He was one of three doctors that Doctor Phlox approached to see if any progress had been made in curing Pa'nar Syndrome. Sub-Commander T'Pol had contracted this disease through a mind meld, and because of the Vulcan prejudice towards mind melders, it had to be kept a secret.
Oratt and the other doctors discovered that T'Pol was infected and intended to recall her to Vulcan. But one of the doctors, Yuris, admitted to being a mind melder himself and interceded on T'Pol's behalf. Dr. Oratt allowed T'Pol to remain aboard Enterprise NX-01, but informed Dr. Yuris that he would lose his standing in the Medical Exchange. (ENT: "Stigma")