About 1.1 billion people live with vision impairment, most of it preventable or treatable with cataract surgery or a pair of glasses, yet only about half of older adults who need cataract surgery get a good result from it and the 2030 coverage targets are far out of reach.
Written from the sources listed below, not independently peer-reviewed.
How many people worldwide had blurred near vision in 2020 simply because they did not have reading glasses?
1.1 billion
People with distance vision impairment or uncorrected near vision
Modelled estimate for 2020, including 43 million people who are blind and 510 million with near vision impairment that reading glasses could correct. More than 90% have a preventable or treatable cause.
Data year 2020. Source: Burton M.J. et al., The Lancet Global Health 9(4):e489–e551, 2021
48%
Effective cataract surgical coverage, adults 50+
Share of older adults needing cataract surgery who have had it with a good result (48.2%, modelled from 233 surveys in 68 countries). In the WHO African Region the figure is 23.6%.
Data year 2025. Source: McCormick I. et al., 2026
66%
Effective refractive error coverage, adults 50+
Share of older adults needing distance correction who have it and see well with it (65.8%, modelled from 237 surveys in 76 countries). Ranges from 84.0% in high-income countries to 28.3% in sub-Saharan Africa.
Data year 2023. Source: Bourne R.R.A. et al., 2025
Unit: % of people needing cataract surgery operated with a good result
* Projection, not a measurement. Modelled estimates from 233 population-based surveys in 68 countries (2003–2024), using a good outcome threshold of 6/18; 2030 is a projection at the current pace. Wide uncertainty ranges (2025: 39.7–57.2%), and Europe could not be modelled for lack of data.
In 2021 WHO member states endorsed two global targets for 2030: a rise of 30 percentage points in effective cataract surgical coverage and of 40 percentage points in effective refractive error coverage. A 2026 study projects that cataract coverage will rise by only 8.4 percentage points between 2020 and 2030, and by 4.0 points in the WHO African Region. For glasses, a 2025 study found that none of the 16 countries with more than 100 million people is on track to meet the refractive error target.
Among adults aged 50 and over who need distance glasses, 84.0% in high-income countries have effective correction, against 28.3% in sub-Saharan Africa (2023).
Source: Bourne R.R.A. et al., 2025Women make up about 55% of the 43.3 million people who are blind and of the 510 million with uncorrected near vision (2020 estimates).
Source: GBD 2019 Blindness and Vision Impairment Collaborators and Vision Loss Expert Group, The Lancet Global Health 9(2):e130–e143, 2021In the WHO African Region, effective cataract surgical coverage in 2025 was estimated at 20.2% for women and 26.9% for men, the only region where the gap between the sexes was statistically clear.
Source: McCormick I. et al., 2026More than 80% of near vision impairment goes unaddressed in western, eastern and central sub-Saharan Africa, compared with less than 10% in high-income regions such as North America and western Europe.
Source: World Health Organization, 2026Instead of one “percent solved” score, DO GOOD rates three separate dimensions. A problem can have mature solutions that still reach too few people. These ratings are an editorial reading of the sources on this page, not a measured index.
Has the situation improved in the real world?
ModerateThe age-standardised prevalence of blindness among adults aged 50 and over fell 28.5% between 1990 and 2020, but because populations grew and aged, the number of people of all ages who are blind rose by 50.6% and of those with moderate or severe impairment by 91.7%.
How mature and validated are the available solutions?
HighGlasses for refractive error and cataract surgery are among the most cost-effective health interventions known, and vision rehabilitation improves functioning for people whose loss cannot be reversed.
How widely are effective solutions actually used?
ModerateAbout half of older adults who need cataract surgery have had it with a good result (48.2% in 2025), but in the WHO African Region fewer than one in four have, and in sub-Saharan Africa fewer than three in ten older adults who need distance correction have it with a good result (2023).
Estimates rest on hundreds of population surveys, but they are modelled: only 17% of the surveys used for refractive error coverage were nationally representative, many regions have little data, and there is almost no survey data from high-income countries.
Coverage of glasses and cataract surgery is rising, by about 5 percentage points a decade for refractive error since 2000, but far too slowly for the 2030 targets, while population ageing keeps increasing the number of people who need care.
Modelled estimates for 2020 put 43.3 million people as blind and 295 million with moderate or severe distance vision impairment. A further 258 million had mild distance impairment, and 510 million could not see clearly up close because they lacked reading glasses. WHO counts at least 1 billion people whose vision impairment could have been prevented or has not yet been addressed, with cataract (94 million) and uncorrected refractive error (88.4 million) the two largest causes of distance impairment. The Lancet Global Health Commission on Global Eye Health concluded that more than 90% of people with vision impairment have a preventable or treatable cause. The consequences reach far beyond sight: adults with vision impairment have lower rates of employment and higher rates of depression and anxiety, older people fall more often and enter care homes earlier, and WHO puts the annual global productivity loss at about US$411 billion (purchasing power parity).
About 90% of people affected live in low- and middle-income countries, where distance vision impairment is four times as common as in high-income regions. Among adults aged 50 and over, blindness is most common in western and eastern sub-Saharan Africa, South-East Asia and South Asia. Women make up about 55% of people who are blind, and the Commission found that women, rural populations and ethnic minority groups are more likely to have vision impairment. Children with vision impairment in several low- and middle-income countries are up to five times less likely to be in formal education. Because populations are growing and ageing, the number of people affected keeps rising even though the age-standardised rate of blindness among adults aged 50 and over fell by 28.5% between 1990 and 2020: the Commission expects 1.8 billion people to have vision impairment by 2050.
Global estimates come from the Vision Loss Expert Group, which models population-based eye surveys into figures for every country. Progress on services is tracked with two 'effective coverage' measures endorsed by the World Health Assembly. The main measures are:
Distance vision impairment and blindness
Based on the vision a person has with the glasses they already use (presenting visual acuity). Blindness means seeing less than 3/60, that is, needing to stand 3 metres from what a person with normal sight sees from 60 metres. Moderate and severe impairment covers vision worse than 6/18 down to 3/60, and mild impairment worse than 6/12 but at least 6/18.
Near vision impairment
Counted when a person whose distance vision is good (6/12 or better) cannot read small print at 40 cm, almost always because of age-related presbyopia that has not been corrected with reading glasses.
Effective cataract surgical coverage (eCSC)
Among adults aged 50 and over who have had or still need cataract surgery, the share who have been operated on and now see well enough (6/18 or better in the study used here; WHO's preferred threshold is 6/12). It captures both access and the quality of the result.
Effective refractive error coverage (eREC)
Among adults aged 50 and over who need distance glasses or other correction, the share who have it and see well (6/12 or better) with it. Most data come from Rapid Assessment of Avoidable Blindness surveys, which are often subnational, and near-vision coverage cannot yet be estimated reliably.
What works
A short, inexpensive operation replaces the clouded lens and usually restores sight. WHO lists it among the most cost-effective health interventions, and global effective coverage among adults aged 50 and over rose from 28.2% in 2000 to an estimated 48.2% in 2025.
Limits
Not every operation gives good vision: in Burundi only 2.1% of those in need had a good result although 10.2% had been operated. Residual refractive error caused 26.4% of poor outcomes, which better pre-operative measurement and glasses after surgery could largely fix.
What works
Correcting refractive error with glasses is simple and cheap. In a trial in India, free reading glasses raised the productivity of tea pickers with presbyopia by 22%, and in China glasses for schoolchildren cut the odds of failing a class by 44%.
Limits
Glasses only help if they are available, affordable, well made and actually worn, and in many low-income settings eye tests and dispensing are hard to reach.
What works
WHO's model of integrated, people-centred eye care, backed by a World Health Assembly resolution in 2020, brings vision screening, simple treatment and referral into primary care and health insurance packages, so that eye care is not left to separate, donor-funded programmes.
Limits
It depends on trained staff, referral routes to surgeons and financing that many health systems lack, and its effect on coverage takes years to show in surveys.
What works
Public health programmes combining antibiotics, surgery, hygiene and community-wide drug treatment have greatly reduced the prevalence of trachoma and onchocerciasis, two infectious causes of blindness, since the 1990s.
Limits
These programmes need sustained funding and access to remote and insecure areas to finish the job, and they address only a small share of global vision loss, which is mostly driven by cataract and refractive error.
What works
For people whose vision cannot be restored, for example after glaucoma or macular degeneration, low-vision aids, mobility training and assistive technology help them keep working, studying and living independently.
Limits
It does not prevent or reverse vision loss, and services, trained staff and affordable devices are hard to find in many settings.
Promising, but not proven at scale. The stage shows how far each approach has come; it is not a recommendation.
Algorithms that grade photographs of the retina can flag diabetic retinopathy and other conditions without a specialist present. The Commission sees large potential for such technology, but it still needs evaluation in routine low-resource services and a reliable path to treatment for those flagged.
Simple phone-based acuity tests and remote review by eye specialists let teachers and community health workers screen schools and villages. Screening only helps if referrals lead to glasses or surgery, and linking the two at scale is still being worked out.
Short-sightedness is increasing worldwide, and less time outdoors is one of the factors linked to it. Schools and clinics are testing more outdoor time and treatments that slow its progression, but how well these work across different populations and over many years is still uncertain.
WHO's SPECS 2030 initiative supports countries in reaching the more than 800 million people who need refractive error services, bringing governments, professional groups, industry and civil society behind the 2030 refractive error target. It is too early to know whether it will speed up coverage.
Implementation gap
In Kenya about 702 cataract operations are done per million people each year; reaching the 2030 target would need more than 7,000. At the current pace, a 2026 study expects four people to die untreated for every operation performed between 2025 and 2029.
Implementation gap
Two out of three people in low-income countries who need glasses do not have them, and one in two people worldwide who need cataract surgery have no access to it.
Implementation gap
The Commission found that the eye health workforce cannot meet population needs in many countries and recommended training more staff and sharing tasks among different cadres of health workers.
Technology gap
Coverage figures count only operations that leave people seeing well. Other eye diseases, residual refractive error and surgical complications each cause roughly a fifth to a quarter of poor outcomes. In Burundi, 10.2% of those in need had been operated on but only 2.1% had a good result.
Coordination gap
WHO calls for eye care to be built into national health systems and primary care rather than run as a separate service. Closing the gap in unmet need would cost about US$25 billion, much less than the estimated US$411 billion a year lost in productivity.
Knowledge gap
Only 42 of 237 surveys used to estimate refractive error coverage were nationally representative, most cover only adults aged 50 and over, and there is almost no survey data from high-income countries or on near vision.
Unresolved questions, not vetted breakthroughs. Answering any of them would change what is possible.
How can countries measure effective coverage for near vision and for younger adults and children, when current surveys mostly test distance vision in people aged 50 and over?
Why do women have lower coverage of cataract surgery and glasses in most regions, and which changes in cost, distance, information or service design close the gap?
Vision impairment is linked to cognitive decline and higher mortality. Does restoring sight with cataract surgery or glasses actually reduce these risks, and by how much?
How can countries with a few hundred cataract operations per million people raise output many times over while keeping outcomes good, and what mix of surgeons, mid-level staff and outreach works best?
Get an eye test if your sight changes, if you struggle to read up close, or regularly if you have diabetes or a family history of glaucoma, since some causes of vision loss give no early warning.
Make sure children have their vision tested, that they wear the glasses they are given, and that they spend time playing outdoors.
Give to organisations that fund cataract surgery, glasses or eye care training in low- and middle-income countries, ideally ones that report the visual results of their work, not only the number of operations.
Support efforts to include eye tests, glasses and cataract surgery in public health insurance and primary care, for example by raising it with elected representatives.
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World Health Organization (updated 10 February 2026), published 2026
WHO's current fact sheet. Source of the at least 1 billion people with preventable or unaddressed vision impairment, cause counts (cataract 94 million, refractive error 88.4 million, diabetic retinopathy 3.9 million), regional contrasts, access gaps for glasses and cataract surgery, the US$411 billion productivity loss and US$25 billion cost gap, and SPECS 2030.
GBD 2019 Blindness and Vision Impairment Collaborators and Vision Loss Expert Group, The Lancet Global Health 9(2):e130–e143, published 2021
The reference global estimates (used by WHO and the IAPB Vision Atlas), modelled from 528 data sources. Source of the 2020 counts by severity, the share of women, definitions, regional prevalence and the 1990–2020 changes. No newer full global update has been published.
Burton M.J. et al., The Lancet Global Health 9(4):e489–e551, published 2021
Commission report on the state of eye health and how to improve it. Source of the 1.1 billion figure for 2020 and 1.8 billion projection for 2050, the over 90% preventable or treatable share, effects of glasses on productivity and schooling, education gaps for children, workforce shortages and the link to universal health coverage.
McCormick I. et al. (eCSC Study Group), The Lancet Global Health 14:e367–e377 (online 10 February 2026), published 2026
Latest global and regional estimates of cataract surgery coverage, from 233 surveys with 779,706 participants. Source of the trend from 2000 to 2030, regional and sex differences, causes of poor outcomes, the projected 8.4-point rise and data limitations.
Bourne R.R.A. et al. (Vision Loss Expert Group and RAAB International), The Lancet Global Health 13(8):e1396–e1405, published 2025
Latest estimates of coverage of glasses and other distance correction among adults aged 50 and over, from 237 surveys. Source of the global and regional 2023 values, trend since 2000, sex gap, the 40-point target and the finding that no large country is on track.
International Centre for Eye Health, London School of Hygiene & Tropical Medicine (11 February 2026), published 2026
Research summary from the authors' institution covering the 2026 eCSC study and a companion study of cataract backlog in Kenya (Lancet Healthy Longevity, 2026). Source of the Kenya surgical rates and the estimate of deaths before surgery.
DO GOOD International (2026). Ending Avoidable Blindness. Global Challenges. Updated October 15, 2026. https://www.dogood.world/challenges/vision-loss
For figures, please cite the original sources listed above.