It seems that this happens every year before the Olympics. 8 and 9 years ago, they nailed a truckload of Chinese in a dragnet after the 1994 World Swimming Championships, and 4 years ago, 39-year-olds Merlene Ottey and Linford Christie, and 34-year-old Dieter Baumann were the victims of nandrolone testing (with only Ottey coming out of it unscathed and running in Sydney, 4th in the 100). Now, modafinil and THG seem to be the test case for this year and next year.
In the cases of Calvin Harrison, Chryste Gaines and Regina Jacobs, one can only wait, and hope that B-sample comes up clean. This could almost certainly end their careers, and with Chryste and Regina having won a ton of medals in countless world events, I'd hate to think that their careers would end on a note as sour as this.