quantative vs qualitative pcr(hcv)

Question

What is difference between hcv quantative pcr and hcv qualtative pcr? If hcv rna pcr quantative is undected then it will be possible to negative of hcv rna pcr qualitative ?

Answer

The qualitative test tell us yes or no -- is there really hepatitis C virus in the blood? The quantatative test gives us a number -- how many hep C viruses in the blood? There used to be more of a difference between the 2 tests, when the lower limit of detection differed between the 2 tests. So sometimes if the level of virus was low, the quantitative assay (type of test) could not detect the virus, and we could get a false negative result. It used to be that to diagnose low levels of virus, the qualitative test was better. Now in many parts of the world both assays (tests) can detect hep C at low levels.

Yes if the HCV RNA by PCR quantitative is undetectable then it is possible to have negative HCV RNA by PCR qualitative.