Optimal COVID-19 quarantine and testing strategies

Area of Science:

• Epidemiology
• Mathematical Modeling
• Public Health

Background:

• The 14-day quarantine period for COVID-19 was established to minimize transmission risk.
• There is a need to evaluate shorter quarantine durations combined with testing strategies for feasibility and effectiveness.
• Understanding the probability of post-quarantine transmission is crucial for optimizing public health interventions.

Purpose of the Study:

• To develop a mathematical model quantifying post-quarantine transmission probability.
• To assess the effectiveness of incorporating testing into various quarantine scenarios (travel, contact tracing, known exposure).
• To determine if shorter quarantine periods can be as effective as the standard 14-day quarantine with judicious testing.

Main Methods:

• Development of a mathematical model to calculate the probability of transmission after quarantine.
• Incorporation of testing strategies (entry, exit, or both) into the quarantine model.
• Application and validation of the model using real-world data from offshore oil rig employees.

Main Results:

• Testing on exit, or both entry and exit, can reduce a 14-day quarantine duration by 50%.
• Testing solely on entry shortens quarantine by a maximum of one day.
• A real-world application identified 47 positive cases (16 initially negative) and prevented an estimated nine transmission events among offshore oil rig workers.

Conclusions:

• Judiciously timed testing, particularly on exit, can significantly shorten quarantine periods while maintaining effectiveness.
• Mathematical modeling provides a robust framework for evaluating quarantine and testing strategies.
• Optimized testing protocols can enhance the practicality and efficiency of infectious disease control measures.