"285 million people are estimated to be visually impaired worldwide: 39 million are blind and 246 million have low vision. About 90% of the world's visually impaired live in low-income settings." (WHO, 2014)
South East Asia is the region with the highest rate of preventable blindness, which constitutes 28% of the visually impaired globally.
Cataracts (47.9%) remains the leading cause of visual impairment in all areas of the world, except for developed countries. Other causes are Trachoma (3.6%), Onchocerciasis (0.8%), Diabetic retinopathy (4.8%) and childhood blindness (3.9%).
These are all avoidable visual impairment.
"About 65% of all people who are visually impaired are aged 50 and older. With an increasing elderly population in many countries, more people will be at risk of visual impairment due to chronic eye diseases and ageing processes."
top Causes of visual impairment
What is Cataract?
"It is a clouding of the lens in the eye." "This is due to aging but may also occur due to trauma or radiation exposure, be present from birth, or occur following eye surgery for other problems." (Wiki)
What is Trachoma?
"It is an infection, which causes a roughening of the inner surface of the eyelids that leads to pain. Untreated, repeated trachoma infections can result in a form of permanent blindness when the eyelids are internally scarred and then turn inward." (Wiki)
What is Onchocerciasis?
Onchocerciasis is also known as river blindness, which is an infection that could lead to blindness. It is spread by the bites of a black fly.
What is Diabetic retinopathy?
What is Childhood Blindness?
There are effective known strategies for the elimination of preventable blindness. Cataract, onchocerciasis, and trachoma are the principal diseases for which world strategies and programmes have been developed. World Health Organization (WHO) has a Global Initiative to Eliminate Avoidable Blindness, "VISION 2020: The Right to Sight".
Based on Sightsavers,
- A cataract operation takes about 20 minutes. It costs about £30 for an adult and £50 for a child (the higher cost is because an anaesthetist and an overnight stay are usually needed for children's operations).
- Trachoma can be prevented with a tablet that costs 35 pence. Surgery to treat trichiasis (advanced trachoma) costs about £8.
- Onchocersiasia (or river blindness) costs an unbelievable 7 pence per person to treat each year (a tablet is taken for 10-15 years until the risk is eliminated).
"Elimination of the Trachoma is possible through implementation of the SAFE strategy, a comprehensive approach that employs
- antibiotics (via Pfizer's donation of Zithromax),
- facial cleanliness and
- environmental improvement (clean water and sanitation management)
to address the underlying causes of the disease." (SCI)
River blindness (onchocerciasis), Cataract operations & Trachoma antibiotics
Also: Refractive error (eye glasses needed), Glaucoma (group of eye conditions)
- Cataract, Trachoma, Diabetic retinopathy & Childhood blindness
- (WHO, 2014)