CROI 2017 Abstract e-Book

Abstract eBook

Poster and Themed Discussion Abstracts

HIV DNA PCR is shown in table 1. Thirty-three infants in high-risk group (59%) were HIV DNA PCR positive at the first sample, compared to 21 standard risk infants(95%) (p=0.001). Among high-risk infants, 12(21%) were initially HIV DNA PCR positive by the 2nd sample by 2 month of age, and 11(20%) by samples collected between 2-6 month of age. Conclusion: Combination antiretroviral neonatal prophylaxis regimen may delay the time to HIV DNA detection. False negative HIV DNA PCR testing was observed in about 40% of high-risk HIV-infected infants tested at one month and 20% at two months. Therefore, to exclude HIV-infection in infants on triple antiretroviral prophylaxis, negative HIV DNA PCR should be documented when infants are at least 4 months of age.

794 HIV VIRAL-LOAD TRENDS WITHIN SOUTH AFRICA’S EARLY INFANT DIAGNOSIS PROGRAM, 2010–2015

Ahmad Haeri Mazanderani 1 , Faith Moyo 1 , Tendesayi Kufa-Chakezha 1 , Gayle G. Sherman 2 1 NCID, Johannesburg, South Africa, 2 Univ of the Witwatersrand, Johannesburg, South Africa

Background: Within South Africa’s PMTCT program, maternal antiretroviral therapy has evolved fromWHO Option A in 2010, to Option B in 2013 and Option B+ in 2015, with daily infant nevirapine prophylaxis for at least 6-weeks duration remaining standard of care since 2010. The impact of antiretroviral prophylaxis on infant viraemia and the clinical implications thereof are unclear. We describe confirmatory viral load results within South Africa’s early infant diagnosis program from 2010–2015. Methods: HIV PCR and viral load test data from 2010–2015 were extracted from the South African National Health Laboratory Service’s central data repository of all registered test-sets within the public health sector. HIV PCR and viral load results were linked by a patient linking-algorithm using probabilistic matching of patient demographics. All infants with a positive HIV PCR result and a subsequent HIV viral load result taken ≤6months of age were included. Simple linear regression and logistic regression were used to describe viral load trends. Results: Amongst 5602 infants, 5386 (96.0%) had a quantified baseline viral load result and 216 (4.0%) had a result less than the quantifiable limit of the assay used (lower limit of quantification ranged from 20 to 150 RNA cps/ml). Median age at first PCR was 49 days (IQR: 43-81) and at baseline viral load was 88 days (IQR: 66-116). The median baseline viral load between 2010 and 2015 decreased from 6.3 Log10 (IQR: 5.7-6.8) to 5.8 Log10 (IQR: 4.8-6.4) (p<0.001), with the proportion of infants who had a baseline viral load <4 Log10 increasing from 1.9% to 34.6% (p<0.001). Adjusting for year of PCR testing, younger age at testing was associated with a lower viral load result, regression coefficient 0.09 [95% CI 0.07-0.12; p<0.001]. Amongst 155 infants with a less than quantifiable baseline viral load who had follow up testing there were 77 (49.7%) infants who were confirmed as being HIV infected, 69 (89.6%) of whom had their baseline viral load tested at <3months of age. Conclusion: Between 2010–2015, alongside the introduction of improved maternal prophylaxis, younger age and later year of testing were associated with a significantly lower baseline HIV viral load. These results support findings that antiretroviral prophylaxis may be associated with loss of detectability using virological assays amongst some infants, thereby preventing confirmation of HIV infection early in life.

Poster and Themed Discussion Abstracts

795

DETECTION OF INDUCIBLE HIV IN CHILDREN ON ART DESPITE LOW HIV-1 DNA Shalena Naidoo 1 , Michele Sobolewski 2 , Taylor Buckley 2 , Joshua C. Cyktor 2 , Melissa Tosiano 2 , Mary Grace K. Katusiime 3 , Gert U. van Zyl 3 , Mark Cotton 1 , Richard Glashoff 1 , John Mellors 3

CROI 2017 344