A taxpayer-funded drug to prevent you contracting HIV.

Labour says it will fund this drug if it's in government.

So if you're the most at-risk group of contracting HIV -- that's homosexual or bisexual men -- you will be able to access this drug.

You take it, and you're 92 per cent less likely to contract HIV.

Labour announced this at the Big Gay Out - and for a reason.

The number of people diagnosed with HIV in this country is increasing -- in the 1990s, typically fewer than 100 people a year were diagnosed with it.

Then, it spiked in the 2000s, before dropping off again six years ago to around 109 new cases.

But it's been rising ever since and rising significantly.

In 2015, there were 224 new cases of HIV.

The New Zealand Aids Foundation says for each new diagnosis it will cost the government between half a million and $600,000 in treatment over the course of that person's life.

This preventative drug -- it's called Prep -- will cost around $10,000 to $12,000 per patient, per year, to fund.

There's been some research on this in Australia. There it's believed they could halve the rate of new infections if Prep was offered to those who need it most.

In New South Wales, health authorities are already offering it to about 4000 gay men.

In Western Australia, they're trialing it.

I was reading this morning about the Dean Street Clinic in London -- it's the largest sexual health clinic in the UK. In the last year, it's seen an unprecedented 40 per cent drop in new HIV diagnoses in the last year.

And the clinic says that is in part because of this drug -- Prep.

It seems a no-brainer, doesn't it, to fund this drug for those most at risk.

If you want to reduce the expensive taxpayer spend on HIV treatment, then you need to fund this drug.

It's an issue that's easy to politically side-step, particularly if you're a national government.

And to be fair to Bill English, he did engage in a conversation about prep at the big gay out this weekend.

But the latest statistics show 224 people were diagnosed with HIV in this country in a the course of a year -- and at a minimum cost of half a million dollars to treat each of those cases, funding the preventative drug to those most at risk surely makes sense.