The first-world people with access to world class health care that contracted it in urban environments were gay. Origins however, are a bit more murky.
Most of the worlds population don't have the financial resources or the proximity to say, the UCSF medical hospital, where such specialty physicians would be to study such a thing.
There's been quite a bit of discussion of how it got to Christopher Street in New York. My pet theory is that the international drug trade had quite a bit to do with it, but I'm just a computer programmer
From Wiki:
At one point, the CDC coined the phrase "the 4H disease", since the syndrome seemed to affect Haitians, homosexuals, hemophiliacs, and heroin users. In the general press, the term "GRID", which stood for gay-related immune deficiency, had been coined.[180] However, after determining that AIDS was not isolated to the gay community,[178] it was realized that the term GRID was misleading and the term AIDS was introduced at a meeting in July 1982.[181] By September 1982 the CDC started referring to the disease as AIDS.[182]
Most of the worlds population don't have the financial resources or the proximity to say, the UCSF medical hospital, where such specialty physicians would be to study such a thing.
There's been quite a bit of discussion of how it got to Christopher Street in New York. My pet theory is that the international drug trade had quite a bit to do with it, but I'm just a computer programmer