Patent ID: 7442497

Claim:
A method of determining the probability of whether or not an individual has chronic HCV infection or has cleared said infection comprising the steps of: obtaining a fluid sample from the individual; performing an antibody-based assay on said sample, said assay including contacting said sample with a plurality of different HCV antigens reactive with different antibodies and detecting interactions between the antigens and antibodies from the sample; determining the optical density of said sample after said antibody-based assay is performed and with said plurality of different HCV antigens present in said sample; and using the optical density to determine the probability of whether the individual has chronic HCV infection by comparing the determined optical density with a correlation curve based on the optical densities of fluid samples in combination with HCV antigen from HCV antibody-based assays from individuals having chronic HCV infection and individuals that have cleared the HCV infection but still test positive for HCV antibodies, said method permitting a prediction having at least an 80% probability that the individual providing said fluid sample has chronic HCV infection when said optical density is greater than about 3.0 at 450 nm in comparison to a negative control which must have an optical density of 0.1 or less at 660 nm.