Blindness and vision impairment
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`Blindness and vision impairment
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`Credits
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`10 August 2023
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`Key facts
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`Globally, at least 2.2 billion people have a near or distance vision impairment. In at least 1
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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
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`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 1
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`Blindness and vision impairment
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`billion of these, vision impairment could have been prevented or is yet to be addressed.
`The leading causes of vision impairment and blindness at a global level are refractive errors
`and cataracts.
`It is estimated that globally only 36% of people with a distance vision impairment due to
`refractive error and only 17% of people with vision impairment due to cataract have
`received access to an appropriate intervention.
`Vision impairment poses an enormous global financial burden, with the annual global cost
`of productivity estimated to be US$ 411 billion.
`Vision loss can affect people of all ages; however, most people with vision impairment and
`blindness are over the age of 50 years.
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`Overview
`Vision, the most dominant of our senses, plays a critical role in every facet and stage of our lives. We take
`vision for granted, but without vision, we struggle to learn, to walk, to read, to participate in school and
`to work.
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`Vision impairment occurs when an eye condition affects the visual system and its vision functions.
`Everyone, if they live long enough, will experience at least one eye condition in their lifetime that will
`require appropriate care.
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`Vision impairment has serious consequences for the individual across the life course. Many of these
`consequences can be mitigated by timely access to quality eye care. Eye conditions that can cause vision
`impairment and blindness – such as cataract or refractive error – are, for good reasons, the main focus
`of eye care strategies; nevertheless, the importance of eye conditions that do not typically cause vision
`impairment – such as dry eye or conjunctivitis – must not be overlooked. These conditions are frequently
`among the leading reasons for presentation to eye care services.
`Causes
`Globally, the leading causes of vision impairment and blindness are:
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`refractive errors
`cataract
`diabetic retinopathy
`glaucoma
`age-related macular degeneration.
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`There is substantial variation in the causes of vision impairment between and within countries according
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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
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`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 2
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`Blindness and vision impairment
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`to the availability of eye care services, their affordability, and the education of the population. For
`example, the proportion of vision impairment attributable to unoperated cataract is higher in low- and
`middle-income countries. In high income countries, diseases such as glaucoma and age-related macular
`degeneration are more common.
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`Among children, congenital cataract is a leading cause of vision impairment in low-income countries,
`whereas in middle-income countries it is more likely to be retinopathy of prematurity.
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`Uncorrected refractive error remains a leading cause of vision impairment in all countries amongst
`children and adult populations.
`Prevalence
`Globally, at least 2.2 billion people have a near or distance vision impairment. In at least 1 billion – or
`almost half – of these cases, vision impairment could have been prevented or has yet to be addressed.
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`Among this 1 billion people, the main conditions causing distance vision impairment or blindness are
`cataract (94 million), refractive error (88.4 million), age-related macular degeneration (8 million),
`glaucoma (7.7 million), diabetic retinopathy (3.9 million) (1). The main condition causing near vision
`impairment is presbyopia (826 million) (2).
`
`In terms of regional differences, the prevalence of distance vision impairment in low- and middle-income
`regions is estimated to be 4 times higher than in high-income regions (1). With regards to near vision,
`rates of unaddressed near vision impairment are estimated to be greater than 80% in western, eastern
`and central sub-Saharan Africa, while comparative rates in high-income regions of North America,
`Australasia, western Europe, and of Asia-Pacific are reported to be lower than 10% (2).
`
`Population growth and ageing are expected to increase the risk that more people acquire vision
`impairment.
`Impact of vision impairment
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`Personal impact
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`Young children with early onset irreversible severe vision impairment can experience delayed motor,
`language, emotional, social and cognitive development, with lifelong consequences. School-age children
`with vision impairment can also experience lower levels of educational achievement.
`
`Vision impairment severely impacts quality of life among adult populations. Adults with vision
`impairment can experience lower rates of employment and higher rates of depression and anxiety.
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`In the case of older adults, vision impairment can contribute to social isolation, difficulty walking, a
`higher risk of falls and fractures, and a greater likelihood of early entry into nursing or care homes.
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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
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`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 3
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`Blindness and vision impairment
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`Economic impact
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`Vision impairment poses an enormous global financial burden with an estimate annual global
`productivity loss of about US$ 411 billion purchasing power parity (3). This figure far outweighs the
`estimated cost gap of addressing the unmet need of vision impairment (estimated at about US$ 25
`billion).
`Strategies to address eye conditions to avoid vision
`impairment
`There are effective interventions covering promotion, prevention, treatment and rehabilitation which
`address the needs associated with eye conditions and vision impairment. While many vision loss cases
`can be prevented (such as those due to infections, trauma, unsafe traditional medicines, perinatal
`diseases, nutrition-related diseases, unsafe use or self-administration of topical treatment), this is not
`possible for all. For many eye conditions, e.g. diabetic retinopathy, early detection and timely treatment
`are crucial to avoid irreversible vision loss. Spectacle correction for refractive error and surgery for
`cataract are among the most cost-effective of all health-care interventions. Yet, globally only 36% of
`people with a distance vision impairment due to refractive error have received access to an appropriate
`pair of spectacles and only 17% of people with vision impairment or blindness due to cataract have
`received access to quality surgery.
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`Treatment is also available for many eye conditions that do not typically cause vision impairment, such as
`dry eye, conjunctivitis and blepharitis, but generate discomfort and pain. Treatment of these conditions
`is directed at alleviating the symptoms and preventing the evolution towards more severe stages of
`those diseases.
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`Vision rehabilitation is very effective in improving functioning for people with an irreversible vision loss
`that can be caused by eye conditions such as diabetic retinopathy, glaucoma, consequences of trauma,
`and age-related macular degeneration.
`WHO response
`WHO’s work is guided by the recommendations of the WHO World report on vision (2019) and the
`resolution on "integrated, people-centred eye care, including preventable blindness and vision
`impairment" adopted at the Seventy-third World Health Assembly in 2020. The key proposal is to make
`integrated people-centred eye care (IPEC) the care model of choice and to ensure its widespread
`implementation. It is expected that by shaping the global agenda on vision and eye care, the report and
`resolution will assist Member States and their partners in their efforts to reduce the burden of eye
`conditions and vision.
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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
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`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 4
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`Blindness and vision impairment
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`Some of WHO’s key areas of work and activities in the prevention of blindness include:
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`1. Working with Member States and other partners in the field to monitor the global targets for 2030 on
`integrated people-centred eye care:
`Developing reports of the effective coverage of eye care indicators to monitor progress towards
`the 2030 global targets.
`Developing resources and technical tools to support the integration of eye care into health
`information systems.
`2. Observing and promoting World Sight Day as an annual advocacy event.
`3. Supporting the integration of eye care in health systems through the implementation of a series of
`technical tools:
`The Eye care in health systems: Guide for action.
`The Package of eye care interventions (PECI).
`The Eye care competency framework (ECCF).
`4. The development and implementation tools to support countries to assess the provision of eye care
`services such as:
`The Eye care situation analysis tool
`The Tool for the assessment of diabetic retinopathy and diabetes management services.
`The Tool for the assessment of glaucoma services.
`The Tool for the assessment of refractive services.
`The Tool for the assessment of rehabilitation services and systems.
`5. The development of materials and resources to raise awareness on eye care:
`The MyopiaEd: a mobile health toolkit for myopia to increase health literacy.
`A population-facing app for near and distance visual acuity testing.
`Graphics promoting healthy eye habits.
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`References
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`1. GBD 2019 Blindness and Vision Impairment Collaborators; Vision Loss Expert Group of the Global
`Burden of Disease Study. Causes of blindness and vision impairment in 2020 and trends over 30 years,
`and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the
`Global Burden of Disease Study. Lancet Glob Health. 2021 Feb;9(2):e144-e160. doi: 10.1016/S2214-
`109X(20)30489-7.
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`2. Fricke, TR, Tahhan N, Resnikoff S, Papas E, Burnett A, Suit MH, Naduvilath T, Naidoo K, Global
`Prevalence of Presbyopia and Vision Impairment from Uncorrected Presbyopia: Systematic Review,
`Meta-analysis, and Modelling, Ophthalmology. 2018 May 9.
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`3. Burton MJ, Ramke J, Marques AP, Bourne RR, Congdon N, Jones I, et al. The Lancet Global Health
`commission on Global Eye Health: vision beyond 2020. Lancet Glob Health. 2021; 9(4):e489–e551.
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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
`
`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 5
`
`

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`Blindness and vision impairment
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`Related
`
`Health topic page
`
`WHO’s work on eye care, vision impairment and blindness (who.int)
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`Related links
`
`Report of the 2030 targets on effective coverage of eye care (who.int)
`Eye care in health systems: guide for action (who.int)
`World report on vision (who.int)
`
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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
`
`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 6
`
`

`

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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
`
`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 7
`
`

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`https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment[1/24/2024 6:29:45 PM]
`
`Samsung et al. v. Regeneron IPR2023-00884
`Regeneron Pharmaceuticals, Inc. Exhibit 2239 Page 8
`
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