Global rates of avoidable blindness are set to increase threefold in the next four decades, warns a report by the International Agency for the Prevention of Blindness (IAPB).

Countries in sub-Saharan Africa and South Asia are feared to be most at risk.

The research points to 30 years of stagnation in tackling the leading cause of avoidable blindness, especially among people aged over 50.

The IAPB, an international alliance of eye care organisations, believes this stagnation is partly due to a rise in the world's ageing population.

Cataracts, glaucoma and untreated cases of blurred vision are some of the leading causes of blindness, according to the report published in the Lancet medical journal.

A lack of resources is blamed for sub-Saharan Africa's failure to match the progress seen in higher income countries, the report says, highlighting the need for a massive increase in eye care provision.

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