Determination of HCV infection stage in a group of seropositive patients from Maracaibo, Venezuela by measurement the antibody avidity index of anti-HCV IgG

To identify HCV infection stage in a group of seropositive patients from Maracaibo, Venezuela, using the measurement of IgG antibody avidity technique. We used a modification suggest by Leon et. al.(1997) of the normal protocol of ELISA Ortho HCV 3.0 Kit. This protocol modification was make two parallel assays for each sample adding new wash step using 6M Urea for one of parallel assays. The average AI (Avidity index) of 19 HCV seropositive patients found was 55 +/- 23,8%. Also, it was found that three (15,79%) of these patients were in primoinfection stage by HCV, seven (36,84%) were in past o chronic stage and nine (47,36%) were in chronic stage. The new cases ratio calculated for the investigation period was 1/5, this mean that for each five patients diagnosed with HCV, only one was in the acute phase of infection. Data from this study provides new information about epidemiology of HCV in the area.