The health ministry said that, Argentina's AIDS population is aging, citing statistics showing one in five AIDS patients in the country is over 45, up from seven percent a decade ago.
"Increasingly more adults are turning up, 45 or 50 years old, newly infected," said Carlos Falistocco, head of the ministry's office on AIDS and sexually transmitted diseases.
Falistocco said this segment of the population has not typically been targeted by awareness campaigns on how to prevent and treat HIV, the virus that causes AIDS.
"You have to run specific campaigns for this group, so they will feel represented and identify with the disease," he said.
These are not the AIDS patients you see "on television or in health campaigns, but they are there in real life, in the statistics, and that is worrying," he said.
According to infectious disease researcher Patricia Patterson, the older generation "discarded condoms because they don't believe they are at risk."
Because of this, "half don't know they have AIDS and are diagnosed only after they are already very ill," she told the "Profile" newspaper.
In recent years, the number of new cases in Argentina has remained stable at around 5,500 each year. But it is estimated that as many as 40 percent of those infected have not been tested.
Sexual transmission remains the most common vector for new infections, with 90 percent of new cases contracted through unprotected sex.
According to ministry figures, there are 110,000 people living with AIDS in Argentina, of whom 1,400 die each year.