THE number of reported child sexual abuse cases has increased by 66 per cent this year, with some victims as young as four, prompting the Government to launch a public education exercise. Latest figures from the Social Welfare Department show that in June this year social workers handled 48 cases where children had been sexually abused, compared with 29 in the same month last year. The department's Assistant Director (Family and Child Welfare), Patricia Chu Yeung Pak-yu, said the increase in reported cases reflected growing public concern about child abuse. ''The number is on the increase, but we cannot definitely say if the problem is becoming very serious or not. More people are aware of the problem and willing to speak up,'' she said. ''This is a very good sign as it is better to have the problem known earlier and provide the necessary treatment to avoid the child suffering further.'' The department's senior clinical psychologist, Patrick Yau Dick-wah, said the cases they encountered involved boys and girls as young as four and as old as 15. He said the cases were discovered by people like teachers or social workers, or when the child grew up enough to realised he/she had been sexually abused. He believed the real number of child sexual abuse cases - including fondling, pornographic activity, incest or rape - was higher. ''Families caught in these cases have to face a lot of pressure. If the father is the abuser but also the sole bread-winner, then the family may hesitate to report to police as it may result in losing their financial support with the father taken to jail,'' Mr Yau said. Priscilla Lui Tsang Sun-kai, director of a children's welfare group Against Child Abuse, said child sexual abuse cases were still regarded by many people as ''shameful''. ''More public education is needed,'' Mrs Lui said. The co-ordinator of the Social Welfare Department's Child Protection Services Unit, Li Yuk-san, agreed and said the department was printing a brochure to be distributed early next year to educate the public to report child sexual abuse cases. The department has also handed out a guide to its staff, teachers and social workers to help them to identify cases of child abuse - physical, psychological and sexual - as well as neglect. Mr Yau said single-parent families and families whose parents had marital problems - including sexual difficulties or a history of being abused - were more open to child abuse. The assistant director said the amended Protection of Children and Juveniles Ordinance, which became effective on November 1, could help combat child abuse. ''The amendments have widened the circumstances in which a child or juvenile may be considered to be in need of care or protection to encompass children or juveniles suspected to be suffering from psychological and emotional abuse,'' Mrs Chu said. Latest figures from the Social Welfare Department showed they handled 477 child abuse cases in June this year, compared with 466 in June last year. The department also handled 365 cases of physical abuse, 23 cases of neglect, 11 cases psychological abuse and 30 cases of multiple abuse last June.