It is an epidemic that has crept up on Hong Kong in the past generation and which now affects an astonishing seven out of 10 people in the city - and office workers are in the front line when it comes to casualties. More people suffer from myopia or short-sightedness in Hong Kong than almost anywhere else in the world. In the United States, only one in four people suffer from the condition. Short-sightedness has become so widespread that anyone who manages to go through school and college without needing glasses or contact lenses is highly likely to need them early in their working life in Hong Kong. There are ways to prevent it or to slow down its progress, but experts say that genetic and environmental factors are heavily loaded against Hong Kong people when it comes to preserving 20/20 vision. Research has found that Chinese people are more prone to short-sightedness than other racial groups, meaning that the chances of childhood myopia are higher than for other groups. Indian and Caucasian children in Hong Kong schools have been found to be less prone to myopia than their Chinese counterparts, according to George Woo Chi-shing, chair professor of optometry at the Polytechnic University. What had rocketed in recent years, however, was the rate of environmentally induced myopia, particularly people who became short-sighted at a later age because of their work environments, Professor Woo said. '[Since] the introduction of computers to the workplace the prevalence of myopia has increased dramatically,' he said. 'We are getting so-called adult onset myopia which didn't exist in the old days until computers came into use. 'Before, it was very rare for people to develop myopia after they had got past the age of 21 or 22. It only ever used to happen to graduate students, lawyers and accountants.' Studies on different generations of Hong Kong families have found that parents and grandparents are far less prone to myopia than the current generation, but that Chinese people in general are more likely to suffer from short-sightedness. 'Wherever there are Chinese people, there is myopia,' Professor Woo said. 'Even if they are overseas Chinese, the incidence is far higher than for other racial groups.' The exceptions tended to be in rural parts of China. 'In rural areas the prevalence is very different compared to cities and urban areas,' Professor Woo said. 'Peasant farmers working in rice paddies are not myopic.' Conversely, rates are higher among Hong Kong Chinese people than other Chinese communities because of the city's densely populated, high-rise urban environment. 'It is to do with the lighting and living conditions - the close environment,' Professor Woo said. 'Rooms are so small and lighting is so poor, and those factors accentuate the problem. People are living in homes of 500 square feet accommodating families of four to five people.' While there is little evidence to suggest that health and eyesight are linked, Professor Woo said certain traditional Chinese medicines and foods that were rich in vitamin A had been proven to help eyesight. For office workers, screen breaks and 'eye exercises' in which people focus on a distant object to prevent the loss of longer vision are thought to help offset the advance of myopia. The first symptom of short-sightedness is likely to be a few seconds of blurry vision, or pseudo-myopia, when you look at more distant objects after working at a computer screen. That blurry vision is often a portent of permanent short-sightedness. Professor Woo said he believed the government should be putting more money into research. 'The increase in myopia is epidemic. The Singapore government is funding all sorts of research to address the problem, but the Hong Kong government isn't.'