Viral load refers to the number of viral genomes present in a patient sample. The measurement of viral load has become important with the increased amount of antiviral medications being created. Clinically, viral load is extremely important in the monitoring and treatment of patients suffering from HIV, hepatitis B and C, and CMV. Tracking the viral load in patient samples can detect the efficiency of antiviral therapy, show potential medication resistance, and indicate possible relapses.
Determining viral load is also important for transplant patients. Viral pathogens have a detrimental effect on transplant recipients and antiviral medication is often used to prevent transmission or slow progression of viruses. The use of real-time PCR provides a rapid turnaround time that is crucial when treating and monitoring transplant recipients.
To determine viral load through real-time PCR, a quantitation standard of known value is incorporated into each value. Such standards are generally included in real-time PCR kits. The results of both the viral and standard amplicons are compared with a standard dilution curve which will then establish the viral load.