I think you'll find Hepc is primarily transmitted by blood, it has only a very low sexually transmitted risk if any. The virius like all hepatitis virus effect the liver. Prisoners are high risk because of using blood contaminated shared needles.
HIV is not related to Hepc except that it is also transmitted by blood as well as somebody fluids.
Any one who donates blood is screened for HepC & HIV amongst many other virius.
Hope this helps.