta-analysis of population-based datasets relevant to global vision impairment and blindness published between 1980 and 2015. They retrieved 3,878 papers but analysed 61 to arrive at their findings.
“The findings are relevant to people serving the needs of the blind and visually impaired including educationists and training institutions.”
The researchers estimated the prevalence of eye disorders such as blindness and visual impairment in 2015, compared it with the figures in 1990 and made projections for 2020 and 2050.
They found that in 2015 the prevalence of blind in adults was highest in the world’s developing world compared with the developed regions, with Sub-Saharan Africa and South Asia hardest hit. For example, whereas developed regions had older adults blindness prevalence of less than one per cent, that of West Africa was five per cent, and East Africa and South Asia were about four per cent each.
Source: Rupert R. A. Bourne and others
“We projected that an estimated 38·5 million people would be blind in 2020 (of a total global population of 7·75 billion) and 114·6 million people would be blind in 2050 (of a total global population of 9·69 billion),” the authors report.
Vision impairment, defined as a limitation of one or more functions of the eye, also disproportionally affected the developing regions.
The study indicates about 55 per cent of all visually impaired people worldwide are women, and that 89 per cent of those who are visually impaired live in low- and middle-income countries.
Credit: International Agency for the Prevention of Blindness
Blindness and vision impairment are increasing with the aging population because populations are living longer due to improvements in healthcare and technological advances, Naidoo tells SciDev.Net.
“There is currently a dire need for human resources in these areas to address the needs,” says Naidoo. “However, if the population growth continues as it is predicted, the potential economic impact will be significant since people are unable to be productive or younger people are taking care of people with blindness and vision impairment.”
The study, Naidoo notes, highlights that the efforts made between 1990 and 2010 such as community eye care services, and focusing strategically on eye diseases, especially on cataracts and uncorrected refractive errors, have made a significant impact on alleviating blindness and vision impairment.
“The findings are relevant to people serving the needs of the blind and visually impaired including educationists and training institutions, civil society organisations, politicians, eye care advocates, ministries of health and the WHO,” Naidoo says. Andrew Bastawrous, assistant professor in international eye health at the London School of Hygiene and Tropical Medicine, United Kingdom, says prevalence of blindness has been steadily decreasing for the last 25 years because of strategic focus on diseases that make the greatest difference to highest number of people: cataracts and uncorrected refractive errors.
He calls for lowering the barriers to access services and strengthening health systems to prevent billions of people from unnecessary sight loss.
According to Bastawrous, addressing blindness requires use of advanced technology to provide high-quality, data-driven, human-centred solutions; establishment of public-private partnership and creation of new financing models that incentivise impact and continuous improvement.
Bastawrous adds that governments need to prioritise good vision for all the population, help develop novel treatments, and boost research to understand the barriers and solutions in a wide variety of systems.
Factors contributing to low access of eye health services
|Awareness||On both a policy and individual level, there is a lack of awareness that curative or preventative treatments exist and are available.|
|Bad Services||High pressures on services can often lead to a poor reputation. Even when an alternative is available or services improve, poor reputation remains a barrier.|
|Cost||Direct (cost of treatment, insurance) and indirect costs (travel, time away from home) are often prohibitive to receiving treatment in low-income communities|
|Distance||The travel logistics and time required to reach a treatment facility are often too great to enable access to those most in need of services.|
|Escort||Provision for a carer who will escort a person with sight-impairment is often overlooked, for example, there is no space on the outreach bus or hospital accommodation for the escort.|
|Fear||A lack of effective counselling and investment in education leads to many potential beneficiaries holding beliefs that leave them fearful of the treatment they will receive.|
|Gender||All of the above barriers effect women and girls more than men and boys|
This piece was produced by SciDev.Net’s Sub-Saharan Africa English desk.