We use an individual-level transmission and contact simulation
model to explore the effectiveness and resource requirements of
various test-trace-isolate (TTI) strategies for reducing the spread
of SARS-CoV-2 in the UK, in the context of different scenarios
with varying levels of stringency of non-pharmaceutical
interventions. Based on modelling results, we show that selfisolation
of symptomatic individuals and quarantine of their
household contacts has a substantial impact on the number of
new infections generated by each primary case. We further
show that adding contact tracing of non-household contacts of
confirmed cases to this broader package of interventions
reduces the number of new infections otherwise generated by
5–15%. We also explore impact of key factors, such as tracing
application adoption and testing delay, on overall effectiveness
of TTI