To quote, and I'm sure this is hyperbole to some extent, "everyone in the sorority has it, and has tested positive for it, but we all are sworn to secrecy and don't report it because we don't want the school to send us home."

I'm sure there's at least a grain of truth to this. The numbers are certainly higher than are being reported in the news. And I'd bet even the school administrators themselves are aware that the numbers are truly much higher.