Projektet har möjliggjorts med bidrag från Nordiska ministerrådet, diarienummer 102960. Projektet etablerade en samlad dokumentation och analys av hur utvecklingen under pandemin fortskridit inom fem viktiga folkhälsoområden i Norden.

Aktiviteter:

1. Projektmöte i Stockholm – under International Association of National Public Health Institutes (IANPHI) årsmöte november 2022
2. Personligt projektmöte i Stockholm 25–26 maj 2025
3. Digitala projektledningsmöten
4. Onlinemöten i de fem projektgrupperna vid behov
5. Grundlig genomgång av dokumentation relaterad till pandemiåtgärder på de fem undersökta områdena.
6. Webbinarier

• Följande har uppnåtts genom projektet
• Slutliga utvärderingsrapporter och/eller vetenskapliga publikationer som innehåller de viktigaste resultaten på fem områden:
• Testning och smittspårning
• Vaccinationsprogram
• Gränsrelaterade frågor
• Bördan av intensivvårdsinläggningar
• Nationella utvärderingar av hanteringen av pandemier.
• Fortsatt samarbete mellan representanter (Nordiska statsepidemiologer) från de nordiska länderna i samband med uppföljning av pandemiåtgärder.
• En bakgrund till utvecklingen av beredskapen inför framtida pandemier.
• En rekommendation om att stödja och formalisera gruppen av nordiska statsepidemiologer.

The activities undertaken have been made possible with grants funded from the Nordic Council of Ministers, reference number 102960. The project established a collected documentation and analysis of how the development during the pandemic progressed in five important public health areas in the Nordic Region.

Activities:

• Project meeting in Stockholm- during the International Association of National Public Health Institutes (IANPHI) Annual Meeting November 2022
• In person project meeting in Stockholm 25-26 May 2025
• Online project management meetings with project-group leaders
• Online meetings in the five project groups as required
• Thorough review of documentation related to the pandemic response in the five areas examined.
• Webinars

• The following has been achieved by the project
• Final assessment reports and/or scientific publications including main findings in five areas:
• Testing and contact tracing
• Vaccination programs
• Border related issues issues
• The burden of intensive care admissions
• National evaluations on handling of pandemic.
• Continued collaboration among representatives (Group of Nordic State Epidemiologists) from the Nordic countries related to follow-up on pandemic response actions.
• A background to the development of preparedness of future pandemics.
• A recommendation to sustain and formalise the Group of Nordic State Epidemiologists.

This report is the result of a collaboration among the Nordic Public Health Institutes (PHI) in following up five different aspects of the COVID-19 pandemic. The work was funded in part by the Nordic Council of Ministers.

The Nordic PHIs have a longstanding tradition in collaboration and forming networks in different areas; not least in communicable disease prevention and control. These collaborative networks made it possible to start and implement a project to collect experiences and analyse available data and information from the pandemic in the Nordic Region.

The report describes how the Nordic countries and to a varying extent the Faroe Islands and Åland managed the pandemic in slightly different ways. As well, the ability scale-up response efforts strategically according to the arising challenges over the pandemic in the Nordic Region is presented. The Nordic PHIs have extensive possibilities to collect and analyse data which provide a collaborative picture what happened during and after the pandemic. With this, the project provided a unique opportunity for documenting experiences that were achieved during the pandemic which are also valuable for the future. The report is an important source of information to update pandemic preparedness plans and when managing the next pandemic.

The project process also provided a possibility for the Nordic PHIs to further deepen and strengthen their ties and understanding of each other. Among the findings, this the report concludes that in order to prepare for the next pandemic, that the Nordic collaboration in these areas continue; noting that this project has facilitated working collaborative together.

The report has been developed by working group with participation of all the Nordic countries and to a varying degree also the Faroe Islands, Greenland and Åland.

Public Health Agency of Sweden

Olivia Wigzell
Director-General

The Public Health Institutes in the Nordic Region have a longstanding tradition of meeting, sharing information and collaboration in joint projects. An informal Group of Nordic State Epidemiologists or equivalent has had collaborative contact for at least the past 25 years. The frequency of contact has varied over the years and has occurred mainly by way of in-person meetings or online. After the establishment of the European Centre for Disease Prevention and Control (ECDC) in 2005, meetings and exchanges took place during the meetings of the ECDC Advisory Forum.

Nordic groups continue to work in thematic public health areas to share developments and experiences. The independent Könberg Report from 2014 suggested 14 measures to strengthen and further developing the Nordic Cooperation over 5-10 years. The measures included the establishment of Nordic Networks on topics such as AMR, reducing inequalities in health and a greater mandate for co-operation within health preparedness. In 2023-2024 the measures were evaluated and among the findings for health preparedness, the importance of informal dialog and a need for strategic focus and prioritisation was underscored.

In the context of health preparedness, the Svalbard Group formally known as the Nordic Public Health Preparedness Group has existed since 2002 and is based on the Nordic Health Preparedness agreement. The purpose of this group is to improve co-operation and to share information, skills, and knowledge across the Nordic Region in the field of public health and social services in relation to emergency preparedness, crisis and disaster management.

Similar to the Svalbard Group, the informal Group of Nordic State Epidemiologists immediately increased the traditional exchange of information during the start of the COVID-19 pandemic. This Group was then enlarged to include others involved in the management of the pandemic to expand the collaboration in the pandemic response areas and facilitate information sharing. The pandemic provided both an opportunity and a challenge in this respect whereby the Group of Nordic State Epidemiologists met regularly throughout the pandemic to exchange information such as epidemiological updates and vaccine strategies. This forum for exchange was deemed by the group as an invaluable source of information to determine what happened in the neighbouring countries as well as to share information about pandemic response measures implemented or planned.

The project Following-up on the COVID-19 pandemic has been led by the Public Health Agency of Sweden together with a project management group composed of the members of the Group of Nordic State Epidemiologists. In addition, analysts from the Public Health Institutes represented contributed to the project work.

Initially the Public Health Institutes in each country worked together in Stockholm in 2022 on the project proposal to follow-up the response measures to the pandemic. During the process to apply for funding from the Nordic Council of Ministers, the Faroe Islands, Åland and Greenland were invited to join; whereby Greenland did not have the capacity to take actively take part and the Faroe Islands’ participation was limited.

The participating Public Health Institutes are:

Denmark Statens Serum Institut (SSI) is a national public health institute under the Danish Ministry of the Interior and Health. SSI is responsible for the prevention and control of infectious diseases and congenital disorders through surveillance, diagnostics, research, and expert advisory services. The institute plays a central role in national health preparedness, including vaccine supply, pandemic response, and biological threat management. As a sector research institute, SSI also conducts internationally recognised research to strengthen public health interventions, diagnostics, and preventive strategies.

Finland The Finnish Institute for Health and Welfare (THL) is an independent state-owned expert and research institute dedicated to promoting the well-being, health, and safety of the population. THL’s primary responsibilities encompass conducting research and providing expert advice to decision-making in order to prevent illnesses and social issues, foster the development of a comprehensive welfare society, and support the social welfare and healthcare systems. Furthermore, THL oversees, facilitates, and enhances national monitoring and surveillance systems for infectious diseases, and actively participates in the national vaccination program. Additionally, when necessary, THL provides support and conducts outbreak investigations, and develops comprehensive national guidelines for the effective control of infectious diseases.

Iceland The Directorate of Health is Iceland’s national public health authority under the Ministry of Health. The Chief Epidemiologist is Head of the Office of Communicable Disease Control and is responsible for nationwide prevention and control of communicable diseases, including immunization programs and outbreak response. The Chief Epidemiologist oversees surveillance systems, maintains communicable disease and antimicrobial use registries, and coordinates with health professionals and national agencies, including Civil Protection. The role also includes international collaboration—particularly with Nordic, European and WHO partners—and extends to preparedness and response for chemical, biological, and radiological or nuclear health threats

Norway The Norwegian Institute of Public Health (NIPH) is a national competence institution placed directly under the Ministry of Health and Care Services. The NIPH is the national infection control institute, with associated functions and responsibilities, including surveillance, epidemic intelligence, national outbreak investigations, advice, and coordination of national vaccination programmes. The NIPH produces, summarizes and disseminates knowledge to support good public health efforts and healthcare services.

Sweden The Public Health Agency ofSweden is a national agency responsible for public health under the Swedish Ministry of Health and Social Affairs. Its main mission is to promote health, prevent illness, and protect against health threatsin the population. Key responsibilities include monitoring and analyzing public health trends, managing infectious disease control and national vaccination programs, supporting health promotion and providing data, research and policy recommendations. During major health crises—such as the COVID-19 pandemic—the agency plays a central role in risk assessment, public communication, andcoordination of national responses.

Åland The Government of Åland’s Health Care Bureau develops, leads and monitors health care services and public health actions on Åland. The Bureau is also responsible for developing health-care legislation, which is Åland capacity as per the Åland Autonomy Act. Moreover, the Bureau is the management authority for parts of the Finnish Communicable Disease Act, including strategic planning and monitoring of pandemic response on the regional level.

During the founding project meeting, Sweden took on the role as project lead. Contact points was designated in each National Public Health Institute (NPI) to form a project management group and collaboration in this structure started.

A simplified Delphi process was established to choose five areas of work and to develop a workplan. The workplan specified that each country would take the responsibility for one area and develop a corresponding plan and report.

The areas and lead countries were as follows:

Testing and contact tracing - Sweden

Vaccination programs - Denmark

Border related issues - Finland

The burden of intensive care admissions - Norway

National evaluations - Iceland

The main goal of the project was to document measures taken, results and lessons learned during the pandemic in the five different areas in the Nordic countries.

Achieving the goal of the project was continually discussed at several meetings, in particular, to determine how far data could be analysed and which conclusions could be drawn. As presented in the reports, the Work Groups had different approaches which were dependent on the availability of data and the complexity of the issues in the area.

The Project Management Group composed of the leaders of each Work Group planned the overall project in the five areas. Methodology and approach to gather and analyse available data in each area were agreed upon. Thereafter, the five Work Groups worked independently to develop and implement plans including methodology for each area. Each Work Group leader nominated persons representing Denmark, Finland, the Faroe Islands, Iceland, Norway, Sweden and Åland in all groups.

The methodology for each of the five areas is available in the summaries below.

The project was an important platform for discussion after the pandemic and highlighted the usefulness and need for communication between the Nordic NPIs in Denmark, Finland, the Faroe Islands, Greenland, Iceland, Norway, Sweden and Åland. Even if there were challenges experienced by several of the PHIs to implement the project, due to reorganisation and cutbacks on resources, the project could deliver on its proposal. Funding from the Nordic Council of Ministers enabled an in-person meeting which proved to be very valuable for discussing the areas in-depth and drawing conclusions of the project.

The main result is a robust description of the response over the pandemic in the five different areas from Denmark, Finland, the Faroe Islands, Iceland, Norway, Sweden and Åland and an in-depth analysis of the burden of intensive care admissions with COVID-19.

The Nordic countries and Åland adopted a variety of strategies for testing and contact tracing. The strategies reflect the different health system structures, public health capacities and governance models as well as a wide variety of reasons for testing. Initially testing capacity was limited with a gradual increase during spring and summer of 2020, at varying rates among the countries and with varying maximum capacity achieved. Contact tracing was most effective during periods of low community transmission. The Nordic experience underlines that large-scale testing and contact tracing are vital components of early pandemic response. Future preparedness should build on these lessons to ensure agile, equitable and cost-effective systems.

The COVID-19 vaccination strategies across the Nordic region shared common objectives but were shaped by national contexts, health system capacities, and evolving epidemiological dynamics. Vaccination programs began in late December 2020 and followed a phased approach. The first phases focused on high-risk groups such as the elderly, individuals with chronic illnesses, and frontline healthcare personnel. As vaccine availability improved, eligibility expanded and strategies adapted to new variants, shifting risk assessments and evidence on vaccine effectiveness. While overarching goals were similar, the operationalization differed among the Nordic Countries. Key lessons include the value of flexibility within a shared strategic framework, the importance of rapid data sharing, and the benefit of close regional cooperation. These findings form a strong foundation for future pandemic preparedness and vaccine planning.

The impact of border restrictions, quarantine, testing, and travel certificates on transmission within the country remains uncertain because assessing the usefulness of the measures is limited due to lack of formal evaluations. In the Nordic Region, several types of border-related measures were implemented at various points during the pandemic to reduce the risk of cross-border transfer of the virus and subsequent domestic transmission from individuals arriving from abroad. The policies, legal basis and implementation of measures differed greatly between countries. There were differences between the broad goals, policies, mitigation measures and implementation timelines. However, discussion of border measures was continuous between Nordic Public Health Institutes and situation awareness was shared regularly. This collaboration was critical to be able to assess, without results from focused evaluations, the observations of possible impacts of each measure.

The study utilized nationwide registry data used for routine surveillance of severe COVID-19 showed that the burden of intensive care unit (ICU) admissions was influenced both by non-modifiable risk factors such as high age and male sex, and by dynamic changes, including the intensity of community transmission, the emergence of new SARS-CoV-2 variants, developments in the care of COVID-19, and increasing immunity in the population following vaccination, infection or both. While the differences between the data sources used by each country and the lack of common case definitions limit the comparability of the data to some extent, assessments like the present study can provide valuable information on the burden of pandemic respiratory infections. Continued high-quality surveillance, research preparedness and further research on the implications of Public Health and Social Measures (PHSMs) for the severity of disease are needed for being better prepared for future pandemics.

Following the COVID-19 pandemic, the governments of the Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden), as well as the governments of Åland and the Faroe Islands, conducted after-action reviews (AARs) and assessments to different degrees. One key lesson learned during the process of compiling these reports is the importance of considering AARs at the beginning of a pandemic. Early planning of AARs would allow for timely discussions on adopting a uniform or standardized approach to documenting lessons learned across the Nordic countries. This would enhance the comparability and readability of AARs and support cross-country learning. We suggest that availability of evaluations in English be encouraged in the future to improve the quality of the work by a peer review process and also to disseminate the important lessons to a broader audience.

The project has shown the great potential the Nordic Public Health Institutes have when they collaborate as a collective group. This collaborative report presents findings that measures to manage the pandemic were grounded on the country context whereby many different aspects played a role. Importantly. the Nordic countries were able to scale up in attempts to meet the needs for surveillance of epidemiological indicators such as intensive care admissions, prompt testing and vaccination. The area of border related issues was inconsistent among the Nordic Countries. The foundation of this collaboration is information sharing which allows for critical discussions, in-depth questions and consensus building to draw conclusions for better preparedness for the Nordic Region. In this project to follow-up the pandemic, this finding is consistent that all Public Health Institutes in each Work Group benefited of collaboration.

The Group of Nordic State Epidemiologists served as an important tool for exchanging information and knowledge throughout the pandemic from the start to the present time including within this project. Moreover, continual collaboration during times when there is not a public health emergency would mutually benefit the National Public Health Institutes of Nordic Region for better preparedness and critical scientific discussions.

Ways to formalise this structure could include timebound project structures or, instilling formal Group of Nordic State Epidemiologists within Public Health Institutes. In this way, Public Health issues such as vaccination strategies, national preparedness planning and strategies for communicable disease prevention and control would have an arena for Nordic collaboration and sustained sharing of experiences.

Collaboration allowed for the analysis and concluding findings of the five Work Groups which serve to inform future preparedness planning. Testing and contact tracing strategies varied over time and between the countries to some extent depended on resources available and the activities undertaken are described in detail in the report. The vaccination strategies evolved over the pandemic and countries independently developed vaccination campaigns according to national structures. Evolving border related measures were implemented over the course of the pandemic. Yet the impact of border restrictions, quarantine, testing, and travel certificates on transmission within the country remains uncertain as formal evaluations of these measures are scarce. The use of data across all of the Nordic Region on intensive care admissions allowed the comparison of the burden of severe COVID-19 on the population in the Nordic countries and autonomous regions, highlighting the impact of factors such as age, sex, immunity, intensity of community transmission and the emergence of new SARS-CoV-2 variants on the burden of severe disease. Finally, the area of Nordic evaluation determined that countries used various approaches to evaluate the pandemic in respective countries and for the future, a framework for a collaborative evaluation could be considered

The initiatives to facilitate research and evaluations during a need to become permanent.

All five areas underscore the importance of evaluation as the Nordic Region as a whole and preparations to facilitate its implementation which is critical during crises but also under normal circumstances.

Work Group Leader: Public Health Agency of Sweden

This executive summary presents key insights from the Nordic countries’ and Åland’s experiences with large-scale testing and contact tracing during the COVID-19 pandemic. The Nordic countries and Åland adopted a variety of strategies for testing and contact tracing combined with isolation of cases and quarantine of contacts. The strategies reflected different health system structures, public health capacities and governance models as well as a wide variety of reasons for testing.

Initially testing capacity was limited with a gradual increase during spring and summer of 2020, at varying rates and with varying maximum capacity achieved among the countries. Early and widespread testing in combination with contact tracing and isolation/quarantine proved to be central to pandemic control and the rapid scaling up of testing and likely limited transmission and reduced need for broader restrictions. Fast turnaround times for testing—often within 24 hours—were critical in enabling timely isolation and contact tracing. In contrast, where delays of several days occurred, opportunities to break transmission chains were often lost.

Contact tracing was most effective during periods of low community transmission. Once incidence increased, especially during the Omicron variant wave, its utility declined sharply due to system overload and delayed responses.
Digital tools played a key role, particularly when integrated with manual processes and national data systems. National real-time IT platforms were implemented to varying degrees among the participating countries, with the support of manual contact tracing and regional systems. The availability and usability of digital infrastructure influenced efficiency and adaptability of test-and-trace operations.

Across the Nordic Region, countries highlighted the importance of adjusting strategies over time. As population immunity increased and new variants emerged, the balance between epidemiological impact and societal cost shifted. Testing and contact tracing remained important, but should have been continuously evaluated in light of effectiveness, feasibility, and proportionality. In addition to isolation of confirmed cases and quarantine of exposed contacts, test results provided surveillance data for identifying risk groups, transmissibility and severity assessments of new variants and vaccine effectiveness.

Equity and public trust emerged as critical enabling factors. Free and accessible testing, income support for isolation and quarantine, and clear, consistent communication enhanced public compliance and helped mitigate the broader societal burden of the disease and measures taken. Simplified guidance and voluntary participation often proved more sustainable than complex legal frameworks.

The Nordic experience underlines that large-scale testing and contact tracing are vital components of early pandemic response. However, their success is context-dependent and requires adaptive strategies based on real-time systematic data gathering and usage, and strong alignment between public health, digital tools and social policy. Future preparedness should build on these lessons to ensure agile, equitable and cost-effective systems.

Work Group leader: Statens Serum Institute

The COVID-19 vaccination strategies across the Nordic region shared common objectives but were shaped by national contexts, health system capacities, and evolving epidemiological dynamics. From the onset of the pandemic through 2025, all countries prioritized reducing severe illness, hospitalizations, and deaths and protecting critical societal functions. The strategic aims for the countries shifted along with the pandemic situation. For example, Sweden changed their aim in 2021 to not focus on protection of critical societal functions apart from staff in the health and care sector. Vaccination programs began in late December 2020 and followed a phased approach. The first phases focused on high-risk groups such as the elderly, individuals with chronic illnesses and frontline healthcare personnel. As vaccine availability improved, eligibility expanded and strategies adapted to new variants, shifting risk assessments, and evidence on vaccine effectiveness.

While overarching goals were similar, the operationalization differed. Some countries, like Denmark and Finland, included healthy children in the vaccination program to bolster population-level immunity and mitigate high infection rates among young age groups as a supplement to individual protection. Others, like Sweden and Norway, limited child vaccination to those with medical vulnerabilities, citing limited direct benefit and societal impact. The transition from emergency mass vaccination to seasonal, risk-based vaccination occurred in all countries by early 2022. The seasonal programs focused on protecting older adults, people with underlying health conditions, pregnant individuals, and, in some cases, healthcare workers, although the latter group was largely phased out from official programs by 2023.

Vaccine selection followed broadly aligned patterns early in the pandemic, with Pfizer/BioNTech’s Comirnaty and Moderna’s Spikevax forming the core of national rollouts. However, the use of AstraZeneca’s Vaxzevria and Johnson & Johnson’s Jcovden was discontinued across most countries by mid-2021 due to safety concerns, particularly the risk of vaccine-induced immune thrombotic thrombocytopenia (VITT). The Nordic countries played a central role in identifying and communicating these adverse effects to the European Medicines Agency. While some countries allowed limited off-program use of these vaccines, they were quickly replaced by mRNA vaccines.

Vaccine uptake among older adults remained high throughout the pandemic, with over 90% coverage for initial doses. Among adults aged 18–64, coverage was also strong for the first two doses but declined for third and fourth doses as urgency lessened and eligibility narrowed. Coverage among adolescents varied, reflecting national decisions on youth vaccination.

A key takeaway from the Nordic experience is the value of strategic flexibility within a shared framework. The Nordic region benefited from adapting their approaches in response to supply changes, evolving evidence, and shifting public health priorities. At the same time, close Nordic regional cooperation, like alignment of strategies, and mutual learning, was instrumental in supporting rapid decision making and effective public health responses. There was great benefit from setting up informal weekly meetings on vaccine policy in a Nordic forum. Transparent sharing of data, strategies, and real-time insights supported faster decision-making and mutual trust. The Nordic collaboration has since been highlighted in WHO networks as a demonstration case on how like-minded countries can help one another by information sharing and discussion.

The pandemic highlighted the importance of combining national adaptability with cross-country collaboration. As countries move forward, integrating COVID-19 vaccination into regular public health planning, the lessons from this coordinated yet flexible response provide a solid foundation for future pandemic preparedness and vaccine policy.

Work Group Leader: National Institute of Public Health, Norway

The formal title in the manuscript is “The burden of COVID-19-related intensive care admissions in the Nordic countries, 2020–2023”

Background: The COVID-19 pandemic caused a significant burden on the population and health care systems, including intensive care units (ICU) globally. In March 2020, the Nordic countries implemented public health and social measures (PHSMs) of varying strictness to limit community transmission, save lives, and to prevent healthcare system overload. Here, we describe and compare the acute burden of COVID-19-related ICU admissions on the population in the Nordic countries in 2020–2023 to understand the impact of the COVID-19 pandemic and to inform pandemic planning.

Methods: We used data from national health registries and applied national case definitions to identify patients admitted to ICU with and due to confirmed COVID-19. We calculated the 1-month, 6-month and study-period ICU-admission incidence per 100 000 inhabitants, by age group. We described the characteristics of the patients including age, sex, length of stay, ventilatory support, and in-ICU deaths. We also calculated the proportion of patients admitted to ICU of all patients admitted to hospital due to COVID-19.

Results: In 2020–2023, 21,587 patients were admitted to ICU with COVID-19, of whom >13,000 patients due to COVID-19. Sweden had the highest cumulative incidence of patients admitted due to COVID-19 (78.5, n=8,179), and a peak incidence twice that of the other countries. The proportion of patients admitted to ICU of all patients admitted to hospital due to COVID-19 varied from 16–25% in H1-2020 to 2–4% in 2022–2023. The median age of ICU patients increased over time in all countries, and the majority (62–72%) of patients were men. The longest median length of stay decreased from 6–14 days in 2020–2021 was recorded in Norway (median 14, lower - upper quartile 7–23.5 days), and it decreased to 2, 3 or 4 days in most countries to 2–7 days in 2022–2023. Seventy-nine percent of patients received ventilatory support and 25% died, with increasing in-ICU mortality in Norway and Sweden towards 2023. Differences in data sources and case definitions limited the comparability of the countries.

Discussion and conclusions: This study utilizing nationwide registry data used for routine surveillance of severe COVID-19 showed that the burden of ICU admissions was influenced both by non-modifiable risk factors such as high age and male sex, and by dynamic changes, including the intensity of community transmission, the emergence of new SARS-CoV-2 variants, developments in the care of COVID-19, and increasing immunity in the population following vaccination, infection or both. The cumulative incidence of ICU admissions over the whole study period was highest in Sweden, reflecting more intense community transmission in the country in 2020 and H1-2021. Despite the lower virulence, the increased transmissibility of the Omicron variant compared to previous variants, led to a peak in the incidence of patients admitted to ICU with COVID-19 in most Nordic countries in late 2021 – early 2022. However, disease severity decreased in terms of the proportion of hospitalized COVID-19 patients receiving intensive care, and length of stay in ICU due to the lower virulence, increasing immunity in the population and advances in the treatment of severe COVID-19. In early 2022, PHSMs were relaxed, and patients with suboptimal immune responses to vaccination due to old age and/or immunosuppression became overrepresented among patients in ICUs, often with fatal outcomes.

While the differences between the data sources used by each country and the lack of common case definitions limit the comparability of the data to some extent, assessments like the present study can provide valuable information on the burden of pandemic respiratory infections. Continued high-quality surveillance, research preparedness and further research on the implications of PHSMs for the severity of disease are needed for being better prepared for future pandemics. Close collaboration between the Nordic countries in pandemic preparedness planning, including the alignment of case definitions and protocols, will increase the quality of such research and future comparisons between the countries.

Work Group Leader: Finnish Institute for Health and Welfare

Overview: In the Nordic countries, several types of border-related measures were implemented at various points during the pandemic in an effort to reduce the risk of cross-border transfer of the virus and subsequent domestic transmission from individuals arriving from abroad. These measures supplemented intra-country interventions aimed at slowing down the epidemic. As new virus variants emerged, border measures were intended to delay their introduction to each respective country.

An assessment of the usefulness of the measures is limited by the small number of formal evaluations. In principle, any measure that reduces any significant contact between people has the potential to lower transmission. However, the impact of such measures must be weighed against both the effectiveness of alternative interventions and their broader consequences, such as economic costs and restrictions on individual freedom of movement. Use of border measures were questioned throughout the pandemic, including in the Nordic countries where free movement between areas is one of the defining features of the Nordic Region. Previously border measures limiting the movement of people between the countries and autonomous areas have been minimal.

The policies, legal basis and implementation of measures varied greatly between countries. There were differences between the broad goals, policies, mitigation measures and implementation timelines. However, discussion of border measures was continuously ongoing between Nordic Public Health Institutes and situation awareness information was shared regularly and this collaboration was critical to be able to assess, without results from formal evaluations, the observations of possible impacts of each measure.

Project description: The project for the border control measures was focused on a qualitative approach to questions related to mitigation measures taken at borders. All Nordic public health institutes and representatives of Åland and the Faroe Islands were provided with four key questions. To help answer, a tool was also provided to be used internally by the institutes to record the implementation time of measures and their legislative background.

Questions

1. Were travel restrictions useful in limiting domestic transmission in the destination country, and if so under what conditions?
2. Did the use of post-arrival quarantine help reduce transmission in the destination country, and if so under what conditions?
3. Did the use of mass-testing/screening (pre- or post-arrival, compulsory or voluntary, single or multiple, PCR or ag) significantly reduce transmission in the destination country, and if so under what conditions?
4. Did the use of vaccine certificates significantly reduce transmission in the destination country, and if so under what conditions?

Results; The following is a summary of the answers received

Question 1During the early stages of the COVID-19 pandemic, most confirmed cases were travel-related, with a focus on China, particularly Wuhan. By March 2020, Nordic travellers contracted the virus, for example, at European ski resorts, highlighting the challenges in containing the virus. Initial border control measures were implemented amid rapidly increasing number of cases, and earlier implementation might have been more effective, though this is difficult to assess due to limited testing capacity at the time.

Travel restrictions, combined with recommendations, global epidemiological situation and overall, less travel, significantly reduced cross-border travel within the Nordics, particularly affecting tourism during 2020 and 2021, but also travel for work, family contacts and social life. Travel restrictions between countries with similar epidemiology have little effect. Targeted restrictions on travellers from specific countries, often linked to reports of new variants, can be perceived as punitive for the country that reports, hence potentially discouraging international cooperation in future outbreaks.

Question 2If entry measures like quarantine are imposed in settings where incidences between countries are similar, quarantining of incoming travellers still likely is less effective than spending the same resources on targeted domestic interventions. Even in countries with high infection rates, the probability of a random entrant being infected is lower than that of someone known to be exposed, such as a close contact.

Question 3Testing alone is insufficient to break transmission chains and must be integrated with other measures. Post-arrival testing is a component of the broader contact tracing system aimed at identifying infected individuals and disrupting transmission. In the early stages of the pandemic, pre- and post-arrival testing might have played a role in potentially preventing the introduction of new cases from the epicentre. This, however, would have been strongly dependent on the level of testing capacity. However, as the pandemic progressed and it became difficult to identify a single epidemic centre, these testing measures lost their unique significance.

Question 4Vaccine certificates have been used in points of entry and in some Nordic countries in public settings to potentially reduce COVID-19 transmission by limiting the importation of cases from countries with higher infection rates. The implementation of vaccine certificates highlighted the limited and temporary efficacy of vaccines in reducing the risk of infection and onward transmission, particularly emphasised in autumn 2021. Related to the limited efficacy it is possible that vaccinations and certificates could have significantly reduced transmission only in the first half of 2021, applicable to both border crossings and domestic use. Theoretically, certificates might have increased transmission risk due to a false sense of security.

Conclusion: The impact of border restrictions, quarantine, testing, and travel certificates on transmission within the country remains uncertain. Formal evaluations of these measures are scarce. While reduced mobility globally (and domestically) likely contributed to less transmission and illness, this was primarily due to general decrease in travel. Most of the spread from “imported” cases was more likely from returning residents as tourists, in general, have minimal close contact with residents. The effectiveness of domestic border regulations in reducing transmission is unclear, especially after the virus had already been introduced in a country. Travel restrictions were most stringent early in the pandemic before widespread immunity from vaccinations and infections. Testing and quarantine made most sense when infection risks were higher in the country of origin, though evaluating this was challenging. The measures were based on political considerations. Expert opinion was commonly the basis for border decisions since there was limited or no empirical evidence and no comprehensive retrospective analysis conducted. In our qualitative assessment, the impact of the measures taken at borders were considered to be marginally effective at best.

Work Group Leader: Directorate of Health, Iceland

Following the COVID-19 pandemic, the governments of the Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden), as well as the governments of Åland and the Faroe Islands, conducted after-action reviews (AARs) and assessments to different degrees. These efforts aimed not only to document how the pandemic was managed but, more importantly, to identify lessons learned that can strengthen future pandemic preparedness. The aim of this part of the Nordic Pandemic Follow-Up project was to identify the reports commissioned and produced by national authorities in each Nordic country and compile them into a joint Nordic report with a comprehensive overview.

The objective was to provide a comprehensive overview of the national lessons learned from the pandemic across the region. Each country’s representative in the working group was responsible for collecting the relevant reports from their respective country and preparing a brief summary for each report.

A total of 30 reports were identified including a scientific report from Greenland. The topics have been categorized as follows.

1. Governance, legislation, decision making, role division between authorities, etc.
2. General analysis of the epidemiological development and response measures
3. Specific pandemic response measures and their effectiveness in terms of prevention, control, transmission, and health impact from Covid-19
4. Reports on the regional response (in-countries)
5. Other reports

The country reports vary in structure, content and cover different periods of the pandemic. Some of them only cover the first or second wave, while others cover most of the pandemic period. The different structure and content of the reports and the period the reports cover make it more difficult to create a proper comparison between the Nordic countries when looking at the lessons learned. However, some of them may be comparable, and it should be considered to create a comparison on similar topics, where the reports are similar in structure. This should be considered in the future, although not within the scope of this project.

One key lesson learned during the process of compiling these reports is the importance of considering AARs at the beginning of a pandemic. Early planning of AARs would allow for timely discussions on adopting a uniform or standardized approach to documenting lessons learned across the Nordic countries. This would enhance the comparability and readability of AARs and support cross-country learning.

Furthermore, the Nordic countries should consider a broader collaboration on AAR processes at the beginning of any multi-national crisis, such as a pandemic. Joint AARs on overarching issues, such as border-related measures, would provide a valuable regional prespective. This needs to be a part of the preparedness process and should be considered, for instance, in the pandemic preparedness plans.

Additionally, it is important to note that the majority of the reports identified did not contain an English summary and only a few reports presented parts of their work as scientific papers (as secondary publications). We suggest that this be encouraged in the future to improve the quality of the work by a peer review process and also to disseminate the important lessons to a broader audience.

AAR – After Action Review

COVID-19 – coronavirus disease

ECDC – European Centre for Disease Prevention and Control

IANPHI - International Association of National Public Health Institutes

ICU – Intensive Care Units

IHR – International Health Regulations

NIPH Norwegian Institute of Public Health

NPI – National Public Health Institute

PHSMs - Public Health and Social Measures

SARS-CoV-2 - Severe Acute Respiratory Syndrome Coronavirus 2

SSI - Statens Serum Institut

THL - Finnish Institute for Health and Welfare

WHO – World Health Organization