Chronic diseases replace infections as leading causes of blindness, UN says

After an intensive drive against the communicable causes of blindness, chronic diseases, such as diabetes, and age-related illnesses have become the major reasons why nearly 40 million people worldwide cannot see, the United Nations health agency said today.

According to the latest data collected for the UN World Health Organization's (WHO) "Vision 2020: The Right to Sight" programme, 37 million people were blind, including 1.4 million youngsters under the age of 15, in 2002. Vision 2020 aims to eliminate avoidable blindness by 2020.

Aging brought on 75 per cent of blindness in 2002, WHO said. In 1992 the leading causes were two communicable diseases: trachoma and onchocerciasis, or "river blindness."

"Changes in the pattern of avoidable blindness can be attributed to significant achievements in the prevention and management of some causes of avoidable blindness," says WHO's Dr. Serge Resnikoff. "In addition, we now have much better data, which is giving us a more accurate estimate of causes."

Trachoma is spread by eye-seeking flies and by contact with discharges from infected eyes. It has been treated by a combination of methods called SAFE: surgery for inturned eyelashes, antibiotics, facial cleanliness and environmental improvement. Onchocerciasis, or "river blindness," is caused by the filaria nematode, along with Wolbachia bacteria, entering the body.

Two years ago cataracts caused 47.8 per cent of global blindness, especially in developing countries, but other age-related conditions were increasing in impact. Glaucoma caused 12.3 per cent of blindness, age-related macula degeneration, 8.7 per cent, and diabetic retinopathy, 4.8 per cent. Another 124 million people with low vision were at risk for blindness.

With the number of elderly people worldwide by 2020 estimated at 698 million, 67 per cent of them in developing countries, the public health agency said, the world now had to correct the distribution of resources and provide available existing and new drugs and other treatments for eye diseases worldwide.

WHO said integrating eye care into the primary health care system had contributed to the decline in vision loss from trachoma, onchocerciasis, vitamin A deficiency, and even cataracts, but public health planners needed to manage the diseases now becoming prevalent.