IN his letter in the South China Morning Post of July 30 under the headline, ''Get your act together'', Dr Chris Lund made a number of remarks about our blood test service, particularly relating to the time required for our test results to be known, our pre-and post-test counselling and the non-inclusion of the testing of hepatitis B and syphilis in our service. He also remarked that we do not supply written reports of the results to our clients and that our clients have to attend our centre personally for the results. To enable Dr Lund and your readers to better understand our blood test service I would like to take this opportunity to explain more fully its purpose and arrangements. Our free blood test service is provided on an informed, voluntary and anonymous basis and is provided only to people who, for one reason or another, have been at risk of HIV infection. Our service enables these people to know of their HIV status without fear of being subjected to prejudice, discrimination or known by other people, and so that they could seek appropriate medical treatment and advice, if necessary, and avoid being infected/further infected or infecting others unwittingly. The purpose of our blood test service is not to provide certification, which is rather misleading anyway, not least because of the window period during which no HIV-antibody can be detected despite infection. Thus before we provide our service we would establish our client's need for it and make sure that he or she understands the implications of an HIV-antibody test, apart from explaining to him or her the nature and arrangements of our service. This is the rationale behind our pre-test counselling and we consider it essential to any HIV-antibody tests. Post-test counselling is even more important. The need for it is obvious in the case of positive results, but even for negative results counselling is still essential, because the results are no proof of the clients' present HIV status. Besides, they might give people the false impression that they could continue with their risk behaviour. We have encountered many clients who felt that all they wanted were the results. We fully understand their feelings, but strongly believe that any HIV anti-body test must be accompanied by pre-and post-test counselling if the test is to achieve a preventive purpose. Dr Lund said that such counselling could be done by any family physician. While I would not query this, I hope the public would understand that our service is meant to provide a free, non-governmental alternative to those who need the service. Regarding the duration required to get the results, we doubt very much that the results of a confirmatory HIV-antibody testing could be available within a day as claimed by Dr Lund. While the results of the preliminary test (ELISA), which is very sensitive and could yield false positive results, might be known within a day, those of the confirmatory test would need a few more days to be obtained. In our case we rely on the Government's laboratory support, which is being generously provided to us free of charge. Blood samples taken in our centre are transported to Queen Mary Hospital every Wednesday and Friday (our services sessions being held every Tuesday and Thursday evening), when any known results are also collected. Thus, the normal duration for us to know the results would be seven days and we allow for up to 10 days just in case there is any delay. On the waiting time for our service, although it has so far been almost fully subscribed, our clients rarely need to wait for 30 minutes to be received by our volunteers or staff. In Dr Lund's case I understand that he was early by half an hour for his appointment. As an organisation whose main object is to fight AIDS, we do not feel it appropriate, at least not at this stage, to be engaged in activities not directly related to our objects, such as testing for hepatitis B and syphilis, which do not require the samelevel of confidentiality and anonymity as HIV in making the testing arrangements. On our relationship with AIDS Concern, Dr Lund may wish to know that both our Foundation and AIDS Concern believe in greater co-operation between the two organisations and are working towards this goal. Finally, I wish to stress that we welcome any feedback from our clients and the public, which could only help us to improve the standard of our service. FREDERICK TONG Chief Executive Hong Kong AIDS Foundation