Except people normally don't dismiss quarantines. They just did it for this particular disease.

Is that the case? We're happy to quarantine highly-transmittable diseases, but HIV isn't -- it takes significantly more than shaking a hand or coughing to transmit. Indeed, even with easily transmitted conditions like tuberculosis, we go for involuntary quarantine only during emergencies or as a last resort. Most carriers are only required to wear masks and avoid certain types of work.