Definition and Causes
Blindness is the inability to see. The leading causes of chronic blindness include cataract, glaucoma, age-related macular degeneration, corneal opacities, diabetic retinopathy and eye conditions in children (e.g. caused by vitamin A deficiency). Age-related blindness is increasing throughout the world, as is blindness due to uncontrolled diabetes. On the other hand, blindness caused by infection is decreasing, as a result of public health action. Three-quarters of all blindness can be prevented or treated.
Action Plan 2014-2019
Action plan for the prevention of avoidable blindness and visual impairment for 2014-2019. The 66th World Health Assembly endorsed Universal eye health: a global action plan 2014–2019.
The magnitude of visual impairment and blindness and their causes have been estimated, globally and by WHO region from recent data. For countries without data estimates were based on newly developed model. Globally the number of people of all ages visually impaired is estimated to be 285 million, of whom 39 million are blind. People 50 years and older are 82% of all blind. The major causes of visual impairment are uncorrected refractive errors (43%) and cataract (33%); the first cause of blindness is cataract (51%). Visual impairment in 2010 is a major global health issue: the preventable causes are as high as 80% of the total global burden.
Visual impairment often limits people’s ability to perform everyday tasks and affects their quality of life. Blindness, the most severe form of visual impairment, reduces people’s ability to move about unaided unless properly trained.
Action plan 2014-2019
Investing in eye health: securing the support of decision-makers
285 million people have visual impairment: the support of policy-makers to address the burden of impaired vision is essential