Seroprevalence of human immunodeficiency virus in north Indian blood donors using third and fourth generation Enzyme linked immunosorbent assay

BACKGROUND: The percentage of HIV cases attributable to blood transfusion has decreased significantly in the last decade. The newer 4(th) generation Enzyme linked immunosorbent assay (ELISA) has been shown to have increased sensitivity compared to 3(rd) generation ELISA. OBJECTIVES: To estimate the seroprevalence of HIV among blood donors using 4(th) generation ELISA assay and to compare it with the 3(rd) generation ELISA. MATERIALS AND METHODS: This prospective study involved 10,200 blood donors- 6,800 were voluntary donors (3400-students and 3400-non students) and 3400 were replacement donors. All blood units were tested with 3(rd) as well as 4(th) generation ELISA. All samples found reactive or in grey zone with either 3(rd) or 4(th) generation ELISA were retested by Western blot (WB). RESULTS: The seroprevalence of HIV was estimated to be 1.37/1000 donations (0.14%) with 3(rd) generation ELISA compared to 3.62/1000 donations (0.36%) with 4(th) generation ELISA (p>0.05). The seroprevalence of HIV among voluntary donors was estimated to be 1.32/1000 donations (0.13%) with 3(rd) generation ELISA and 3.67/1000 donations (0.36%) with 4(th) generation ELISA. The prevalence of HIV among replacement donors was 1.47/1000 donations (0.15%) with 3(rd) generation ELISA and 3.52/1000 donations (0.35%) with 4(th) generation ELISA. CONCLUSION: 4(th) generation HIV ELISA detects a higher number of seroreactive donors compared to 3(rd) generation ELISA. However, larger studies are required with confirmatory tests for both 3(rd) and 4(th) generation ELISA for making any policy changes.