  As we enter the control phase of the COVID-19 pandemic, many efforts have
been dedicated to developing smartphone-based contact tracing apps in order to
automatically identify people that a person with COVID-19 might have infected.
These applications while potentially useful, present significant adoption,
societal, technical and privacy challenges.
  We propose ACDC-Tracing, a simpler, anonymous, voucher-based contact tracing
solution that relies on peoples' knowledge of their own close contacts. People
who test positive are given an anonymous voucher which they can share with a
limited number of people whom they think they might be infected. The recipients
can use this voucher to book a COVID-19 test and can receive their test results
without ever revealing their identity. People receiving positive result are
given vouchers to further backtrack the path of infection.
  This is a fully anonymous solution which does not require any sharing of
location data, Bluetooth, or having an app installed on people's mobile device.
Moreover, ACDC-Tracing can be tested for effectiveness at a small scale without
requiring adoption by the entire population, which would enable acquiring fast
evidence about its efficacy and scalability. Finally, it is compatible with and
complementary to alternative approaches to contact tracing.
