Plasma HIV RNA level and its effect on transmission to infants among pregnant mothers on ART/prophylaxis

Abstract

Background: Antiretroviral drugs, during and after pregnancy can reduce the risk of HIV transmission from pregnant women to their infants. This study was aimed to assess the association of plasma HIV RNA level and risk of transmission among pregnant women who are on Antiretroviral Therapy or prophylaxis.

Objective: To assess the association between the level of plasma HIV RNA and risk of transmission to their infants among pregnant women who were on ART or prophylaxis.

Methods: Facility based prospective study was conducted among 3^rd trimester pregnant mothers who were on ART or prophylaxis from November, 2012 to November, 2013. Interview was done using a structured questionnaire and blood sample was collected for laboratory analysis and HIV DNA PCR was tested for the early infant diagnosis using the Amplicor HIV-1 DNA test. Additionally, retrospective data on CD4 counts and hematology were collected. HIV-1 viral load copies/ml was determined by quantifying the amount of HIV-1 RNA in plasma sample using m2000rt Real Time HIV-1 assay. Stata version 11 was used for data analysis. Statistical significance considered P<0.005.

Results: Twenty five pregnant mothers who were on prophylaxis and 25 who were on ART with their corresponding 48 infants were enrolled in this study. The mean ages for pregnant women on ART and on prophylaxis were 28.5± 3 years and 26.8±5.0 years, respectively. Among the ART group, 7(28%) of them had detectable viral load (mean viral load was 19,343.8 copies/ml). In the prophylaxis group, 21(84%) of them had detectable viral load (mean: 197,120 copies/ml). The mean CD4 T cells count was higher on individuals who were on prophylaxis (mean: 598.6 cells/ml) compared to those on ART (324.4 cells/ml) (p<0.001). The rate of protection for the mothers on prophylaxis was 92 % compared to 100 % for those on ART.

Conclusion: This finding confirms ART can reduce significantly the risk of HIV transmission from pregnant women to their infants and will benefit the health of their future pregnancy outcomes by suppressing their viral load.