Many countries are not on track to meet the UNAIDS target of ending HIV as a public health
threat by 2030. One manner in which progress towards such targets to reduce new HIV infection
can be accelerated is through improved use of HIV prevention methods. The HIV Prevention
Cascade framework can be used as a way of identifying the levels of primary prevention method
use and barriers to use among adolescent girls and young women – a target group for increasing
HIV prevention method use - and their potential male partners. The overarching aim of this
thesis was to use the HIV prevention cascade framework to measure levels of prevention method
use, as well as barriers to prevention method use among adolescent girls and young women and
their male partners. Analysis of risk factors associated with HIV acquisition identified some
sexual risk behaviours consistently associated with acquisition of HIV infection, including selfreporting
a non-regular or concurrent sexual partners. Evaluation of a risk differentiation tool
to predict combined HIV/HSV-2 acquisition gave good sensitivity among those already sexually
active and reporting a non-regular partner was predictive of HIV/HSV-2 acquisition. However,
rapid change in sexual risk behaviour was observed across 12 months of follow up and over half
of new infections occurred in those not reporting to have started sex at baseline. Validation of
the HIV prevention cascade framework demonstrated that it was feasible to populate the HIV
prevention cascade framework, including both the main and sub bars, using data collected as
part of the Manicaland Pilot HIV Prevention Cascades Study. Analysis using the HIV prevention
cascade framework found that male condoms were the most commonly used prevention
method and PrEP was the least. Barriers to prevention method use were identified using the
HIV prevention cascade framework, which indicate potential targets for interventions to improve
prevention method use. Barriers were identified for all prevention methods and at each
step of the prevention cascade, indicating the need for multi-level interventions which target
individual, provider, community and structural factors.