The terrible physical abuse of a seven-year-old girl, apparently at the hands of her family, makes plain that the safeguards Hong Kong has in place are not enough. A teacher noticed bruises and that the child was underweight, but did nothing; the girl's pitiful state was ignored by all who encountered her. Social workers never got to see her and were lied to by her parents, but there was no suspicion. Only when she was admitted to hospital, unconscious, malnourished and suffering from sores and scars, was the alarm raised.

That was more than a month ago and the girl, who came to Hong Kong from the mainland last November to live with her parents and siblings, remains in hospital, brain damaged, unable to talk and being spoon fed. When admitted, she had gangrene, was severely underweight and her body was scarred by abrasions, ulcers and bed sores. Kindergarten staff had noticed marks on her legs in April, but her mother withdrew her from the school. Police were never alerted; no call was made to a Social Welfare Department child abuse hotline.

The girl's parents and 15-year-old twin half-sisters were arrested and are free on bail. A six-year-old brother and the sisters have been put in child custody. It is bewildering that these moves took place only last week instead of months ago.

Such cases come to light from time to time. It is surprising that they occur in a city so crowded and with such cramped living conditions, where there is so little privacy. Yet it seems that even when a child is obviously being abused, neighbours as much as strangers are willing to look the other way. Government hotlines and police are of no use in such a hear-no-evil, see-no-evil environment.

Hong Kong is not alone in this respect; child abuse often gets deliberately ignored due to the sensitivities of getting involved in other people's affairs. But there is nothing more repugnant than an adult abusing those too weak or young to fight back. The physical scars may heal, but there may never be a recovery from the mental ones. Communities have to deal with that life-long damage, so prevention is a necessity.

Child rights advocates believe Hong Kong needs a comprehensive protection system. One proposal is to adopt rules set by some other governments legally obligating professionals like doctors, nurses and teachers to report suspected abuse to child protection officials. At the least, authorities need to review procedures.