Fingers should never touch the inside of the Stericup. Any bacteria, fungi or viruses present on the surface of the skin may contaminate the solution. The Hepatitis C virus can survive in traces of blood present on the skin or on any surface, even if they are invisible.
Never reuse, share or draw-up after someone. Even if it has been cleaned, the spoon can still contain viruses from someone else's syringe, filter, water or fingers.