I like it, it triggers that paranoia that the little tickles and such you feel every once in a while could be more then just a figment of your imagination, that the creepy crawlies really are on you. Just a couple of wording issues I think;
"On the second day, twenty-four hour (24) to forty-eight (48) hours after exposure,"
You switch back and forth between notations between hours and days. It might be better to stick with one or the other.
"Subjects normally are not alarmed at this stage, and only casually notice the ants before removing them from their person."
This perhaps could be rephrased more scientifically, alternately you could likely create a short testing log and remove the subject's observations from the effect of the SCP and place them there.
So the effect under the description would simply be the growing number of more and more aggressive ants. Afterwords there would be a testing/observation log where a subject is deliberately effected, then their observations and reactions are recorded.
