WORLDWIDE PREVALENCE OF VISION IMPAIRMENT

There are an estimated 180 million persons worldwide who are visually 

impaired.  Of these, between 40 and 45 million persons are blind (World 

Health Organization, 2001). 

It is estimated that at least 7 million people in world become blind each 

year, with over 70% having vision restored with treatment.  Therefore, the 

number of blind people worldwide is increasing by up to 2 million per year 

(World Health Organization, 1997b). 

Among persons who are blind worldwide: 

58% are age 60+ 

32% are age 45 59 

7% are age 15 44  

4% are age 14 or under  

(Thylefors, et al., 1995). 

It is projected that by the year 2020, there will be about 54 million blind 

persons age 60+ worldwide (if no additional resources become available) 

(World Health Organization, 1997b). 

Causes of Vision Impairment & Blindness 

According to Prevent Blindness America (1994), cataract is the leading cause of 

blindness in the world. 

The following estimates are from the World Health Organization (1997c).  

It is estimated that, depending on the cause, up to 80% of blindness and serious 

vision loss could be avoided (prevented or treated). 

The major causes of avoidable vision loss are:  cataract, trachoma, and glaucoma. 

Together, they account for more than 70% of the word s blindness.  

Cataract accounts for an estimated 16 million cases of blindness worldwide; it 

accounts for approximately 1/2 of all cases in most countries of Africa and Asia. 

Trachoma, the 2

nd

 leading cause of blindness worldwide is the cause of 15% of all 

blindness worldwide.  There are an estimated 6 million persons with irreversible 

blindness due to trachoma and 146 million with active cases in need of treatment. 

Glaucoma is the 3

rd

 leading cause of blindness worldwide and is responsible for 

about 5.2 million cases of blindness.  Estimates of the number of persons 

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