Federal Office of Public Health

Thin layer chromatography scanners and dose calibrators are commonly used to assess radiochemical purity of radiopharmaceutical preparations. Strict quality assurance programs surveyed by regulatory bodies exist for dose calibrators, but they primarily focus on clinical activity ranges, typically tens to hundreds of megabecquerels (MBq). These programs are not designed to evaluate performance at the lower activity levels used during radiopharmaceutical quality control, in the range of just a few MBq or less. For thin layer chromatography scanners, to our knowledge, no supervised quality control program exists. As a result, current practices may overlook potential inaccuracies at these low but critical activity levels, potentially affecting the reliability of radiochemical purity assessments, guaranteeing radiopharmaceutical quality of patient injections. To address this gap, in collaboration with the Swiss Federal Office of Public Health, we organized an intercomparison campaign for radiochemical purity testing employing in-house fabricated cobalt-57 (Co-57) strips simulating a chromatogram of a radiopharmaceutical preparation for quality control. Co-57, with its longer half-life, closely simulates the gamma emissions of technetium-99m (Tc-99m), a nuclide widely used in nuclear medicine. Co-57 thin layer chromatography strips were prepared and characterized, before being sent to nuclear medicine centers for measurement and radiochemical purity assessment. 31 centers participated, in total 41 quality control measurements were performed using dose calibrators and/or thin layer chromatography scanners to assess the radiochemical purity. All 27 dose calibrator results were within specifications, except for one result that overestimated the radiochemical purity. Within 14 thin layer chromatography scanner results, 3 were out of tolerance. Regular participation in intercomparison campaigns is essential for harmonizing practices and ensuring reproducible, reliable results. Thin layer chromatography results can be affected by scanner settings, procedural variations, and subjective peak integration. By comparing thin layer chromatography scanners and dose calibrators, we identified potential instrument biases and methodological discrepancies when values were out of tolerance. Our intercomparison contributed to improving the performance and comparability of radiochemical purity measurements across Swiss nuclear medicine institutions.

<h2>Abstract</h2><h3>Objectives</h3> We aimed to describe recent epidemiological trends of SARS-CoV-2, influenza virus (A/B), and respiratory syncytial virus (RSV) in the canton of Geneva, Switzerland, using data from the Sentinella network for primary care consultations, hospital-based surveillance at Geneva University Hospitals and municipal wastewater surveillance conducted by Eawag, the Swiss Federal Institute of Aquatic Science and Technology. <h3>Methods</h3> We described the temporal trends in weekly SARS-CoV-2, influenza virus (A/B), and RSV infections among primary care consultations, hospitalized patients and the mean normalized viral load per week for SARS-CoV-2, influenza virus (A/B), and RSV from wastewater samples between 1 July 2022 and 30 April 2025. We used Kendall's rank correlation (τ) to assess the correlation between the viral RNA loads in wastewater and SARS-CoV-2, influenza A, and RSV infections among hospitalized patients between 1 September 2024 and 30 April 2025. <h3>Results</h3> The period from September 2024 to April 2025 was the first extended winter season since the beginning of the COVID-19 pandemic, during which SARS-CoV-2 activity remained consistently lower than previous seasons across all surveillance systems. In contrast, influenza activity was higher than in recent prior winter seasons. There was a decrease in the number of RSV hospitalizations during the 2024–2025 winter season. The associations between wastewater loads and infections were significant and positive for SARS-CoV-2 (τ = 0.75; p <0.01), influenza A (τ = 0.80; p <0.01), and RSV (τ = 0.68; p <0.01). <h3>Conclusions</h3> Our findings contribute to understanding the evolving epidemiology of COVID-19 in relation to the two other respiratory viruses (influenza and RSV) across complementary surveillance systems.

Introduction: Extubation in intensive care units (ICUs) is a complex process with a high failure rate and significant impact on clinical outcomes. In a public tertiary hospital in the Federal District, the lack of a standardized protocol results in variations in procedures and risks to patients. The literature highlights the importance of standardization to reduce complications and mortality. Objective: Propose an institutional extubation protocol for critically ill patients in the Intensive Care Units of a public hospital in the Federal District, aiming at standardizing the criteria, conduct and care involved in this procedure. Methodology: This study consisted of a narrative review of literature with a qualitative approach. The bibliographic search was conducted in the PubMed, Scielo and Embase databases. The study was structured in three main stages: survey and analysis of the scientific literature; comparison between the current recommendations found in the literature and the extubation practices adopted in the hospital's ICUs, based on analysis of institutional documents; proposal of an institutional extubation protocol based on the verified results. Results: Evidence suggests that factors such as a positive fluid balance, the presence of abundant secretions, advanced age, and compromised nutritional status increase the risk of extubation failure. Studies show that structured and standardized protocols, including functional testing and multidisciplinary management, increase the extubation success rate, especially in surgical and neurocritical patients. Corticosteroid prophylaxis, primarily dexamethasone and methylprednisolone, has been shown to reduce post-extubation complications. Furthermore, early extubation, when clinically feasible, is associated with better outcomes. These findings supported the proposal of an institutional protocol to standardize criteria, procedures, and care for extubation in ICUs. Conclusion: Based on the study, it is possible to conclude that there are significant variations and gaps in extubation practices across the hospital's ICUs, which reinforces the need for a standardized institutional protocol. The literature review highlighted evidence-based criteria and practices that can be adapted to local circumstances, and the analysis of available resources demonstrated the feasibility of implementing a unified protocol that promotes greater safety, uniformity, and quality in the care of critically ill patients.

Notifications of Salmonella Strathcona infections increased in Europe in 2023 prompting a multi-country outbreak investigation. We aimed to describe the epidemiology of S. Strathcona infections in 17 European countries 2011–2024, investigate the genetic relatedness of S. Strathcona isolates and identify the vehicle. Cases were persons residing in the study area and with a laboratory-confirmed S. Strathcona infection 2011–2024. Confirmed cases had a S. Strathcona isolate clustering with the outbreak reference strain in core genome multilocus sequence typing (cgMLST) within 7 allelic differences (AD) and possible cases within 8–13 AD. Probable cases had an epidemiological link to a confirmed case and non-outbreak cases had an isolate > 13 AD from the outbreak reference strain. Since 2011, 662 S. Strathcona infections have been identified: 469 confirmed, 161 probable, 13 possible and 19 non-outbreak cases. Median age of the cases was 34 years (IQR: 19–58 years) and 306 (47.5%) were notified in 2023–2024. Most sequenced isolates (469/496; 94.5%) were highly genetically related (≤ 7 AD) over time and across countries, compatible with a common source. Epidemiological and traceback investigations identified small tomatoes from Sicily as the suspect food vehicle. Stringent control measures at the source are needed to stop the contamination and prevent future cases.

When searching for effective public health interventions across Europe, professionals often face a confusing landscape: some countries promote “good”, others “best”, and others still “promising” practices - often referring to similar concepts. Likewise, widely used terms such as evidence and criteria differ significantly in meaning and application across national portals. This lack of conceptual and structural alignment complicates efforts to compare, access, and use best practices strategically across countries. This presentation addresses these challenges by exploring two interlinked approaches aimed at increasing the visibility, comparability, and political relevance of best practice portals in Europe. Elke Hackländer (BIÖG) introduces a pilot initiative within the Joint Action PreventNCD to create a web-based “portal of portals.” This tool will provide structured access to comparable information from national best practice portals. Based on expert dialogue and consultations, uniform comparison criteria are being developed to enable mutual learning, increase transparency, and support evidence-informed decision-making. A pretest survey was conducted to refine these criteria and inform the repository structure. Katarzyna Lewtak (PZH-PIB, Poland) presents complementary efforts undertaken during the Polish EU Presidency to increase the political visibility and uptake of best practices in public health. These efforts focus on translating identified best practices into actionable knowledge for policy development at the national and EU levels. Together, both contributions demonstrate how strategic alignment and stronger visibility mechanisms can foster equity-oriented, evidence-informed health promotion across Europe.

• Tree exposure dominates forest responses to drought at the local scale. • Locations with low water availability show weak drought resistance. • Dominant hydrological factors in forest NDWI vary greatly due to Switzerland's complex topography. Projected increases in drought frequency and strength in Central Europe in the next two decades due to anthropogenic climate change pose challenges for European temperate forests. Understanding the correlation between drought stress, local conditions, and forest responses is crucial for effective forest management and climate mitigation measures. We examine how local water dynamics determine the response of Swiss forests during the European drought in 2018. We particularly investigate how increased atmospheric water demand, reduced soil water availability, and increased exposure of forests to potentially harsh abiotic conditions at the edge of the forest affect forest health. We used Sentinel-2 data to calculate the normalized difference water index (NDWI) as proxy for forest health. Weather data, data from a process based hydrological model, a digital elevation model, and airborne LiDAR data were used to assess hydrological drivers. Our analysis revealed that forest exposure and water availability were more important than atmospheric water demand in explaining forest drought resistance. Regions with more limited water availability (47 % of Switzerland) had systematically higher proportions of forest areas that exhibited weak drought resistance (R² = 0.56 for moderate NDWI decrease and 0.55 for severe NDWI decrease). Forest exposure (i.e. the degree to which a forest patch stands out from the surroundings) could best explain weak drought resistance, with strong statistical relationships (R² = 0.69, R² = 0.50). Finally, atmospheric water demand had only a moderate effect on weak drought resistance (R² = 0.45 and 0.27). Our findings highlight the complex interplay of local water dynamics and forest responses to drought, while providing insights on how forest structure and exposure conditions at local scales affect responses and need to be considered when examining forest health under changing climatic conditions.

Sexual behavior is heterogeneous and dynamic. Characterization of such complexity constitutes evidence for public health authorities and caregivers concerned with the framing of sexual health messages aimed at specific subgroups. We developed a machine-learning-based methodology for inference and characterization of such subgroups from longitudinal data on men who have sex with men (MSM) attending individual sexual health counseling sessions. Because longitudinal data take time to record, we assessed the ability of first visit data to predict subgroups' membership. Our methodology comprised two main steps: (1) Hierarchical clustering to group 2349 HIV-negative MSM based on their self-reported longitudinal sexual behavior during visits to Swiss sexual health counseling centers between November 2016 and April 2019; and (2) Random forest-based classification to predict subgroup membership from first visit data. We found six subgroups with significant differences in behavioral trends, most of which sharply deviated from the overall trends. Two subgroups, which contained 37% of the study population, accounted for over 70% of the overall increases in condomless anal intercourse with non-steady partners, group sex, and having more than five anal intercourse partners. Subgroup-specific trends in online-dating and group sex were heterogeneous with opposing trends across subgroups. Data from first visits predicted trends of sexual behavior with accuracy ranging from 64 to 86%. This study evidenced specific sexual behavioral subgroups that might benefit from customized sexual health messages, demonstrated that first visit registries could predict subgroups, and contributes an algorithmic alternative for establishing subgroups relevant to inform customized sexual health messages that capture sexual behavioral diversity.

This research addresses the issue of suicide and attempted suicide, which have a significant impact on global premature mortality and disability. Particularly noteworthy is the prevalence among adolescents, in whom suicide ranks among the top four causes of death according to the World Health Organization (WHO). In Switzerland, suicide has remained the leading cause of death in individuals under 50 since 1990. At the same time, the burden of attempted suicides remains poorly understood. Although the legality of assisted suicide in Switzerland influences the overall suicide data, this analysis focuses solely on non-assisted suicides, as they are relevant for accurately assessing the burden of disease of suicide and attempted suicide. Amid challenges posed by limited reporting infrastructure, this analysis aims to contribute to the existing literature by investigating the cumulative impact of non-assisted suicide and attempted suicide on the population living in Switzerland. Pre-existing data from 2009 to 2021 were collected and analysed, drawing from a variety of sources including official health records from the federal offices of statistics and public health, surveys and retrospective studies. From this data, years of life lost (YLLs), years lived with disability (YLDs) and disability-adjusted life-years (DALYs) were calculated in order to estimate the burden of disease. Sensitivity analyses were conducted to determine the robustness of the data and the effect of variables (suicide attempt incidence, sex distribution, disability weight, average duration) on the DALYs. The analysis of the data spanning from 2009 to 2021 revealed a decrease in suicide. The present study determined that, in 2021, 32,771 DALYs were attributable to non-assisted suicide and attempted suicide and 6.4% of all years of life lost (n = 30,516) were attributable to suicide, not including assisted suicide. Using a reference incidence of 33,000 attempted suicides per year in Switzerland, the morbidity associated with attempted suicides was 2255 YLDs (range: 552-6557 YLDs). Further analysis of the data highlighted a stark sex gap in the prevalence of non-assisted suicide: male suicides account for around 2% of all male deaths, whereas female suicides account for approximately 0.8% of all female deaths. Sensitivity analyses found that incidence and sex distribution of attempted suicide were the most impactful factors, while disability weights and average duration of disability had little impact on the variation in YLD estimates. In conclusion, this study provides a detailed analysis of the burden of non-assisted suicide and attempted suicide in Switzerland. With non-assisted suicide accounting for 6.4% of all years of life lost and 30% of deaths in people aged 20-24 in Switzerland in 2021, it emerges that suicide contributes significantly to the country's overall disease burden, particularly in terms of years of life lost. The stark sex disparity in suicide rates further underscores the need for sex-sensitive approaches. These insights can help guide policy-making and the allocation of resources towards reducing the incidence and impact of suicide and attempted suicide, both in Switzerland and in broader international contexts where similar patterns prevail.

As coronavirus disease 2019 (COVID-19) is integrated into existing infectious disease control programs, it is important to understand the comparative clinical impact of COVID-19 and other respiratory diseases. We conducted a retrospective cohort study of patients with symptomatic healthcare-associated COVID-19 or influenza reported to the nationwide, hospital-based surveillance system in Switzerland. Included patients were adults (aged ≥18 years) hospitalized for ≥3 days in tertiary care and large regional hospitals. Patients had COVID-19 symptoms and a real-time polymerase chain reaction-confirmed severe acute respiratory syndrome coronavirus 2 infection ≥3 days after hospital admission between 1 February 2022 and 30 April 2023, or influenza symptoms and a real-time polymerase chain reaction-confirmed influenza A or B infection ≥3 days after hospital admission between 1 November 2018 and 30 April 2023. Primary and secondary outcomes were 30-day in-hospital mortality and admission to intensive care unit, respectively. Cox regression (Fine-Gray model) was used to account for time dependency and competing events, with inverse probability weighting to adjust for confounding. We included 2901 patients with symptomatic, healthcare-associated COVID-19 (Omicron) and 868 patients with symptomatic, healthcare-associated influenza from 9 hospitals. We found a similar case fatality ratio between healthcare-associated COVID-19 (Omicron) (6.2%) and healthcare-associated influenza (6.1%) patients; after adjustment, patients had a comparable subdistribution hazard ratio for 30-day in-hospital mortality (0.91; 95% confidence interval, .67-1.24). A similar proportion of patients were admitted to the intensive care unit (2.4% COVID-19; 2.6% influenza). COVID-19 and influenza continue to cause severe disease among hospitalized patients. Our results suggest that in-hospital mortality risk of healthcare-associated COVID-19 (Omicron) and healthcare-associated influenza are comparable.