COVID-19 outbreaks in Aotearoa New Zealand: urgent action is required to address systematic causes and consequences of border failures.

Between August and November 2020, Aotearoa New Zealand experienced eight known failures of the COVID-19 border control system. Multiple introductions of this highly transmissible virus into New Zealand's almost completely susceptible population present a high risk of uncontrollable spread, threatening New Zealand's elimination strategy. In this editorial, we propose that, although steps are being taken reactively in response to these known breaches, systematic underestimation of risk across the pandemic response makes future failures inevitable. We present an epidemiological framework for identifying and addressing risk, giving examples of actions that can be taken to reduce the probability of further outbreaks and enable New Zealand to benefit from sustained elimination of COVID-19.