Symptoms of post-traumatic stress and associations with sexual behaviour and PrEP preferences among young people in South Africa, Uganda and Zimbabwe.

BACKGROUND: It is not known whether post-traumatic stress disorder (PTSD) increases HIV-risk behaviours among young people in sub-Saharan Africa. We assessed associations of PTSD symptoms with sexual behaviour, HIV risk perception, and attitudes towards PrEP among young people taking part in the CHAPS community survey. We hypothesised that PTSD symptoms would increase sexual behaviours associated with HIV risk, hinder PrEP uptake and influence preference for daily versus on-demand PrEP. METHODS: Young people without HIV, aged 13-24 years, were purposively recruited in Johannesburg and Cape Town in South Africa, Wakiso in Uganda, and Chitungwiza in Zimbabwe, and surveyed on socio-demographic characteristics, PrEP knowledge and attitudes, sexual behaviour, HIV perception and salience, and mental health. PTSD symptoms were measured using the Primary Care PTSD Screen for the Diagnostic and Statistical Manual of Mental Disorders 5 (PC-PTSD-5). Logistic and ordinal logistic regression was used to assess associations between PC-PTSD-5 score and socio-demographic characteristics, sexual behaviour, HIV risk perception, PrEP attitudes, and substance use, adjusting for age, sex, setting, depression and anxiety. RESULTS: Of 1330 young people (51% male, median age 19 years), 522 (39%) reported at least one PTSD symptom. There was strong evidence that having a higher PC-PTSD-5 score was associated with reported forced sex (OR 3.18, 95%CI: 2.05-4.93), self-perception as a person who takes risks (OR 1.12, 95%CI: 1.04-1.20), and increased frequency of thinking about risk of HIV acquisition (OR 1.16, 95%CI: 1.08-1.25). PTSD symptoms were not associated with willingness to take PrEP, preference for on-demand versus daily PrEP, or actual HIV risk behaviour such as condomless sex. CONCLUSIONS: Symptoms consistent with probable PTSD were common among young people in South Africa, Uganda and Zimbabwe but did not impact PrEP attitudes or PrEP preferences. Evaluation for PTSD might form part of a general assessment in sexual and reproductive health services in these countries. More work is needed to understand the impact of PTSD on HIV-risk behaviour, forced sex and response to preventive strategies including PrEP.

Predictors of oral pre-exposure prophylaxis (PrEP) uptake among individuals in a HIV vaccine preparedness cohort in Masaka, Uganda.

ABSTRACT: Oral pre-exposure prophylaxis (PrEP) significantly reduces human immunodeficiency virus (HIV) acquisition risk. However, data on predictors of PrEP uptake in sub-Saharan Africa are limited. We assessed predictors of PrEP uptake among HIV-uninfected high risk individuals enrolled in a HIV vaccine preparedness study in Masaka, Uganda.Between July 2018 and October 2020, we recruited adults (18-40 years) from sex work hotspots along the trans-African highway and Lake Victoria fishing communities. We collected baseline data on socio-demographics and PrEP awareness, and provided HIV counselling and testing, information on PrEP, and PrEP referrals at quarterly visits. Urine pregnancy tests (women) and data collection on sexual risk behaviour and PrEP uptake were performed every 6 months. We analysed PrEP uptake among participants who had completed 6 months of follow-up.Of the 588 cohort participants, 362 (62%) were included in this analysis. Of these, 176 (49%) were female, 181 (50%) were aged ≤24 years, 104 (29%) worked in sex work hotspots, 74 (20%) were fisher folk. Only 75 (21%) participants initiated PrEP. Predictors of PrEP uptake included having ≥6 sex partners (adjusted odds ratio [aOR] = 2.29; 95% confidence interval [CI] 1.26-4.17), engaging in transactional sex (aOR = 2.23; 95% CI 0.95-5.20), and residence in a nonfishing community (aOR = 2.40; 95% CI 1.14-5.08). The commonest reasons for not starting PrEP were pill burden (38%) and needing more time to decide (27%).PrEP uptake was low and associated with HIV risk indicators in this cohort. Interventions are needed to improve access to PrEP especially in fishing communities.

The effect of current Schistosoma mansoni infection on the immunogenicity of a candidate TB vaccine, MVA85A, in BCG-vaccinated adolescents: An open-label trial.

INTRODUCTION: Helminth infection may affect vaccine immunogenicity and efficacy. Adolescents, a target population for tuberculosis booster vaccines, often have a high helminth burden. We investigated effects of Schistosoma mansoni (Sm) on the immunogenicity and safety of MVA85A, a model candidate tuberculosis vaccine, in BCG-vaccinated Ugandan adolescents. METHODS: In this phase II open label trial we enrolled 36 healthy, previously BCG-vaccinated adolescents, 18 with no helminth infection detected, 18 with Sm only. The primary outcome was immunogenicity measured by Ag85A-specific interferon gamma ELISpot assay. Tuberculosis and schistosome-specific responses were also assessed by whole-blood stimulation and multiplex cytokine assay, and by antibody ELISAs. RESULTS: Ag85A-specific cellular responses increased significantly following immunisation but with no differences between the two groups. Sm infection was associated with higher pre-immunisation Ag85A-specific IgG4 but with no change in antibody levels following immunisation. There were no serious adverse events. Most reactogenicity events were of mild or moderate severity and resolved quickly. CONCLUSIONS: The significant Ag85A-specific T cell responses and lack of difference between Sm-infected and uninfected participants is encouraging for tuberculosis vaccine development. The implications of pre-existing Ag85A-specific IgG4 antibodies for protective immunity against tuberculosis among those infected with Sm are not known. MVA85A was safe in this population. TRIAL REGISTRATION: ClinicalTrials.gov NCT02178748.