I find the assertion implausible. You wouldn't need to go to Argentina to study the sex habits of homosexuals. We have plenty right here in the U.S.

The NIH has worked with Argentinian health officials in AIDs prevention. I found mention of this on this right wing site and some right wing blogs. I'm afraid that doesn't make the story factual or even plausible.

Might some of these people (they aren't journalists) be exaggerating a wee bit?