Assessment of HTLV-I proviral load, HIV viral load and CD4 T cell count in infected subjects; with an emphasis on viral replication in co-infection

Objective(s): HTLV-I and HIV virus quantification is an important marker for assessment of virus activities. Since there is a direct relationship between the number of virus and disease progression, HTLV-I and HIV co-infection might have an influence on the development of viral associated diseases, thus, viral replication of these viruses and co-infection were evaluated. Materials and Methods: In this study, 40 subjects were selected; 14 HIV infected, 20 HTLV-I infected and 6 HTLV-I/HIV co-infected subjects. The amount of viruses was measured using qPCR TaqMan method and CD4 and CD8 lymphocytes were assessed by flow cytometry. Results: The mean viral load of HIV infected subjects and HTLV-I infected individuals were 134626.07±60031.07 copies/ml and 373.6±143.3 copies/104 cells, respectively. The mean HIV viral load in co-infected group was 158947±78203.59 copies/ml which is higher than HIV infected group. The mean proviral load of HTLV-I in co-infected group was 222.33±82.56 copies/ml which is lower than HTLV-I infected group (P<0.05). Also, the mean white blood cell count was higher in co-infected group (5666.67±1146.49 cells/μl). However, the differences between these subjects did not reach to a statistical significance within 95% confidence interval level (P =0.1). No significant differences were observed regarding CD4 and CD8 positive lymphocytes between these groups. Conclusion: HTLV-I/HIV co-infection might promote HIV replication and could reduce the HTLV-I proviral load, in infected cells. Considering the presence of both viruses in Khorasan provinces, it encourages researchers and health administrators to have a better understanding of co-infection outcome.