I write a lot on this blog about attitudes to HIV. In many ways, changing the way in which people think about HIV is now one of the most challenging things we do. We know that our medicines work well, our patient pathways are excellent, and increasingly people with HIV are living long, healthy lives.
But stigma still exists and, although not as bad as in China (another story, another blog) and the UK and USA in the early 1980s, it remains endemic in this country, among all levels of society, and can be really damaging.
The next piece to the HIV puzzle in many ways, then, is about changing public perceptions. Out-of-date and negative attitudes to HIV can dissuade people from testing - and that's why one in four of those with HIV in the UK are not aware of their status.
That's a really dangerous statistic. It means there are 25,000 people in the UK alone who are going to get sicker than they need to or indeed die. It also means that people are continuing to infect others with HIV without knowing it. The people who die of HIV in this country today are those who have not been tested - or who have been tested but diagnosed too late for treatment to be successful. Testing really can save lives.
That's why the recent announcements from the Chief Medical Officer, Dame Sally Davies, are so encouraging. First, the news that those Doctors and dentists living with HIV are no longer to be barred from undertaking certain jobs or procedures in the workplace - dentistry, for instance, or surgery - sends a very strong message .
Not only that, but legislation is now following data - not hysteria or deeply ingrained perceptions and fears.
People living with HIV who are on stable, effective treatment have undetectable levels of virus in their blood. That means the chances of becoming infected by a needle stick injury from an HIV positive healthcare worker on treatment are around the same as being stuck by lightning - essentially it is simply not going to happen.
How effective is treatment at preventing transmission? Extremely. This is a slightly different scenario, but for the purposes of illustration consider for a moment childbirth: a fairly prolonged, bloody experience for the baby. If a mother with HIV has an undetectable viral load at the time of vaginal delivery, however, the chances of her passing on HIV to her baby at the time of birth is less than 0.1%.
Think of the baby as "the patient" for a moment and the mother as the healthcare professional [HCP]. Never in your wildest dreams would any HCP expose any patient to that amount of their own blood, even without the existence of universal safety procedures and gloves.
Again, this is for illustration purposes only - but the stats and facts remain. There have only ever been four documented cases worldwide since the beginning of the epidemic 30 years ago in which an HIV positive healthcare worker infected a patient. Those cases involved individuals in the early days of HIV, before effective treatment was available. Things have moved on.
Lifting the ban on HIV-positive doctors, nurses and dentists tells the public this. It allows our health policy to catch up with scientific fact: you are simply not going to catch HIV from your nurse, dentist or doctor.
In fact, the risk of transmission of HIV from the public to healthcare professionals is infinitely higher than the other way around. As the majority of the population have not been tested, it is the person with undiagnosed HIV and is therefore not on treatment who is truly infectious. That's why we need to improve testing take-up - to protect all of us from the real danger.
We can combat stigma with gestures and symbols. Role models and educators can change the tone of the debate, which is why we are so grateful to our footballing and sporting advocates. Advocacy is crucial to tackling prejudice and persuading people that HIV isn't a dirty secret, but a manageable condition.
But a change in legislation based on robust scientific rationale could just be the tipping point in really trying to change public attitudes.
The more we normalise HIV and HIV testing, the better it will be for everyone. An HIV-positive dentist who has been diagnosed and is on treatment is no threat to anyone. A person with undiagnosed HIV puts their own health in jeopardy as well as that of their sexual partners and healthcare professionals.
So. Let's test all health care professionals and all patients. That way we may be able to save lives and fight stigma, all at the same time.