Optimal COVID-19 quarantine and testing strategies

Area of Science:

• Epidemiology
• Mathematical Modeling
• Public Health Policy

Background:

• The COVID-19 pandemic necessitates effective strategies balancing public health with economic and operational needs.
• Current 14-day quarantine recommendations present significant challenges, prompting research into shorter, equally effective alternatives.

Approach:

• Developed a mathematical model to assess post-quarantine transmission probability based on quarantine duration and molecular testing timing.
• Analyzed three quarantine entry scenarios: travel, traced contacts with unknown exposure time, and cases with known exposure time.
• Validated model principles using real-world data from 4,040 SARS-CoV-2 RT-PCR tests on offshore oil rig employees.

Key Points:

• Testing on quarantine exit (or entry and exit) can reduce quarantine duration by 50% with a one-day test result delay.
• Exit testing is more effective at reducing post-quarantine transmission than entry testing.
• Optimal testing for shorter quarantines (up to seven days) occurs on exit.

Conclusions:

• Real-world data confirmed that exit testing identified 16 positive cases among initially negative individuals, preventing expected transmission events.
• Appropriately timed testing enhances the effectiveness of shorter quarantine periods.
• Optimized testing strategies minimize economic impact, operational disruption, and public health risks associated with COVID-19.