Lift COVID restrictions with great care, as the effects may not be seen for months

CARE should be taken to avoid lifting COVID-19 policy restrictions within short time periods, as it could take more than 2 months to detect the consequences of any changes, according to the authors of modeling research published online today by the Medical Journal of Australia.

Dr Nick Scott from the Burnet Institute and colleagues simulated network-based transmission risks in households, schools, workplaces, and a variety of community spaces (e.g. public transport, parks, bars, cafes/restaurants) and activities (e.g. community or professional sports, large events).

Their modeling told them that policy changes leading to the gathering of large, unstructured groups with unknown individuals (e.g. bars opening, increased public transport use) posed the greatest risk of epidemic rebound, while policy changes leading to smaller, structured gatherings with known individuals (e.g. small social gatherings) posed least risk of epidemic rebound. In the model, epidemic rebound following some policy changes took more than two months to occur.

"Sequential COVID-19 restrictions should not be lifted within short periods," Scott and colleagues concluded.

"Working from home should continue, to minimize public transport use. Additional physical distancing policies are required to mitigate the risks of opening pubs/bars. In settings with low community transmission, care should be taken to avoid introducing multiple policy changes within short time periods, as it could take greater that two months to detect the consequences of any changes. Governments should be particularly wary of lifting restrictions that facilitate a larger number of contacts between people who do not know each other; instead favoring relaxing restrictions to allow smaller gatherings with known contacts."