Sight Savers International will issue the warning on Thursday October 12, which has been designated World Sight Day. Executive director Richard Porter said: 'This shocking figure is a reflection of the fact that 80 per cent of blindness is preventable or curable, yet right now there are 45 million people worldwide who have lost their sight because of cataracts, river blindness, vitamin A deficiency and trachoma.' Reverse Blindness - the charity's major international campaign - has already won the support of secretary general of the United Nations, Kofi Annan, secretary of state for development, Clare Short MP, and the prime minister's wife, Cherie Booth QC. Ms Booth commented: 'It is tragic when anybody loses their sight. However, when a person goes blind for no good reason, when their sight could be saved with the correct treatment, it is not just tragic, it is unacceptable. A child goes blind needlessly every minute, for want of a simple, cheap treatment and this must be stopped.' World Sight Day activities in the UK will focus around the British Airways London Eye, which will operate in reverse on October 12 to represent the title of the campaign.