The Peter Watson Memorial Lecture "Vision for the World".

In the 1990s attention was drawn to the huge global problem of blindness and vision loss; most of which was unnecessary, being preventable or treatable. This led to the global initiative, Vision 2020. Over the last 30 years a lot of progress has been made in developing and implementing eye care programmes to address this and particularly to reach underserved populations. In 2019 the World Health Organisation produced the World Report on Vision that sets a clear pathway to develop Integrated Person-centred Eye Care. Indicators have been developed to track progress and national governments are to report on their progress. Data on eye health and vision loss have been collected from multiple population-based studies and analysed by the Vision Loss Expert Group. These data show that although the prevalence rates of vision loss and blindness are decreasing around the world, the actual number of people affected is slowly increasing. This is due to both population growth and the aging of the population. To provide the equity in eye care that is required, attention needs to be paid to integrating eye care into primary care and linking it with other specialist services. An important step is the training and development of coordinated eye care teams that are resourced to meet their population-based needs and to monitor the progress being made.

Effective refractive error coverage in adults aged 50 years and older: estimates from population-based surveys in 61 countries.

BACKGROUND: In 2021, WHO Member States endorsed a global target of a 40-percentage-point increase in effective refractive error coverage (eREC; with a 6/12 visual acuity threshold) by 2030. This study models global and regional estimates of eREC as a baseline for the WHO initiative. METHODS: The Vision Loss Expert Group analysed data from 565 448 participants of 169 population-based eye surveys conducted since 2000 to calculate eREC (met need/[met need + undermet need + unmet need]). A binary logistic regression model was used to estimate eREC by Global Burden of Disease (GBD) Study super region among adults aged 50 years and older. FINDINGS: In 2021, distance eREC was 79·1% (95% CI 72·4-85·0) in the high-income super region; 62·1% (54·7-68·8) in north Africa and Middle East; 49·5% (45·0-54·0) in central Europe, eastern Europe, and central Asia; 40·0% (31·7-48·2) in southeast Asia, east Asia, and Oceania; 34·5% (29·4-40·0) in Latin America and the Caribbean; 9·0% (6·5-12·0) in south Asia; and 5·7% (3·1-9·0) in sub-Saharan Africa. eREC was higher in men and reduced with increasing age. Global distance eREC increased from 2000 to 2021 by 19·0%. Global near vision eREC for 2021 was 20·5% (95% CI 17·8-24·4). INTERPRETATION: Over the past 20 years, distance eREC has increased in each super region yet the WHO target will require substantial improvements in quantity and quality of refractive services in particular for near vision impairment. FUNDING: WHO, Sightsavers, The Fred Hollows Foundation, Fondation Thea, Brien Holden Vision Institute, Lions Clubs International Foundation.

The true cost of hidden waiting times for cataract surgery in Australia.

Cataract surgery is a safe, effective and common elective procedure in Australia but access is inequitable. True waiting times for cataract care are undisclosed or inconsistently reported by governments. Estimates of true waiting times range from 4 to 30 months and have been extended during the coronavirus disease 2019 (COVID-19) pandemic. Comparative analysis revealed that reducing waiting periods from 12 to 3 months would result in estimated public health system cost savings of $6.6 million by preventing 50 679 falls. Investment in public cataract services to address current unmet needs would prevent avoidable vision impairment and associated negative consequences.

Trachoma.

Trachoma is a neglected tropical disease caused by infection with conjunctival strains of Chlamydia trachomatis. It can result in blindness. Pathophysiologically, trachoma is a disease complex composed of two linked chronic processes: a recurrent, generally subclinical infectious-inflammatory disease that mostly affects children, and a non-communicable, cicatricial and, owing to trichiasis, eventually blinding disease that supervenes in some individuals later in life. At least 150 infection episodes over an individual's lifetime are needed to precipitate trichiasis; thus, opportunity exists for a just global health system to intervene to prevent trachomatous blindness. Trachoma is found at highest prevalence in the poorest communities of low-income countries, particularly in sub-Saharan Africa; in June 2021, 1.8 million people worldwide were going blind from the disease. Blindness attributable to trachoma can appear in communities many years after conjunctival C. trachomatis transmission has waned or ceased; therefore, the two linked disease processes require distinct clinical and public health responses. Surgery is offered to individuals with trichiasis and antibiotic mass drug administration and interventions to stimulate facial cleanliness and environmental improvement are designed to reduce infection prevalence and transmission. Together, these interventions comprise the SAFE strategy, which is achieving considerable success. Although much work remains, a continuing public health problem from trachoma in the year 2030 will be difficult for the world to excuse.

Change in the prevalence of myopia in Australian middle-aged adults across 20 years.

BACKGROUND: The prevalence of myopia is increasing globally including in Europe and parts of Asia but Australian data are lacking. This study aim described the change in myopia prevalence in middle-aged Australian adults over approximately a 20-year period. METHODS: Two contemporary Western Australian studies (conducted in mid-late 2010s): the coastal-regional Busselton Healthy Ageing Study (BHAS) and the urban Gen1 of the Raine Study (G1RS) were compared to two earlier studies (early-mid 1990s) in Australia: the urban Blue Mountains Eye Study (BMES) and urban/regional Melbourne Visual Impairment Project (MVIP). Refractive error was measured by autorefraction, vertometry, or subjective refraction. Participants (49-70 years) of European descent without self-reported/diagnosed cataract, corneal disease, or refractive or corneal surgery were included. RESULTS: After exclusions, data were available from 2217, 1760, 700, 2987 and 756 participants from BMES, urban MVIP, regional MVIP, BHAS, and G1RS, respectively. The mean age ranged from 57.1 ± 4.6 years in the G1RS to 60.1 ± 6.0 years in the BMES; 44-48% of participants were male. When stratified by location, the contemporary urban G1RS cohort had a higher age-standardised myopia prevalence than the urban MVIP and BMES cohorts (29.2%, 16.4%, and 23.9%, p < 0.001). The contemporary coastal-regional BHAS had a higher age-standardised myopia prevalence than the regional MVIP cohort (19.4% vs. 13.8%, p = 0.001). CONCLUSIONS: We report an increase in myopia prevalence in older adults in Australia born after World War ll compared to cohorts born before, accounting for urban/regional location. The prevalence of myopia remains relatively low in middle-aged Australian adults.

Conjunctival Scarring, Corneal Pannus, and Herbert's Pits in Adolescent Children in Trachoma-endemic Populations of the Solomon Islands and Vanuatu.

BACKGROUND: In the Solomon Islands and Vanuatu, the sign trachomatous inflammation-follicular (TF) is common, but ocular infection with Chlamydia trachomatis is not. It is therefore debatable whether azithromycin mass drug administration (MDA), the recommended antibiotic treatment strategy for trachoma's elimination as a public health problem, is necessary in this setting. We set out to estimate what proportion of adolescents were at risk of progression of trachomatous scarring. METHODS: A cross-sectional survey was undertaken of all children aged 10-14 years resident in communities identified as high-TF clusters during previous population-based mapping. Graders examined children for clinical evidence of trachomatous scarring, pannus, and Herbert's pits (HPs) or limbal follicles in both eyes. A dried blood spot was collected from each child and tested for antibodies to C. trachomatis. RESULTS: A total of 492 children in 24 villages of the Solomon Islands and Vanuatu were examined. In total, 35/492 (7%) of children had limbal signs (pannus and/or HPs) plus any conjunctival scarring. And 9/492 (2%) had limbal signs and moderate or severe conjunctival scarring; 22% of children were anti-Pgp3 seropositive. CONCLUSIONS: Few adolescents here are at risk of future complications from trachoma, supporting the conclusion that further antibiotic MDA is not currently required for trachoma elimination purposes in these settings.

The simplified trachoma grading system, amended.

A simplified grading system for trachoma was published by the World Health Organization (WHO) in 1987. Intended for use by non-specialist personnel working at community level, the system includes five signs, each of which can be present or absent in any eye: (i) trachomatous trichiasis; (ii) corneal opacity; (iii) trachomatous inflammation-follicular; (iv) trachomatous inflammation-intense; and (v) trachomatous scarring. Though neither perfectly sensitive nor perfectly specific for trachoma, these signs have been essential tools for identifying populations that need interventions to eliminate trachoma as a public health problem. In 2018, at WHO's 4th global scientific meeting on trachoma, the definition of one of the signs, trachomatous trichiasis, was amended to exclude trichiasis that affects only the lower eyelid. This paper presents the amended system, updates its presentation, offers notes on its use and identifies areas of ongoing debate.

En 1987, l'Organisation mondiale de la Santé a publié un système de codage simplifié du trachome. Destiné au personnel non qualifié travaillant au sein des communautés, il comporte cinq signes, chacun pouvant être présent ou absent dans l'un ou l'autre œil: (i) le trichiasis trachomateux; (ii) l'opacité cornéenne; (iii) l'inflammation trachomateuse ­ folliculaire; (iv) l'inflammation trachomateuse ­ intense; et enfin, (v) la cicatrice trachomateuse. Bien qu'ils ne soient ni parfaitement précis, ni totalement spécifiques au trachome, ces signes constituent des outils essentiels pour identifier les populations qui nécessitent une intervention afin d'éliminer le trachome en tant que problème de santé publique. En 2018, lors de la quatrième réunion scientifique mondiale sur le trachome, la définition de l'un des signes, le trichiasis trachomateux, a été modifiée pour exclure du système de codage le trichiasis qui n'affecte que la paupière inférieure. Ce document expose le nouveau système, actualise sa présentation, formule des remarques sur son utilisation et identifie les domaines qui font encore l'objet de débats.

En 1987, la Organización Mundial de la Salud (OMS) publicó un sistema de clasificación simplificado para el tracoma. Este sistema fue diseñado para que lo utilice el personal no especializado que trabaja a nivel comunitario e incluye cinco signos, cada uno de los cuales puede estar presente o ausente en los ojos: i) la triquiasis tracomatosa; ii) la opacidad corneal; iii) la inflamación tracomatosa-folicular; iv) la inflamación tracomatosa-intensa; y v) la cicatrización tracomatosa. Si bien no son perfectamente sensibles ni muy específicos del tracoma, estos signos han sido herramientas esenciales para identificar a las poblaciones que requieren intervenciones para eliminar el tracoma como problema de salud pública. En 2018, se modificó la definición de uno de los signos, la triquiasis tracomatosa, en la 4.ª Reunión Científica Mundial sobre el Tracoma de la OMS, para descartar la triquiasis que solo afecta al párpado inferior. En el presente documento se describe el sistema modificado, se actualiza su presentación, se ofrecen observaciones sobre su aplicación y se identifican los ámbitos de debate en curso.

Prevalence and associations of non-retinopathy ocular conditions among older Australians with self-reported diabetes: The National Eye Health Survey.

AIM: To determine the prevalence and associations of non-retinopathy ocular conditions among older Australian adults with diabetes. METHODS: Multistage random-cluster sampling was used to select 3098 non-indigenous Australians aged 50y or older (46.4% male) and 1738 indigenous Australians aged 40y or older (41.1% male) from all levels of geographic remoteness in Australia. Participants underwent a standardised questionnaire to ascertain diabetes history, and a clinical examination to identify eye disease. We determined the prevalence of uncorrected refractive error, visually significant cataract, cataract surgery, age-related macular degeneration, glaucoma, ocular hypertension, retinal vein occlusion and epiretinal membrane among those with and without self-reported diabetes. RESULTS: Participants with self-reported diabetes had a higher prevalence of cataract surgery than those without diabetes (28.8% vs 16.9%, OR 1.78, 95%CI: 1.35-2.34 among non-indigenous Australians, and 11.3% vs 5.2%, OR 1.62, 95%CI: 1.22-2.14 among indigenous Australians). Diabetic retinopathy (DR) increased the odds of cataract surgery among self-reported diabetic indigenous and non-indigenous Australians (OR 1.89, P=0.004 and OR 2.33, P<0.001 respectively). Having diabetes for ≥20y and having vision-threatening DR increased the odds of cataract surgery among indigenous Australians with diabetes (OR 3.73, P=0.001 and 7.58, P<0.001, respectively). CONCLUSION: Most non-retinopathy ocular conditions are not associated with self-reported diabetes. However, to account for Australia's worsening diabetes epidemic, interventions to reduce the impact of diabetes-related blindness should include increased cataract surgery services.

Future burden of vision loss in Australia: Projections from the National Eye Health Survey.

IMPORTANCE: Projections of Australia's future burden of vision loss will inform eye health service delivery. BACKGROUND: This study aimed to forecast bilateral vision loss in Australia from 2020 to 2050. DESIGN: Population-based survey. PARTICIPANTS: Indigenous and non-indigenous Australians (n = 4253) aged ≥50 years from the National Eye Health Survey (NEHS, 2015-2016). METHODS: Using the age-and-sex-stratified prevalence of vision loss (better eye visual acuity <6/12) from the NEHS, the prevalence of, and number of people aged ≥50 years with, vision loss were forecast to 2050 using Australian census projections. MAIN OUTCOME MEASURE: Prevalence of, and number of Australians with, vision loss from 2020 to 2050. RESULTS: The prevalence of vision loss is predicted to increase from 6.7% to 7.5% by 2050. Owing to population dynamics, the estimated number of Australians ≥50 years old with vision loss will nearly double from 532 386 in 2016 to 1 015 021 in 2050. The greatest increase in vision loss is expected to occur in those aged ≥80 years (2.6-fold, 2016 = 144 240; 2050 = 376 296). The number of people with uncorrected refractive error is projected to increase 1.7-fold, from 331 914 in 2016 to 578 969 in 2050. CONCLUSIONS AND RELEVANCE: Due to population growth and ageing, the future burden of vision loss in Australia is likely to increase, but the magnitude of this change is uncertain due to a lack of available data on some relevant input variables. Nonetheless, efforts are required to ensure early detection and treatment of major eye conditions, particularly treatable conditions such as uncorrected refractive error and cataract.

Prevalence and causes of vision loss in sub-Saharan Africa in 2015: magnitude, temporal trends and projections.

BACKGROUND: This study aimed to assess the prevalence and causes of vision loss in sub-Saharan Africa (SSA) in 2015, compared with prior years, and to estimate expected values for 2020. METHODS: A systematic review and meta-analysis assessed the prevalence of blindness (presenting distance visual acuity <3/60 in the better eye), moderate and severe vision impairment (MSVI; presenting distance visual acuity <6/18 but ≥3/60) and mild vision impairment (MVI; presenting distance visual acuity <6/12 and ≥6/18), and also near vision impairment (

Cataract surgery and Indigenous eye care: A review.

Cataract remains the leading cause of blindness in Aboriginal and Torres Strait Islander peoples and is still a major cause of vision loss. The pathway of care to cataract surgery has many potential gaps and barriers. Although there has been a significant increase in services over the last few years, there is still the urgent need to facilitate timely and affordable cataract surgery. Particularly for public surgery there needs to be a significant decrease in waiting times for the clinical assessment of those needing surgery and for those on a surgical waiting list.

Estimated number of ophthalmologists worldwide (International Council of Ophthalmology update): will we meet the needs?

BACKGROUND/AIMS: To estimate 2015 global ophthalmologist data and analyse their relationship to income groups, prevalence rates of blindness and visual impairment and gross domestic product (GDP) per capita. METHODS: Online surveys were emailed to presidents/chairpersons of national societies of ophthalmology and Ministry of Health representatives from all 194 countries to capture the number and density (per million population) of ophthalmologists, the number/density performing cataract surgery and refraction, and annual ophthalmologist population growth trends. Correlations between these data and income group, GDP per capita and prevalence rates of blindness and visual impairment were analysed. RESULTS: In 2015, there were an estimated 232 866 ophthalmologists in 194 countries. Income was positively associated with ophthalmologist density (a mean 3.7 per million population in low-income countries vs a mean 76.2 in high-income countries). Most countries reported positive growth (94/156; 60.3%). There was a weak, inverse correlation between the prevalence of blindness and the ophthalmologist density. There were weak, positive correlations between the density of ophthalmologists performing cataract surgery and GDP per capita and the prevalence of blindness, as well as between GDP per capita and the density of ophthalmologists doing refractions. CONCLUSIONS: Although the estimated global ophthalmologist workforce appears to be growing, the appropriate distribution of the eye care workforce and the development of comprehensive eye care delivery systems are needed to ensure that eye care needs are universally met.

Prevalence and causes of vision loss in East Asia in 2015: magnitude, temporal trends and projections.

BACKGROUND: To determine the prevalence and causes of blindness and vision impairment (VI) in East Asia in 2015 and to forecast the trend to 2020. METHODS: Through a systematic literature review and meta-analysis, we estimated prevalence of blindness (presenting visual acuity <3/60 in the better eye), moderate-to-severe vision impairment (MSVI; 3/60≤presenting visual acuity <6/18), mild vision impairment (mild VI: 6/18≤presenting visual acuity <6/12) and uncorrected presbyopia for 1990, 2010, 2015 and 2020. A total of 44 population-based studies were included. RESULTS: In 2015, age-standardised prevalence of blindness, MSVI, mild VI and uncorrected presbyopia was 0.37% (80% uncertainty interval (UI) 0.12%-0.68%), 3.06% (80% UI 1.35%-5.16%) and 2.65% (80% UI 0.92%-4.91%), 32.91% (80% UI 18.72%-48.47%), respectively, in East Asia. Cataract was the leading cause of blindness (43.6%), followed by uncorrected refractive error (12.9%), glaucoma, age-related macular degeneration, corneal diseases, trachoma and diabetic retinopathy (DR). The leading cause for MSVI was uncorrected refractive error, followed by cataract, age-related macular degeneration, glaucoma, corneal disease, trachoma and DR. The burden of VI due to uncorrected refractive error, cataracts, glaucoma and DR has continued to rise over the decades reported. CONCLUSIONS: Addressing the public healthcare barriers for cataract and uncorrected refractive error can help eliminate almost 57% of all blindness cases in this region. Therefore, public healthcare efforts should be focused on effective screening and effective patient education, with access to high-quality healthcare.

Prevalence, associations and characteristics of severe uncorrected refractive error in the Australian National Eye Health Survey.

IMPORTANCE: In Australia, nationally representative data of the burden and associations of severe uncorrected refractive error are scarce. BACKGROUND: To report the prevalence and characteristics of severe uncorrected refractive error in Indigenous and non-Indigenous Australians. DESIGN: Population-based cross-sectional study. PARTICIPANTS: A total of 3098 non-Indigenous Australians aged 50 to 98 and 1738 Indigenous Australians aged 40 to 92 living in 30 randomly selected Australian sites were examined. METHODS: Severe uncorrected refractive error was defined as an improvement of ≥2 lines on the logMAR chart in one or both eyes in participants with a presenting visual acuity <6/12. MAIN OUTCOME MEASURE: Severe uncorrected refractive error RESULTS: Prevalence of severe uncorrected refractive error was 11.0% (95% confidence interval 9.3-13.0) in non-Indigenous and 14.5% (12.5-16.7) in Indigenous Australians. Eighty-two percent of non-Indigenous and 77% of Indigenous participants had a spherical equivalent refraction between -2.00D and +2.00D. Indigenous Australians who were older (odds ratio [OR] for 70-79 years vs 40-49 years = 3.59), resided in outer regional areas (OR = 1.78) and did not have an eye examination in the previous 2-years (OR = 1.50) were associated with higher odds of severe uncorrected refractive error. Geographical remoteness (OR = .68 for inner regional), male gender (OR = 1.30), older age (OR for 70-79 years vs 50-59 years = 1.51) and failure to have an eye examination in the previous 2-years (OR = 2.06) were associated with severe uncorrected refractive error among non-Indigenous participants. CONCLUSIONS AND RELEVANCE: Increased public awareness of the importance of regular optometric examinations may be required in groups at high risk of severe uncorrected refractive error.