A Green Zone Strategy for Ireland
Chen Shen∗ , Gerry F Killeen† , Anthony Staines‡ , Yaneer Bar-Yam∗
†University College Cork, Ireland,
‡Dublin City University, Ireland
∗New England Complex Systems Institute, USA
August 11, 2020
Fig. 1. County status in Ireland including five levels of zone distinction, by number of cases in the past 14 days, on July 12, 2020. Three counties have no cases in the last 14 days but don’t qualify for green zone status because of neighboring red zones, i.e. they are yellow zones.
A Green Zone strategy, one that selectively imposes restrictions within a country, e.g. at county level, is the optimal strategy to rapidly reduce the number of COVID-19 cases and accelerate the return to normal social, health, education, and business activity—as each county, province or state becomes clear—without disease and loss of life.
This approach has already been used effectively, but often not completely, in multiple countries, including Ireland, New Zealand, China, Switzerland, and Argentina. Many European countries are now applying Green Zone style approaches, both to allow for response to localized outbreaks and for selective easing of restrictions on travel to neighbouring countries with similar or lower disease rates. Countries that imposed restrictions on non-essential travel, both internationally and between localities within their borders, have achieved very rapid contraction of their epidemics and local, or even national, elimination of the disease. This enabled them to reopen economic activity in most of the affected area within a few weeks, while the most stringent control measures were selectively maintained only in areas with ongoing community transmission (Red Zones).
Right now, Ireland can achieve safety, with consistently normal local activity in many counties, with perhaps the occasional need for more intensive local responses to local outbreaks. To do this, a key policy is a more consistent Green Zone strategy, using international and inter-county travel restrictions to prevent and control larger outbreaks. This will serve as a foundation for a return to comparatively normal domestic economic activities and social life. Partnering with other Green Zone countries will enable international travel, fostering a broader effort to get to zero.