Digital herd immunity and COVID-19

Area of Science:

• Epidemiology
• Public Health
• Digital Health

Background:

• Traditional herd immunity relies on individual immunity within a population.
• The COVID-19 pandemic highlighted the need for innovative epidemic control strategies.

Purpose of the Study:

• To introduce and analyze the concept of 'digital herd immunity' using smartphone technology.
• To investigate the conditions under which digital herd immunity can prevent epidemics.

Main Methods:

• Development of a simple branching-process model for disease transmission.
• Simulation and analysis of epidemic dynamics based on smartphone usage and contact tracing.

Main Results:

• Digital herd immunity is achievable through smartphone-based contact tracing, even with zero individual immunity.
• A phase transition from an immune to an epidemic state occurs as smartphone usage declines.
• The effectiveness of digital immunity is independent of the proportion of non-symptomatic transmission.

Conclusions:

• Smartphone-driven contact tracing can establish population-level immunity ('digital herd immunity').
• Maintaining high smartphone adoption is crucial for sustained epidemic prevention.
• This digital approach offers a novel strategy for managing infectious disease outbreaks.