Consistent with previous modelling studies and country-specific COVID-19 responses
to date, our analysis estimated that a high proportion of cases would need to self-isolate
and a high proportion of their contacts to be successfully traced to ensure an effective
reproduction number lower than 1 in the absence of other measures. If combined with
moderate physical distancing measures, self-isolation and contact tracing would be
more likely to achieve control of severe acute respiratory syndrome coronavirus 2
transmission.
Source: www.thelancet.com