COVID-19 alert level systems—Lessons learnt for future public health emergencies: A qualitative study
Hana Rohan, Aaron F. Bochner, Lauren Brown, Elizabeth M. Ortiz, Amanda McClelland
Abstract
During the COVID-19 pandemic, Alert Level Systems (ALS) were widely implemented as public health tools to communicate risk levels and recommend public health and social measures (PHSMs). However, the efficacy of ALS in mitigating disease spread and their impact on public health responses have not been systematically evaluated.
Introduction
During public health emergencies, it is typically necessary to communicate to the public changing levels of risk, along with recommended public health and social measures (PHSMs) to mitigate these risks. Alert Level Systems (ALS) are an emergency preparedness and response tool.
Materials and methods
Data collection consisted of key informant interviews with senior technical staff involved with the design or implementation of ALS in their jurisdictions. Case study jurisdictions were identified using a purposive approach utilising a review of the peer-reviewed and grey literature as well as the research team’s existing knowledge and networks.
Results
Overall, key informants perceived ALS to be useful tools for public communication of risks, due to their simplicity and ease of interpretation, the way they facilitated a perception of response transparency, and their perceived contribution to supporting epidemic control efforts.
Discussion
Our results show that ALS were perceived to be useful public communication platforms during the COVID-19 pandemic. Respondents described how ALS, when accompanied by PHSMs, were believed to improve risk awareness and adherence. These findings reflect stakeholder perceptions of communication and implementation effectiveness rather than formal evaluations of epidemiological impact
Conclusion
Our findings, based on key informant perceptions rather than formal outcome evaluations, suggest that ALS have the potential to serve as useful public communication tools in future epidemics. The ability of ALS to streamline and simplify public communication around risk and the need for PHSMs may support future public health responses.
Citation: Rohan H, Bochner AF, Brown L, Ortiz EM, McClelland A (2026) COVID-19 alert level systems—Lessons learnt for future public health emergencies: A qualitative study. PLoS One 21(6): e0351209. https://doi.org/10.1371/journal.pone.0351209
Editor: Yves Saint James Aquino, University of Wollongong, AUSTRALIA
Received: September 9, 2025; Accepted: May 24, 2026; Published: June 18, 2026
Copyright: © 2026 Rohan et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: This study is based on qualitative key informant interviews conducted with senior public health officials and policymakers across multiple jurisdictions. The interview transcripts contain potentially identifying information, including contextual details about institutional decision-making processes and governance structures. Given the relatively small number of jurisdictions involved and the seniority of participants, full de-identification would not eliminate the risk of deductive disclosure. During the consent process, participants were assured that transcripts would remain confidential and would not be publicly shared. These restrictions were reviewed and approved by the Resolve to Save Lives Research Committee as part of the study’s ethical oversight. For these ethical reasons, the full transcripts cannot be made publicly available or shared. De-identified excerpts supporting the findings are included within the paper and supplementary materials.
Funding: This work was supported by external funding from #startsmall Foundation and the Bill & Melinda Gates Foundation (grant number INV-048317), and internally by Resolve to Save Lives. There was no additional external funding received for this study. The conclusions and opinions expressed in this work are those of the author(s) alone and shall not be attributed to the Gates Foundation. Under the grant conditions of the Gates Foundation, a Creative Commons Attribution 4.0 License has already been assigned to the Author Accepted Manuscript version that might arise from this submission. The external funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: None declared.
