Warning images on cigarette packets are the strongest deterrent against smoking, but these are only effective for less than half of the 47,000 students who took part in a recent survey. The Committee on Youth Smoking Prevention survey also found that these images had no effect on more than 77 per cent of smokers in the group. Most interviewees said the images on the packets appeared even less intimidating after a period of time if they were not changed. 'The government should use less symbolic and more realistic photos, and change them regularly,' said Li Cheong-lung, chief executive of the committee. He recommended that the government grant this authority to the director of health. Of the students surveyed, 4.2 per cent had smoked in the 30 days before the survey - a reminder of the increasing number of teenage smokers, despite the small number of teachers who were smokers and the anti-smoking programmes already in place in schools. Mr Li also suggested that the government use part of the tax revenue from cigarette sales, which currently goes to the Treasury, to cover the cost of anti-smoking programmes in schools. He believes these schemes can help stop students from smoking. 'The cigarette tax hike may have boosted the number of long-time smokers who wanted to kick the habit, but more needs to be done to minimise the number of young people picking up the habit,' Mr Li said.