Background: The ability to differentiate recent human immunodeficiency virus infections (infection within few months) from long-standing (established) infection is valuable for accurate measurement of the changing patterns of HIV transmission and disease management. We determined rates of recent and long-established HIV infection using anti-HIV avidity index (AI) immunoassay.Methods: We conducted the study using sequential serum samples from 100 HIV-1 positive patients. The time since infection was estimated using the automated third generation anti-HIV enzyme immunoassay [AxSYM HIV1/2gO Avidity Index (AI) assay] to discriminate between recent and long established. AI of ≤ 0.80 indicated recent infection.Results: The prevalence of recent infection was 11%. Age and sex were not associated with recent infection. The prevalence of those who were married with recent infection was (72.7%). The median CD4 of those recently infected was higher (364: IQR 31-600) cell count compared to those with long established infection was (134: 12-639) cell count. The median viral load of the study participants was higher among recent infection 99892 copies/ml while long established infection was lower 62971 copies/ml.Conclusion: The use of AI clearly has a potentially important role in early diagnosis of HIV infection, discriminate recent from long-established infection among individuals and understanding of HIV/AIDS epidemic for public health interventions in resource-limited settings where the disease burden is highest.Keywords: Avidity Index, HIV Infection, Late, Recent
