Let us start thinking about what to do in the event of a global influenza pandemic.

Abstract

New Zealand in a bubble (Illustration by Nicola Marshall, MRINZ). These stringent public health measures were effective in eliminating COVID-19 for prolonged periods of time in New Zealand. Unexpectedly, the measures also prevented an autumn/winter 2020 influenza epidemic (https://doi.org/10.1016/S0140-6736(20)32166-8). It was not possible to determine the relative importance of each of the specific public health measures in preventing the 2020 influenza epidemic. However, the New Zealand experience in 2021 provided some valuable insights into this question. During the autumn/winter of 2021, when a seasonal influenza epidemic would have been expected, there were no positive influenza isolates from New Zealand reported to the WHO (https://doi.org/10.1016/j.puhe.2021.09.013). New Zealand was at ‘alert level 1’ during this period, when the previous public health measures had been markedly scaled back, with the exception of strict border controls and mask wearing in specific situations, which were retained. The border controls severely limited travel into New Zealand, and required those who did enter to isolate for 14 days in an MIQ facility, although for short periods those travelling from Australia were exempt from this MIQ requirement. While recognizing the inherent limitations in the interpretation of such observational data, these findings suggest that strict border controls can prevent seasonal influenza epidemics. Presumably cases of influenza did enter the country, but were contained by the strict MIQ system, and did not spread beyond the quarantine facilities. This case example has a number of important implications. Firstly, it provides an evidence base for the implementation of border restrictions and MIQ systems in the setting of a global influenza pandemic. Secondly, it does raise the issue as to whether many of the other public health measures employed in New Zealand may not be required in the setting of a global influenza pandemic, at least for prolonged periods. This is an important consideration, as many of the ancillary measures such as school and work closures have profound adverse effects on the community. Let us start thinking about what to do in the event of a global influenza pandemic. We have a portfolio of public health measures that have been used during the COVID-19 pandemic that might be rapidly implemented. Of the potential measures, strict border controls including managed quarantine, together with face mask wearing, are likely to represent the key preventive measures. None declared.