Worldwide, at least 2.2 billion people have near or distance vision impairment, which can lead to permanent blindness. For over a billion of them, this impairment is caused by an eye condition that could be treated or prevented through basic care such as wearing glasses or cataract surgery. Without sufficient investment, this number could rise to 1.8 billion by 2050.
Globally, the leading causes of visual impairment and blindness are:
- refractive errors
- cataracts
- diabetic retinopathy
- glaucoma
- age-related macular degeneration
Some of these conditions, like trachoma and cataracts, must be diagnosed and treated quickly to prevent vision loss.
Uncorrected refractive errors
Refractive errors are abnormalities caused by irregularities in the shape of the eye, making it difficult to focus images. This results in blurred and impaired vision. Refractive errors include myopia, hyperopia, astigmatism, and presbyopia.
161 million people live with uncorrected refractive errors, which represent the most common cause of visual impairment. Globally, only an estimated 36% of people with distance vision impairment due to refractive error have access to glasses (source: WHO).
Without proper correction, refractive errors can lead to blindness, of which they represent the second leading cause worldwide.
Eye diseases
Eye diseases differ from refractive errors. They’re numerous, and while some have symptoms (discomfort, pain, decreased visual acuity, visual field deficits, or double vision), others only show symptoms late in their progression—which is why regular eye exams are essential.
There are also variations in the causes of visual impairment between and within countries, depending on the availability and affordability of eye care services. For example, the proportion of visual impairment due to unoperated cataracts is higher in low- and middle-income countries.
Access to eye care: a challenge for rural populations
Eye disorders pose a particularly serious problem in these countries, where many people can’t afford an eye exam or glasses to improve their vision. Access to eye care is also a challenge for rural populations. In the regions where OPC works, most ophthalmologists and optometrists practice in cities, creating a shortage of trained professionals in rural areas.
Reducing and correcting refractive errors is essential for providing sustainable, comprehensive eye care. In collaboration with its partners and donors, OPC ensures that uncorrected refractive errors are addressed as part of its comprehensive eye care programs across francophone Africa.