Have you ever been at risk of HIV? Most people think they haven't, and quite a few of you are wrong. In fact, around 25,000 of you in the UK are so wrong that you're walking around with HIV without knowing it. If you're one of those 25,000 (and let's face it, that's much better odds than winning the Lottery, which many of us hope to do) then you are risking your own health and life, and you may well be unwittingly putting others at risk too.

Friday was the start of England's first National HIV Testing Week. It's aimed at gay men and African people, because those are the two groups of people with the highest rates of HIV here. One gay man in ten in London, and one in twenty across the country, has HIV. For people born in Africa and living here, it's about the same. That's as high, or higher, than many of the countries which we think of as centres of the epidemic.

We believe that everyone in these communities who's sexually active, and anyone else who has reason to believe they've been at risk, should test for HIV. And retest annually, or more if you're changing partners more frequently.

Why is it important to test for HIV? For a start, hundreds of people a year still die here because they test too late. The earlier you know, the more you can do about it and these days the treatments are good enough to keep most people alive into old age. But it's also important because HIV treatment reduces your ability to pass the virus along and because most people, once they know they have HIV, take care not to transmit it. Most new HIV infections here in the UK are from people who haven't yet tested.

So HIV testing isn't just about getting care. It's also, alongside condoms, one of the best tools we have for preventing the spread of HIV. If we're serious about halting the spread of HIV - and here at Terrence Higgins Trust we're very serious indeed about that - then we need to encourage everyone who's been at risk to test. Knowing your status means taking control of your life, not letting your fears control you.

Testing is easy, widely available and you can often get results in under an hour. Do yourself a favour. Go to www.tht.org.uk/HIVtestingweek or call THT Direct on 0808 802 1221 to find out more about HIV and, if it's appropriate, where you can get a test locally.

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