The over-50s infection rate in England, Wales and Northern Ireland more than doubled in under a decade – from 299 new cases in 2000 to 710 in 2007.
In 2008 there were 7,382 new diagnoses – 8% of these were in the over-50s, says the Health Protection Agency.
Experts say the figures are a stark reminder of the importance of practising safe sex, whatever your age.
Other sexually transmitted infections have shown a similar doubling in under a decade among the same age group, and have been rising at a faster rate than in the young.
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Full story: BBC News – HIV rate rises among over-50s