breeding-ground

A place or region where animals go to breed.

A place or institution seen as creating large numbers of a stated thing, type of person, etc.

Harris criticized the report's emphasis on enforcement, noting that, "Putting people in jail won't stop the virus from spreading." In fact, prisons are virtual breeding grounds for AIDS, due to lack of safer sex and safer drug use education, condoms and uncontaminated needles.

Echoing Allen Ginsberg, he contends that the suburban setting of “Father Knows Best” is most accurately seen as America's “ludicrous breeding ground for the young meat who will be fed into its wars and rat races and inhuman conformities.”