Quantifying SARS-CoV-2 transmission suggests epidemic control with digital contact tracing | Science

April 15, 2020

https://science.sciencemag.org/content/early/2020/03/30/science.abb6936

Great idea for #covid19… However, digital contact tracing has serious #privacy issues that have to be considered and perhaps ameliorated.

Quantifying SARS-CoV-2 transmission suggests epidemic control with digital contact tracing

Luca Ferretti1,*, Chris Wymant1,*, Michelle Kendall1, Lele Zhao1, Anel Nurtay1, Lucie Abeler-Dörner1, Michael Parker2, David Bonsall1,3,†, Christophe Fraser1,4,†,‡

Science 31 Mar 2020: eabb6936
DOI: 10.1126/science.abb6936

Fig 2 shows the breakdown of infections into four types:
pre-symptomatic, symptomatic, environmental, and asymptomatic, and they contribute 0.9, 0.8., 0.2, and 0.1 each to the basic reproduction number of 2. To stop the spread of infections, you need to take measures to get the area under the curve to below 1. The paper then shows that when you do quarantining and contact tracing, you can’t get the reproduction number below 1. However, if you improve the speed of quarantining and contact tracing with a digital app/centralized system, then you can get it below 1.