The effect of border controls on the risk of COVID-19 reincursion from international arrivals
Executive Summary
A 14-day period of managed isolation or quarantine (MIQ) with day 3 and day 12 testing reduces the risk of an infectious case being released into the community to a very low level.
A five-day quarantine period is ineffective and would present a much greater risk to the community.
Any mixing of individuals in MIQ that could allow transmission of COVID-19 increases the risk of an infectious case being released into the community.
Strict infection control and use of PPE by staff at MIQ is essential and close contact between individuals in MIQ and staff must be avoided.
Provided the above guidelines are followed, special exemptions restricted to the second week of stay and after an additional negative test result has been returned pose little additional risk.
The ratio of cases detected in the second week to cases detected in the first week can be used to estimate whether transmission within MIQ is occurring, although this requires a larger sample size than is currently available.
