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Published on: April 9, 2021
Using a real-world network to model localized COVID-19 control strategies
Josh A Firth1,2, Joel Hellewell3, Petra Klepac3,4
1Department of Zoology, University of Oxford, Oxford, UK.
Contact tracing for COVID-19 is more effective when tracing contacts of contacts. Combining physical distancing with tracing strategies can control epidemics while minimizing quarantines.
Area of Science:
- Epidemiology
- Network Science
- Public Health
Background:
- Case isolation and contact tracing are key strategies for controlling COVID-19 outbreaks.
- The influence of real-world social networks on the effectiveness of these control measures is not fully understood.
Purpose of the Study:
- To simulate SARS-CoV-2 transmission control strategies within a real-world social network.
- To evaluate the impact of different contact tracing approaches and quarantine strategies on outbreak size and efficiency.
Main Methods:
- Utilized high-resolution GPS data from a citizen-science experiment to construct a real-world social network.
- Simulated various control strategies, including contact tracing, tracing of contacts of contacts, and testing/release from quarantine.
- Assessed the effectiveness of strategies based on outbreak size and the proportion of the population quarantined.
Main Results:
- Tracing contacts of contacts significantly reduced simulated outbreak size compared to tracing only contacts.
- Tracing contacts of contacts led to a substantial proportion of the population being quarantined.
- Testing and releasing non-infectious individuals from quarantine paradoxically increased outbreak size.
- Combining physical distancing with contact tracing showed potential for epidemic control with fewer quarantined individuals.
Conclusions:
- Contact tracing and quarantine can function as a 'local lockdown' during periods of high contact rates.
- Targeted tracing and quarantine strategies are most efficient when integrated with complementary measures like physical distancing.
- Understanding social network structures is crucial for optimizing infectious disease control strategies.
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