Halting SARS-CoV-2 by Targeting High-Contact Individuals

TL;DR

This study investigates whether targeting highly connected individuals can effectively halt SARS-CoV-2 transmission, emphasizing the importance of contact variability and network-based interventions.

Contribution

It demonstrates through data analysis and simulations that targeting high-contact individuals significantly improves containment of SARS-CoV-2.

Findings

High-contact individuals are a small fraction of the population.

Average contact duration is consistent regardless of contact frequency.

Targeting hubs enhances containment effectiveness.

Abstract

Network scientists have proposed that infectious diseases involving person-to-person transmission may be effectively halted by targeting interventions at a minority of highly connected individuals. Can this strategy be effective in combating a virus partly transmitted in close-range contact, as many believe SARS-CoV-2 to be? Effectiveness critically depends on high between-person variability in the number of close-range contacts. We analyze population survey data showing that indeed the distribution of close-range contacts across individuals is characterized by a small fraction of individuals reporting very high frequencies. Strikingly, we find that the average duration of contact is mostly invariant in the number of contacts, reinforcing the criticality of hubs. We simulate a population embedded in a network with empirically observed contact frequencies. Simulations show that targeting hubs robustly improves containment.