CROI 2020 Abstract eBook

Abstract eBook

Poster Abstracts

Our objective was to evaluate trends over time in marijuana, alcohol, and opioid use during pregnancy and the first year postpartum among US WLHIV. Methods: We analyzed data on marijuana, alcohol, and/or opioid use from the Surveillance Monitoring for ART Toxicities (SMARTT) study of the Pediatric HIV/AIDS Cohort Study. SMARTT has been enrolling pregnant WLHIV at 22 US sites since 2007. SMARTT-enrolled pregnant WLHIV from 2007-2019 with self-reported substance use data available in pregnancy, 1 year postpartum, or both were included (postpartum opioid use not collected). Prevalence of any marijuana, alcohol, opioid, and concomitant alcohol and marijuana use was calculated by calendar year, separately for pregnancy and postpartum periods. We fit log binomial general estimating equation models to evaluate linear trend in use over time, accounting for repeat pregnancies. Results: Substance use data were available for 2,926 pregnancies from 2,310 WLHIV. Women were primarily non-Hispanic black (63.5%) or Hispanic (28.1%) and aged 25-39 years (67.6%). Between 2007 and 2019, marijuana use during pregnancy increased from 7.1% to 11.7% (Figure 1a). Alcohol and opioid use in pregnancy were unchanged over this period (mean prevalence 9.4% and 5.2% respectively). Alcohol and marijuana use were more prevalent in the 1st trimester compared to the 2nd or 3rd, while opioid use was similar across trimesters. In the postpartum period, alcohol and marijuana use were common (mean prevalence 44.4% and 13.6% respectively), with marijuana increasing over time (Figure 1b). On average, risk of marijuana use increased each year by 6% and 11% for pregnancy and postpartum, respectively (Relative Risk [RR] 1.06, 95% Confidence Interval [CI] 1.03-1.10; RR 1.11, 95% CI 1.06-1.16). Postpartum combined alcohol and marijuana use increased from 6.7% to 16.4%, a 10% per year increase (RR 1.10, 95% CI 1.05-1.15). Conclusion: Opioid use among pregnant and postpartumWLHIV in SMARTT remained low and stable despite the US opioid epidemic, whereas the prevalence of marijuana use increased between 2007 and 2019, as did postpartum concomitant alcohol use. Increasing marijuana use in pregnant and postpartumWLHIV warrants further attention.

1 Duke University, Durham, NC, USA, 2 Duke Human Vaccine Institute, Durham, NC, USA, 3 Los Alamos National Laboratory, Los Alamos, NM, USA Background: HIV-1 can be transmitted from infected mothers to their fetuses during pregnancy. However, the transmission timing, viral diversity, and selection pressure on fetal viruses during pregnancy is poorly understood. A better understanding of transmission mechanisms will be key to further reduce the mother-to-child-transmission (MTCT) rate. Methods: Viral RNA was extracted from plasma of 12 mothers (at birth) and their in utero infected infants (from birth to 3 months after delivery). All infants were HIV-1 positive by detecting HIV-1 DNA genome in infant or cord blood at birth. Multiple env gene sequences were obtained from each sample using single genome amplification (SGA). Genetic diversity, phylogenetic trees, highlighter plots were used to infer transmitted/founder (T/F) viruses in the infants and to study the viral populations in both mothers and infants. Infection time was estimated using the Poisson-Fitter tool. Selection signatures in paired maternal viruses were analyzed using SNAP and amino acid sequence alignments. Results: A total of 846 env gene sequences (317 frommothers and 529 from infants) were obtained. Homogenous viral populations were found in 6 infants and 2 were infected with 2 to 3 T/F viruses. The estimated time of infection for these infants is within 2 months (37-3 days) before delivery. High genetic diversity was found in 4 other infants. The time of infection for these 4 infants could not be reliably estimated by current computational analysis tools, possibly due to extensive recombination in the samples. The high genetic diversities strongly suggest that the fetuses were infected in early pregnancy. SNAP and amino acid sequence analysis showed that C1, V1 and V5 regions in the infant Env sequences were highly variable. Some of these signatures in infant viruses were distinct frommother, indicating that placentally-transmitted viruses were under strong selection pressure in fetuses. Higher IgG-mediated neutralization potency was found in some placental plasma compared to that of peripheral plasma from the same mother, suggesting possible selection of HIV-neutralizing IgG subpopulations for placental transfer. Conclusion: The majority of in uterus transmissions occur in the late third trimester during pregnancy, possibly due to the thinning placenta membrane. The variable regions in the infant env sequences suggest that immune system in fetuses is able to exert strong selection pressure on fetal viral population. 782 MATERNAL RISK STRATIFICATION TO IDENTIFY HIGH-RISK INFANTS FOR HIV BIRTH TESTING Haurovi Mafaune 1 , Emma Sacks 1 , Addmore Chadambuka 1 , Emmanuel Tachiwenyika 1 , Francis Simmonds 1 , Reuben Musarandega 1 , Tichaona Nyamundaya 1 , Jennifer Cohn 1 , Agnes Mahomva 2 , Angela Mushavi 1 1 Elizabeth Glaser Pediatric AIDS Foundation, Washington, DC, USA, 2 Zimbabwe Ministry of Health and Child Care, Harare, Zimbabwe Background: In 2017, Zimbabwe adopted a modified version of the World Health Organization 2016 recommendation on HIV birth testing by offering HIV testing at birth only to infants at “high risk” of HIV transmission (criteria based on timing of maternal diagnosis, viral load, and ART adherence). However, there is paucity of evidence on sensitivity, specificity and predictive value for this approach. This study focuses on assessing the sensitivity and specificity of birth testing “high risk” infants only compared to birth testing of all HIV-exposed infants. Methods: This was an analytic cross-sectional study. A five-question maternal risk screening tool based on the national guidelines definition of risk was administered to mothers of all HIV-exposed infants identified within 48 hours of birth at 10 study sites from November 2018 to July 2019. At these sites, a nucleic acid HIV test was performed on all HIV-exposed infants irrespective of risk status. Univariate and bivariate analysis were used to estimate the performance of the risk screening tool. Results: A total of 2,080 infants were enrolled. A nucleic acid test for HIV was successfully performed on 1,970 infants (95%) of whom 266 (13.5%) were classified as high risk infants. HIV prevalence for all infants tested was 1.5% (95% CI: 1%—2%) while prevalence among high risk infants and low risk infants was 6.8% (95%CI: 3.7%—9.8%) and 0.6% (95%CI: 0.3%—1%) respectively. There was a significant association between maternal HIV transmission risk status and HIV infection (p-value <0.001). Sensitivity and specificity of the maternal risk screening tool was at 62.1% (95%CI: 44.4%—79.7%) and 87.2% (95%CI: 85.7%—88.7%), respectively; positive and negative predictive values were 6.8% (95%CI: 3.7%—9.8%) and 99.4% (95%CI: 99.0%—99.7%) respectively Sensitivity and specificity in detecting HIV status

Poster Abstracts

781 TRANSMISSION, VARIATION, AND EVOLUTION OF IN UTERO TRANSMITTED HIV-1

Manukumar Honnayakanahalli Marichannegowda 1 , Michael Mengual 1 , Amit Kumar 2 , Elena E. Giorgi 3 , David R. Martinez 2 , Joshua J.Tu 2 , Xiaojun Li 1 , Sallie Permar 2 , Feng Gao 1

CROI 2020 289