Eyes-Road - Another vision of EDI > All Blog > Actualités Optiques > DOSSIER – Santé Visuelle Mondiale, où en est-on ?

DOSSIER - Global Visual Health, where are we?

Reading time : 5 minutes


Like all health problems, blindness and visual impairment are among the concerns of the World Health Organization (WHO) . Regularly, the specialized agency of the United Nations (UN) presents the figures of global vision health , as well as short and medium-term strategic plans.

As health professionals visual , industrialists and opticians alike have a duty to inform themselves of what is being implemented at the global level. This file is therefore the means to take stock of the figures in the world and in France. But also on the causes of eye diseases and the plans that can be developed to combat them.

Global Visual Health: Everyone's Business

There are several hundred eye diseases . While some are qualified as benign and do not cause any visual impairment, they can cause bothersome symptoms. Others can unfortunately lead to complete and irreversible blindness .

WHO highlights several characteristics of eye diseases , which should be associated with a global social context. Indeed, while on the planet, all age groups (from infants to the elderly) and all social classes are concerned. Women are affected as much as men.


However, the organization believes that poverty has an impact on the causes as well as the consequences of visual impairment . Indeed, access to health care is difficult in some parts of the world, and people with disabilities are, according to a report, more vulnerable to abuse and violence. As a bonus, their stigma and discrimination prevent them from participating in and contributing to family and community life on an equal basis.

WHO insists therefore on the need not to be concerned only with the treatment of eye diseases, but to organize prevention through the planning of eye care responding to needs across the globe.

By elsewhere, the phenomenon of global vision health is also, as the organization suggests, "just the tip of the iceberg of vision problems." According to her, a large number of people experience vision problems “without having reached a well-defined threshold of visual impairment.”

There are diseases that do not always lead to difficulties while others cause them without having crossed at a given moment the threshold of visual impairment.

Disturbing figures

First, how to define visual impairment?

The Eleventh International Classification of Diseases (ICD-11, 2018) distinguishes two distinct groups of visual impairments. Those affecting distance vision, as corrected, and those affecting near vision, as corrected.

Impairments affecting distance vision:

  • mild – corrected visual acuity less than 6/12;
  • moderate – corrected visual acuity less than 6/18;
  • severe – corrected visual acuity less than 6/60;
  • blindness – corrected visual acuity less than 3/60.

Impairments affecting near vision:

  • visual acuity less than N6 or N8 at 40 cm with the existing correction.

To this we must add different factors because the individual experience of visual impairment can differ from one person to another. Indeed, the availability of care, preventive and treatment interventions or even access to visual rehabilitation (this concerns optical devices but also, for example, canes for the visually impaired), information or transport, are all imponderables which will have consequences, sometimes heavy, on the results.


Globally, in 2020, it is estimated that approximately 1.3 billion people are living with some form of near or far vision impairment.

In far vision, 188.5 million people have mild visual impairment and 217 million have moderate to severe visual impairment, while 36 million people are blind. In addition, 826 million people live with an impairment affecting near vision.

These figures relate to both developed and developing countries. Population growth as well as the aging of the population tend to increase the risk of having more and more people with visual impairment.

Multiple causes

There are many causes of visual impairment. The main ones being:

  • uncorrected refractive errors
  • cataract
  • age-related macular degeneration
  • glaucoma
  • diabetic retinopathy
  • corneal clouding
  • trachoma

WHO also estimates that the main causes of blindness are:

  • unoperated cataract: 35%
  • uncorrected refractive errors: 21%
  • glaucoma: 8%

It is clear that the vast majority of these afflictions are due to poor treatment and uncorrected faults. This confirms the will to fight of international actors.


From one country to another, they may vary. For example, the proportion of visual impairment attributable to cataracts is higher in low- and middle-income countries than in higher-income countries.

In countries So-called "developed" diseases such as diabetic retinopathy , glaucoma and age-related macular degeneration are, on the contrary, more common.

Prevention from an early age

As seen previously, there is no age for developing a visual impairment . The work with them in terms of global vision health is considerable, but essential.

The causes of visual impairment in children vary from country to country. In developing countries, congenital cataract is one of the main causes, while in higher income countries retinopathy of prematurity is more common.

C t is especially the over-development of myopia over the years that worries. In Asia, it is increasingly mentioned as an epidemic. Here again, the lack of control from an early age tends to worsen the situation.

In France, 7 out of 10 parents think that vision control is only necessary. after 3 years. The child's first ophthalmological consultation, during a routine check-up, is in marked decline: 39% in 2019 compared to 55% in 2013

The digital lifestyle of the 21st century century has also passed through this. Ultraviolet rays and blue light from screens, viewed all day long, will considerably prevent any improvement.


What strategy to adopt?

To prevent the majority of visual impairments, nearly 80% preventable, you need to be able to perform interventions and raise awareness . A global plan has been put in place by the WHO. This plan, adopted in 2013 at the World Health Assembly , makes it possible to develop tools to evaluate the provision of services in all countries.

This plan notably targets the evaluation of eye health services but also of diabetes, to prevent diabetic retinopathy, and of vision rehabilitation for those whose deficiency could prove to be irreversible.

To l Currently, WHO is also in the process of producing a global vision report . The latter must offer recommendations to ensure comprehensive and integrated eye care in countries. The said report is also expected to help shape a global agenda of action for vision, while helping member states reduce the burden of eye disease, improving the lives of people with eye disabilities in order to achieve the Sustainable Development Goals. fixed.