TODAY'S revelation that traces of cholera were found in a fish tank in a Wan Chai restaurant and in sea water at the Causeway Bay typhoon shelter should provoke outrage. People in Hong Kong, not unreasonably, assume that public health controls are supposed to be stringent enough to enable them to enjoy a seafood meal without running the risk of catching cholera or some other serious illness. Yet the Government's disgraceful negligence in that regard is graphically illustrated by the fact that even its own markets are a potential source of the deadly disease. Throughout the week, as more cases of cholera were reported, officials continued to downplay the problem. On Friday, Governor Chris Patten stepped in promising to make it a top priority. Yesterday, there was a decidedly sharper edge to the pledges from top Government officials, possibly in response to Mr Patten's personal interest, or the result of our latest revelations. Whatever the reasons behind the sudden gear shift, promises must now be accompanied by urgent action. An immediate ban on the use of contaminated typhoon shelter sea water to store fish must be the top priority. Water from typhoon shelters - the cause of the present outbreak - should also be declared off limits to those trading in water. Notices should be erected warning that the water is infected, and anyone caught filling up tankers from them should be questioned and, if necessary, detained and even fined. Licensing conditions need to be imposed on restaurants to store fish under the same stringent requirements that apply to other foods. Filtration methods such as ultraviolet machines should be made compulsory to neutralise harmful bacteria and disease and ensure a clean and safe flow of water in fish tanks. Safer sources of water should also be identified so that all live seafood can be stored in water of acceptable quality. These should go hand in hand with proper monitoring mechanisms. The tight controls on food coming across the border from Shenzhen show what can be done, and should now also be applied to seafood brought ashore in Hong Kong. If the Government lacks the power to implement such essential measures, then legislators, who have rightly attacked the Government for dragging its feet on the issue, should be reconvened to pass the necessary legislation. That such steps have not already been taken is a disgrace which Mr Patten would do well to investigate. Part of the problem is that no department or official has been prepared to take responsibility. Instead a tangle of government arms ranging from the Health and Welfare Branch to the Urban Services Department have been busier deflecting the issue. That must now change. The buck must stop somewhere in the administration. If the Governor deemed rising property prices important enough to set up a high-powered task force to tackle the problem, then surely preventing a cholera epidemic deserves no less. It is not just a matter of bringing the present outbreak under control. Once cholera cases stop being admitted to hospital, steps must be taken to tackle the problem at source. That means speeding up the sewerage plan strategy to treat Hong Kong's heavily polluted waters as the long-term solution. If the Governor is indeed serious in his pledge to make this his top priority, he should implement such a plan of action without further delay. Public health is not the only issue at stake. In the longer term, failure to stop the use of polluted sea water to store live seafood will hurt the tourist industry and the territory's international image as a modern, clean city.