Reaching the First 90: Examining Accuracy and Acceptability of an Oral Fluid HIV Test in Children in Harare, Zimbabwe

Background: In 2016, 36.7 million people globally were living with HIV and approximately 70% knew their status. Novel HIV testing methods and strategies are needed to reach the first “90-90-90” target by 2020; that is 90% of people living with HIV know their status. Children and adolescents face additional barriers to HIV testing that stem from gaps in provider-initiated testing and counselling (PITC), parents’ concerns related to stigma and discrimination, and beliefs that children living with HIV cannot survive to adolescence. PITC barriers and the stigma and discrimination parents’ may face when seeking HIV testing and counselling (HTC) for their children could be reduced through a novel HIV testing strategy, which includes oral fluid tests (OFTs) and parents performing oral fluid HIV self-tests (O-HIVST) on their children. Therefore, the study aims of this thesis were: 1) to determine the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of an OFT for HIV in children aged 2-18 using the standard point of care rapid diagnostic test (RDT) as a reference, 2) to explore parents’/guardians’ and older adolescent’s knowledge of, and attitudes about, OFTs and O-HIVST, 3) to explore parents’/guardians’ and older adolescent’s preferences when undergoing O-HIVST. No studies to our knowledge have examined the diagnostic accuracy of OFTs in children or the facilitators of O-HIVST performed by a parent or guardian on their children.

Methods: We conducted the study in two large urban hospitals in Harare, Zimbabwe. The sample included children and adolescents aged 2-18 whose HIV status was unknown. We performed an OFT, followed by a finger-prick RDT to validate the OFT results. In addition, we conducted in-depth interviews (IDIs) with parents/guardians of children aged 2-15 and older adolescents aged 16-18. Quantitative analysis included tabulating descriptive statistics and calculating sensitivity, specificity, PPV, and NPV of the OraQuick ADVANCE® Rapid HIV-1/2 Antibody Test. Thematic qualitative analysis was conducted on the IDIs.

Results: Preliminary sensitivity results of the OFT showed high sensitivity at 100% (95% CI 83.89, 100.00) and high specificity at 99.77% (95% CI 99.17, 99.97) compared to the finger-prick RDT. In addition, PPV was 91.30% (95% CI 71.96, 98.93), and NPV was 100% (95% CI 99.57, 100.00). Qualitative findings showed low knowledge of OFTs and O-HIVST among parents and adolescents. However, participants reported favorable attitudes towards performing O-HIVST on themselves and their children and also reported a preference for a wide range of uptake mechanisms when asked about O-HIVST. Participants expressed concern about O-HIVST but felt that counselling could reduce unfavorable reactions to positive O-HIVST results.

Conclusions: The preliminary analysis confirmed the OFT has high sensitivity, but a larger sample size is needed to obtain a more accurate estimate of OFT sensitivity. If future findings confirm our preliminary results, we recommend OFTs as a method to increase HIV testing and uptake among children. Participants’ low knowledge of OFTs and O-HIVST indicate sensitization is needed before scale up of this new method. We also recommend O-HIVST implementation include a variety of strategies to increase O-HIVST uptake among children and adolescents who may face barriers to traditional HTC.