Poor neutralizing antibody responses against SARS-CoV-2 Omicron BQ.1.1 and XBB in Norway in October 2022.

New immune evasive variants of SARS-CoV-2 continue to emerge, potentially causing new waves of covid-19 disease. Here, we evaluate levels of neutralizing antibodies against isolates of Omicron variants, including BQ.1.1 and XBB, in sera harvested 3-4 weeks after vaccination or breakthrough infections. In addition, we evaluate neutralizing antibodies in 32 sera from October 2022, to evaluate immunity in Norwegian donors prior to the winter season. Most serum samples harvested in October 2022 had low levels of neutralizing antibodies against BQ.1.1 and especially XBB, explaining why these variants and their descendants have dominated in Norway during the 2022 and 2023 winter season.

Prevalence and factors associated with healthcare avoidance during the COVID-19 pandemic among the Sámi in Sweden: the SámiHET study.

The aim of this population-based cross-sectional study was to assess the prevalence of healthcare avoidance during the COVID-19 pandemic and its associated factors among the Sámi population in Sweden. Data from the "Sámi Health on Equal Terms" (SámiHET) survey conducted in 2021 were used. Overall, 3,658 individuals constituted the analytical sample. Analysis was framed using the social determinants of health framework. The association between healthcare avoidance and several sociodemographic, material, and cultural factors was explored through log-binomial regression analyses. Sampling weights were applied in all analyses. Thirty percent of the Sámi in Sweden avoided healthcare during the COVID-19 pandemic. Sámi women (PR: 1.52, 95% CI: 1.36-1.70), young adults (PR: 1.22, 95% CI:1.05-1.47), Sámi living outside Sápmi (PR: 1.17, 95% CI: 1.03-1.34), and those having low income (PR: 1.42, 95% CI:1.19-1.68) and experiencing economic stress (PR: 1.48, 95% CI: 1.31-1.67) had a higher prevalence of healthcare avoidance. The pattern shown in this study can be useful for planning future pandemic responses, which should address healthcare avoidance, particularly among the identified vulnerable groups, including the active participation of the Sámi themselves.

Current tobacco use and SARS-CoV-2 infection in two Norwegian population-based cohorts.

BACKGROUND: Clear evidence of an increased risk for SARS-CoV-2 infection among smokers has not been established. We aimed to investigate associations between cigarette smoking or use of snus (snuff) and other nicotine-containing products and a positive SARS-CoV-2 test, taking test behavior into account. METHODS: Current tobacco use and testing behavior during the pandemic were recorded by adult participants from the Norwegian Mother, Father and Child Cohort Study and The Norwegian Influenza Pregnancy Cohort. SARS-CoV-2 infection status was obtained from The Norwegian Surveillance System for Communicable Diseases (MSIS) in May 2021 (n = 78,860) and antibody measurements (n = 5581). We used logistic regression models stratified by gender and adjusted for age, education, region, number of household members, and work situation. RESULTS: Snus use was more common among men (26%) than women (9%) and more prevalent than cigarette smoking. We found no clear associations between cigarette smoking or snus and a COVID-19 diagnosis among men. Associations among women were conflicting, indicating that cigarette smoke was negatively associated with a diagnosis (OR 0.51, 95% CI 0.35, 0.75), while no association was found for snus use (OR 1.07, 95% CI 0.86, 1.34). Compared with non-users of tobacco, both cigarette smokers and snus users had increased odds of being tested for SARS-CoV-2. CONCLUSIONS: Cigarette smoking, but not snus use, was negatively associated with SARS-CoV-2 infection in women. The lack of an association between snus use and SARS-CoV-2 infection in this population with prevalent snus use does not support the hypothesis of a protective effect of nicotine.

COVID-19 vaccination rates among adolescents (12-17 years) by immigrant background and sociodemographic factors: A nationwide registry study in Norway.

PURPOSE: Lower COVID-19 vaccination rates have been observed among some adult immigrant populations in Norway, and there appears to be an association with sociodemographic factors. However, knowledge is lacking on the distribution of vaccination rates and role of sociodemographic factors among adolescents. This study aims to describe COVID-19 vaccination rates among adolescents according to immigrant background, household income, and parental education. METHODS: In this nationwide registry study, we analyzed individual-level data on adolescents (12-17 years) from the Norwegian Emergency preparedness register for COVID-19 until September 15th, 2022. We estimated incidence rate ratios (IRR) for receiving at least one COVID-19 vaccine dose by country background, household income and parental education, using Poisson regression, adjusting for age, sex, and county. RESULTS: The sample comprised 384,815 adolescents. Foreign-born and Norwegian-born with foreign-born parents, had lower vaccination rates (57 % and 58 %) compared to adolescents with at least one Norwegian-born parent (84 %). Vaccination rates by country background varied from 88 % (Vietnam) to 31 % (Russia). Variation and associations by country background, household income, and parental education were greater among 12-15-year-olds than 16-17-year-olds. Household income and parental education were positively associated with vaccination. Compared to the lowest income and education category, IRRs for household income ranged from 1.07 (95 % CI 1.06-1.09) to 1.31 (95 % CI 1.29-1.33) among 12-15-year-olds, and 1.06 (95 % CI 1.04-1.07) to 1.17 (95 % CI 1.15-1.18) among 16-17-year-olds. For parental education, from IRR 1.08 (95 % CI 1.06-1.09) to 1.18 (95 % CI 1.17-1.20) among 12-15-year-olds, and 1.05 (95 % CI 1.04-1.07) to 1.09 (95 % CI 1.07-1.10) among 16-17-year-olds. CONCLUSION: COVID-19 vaccination rates varied by immigrant background and age group, with lower rates especially among adolescents with background from Eastern Europe and among younger adolescents. Household income and parental education were positively associated with vaccination rates. Our results may help target measures to increase vaccination rates among adolescents.

The COVID-19 pandemic and the timing of government response: A comparison of four Nordic countries March-June 2020.

OBJECTIVES: The aim is to compare Sweden, Denmark, Finland and Norway regarding government response to the COVID-19 pandemic in mid-March-June 2020 using the Oxford Government Response Tracker. STUDY DESIGN: Descriptive longitudinal ecological study. METHODS: Descriptive analysis of time series data. RESULTS: Sweden displayed a far lower response index in March. By late April indexes were similar. In May-June, response indexes were lower in Finland and Norway than in Sweden. The average response index in mid-March-June was similar in Sweden, Finland and Norway. CONCLUSIONS: The government response in the four countries indicates that timing of response was essential. Sweden's slow and weak initial government response in March-April was followed by less loosening of government response in May-June compared with, especially, Finland and Norway, which resulted in similar average government response in mid-March-June for the three countries. As a comparison, COVID-19 mortality per capita was 10 times higher in Sweden than in Finland and Norway, and five times higher than in Denmark during the same period.

Effects of non-compulsory and mandatory COVID-19 interventions on travel distance and time away from home, Norway, 2021.

BackgroundGiven the societal, economic and health costs of COVID-19 non-pharmaceutical interventions (NPI), it is important to assess their effects. Human mobility serves as a surrogate measure for human contacts and compliance with NPI. In Nordic countries, NPI have mostly been advised and sometimes made mandatory. It is unclear if making NPI mandatory further reduced mobility.AimWe investigated the effect of non-compulsory and follow-up mandatory measures in major cities and rural regions on human mobility in Norway. We identified NPI categories that most affected mobility.MethodsWe used mobile phone mobility data from the largest Norwegian operator. We analysed non-compulsory and mandatory measures with before-after and synthetic difference-in-differences approaches. By regression, we investigated the impact of different NPI on mobility.ResultsNationally and in less populated regions, time travelled, but not distance, decreased after follow-up mandatory measures. In urban areas, however, distance decreased after follow-up mandates, and the reduction exceeded the decrease after initial non-compulsory measures. Stricter metre rules, gyms reopening, and restaurants and shops reopening were significantly associated with changes in mobility.ConclusionOverall, distance travelled from home decreased after non-compulsory measures, and in urban areas, distance further decreased after follow-up mandates. Time travelled reduced more after mandates than after non-compulsory measures for all regions and interventions. Stricter distancing and reopening of gyms, restaurants and shops were associated with changes in mobility.

Invasive meningococcal disease in Norway in the two decades before the COVID-19 pandemic.

OBJECTIVES: Disease caused by the bacterium Neisseria meningitidis remains a worldwide public health challenge, despite the steadily decreasing incidence in Western countries. The objective of this study was to explore the epidemiology of invasive meningococcal disease in Norway over the last two decades. DESIGN: All isolates sent to the National Reference Laboratory from patients with invasive meningococcal disease between the years 2000 and 2019 were analyzed using whole genome sequencing (total: 625). RESULTS: A five-fold decrease in case numbers occurred over this period, and the situation has gone from being dominated by serogroup B to one where serogroups Y and W are more prevalent. Concurrently, the mean age at infection has increased from 18 to 33 years. Among the 350 serogroup B isolates, 87% were an exact match or cross-reactive with one or both the currently available serogroup B vaccines, but the proportion decreased in the past decade. Core genome analyses revealed a high variation in the number of allelic differences accumulated in epidemiologically linked isolates to the point that near-identical isolates were found several years apart. CONCLUSION: Allelic distance is an imprecise metric for the degree of epidemiologic linkage between isolates in N. meningitidis.

Managers' strategies in handling the COVID-19 pandemic in Norwegian nursing homes and homecare services.

PURPOSE: This study aims to explore nursing home and home care managers' strategies in handling the COVID-19 pandemic. DESIGN/METHODOLOGY/APPROACH: This study has a qualitative design with semistructured individual interviews conducted digitally by videophone (Zoom). Eight managers from nursing homes and five managers from home care services located in a large urban municipality in eastern Norway participated. Systematic text condensation methodology was used for the analysis. FINDINGS: The managers used several strategies to handle challenges related to the COVID-19 pandemic, including being proactive and thinking ahead in terms of possible scenarios that might occur, continuously training of staff in new procedures and routines and systematic information sharing at all levels, as well as providing different ways of disseminating information for staff, service users and next-of-kins. To handle staffing challenges, managers used strategies such as hiring short-term staff that were temporary laid off from other industries and bringing in students. ORIGINALITY/VALUE: The COVID-19 pandemic heavily affected health-care systems worldwide, which has led to many health-care studies. The situation in nursing homes and home care services, which were strongly impacted by the pandemic and in charge of a vulnerable group of people, has not yet received enough attention in research. This study, therefore, seeks to contribute to this research gap by investigating how managers in nursing homes and home care services used different strategies to handle the COVID-19 pandemic.

Tension between local, regional and national level in Norwegian handling of COVID-19.

INTRODUCTION: The initial phase of the COVID-19 pandemic can be described as a crisis - a threat that must be urgently addressed under conditions of deep uncertainty. We wanted to explore the tension between local, regional and national authorities evoked by some rural municipalities' decisions to impose local infection control measures during the first weeks of the COVID-19 pandemic in Norway. METHODS: Eight municipal chief medical officers of health (CMO) and six crisis management teams participated in semi-structured and focus group interviews. Data were analyzed with systematic text condensation. Boin and Bynander's interpretation of crisis management and coordination and Nesheim et al.'s framework for non-hierarchical coordination in the state sector inspired the analysis. RESULTS: Uncertainty in the face of a pandemic with unknown damage potential, lack of infection control equipment, patient transport challenges, vulnerable staff situation and planning of local COVID-19 beds were some of the reasons for rural municipalities imposing local infection control measures. Local CMOs' engagement, visibility and knowledge contributed to trust and safety. Differences in perspectives between local, regional and national actors created tension. Existing roles and structures were adjusted, and new informal networks arose. DISCUSSION: Strong municipal responsibility in Norway and the quite unique arrangement with local CMOs in every municipality with legal right to decide temporary local infection control measures seemed to facilitate a fruitful balance between top-down and bottom-up decision-making. The following dialogue and mutual adjustment of perspectives led to appropriate balance between national and local measures in Norway's handling of the COVID-19 pandemic.

Nature visits during the COVID-19 pandemic in Norway: Facilitators, motives, and associations with sociodemographic characteristics.

Introduction: The COVID-19 pandemic has been linked to increased mental health issues and reduced well-being. Researchers also reports increased frequency of nature visits during the pandemic, proposing it may mitigate some of these negative consequences. Using the case of Norway, a country with ample access to nature and relatively low levels of pandemic-related restrictions, this study sought to (i) understand how the COVID-19 crisis impacted patterns of nature visits and specific nature-based activities, (ii) examine how these patterns varied among different population groups and levels of restrictions, and (iii) explore the motives and facilitators for increased frequency of nature visits. Methods: The data were retrieved from a national cross-sectional survey conducted in June 2021, which was designed to assess participants (n = 1,005, age > 15 years) habits in relation to nature visits and outdoor recreation since the beginning of the COVID-19 crisis, and associated factors. Results: The results showed that 32 % of participants increased their frequency of nature visits during the crisis, while 11 % experienced a decrease. Multivariate logistic regression revealed significant positive associations between increased frequency of nature visits and longer duration of lockdown restrictions (OR [95% CI] = 2.35 [1.28-4.29] and 4.92 [2.77-8.74] for a few weeks and several months of lockdown, respectively). Increased frequency of nature visits was also more likely among women, younger respondents, and individuals from high-income households. A Cochran's Q test showed that the most common motive for increased frequency of nature visits was "To be physically active" (74%). The most commonly reported facilitators were the possibility of using natural environments as an alternative to gyms and organized sports alongside having more time available (58 and 49%, respectively). Conclusion: These findings suggest that nature visits provided important opportunities for physical activity during the COVID-19 crisis, but also that the mental health benefits of nature visits during such times may be under-communicated. This highlights the importance of access to natural environments to promote physical activity and health, but also suggests that campaigns that specifically communicate the beneficial effects of nature visits during lockdowns or similar stressful situations might help people cope with the situation.

Quality of life and associated factors among Norwegian public health nurse students during the first months of the COVID-19 pandemic: A cross-sectional study.

The main objective of this study was to investigate the association between quality of life (QOL) and civil status, self-efficacy, loneliness, and physical and mental health among public health nurse (PHN) students during the COVID-19 pandemic in April 2020. PHN students were recruited from eight universities and university colleges in Norway. A range of potential predictive factors were entered into a model using a stepwise linear regression approach. In general, the PHN students reported a high level of QOL during the first month of the pandemic. The students' civil status, perceived physical health, self-efficacy and loneliness were all significantly correlated with QOL. Among these, the strongest predictive factors for QOL were found to be perceived loneliness and self-efficacy. Our results provide insight into the QOL of PHN students, which managers in the higher education sector can use to outline specific coping strategies that can help students during a pandemic.

Clusters of healthcare-associated SARS-CoV-2 infections in Norwegian hospitals detected by a fully automatic register-based surveillance system.

BACKGROUND: Notifications to the Norwegian Institute of Public Health of outbreaks in Norwegian healthcare institutions are mandatory by law, but under-reporting is suspected due to failure to identify clusters, or because of human or system-based factors. This study aimed to establish and describe a fully automatic, register-based surveillance system to identify clusters of healthcare-associated infections (HAIs) of SARS-CoV-2 in hospitals and compare these with outbreaks notified through the mandated outbreak system Vesuv. METHODS: We used linked data from the emergency preparedness register Beredt C19, based on the Norwegian Patient Registry and the Norwegian Surveillance System for Communicable Diseases. We tested two different algorithms for HAI clusters, described their size and compared them with outbreaks notified through Vesuv. RESULTS: A total of 5033 patients were registered with an indeterminate, probable, or definite HAI. Depending on the algorithm, our system detected 44 or 36 of the 56 officially notified outbreaks. Both algorithms detected more clusters then officially reported (301 and 206, respectively). CONCLUSIONS: It was possible to use existing data sources to establish a fully automatic surveillance system identifying clusters of SARS-CoV-2. Automatic surveillance can improve preparedness through earlier identification of clusters of HAIs, and by lowering the workloads of infection control specialists in hospitals.

A first-level customization study of SAPS II with Norwegian Intensive Care and Pandemic Registry (NIPaR) data.

BACKGROUND: Severity scores and mortality prediction models (MPMs) are important tools for benchmarking and stratification in the intensive care unit (ICU) and need to be regularly updated using data from a local and contextual cohort. Simplified acute physiology score II (SAPS II) is widely used in European ICUs. METHODS: A first-level customization was performed on the SAPS II model using data from the Norwegian Intensive Care and Pandemic Registry (NIPaR). Two previous SAPS II models (Model A: the original SAPS II model and Model B: a SAPS II model based on NIPaR data from 2008 to 2010) were compared to the new Model C. Model C was based on patients from 2018 to 2020 (corona virus disease 2019 patients omitted; n = 43,891), and its performances (calibration, discrimination, and uniformity of fit) compared to the previous models (Model A and Model B). RESULTS: Model C was better calibrated than Model A with a Brier score 0.132 (95% confidence interval 0.130-0.135) versus 0.143 (95% confidence interval 0.141-0.146). The Brier score for Model B was 0.133 (95% confidence interval 0.130-0.135). In the Cox's calibration regression α ≈ 0 and ß ≈ 1 for both Model C and Model B but not for Model A. Uniformity of fit was similar for Model B and for Model C, both better than for Model A, across age groups, sex, length of stay, type of admission, hospital category, and days on respirator. The area under the receiver operating characteristic curve was 0.79 (95% confidence interval 0.79-0.80), showing acceptable discrimination. CONCLUSIONS: The observed mortality and corresponding SAPS II scores have significantly changed during the last decades and an updated MPM is superior to the original SAPS II. However, proper external validation is required to confirm our findings. Prediction models need to be regularly customized using local datasets in order to optimize their performances.

Women's experiences and views on early breastfeeding during the COVID-19 pandemic in Norway: quantitative and qualitative findings from the IMAgiNE EURO study.

BACKGROUND: Little is known about women's experience of care and views on early breastfeeding during the COVID-19 pandemic in Norway. METHODS: Women (n = 2922) who gave birth in a facility in Norway between March 2020 and June 2021 were invited to answer an online questionnaire based on World Health Organization (WHO) Standard-based quality measures, exploring their experiences of care and views on early breastfeeding during the COVID-19 pandemic. To examine associations between year of birth (2020, 2021) and early breastfeeding-related factors, we estimated odds ratios (ORs) with 95% confidence intervals (CIs) using multiple logistic regression. Qualitative data were analysed using Systematic Text Condensation. RESULTS: Compared to the first year of the pandemic (2020), women who gave birth in 2021 reported higher odds of experiencing adequate breastfeeding support (adjOR 1.79; 95% CI 1.35, 2.38), immediate attention from healthcare providers when needed (adjOR 1.89; 95% CI 1.49, 2.39), clear communication from healthcare providers (adjOR 1.76; 95% CI 1.39, 2.22), being allowed companion of choice (adjOR 1.47; 95% CI 1.21, 1.79), adequate visiting hours for partner (adjOR 1.35; 95% CI 1.09, 1.68), adequate number of healthcare providers (adjOR 1.24; 95% CI 1.02, 1.52), and adequate professionalism of the healthcare providers (adjOR 1.65; 95% CI 1.32, 2.08). Compared to 2020, in 2021 we found no difference in skin-to-skin contact, early breastfeeding, exclusive breastfeeding at discharge, adequate number of women per room, or women's satisfaction. In their comments, women described understaffed postnatal wards, early discharge and highlighted the importance of breastfeeding support, and concerns about long-term consequences such as postpartum depression. CONCLUSIONS: In the second year of the pandemic, WHO Standard-based quality measures related to breastfeeding improved for women giving birth in Norway compared to the first year of the pandemic. Women's general satisfaction with care during COVID-19 did however not improve significantly from 2020 to 2021. Compared to pre-pandemic data, our findings suggest an initial decrease in exclusive breastfeeding at discharge during the COVID-19 pandemic in Norway with little difference comparing 2020 versus 2021. Our findings should alert researchers, policy makers and clinicians in postnatal care services to improve future practices.

Effectiveness of BNT162b2 vaccine against SARS-CoV-2 Delta and Omicron infection in adolescents, Norway, August 2021 to January 2022.

OBJECTIVES: We estimated the BNT162b2 vaccine effectiveness (VE) against any (symptomatic or not) SARS-CoV-2 Delta and Omicron infection among adolescents (aged 12-17 years) in Norway from August 2021 to January 2022. METHODS: We used Cox proportional hazard models, where vaccine status was included as a time-varying covariate and models were adjusted for age, sex, comorbidities, residence county, birth country, and living conditions. RESULTS: The VE against Delta infection peaked at 68% (95% confidence interval [CI]: 64-71%) and 62% (95% CI: 57-66%) in days 21-48 after the first dose among those aged 12-15 years and 16-17 years, respectively. Among those aged 16-17 years who received two doses, the VE against Delta infection peaked at 93% (95% CI: 90-95%) in days 35-62 and decreased to 84% (95% CI: 76-89%) in ≥63 days after vaccination. We did not observe a protective effect against Omicron infection after receiving one dose. Among those aged 16-17 years, the VE against Omicron infection peaked at 53% (95% CI: 43-62%) in 7-34 days after the second dose and decreased to 23% (95% CI: 3-40%) in ≥63 days after vaccination. CONCLUSION: We found a reduced protection after two BNT162b2 vaccine doses against any Omicron infection compared to Delta. Effectiveness decreased with time from vaccination for both variants. The impact of vaccination among adolescents on reducing infection and thus transmission is limited during the Omicron dominance.

Emotional Eating and Changes in High-Sugar Food and Drink Consumption Linked to Psychological Distress and Worries: A Cohort Study from Norway.

Psychological distress is linked to unhealthy eating behaviors such as emotional eating and consumption of high-sugar food and drinks. Cross-sectional studies from early in the COVID-19 pandemic showed a high occurrence of worries and psychological distress, and this was associated with emotional eating. Few larger studies have examined how this coping pattern develops over time. This cohort study with 24,968 participants assessed changes over time in emotional eating, consumption of sugary foods as an example of unhealthy food choices, and consumption of fruits and vegetables as an example of healthy food choices. Further, associations between these and psychological distress, worries, and socio-demographic factors were assessed. Data were collected at three time points (April 2020, initially in the COVID-19 pandemic, then one and two years later). Emotional eating and intake of sugary foods and drinks were high at the start of the pandemic, followed by a reduction over time. High psychological distress was strongly associated with higher levels of emotional eating and high-sugar food intake, and lower levels of healthy eating habits. The strength of this association reduced over time. Our findings indicate the high frequency in unhealthy food choices seen early in the COVID-19 pandemic improved over time.

Social and demographic patterns of influenza vaccination coverage in Norway, influenza seasons 2014/15 to 2020/21.

AIMS: To examine influenza vaccination coverage among risk groups (RG) and health care workers (HCW), and study social and demographic patterns of vaccination coverage over time. METHODS: Vaccination coverage was estimated by self-report in a nationally representative telephone survey among 14919 individuals aged 18-79 years over seven influenza seasons from 2014/15 to 2020/21. We explored whether belonging to an influenza RG (being >=65 years of age and/or having >=1 medical risk factor), being a HCW or educational attainment was associated with vaccination status using logistic regression. RESULTS: Vaccination coverage increased from 27 % to 66 % among individuals 65-79 years, from 13 % to 33 % among individuals 18-64 years with >=1 risk factor, and from 9 % to 51 % among HCWs during the study period. Being older, having a risk factor or being a HCW were significantly associated with higher coverage in all multivariable logistic regression analyses. Higher education was also consistently associated with higher coverage, but the difference did not reach significance in all influenza seasons. Educational attainment was not significantly associated with coverage while coverage was at its lowest (2014/15-2017/18), but as coverage increased, so did the differences. Individuals with intermediate or lower education were less likely to report vaccination than those with higher education in season 2018/19, OR = 0.61 (95 % CI 0.46-0.80) and OR = 0.58 (95 % CI 0.41-0.83), respectively, and in season 2019/20, OR = 0.69 (95 % CI 0.55-0.88) and OR = 0.71 (95 % CI 0.53-0.95), respectively. When the vaccine was funded in the COVID-19 pandemic winter of 2020/21, educational differences diminished again and were no longer significant. CONCLUSIONS: We observed widening educational differences in influenza vaccination coverage as coverage increased from 2014/15 to 2019/20. When influenza vaccination was funded in 2020/21, differences in coverage by educational attainment diminished. These findings indicate that economic barriers influence influenza vaccination decisions among risk groups in Norway.

Letter to the editor regarding "Covid-19 transmission in fitness centers in Norway - a randomized trial".

In a recently published paper in BMC Public Health we read about a randomized trial on Covid-19 transmission performed in five fitness centers in Oslo, Norway, during the spring of 2020. In our opinion, this study has major shortcomings in design and methodology, which have not been addressed by the authors.

Reply to: Letter to the Editor regarding "Covid-19 transmission in fitness centers in Norway-a randomized trial".

In this correspondence we respond to critique of our randomized trial of Covid-19 transmission in fitness centers. The trial was performed in Norway during May and June 2020.