Manual contact-tracing is a typical public health response to the outbreak of a contagious disease (CDC 2020, Kahn 2020). It often occurs at the local level, with data sharing with public health authorities at regional and national levels. People who are known to be infected are screened by a contact tracer who questions them about their movements and contacts during a window of time considered relevant to the contagious nature of the disease. Tracers then communicate with the infected person’s contacts to notify them that they have been exposed to the disease and to advise them to take appropriate steps. Data about contacts collected by public health authorities can also be used in deidentified form for analysis and modeling of the spread of the disease and may prove useful in designing appropriate public health responses (Kahn 2020). The balance between privacy rights and the public interest is met by the fact that the person who is providing this information is known to be infected, and their close contacts may be at risk of contracting and spreading the disease.