The first case in Hong Kong of human immunodeficiency virus, the precursor to acquired immune deficiency syndrome, was confirmed 20 years ago this year. But even the government's own report on its efforts to the Legislative Council last month suggests how lucky the city has been to have escaped an outbreak.

'We have no intention of painting a rosy picture,' says Dr Lee Shui-shan of the Special Preventive Programme (SPP), who wrote much of the report titled The Government's Responses to HIV/Aids in Hong Kong 1984-2004.

'Many people at risk of HIV infection belong to vulnerable and often marginalised communities, including drug users, commercial sex workers and MSM [men who have sex with men],' the report says. 'Stigma and discrimination are the obstacles in the implementation of effective public health programmes.'

The report sets out actions taken over the past two decades and indicates challenges ahead. It was written mainly by Dr Lee and his team at the SPP, although sources indicate passages particularly critical of the government were deleted.

What does not come through from the report is any increased sense of urgency in Hong Kong's response to HIV/Aids. Certainly, the days have long passed when senior frontline health officials were flown by government helicopter to Victoria Prison when the first case of HIV was found within its walls.

'The generally low HIV rate could blunt the community's awareness and alertness, exposing one's vulnerability to infection,' the report says.

The rate is indeed low - less than 0.1 per cent. Consider, then, that Unaids figures show China has an overall low HIV prevalence among the adult population of less than 0.2 per cent.

Part of the low level of community alertness in Hong Kong may be the fault of Legco itself, which has had just one scheduled debate on HIV/Aids, and that was in 1993, according to a 2003 survey by the Secretariat of the Advisory Council on Aids.

The subject was raised in the course of council meetings and panels, and in questions to the administration, but there has been no concerted discussion in recent years. Nor has Legco pursued the government on its handling of Aids.

'The public looks upon Legco as a leader in policy development, whose debate has reflected the contemporary mindset as well as society's priorities,' the survey report says.

Health officials say that, in the absence of legislators willing to take an interest, there is little they can do other than lodge documents with Legco in the hope the issues they raise will be dealt with at some future time.

'Let's face it, it's not a high priority among legislators,' one official says.

Little wonder that Graham Smith, chief executive of Aids Concern, says 'there are serious weaknesses in the current system which could allow the HIV/Aids problem to escalate'.

Mr Smith says that ongoing surveillance among certain key vulnerable groups, such as men who have sex with men, and female sex workers 'is virtually non-existent'.

Also, HIV testing rates among vulnerable groups is extremely low, at less than 20 per cent. On that basis, the current infection numbers, now at more than 2,300, could be at least twice and as much as five times as high as the official figure.

Last year, the Department of Health, Prince of Wales Hospital and Queen Elizabeth Hospital carried out a total of 83,641 HIV tests, with 258 returning positive. In 2002, 96,244 tests were carried out, with 291 positive.

In June this year, the government launched the $1 billion Centre for Health Protection (CHP) to co-ordinate appropriate responses to public health issues in Hong Kong. The CHP, following in the steps of the mainland by grouping HIV/Aids with tuberculosis and sexually transmitted illness, ranks it as the fifth of 10 priorities.

The CHP promises only to 'develop intervention programmes targeting vulnerable communities to be determined based on research and trend analysis'. It says nothing about the intervention programmes already under way, nor the repeated calls from non-governmental organisations such as Aids Concern for ongoing funding for the research to conduct trend analysis that would help fine-tune the existing programmes.

The outbreak of severe acute respiratory syndrome (Sars) made it clear there are serious problems with Hong Kong's public health regime. However, health officials and Aids workers say the evidence of those problems could have easily been seen in its handling of HIV/Aids.

One disturbing example, cited by both Mr Smith and some health officials, are tests for sexually transmitted illnesses. Anyone not holding a Hong Kong identity card must pay a $700 testing fee. The object was apparently to stop illegal mainland sex workers in Hong Kong using public facilities. So, non-residents have vanished off the screen and no-one knows whether they are going home for treatment, using private health facilities, or simply not bothering, and so contribute to the further spread of infections.

Officials say that, from a public health point of view, such an approach to sex workers and their mainland clients would seem disastrous. The measure was introduced despite the strongest objections of health workers.

'We don't expect an epidemic to happen overnight,' says Dr Lee. 'But if we look at all those infections over the past 20 years, we can only congratulate ourselves because we haven't seen an epidemic yet.'

Aids Concern's outreach workers say they can't reach everyone, despite their best efforts in high-risk areas such as male saunas and border truck stops, as well as among young people. 'We know what the vulnerable groups are, but we don't know if the message is getting through,' says Mr Smith, who blames a 'lack of vision' at the decision-making level.

'If I had one wish, it would be that they are seriously looking ahead and there's some sense of urgency,' he says.

Aids Concern's work has attracted overseas attention, with non-governmental groups from around the region looking for the best ways to tackle specific HIV/Aids issues.

The group is, however, constrained by policy decisions handed down from above, which do not necessarily reflect what actually needs to be done.

The Advisory Council on Aids, which is due for a reshuffle next year, does not include anyone on the receiving end of its advice, such as doctors in the field, Aids workers, or even people with HIV.

In the absence of any top-level action until recently, Dr Lee and his colleagues have been working with the mainland at an unofficial level for nearly 10 years, mainly through local universities and public health agencies.

The demarcation between administration and profession makes official contact difficult, a problem Dr Lee hopes the CHP will resolve by according the small HIV/Aids teams higher status in the eyes of the bureaucracy.