HIV Ireland has called for pre-exposure prophylaxis to be made available in Ireland through the Health Service Executive's general medical scheme.
The call comes as new figures show a total of 512 people were newly diagnosed as living with HIV in 2016, compared with 485 in 2015.
Provisional figures show that so far this year 217 people have been newly diagnosed as living with HIV.
Figures from the Health Protection Surveillance Centre show that is slightly down on the figure of 241 this time last year.
However HIV Ireland says it is still concerned by the high level of new diagnoses among men who have sex men.
To mark Irish Aids Day, HIV Ireland and the Gay Health Network has called for the introduction of pre-exposure prophylaxis as a key HIV prevention intervention.
PrEP is a daily medication to prevent HIV infection in someone who has been exposed to the virus.
The Gay Health Network says people are accessing the medication online which means there is no support for its appropriate use.