Skip to main navigation menu Skip to main content Skip to site footer

Original article

Vol. 150 No. 5153 (2020)

Early evidence of effectiveness of digital contact tracing for SARS-CoV-2 in Switzerland

DOI
https://doi.org/10.4414/smw.2020.20457
Cite this as:
Swiss Med Wkly. 2020;150:w20457
Published
16.12.2020

Abstract

In the wake of the pandemic of coronavirus disease 2019 (COVID-19), contact tracing has become a key element of strategies to control the spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Given the rapid and intense spread of SARS-CoV-2, digital contact tracing has emerged as a potential complementary tool to support containment and mitigation efforts. Early modelling studies highlighted the potential of digital contact tracing to break transmission chains, and Google and Apple subsequently developed the Exposure Notification (EN) framework, making it available to the vast majority of smartphones. A growing number of governments have launched or announced EN-based contact tracing apps, but their effectiveness remains unknown. Here, we report early findings of the digital contact tracing app deployment in Switzerland. We demonstrate proof-of-principle that digital contact tracing reaches exposed contacts, who then test positive for SARS-CoV-2. This indicates that digital contact tracing is an effective complementary tool for controlling the spread of SARS-CoV-2. Continued technical improvement and international compatibility can further increase the efficacy, particularly also across country borders.

References

  1. World Health Organization. Coronavirus disease (COVID-19) - Weekly Epidemiological Update. [Cited 2020 Sep 4]. Available from: https://www.who.int/docs/default-source/coronaviruse/situation-reports/20200831-weekly-epi-update-3.pdf?sfvrsn=d7032a2a_4
  2. Salathé M, Althaus CL, Neher R, Stringhini S, Hodcroft E, Fellay J, et al. COVID-19 epidemic in Switzerland: on the importance of testing, contact tracing and isolation. Swiss Med Wkly. 2020;150:w20225.https://doi.org/10.4414/smw.2020.20225
  3. Aleta A, Martín-Corral D, Piontti APY, Ajelli M, Litvinova M, Chinazzi M, et al. Modeling the impact of social distancing, testing, contact tracing and household quarantine on second-wave scenarios of the COVID-19 epidemic. medRxiv. 2020;2020.05.06.20092841.
  4. Kucharski AJ, Klepac P, Conlan AJK, Kissler SM, Tang ML, Fry H, et al.; CMMID COVID-19 working group. Effectiveness of isolation, testing, contact tracing, and physical distancing on reducing transmission of SARS-CoV-2 in different settings: a mathematical modelling study. Lancet Infect Dis. 2020;20(10):1151–60.https://doi.org/10.1016/S1473-3099(20)30457-6
  5. Ferretti L, Wymant C, Kendall M, Zhao L, Nurtay A, Abeler-Dörner L, et al. Quantifying SARS-CoV-2 transmission suggests epidemic control with digital contact tracing. Science. 2020;368(6491):eabb6936.https://doi.org/10.1126/science.abb6936
  6. Troncoso C, Payer M, Hubaux J-P, Salathé M, Larus J, Bugnion E, et al. Decentralized Privacy-Preserving Proximity Tracing. arxiv. 2020. Available from: https://arxiv.org/abs/2005.12273
  7. von Wyl V, Bonhoeffer S, Bugnion E, Puhan MA, Salathé M, Stadler T, et al. A research agenda for digital proximity tracing apps. Swiss Med Wkly. 2020;150:w20324. doi:.https://doi.org/10.4414/smw.2020.20324
  8. World Health Organization. Ethical considerations to guide the use of digital proximity tracking technologies for COVID-19 contact tracing. [Cited 2020 Sep 4]. Available from: https://www.who.int/publications/i/item/WHO-2019-nCoV-Ethics_Contact_tracing_apps-2020.1
  9. Gasser U, Ienca M, Scheibner J, Sleigh J, Vayena E. Digital tools against COVID-19: taxonomy, ethical challenges, and navigation aid. Lancet Digit Health. 2020;2(8):e425–34.https://doi.org/10.1016/S2589-7500(20)30137-0
  10. Telecommunication SFO of ITS and. SwissCovid Exposure Score Calculation. [Cited 2020 Sep 4]. Available from: https://github.com/admin-ch/PT-System-Documents/blob/master/SwissCovid-ExposureScore.pdf
  11. World Health Organization. Contact tracing in the context of COVID-19. [Cited 2020 Sep 4]. Available from: https://www.who.int/publications/i/item/contact-tracing-in-the-context-of-covid-19
  12. von Wyl V, Hoeglinger M, Sieber C, Kaufmann M, Moser A, Serra-Burriel M, et al. Are COVID-19 proximity tracing apps working under real-world conditions? Indicator development and assessment of drivers for app (non-)use. medRxiv. 2020. doi:https://doi.org/10.1101/2020.08.29.20184382
  13. Swiss Federal Office of Statistics. Calculation methods for estimating the number of active SwissCovid apps. [Cited 2020 Sep 4]. Available from: https://www.experimental.bfs.admin.ch/bfsstatic/dam/assets/13667538/master
  14. Swiss Federal Office of Statistics. SwissCovid App Monitoring. [Cited 2020 Sep 4]. Available from: https://www.experimental.bfs.admin.ch/expstat/en/home/innovative-methods/swisscovid-app-monitoring.html
  15. Corona Immunitas. [Cited 2020 Sep 4]. Available from: https://www.corona-immunitas.ch
  16. West EA, Anker D, Amati R, Richard A, Wisniak A, Butty A, et al.; Corona Immunitas Research Group. Corona Immunitas: study protocol of a nationwide program of SARS-CoV-2 seroprevalence and seroepidemiologic studies in Switzerland. Int J Public Health. 2020;65(9):1529–48.https://doi.org/10.1016/S0140-6736(20)31304-0
  17. Zurich Coronavirus Cohort: an observational study to determine long-term clinical outcomes and immune responses after coronavirus infection (COVID-19), assess the influence of virus genetics, and examine the spread of the coronavirus in the population of the Canton of Zurich, Switzerland. [Cited 2020 Sep 4]. Available from: http://www.isrctn.com/ISRCTN14990068
  18. White IR, Royston P, Wood AM. Multiple imputation using chained equations: Issues and guidance for practice. Stat Med. 2011;30(4):377–99.https://doi.org/10.1002/sim.4067
  19. Cheng H-Y, Jian S-W, Liu D-P, Ng T-C, Huang W-T, Lin H-H ; Taiwan COVID-19 Outbreak Investigation Team. Contact Tracing Assessment of COVID-19 Transmission Dynamics in Taiwan and Risk at Different Exposure Periods Before and After Symptom Onset. JAMA Intern Med. 2020;180(9):1156–63.https://doi.org/10.1001/jamainternmed.2020.2020
  20. Park YJ, Choe YJ, Park O, Park SY, Kim Y-M, Kim J, et al.; COVID-19 National Emergency Response Center, Epidemiology and Case Management Team. Contact Tracing during Coronavirus Disease Outbreak, South Korea, 2020. Emerg Infect Dis. 2020;26(10):2465–8.https://doi.org/10.3201/eid2610.201315
  21. Abueg M, Hinch R, Wu N, Liu L, Probert WJM, Wu A, et al. Modeling the combined effect of digital exposure notification and non-pharmaceutical interventions on the COVID-19 epidemic in Washington state. medRxiv. 2020. doi:https://doi.org/10.1101/2020.08.29.20184135

Most read articles by the same author(s)

1 2 3 > >>