What does borderline hepatitis c mean from blood work?

I recently had blood work done through my VA, and it says my hep c results were borderline and they will test me again in 4 weeks. Also my ALT and AST are normal. I have no idea what this means, but there really is no way, or any event i can recollect, of me even being in contact with blood, unless somehow it happened on my unsanitary deployment. Are there often mistakes? And how can a result be borderline?