The number of New Zealanders being diagnosed with HIV has reached a record high, and it can't be put down to increased testing.

Figures released today by Otago University's AIDS Epidemiology Group show 244 people were diagnosed with HIV last year, the highest number since records began in 1985.

The number of people who contracted HIV in gay relationships in New Zealand was also the highest since records began.

Group leader Dr Sue McAllister said most people are getting diagnosed with HIV relatively quickly, which means rates of infection are increasing too.

"They're not people who may have been infected several years ago and only now being diagnosed, they are reasonably recent infections."

Dr McAllister said the stigma around HIV can discourage people from getting tested or taking preventative measures.

"Continued use of condoms, early testing, early access to anti-retro-viral treatments, screening for other sexually transmitted infections."

She said new prevention methods, like giving HIV medication to high-risk uninfected people, are being trialled overseas.

HIV is now treatable, but is a lifelong condition with significant health implications, Dr McAllister said.