The number of gay and bisexual men diagnosed with HIV has reached the highest level ever recorded in Ireland, new figures show.

According to Ireland’s Health Protection Surveillance Centre (HPSC), the number of new cases has been “rising steeply” since 2008 and reached record levels in 2012.

166 gay men were diagnosed with HIV in 2012 compared to 131 heterosexuals and 14 intravenous drug users. Although figures have not been completed for 2013 the HPSC warns “this increasing trend has continued” with 82 gay men diagnosed for the first time in the first six months of last year.

Almost half of those who contracted HIV in 2012 tested negative for the infection in the previous 12 months. The average age of newly diagnosed men was 31, with the biggest increase in the 20-29 age group.

The majority had no symptoms at the time of their HIV diagnosis but took the test because they were having a screen for sexually transmitted infectionS, had engaged in risky sexual behaviour or had an infected partner.

The study found that men aged 50 and older were much more likely to have symptoms related to HIV at the time of their diagnosis and had taken the test for that reason.