Trichomonas is not a virus but rather is a parasite. Most men are asymptomatic. I recommend that you and your partner be treated by your Doctor the retested later for cure. Take care.
My understanding is that the virus can lay dormat for some time and men are almost always asymptomatic. They rarely show any signs of having this virus which is part of the reason its so hard to stop. Everybody is different. It could've laid dormat in anybody that long, not just him.