In 2005 there was one new infection among men having sex with men every four days.
There were 89 new HIV diagnoses for the year, a nearly one-fifth increase on the previous highest figure in 2004.
Almost all these new infections were contracted in New Zealand, and almost all in the North Island.
Three out of every four new HIV diagnoses reported were from men having sex with men in Auckland.
The foundation told a forum of gay and lesbian Aucklanders that the rate of new HIV infections since 2000 was due in large part to the growth of Internet hookups, the increasing pool of relatively healthy HIV positive people – both those who know they have the virus and those who remain unaware.
The destigmatisation of homosexuality may have also led to an increase in casual sex by bisexual men.
The foundation raised concerns about the number of sexually active men who remain naive about the dangers of HIV, through not accessing traditional gay media and venues.
"Condoms are wonderfully successful in protecting against HIV," said foundation research manager Tony Hughes, "but it is clear by the highest rates of new infection detected since the beginning of the deadly epidemic that the need for condoms is not reaching many men."