Incidence of alpine skiing and snowboarding injuries.

BACKGROUND: The incidence of injuries on alpine ski slopes have been assessed using various methods. A decline in injury rate has been observed throughout the literature; however, the actual incidence remains unclear. The purpose of this study was therefore to evaluate the incidence of skiing and snowboarding injuries using large-sample data from an entire geographic state. METHODS: Data on alpine injuries over the course of five winter seasons between 2017 and 2022 were prospectively collected from the emergency service dispatch center of Tyrol (Austria). The incidence of injuries was assessed in relation to the number of skier days, which was obtained from the chamber of commerce. RESULTS: A total of 43,283 cases were identified, and a total of 98.1 Mio skier days were registered during the inclusion period of our study, resulting in an overall incidence of 0.44 injuries per 1,000 skier days. This is significantly less than reported from previous studies. From 2017/18 to 2021/22 there was a slight increase in injuries per 1000 skier days with an exception only for the COVID-19 related season 2020/21. CONCLUSION: Our study showed a significant reduction in the incidence of alpine skiing and snowboarding injuries in comparison with previous studies and should be considered a benchmark for future studies. Long-term studies on the efficacy of safety gear, as well as the influence of ski patrol and air-borne rescues on patient outcome are warranted.

Emergency Service Assistance for Injuries on Alpine Ski Slopes: A Cross-Sectional Study.

OBJECTIVES: Injuries on alpine ski slopes have been described in cohorts of a reasonable sample size, but constant improvements in safety gear, increased use of airborne rescue, and safety measures during the coronavirus disease 2019 (COVID-19) pandemic mandate re-evaluation. Therefore, the purpose of this study was to evaluate skiing and snowboarding injuries, effectiveness of airborne rescue, and impact of the COVID-19 pandemic on a large sample size. METHODS: Data on alpine injuries were prospectively collected from the state emergency services dispatch center in the state of Tyrol (Austria). A total of 10,143 patients were identified, with an average age of 33.5 years (SD = 20.36). The ski patrol was involved in 8,606 cases (84.9%) and some patients (n = 1,536; 15.1%) required helicopter rescue. RESULTS: A total of 10,143 patients were identified from the dataset of the emergency dispatch center. The most frequently injured region was the knee (30.2%), and it was followed by the shoulder (12.9%), the lower leg (9.5%), and the head/skull (9.5%). CONCLUSION: The present findings indicate that the most frequent site of injuries on alpine slopes is the knee, and life-threatening injuries are rare. Airborne rescue is very time-effective, however clinical studies with patient follow-up should be emphasized to determine the impact of airborne rescue on patient outcome. The present findings indicate that the duration of all rescue operations has been prolonged as a result of the introduction of safety measures during the COVID-19 pandemic.

Assessing real-world vaccine effectiveness against severe forms of SARS-CoV-2 infection: an observational study from routine surveillance data in Switzerland.

BACKGROUND: In Switzerland, SARS-CoV-2 vaccination campaigns started in early 2021. Vaccine coverage reached 65% of the population in December 2021, mostly with mRNA vaccines from Moderna and Pfizer-BioNtech. Simultaneously, the proportion of vaccinated among COVID-19-related hospitalisations and deaths rose, creating some confusion in the general population. We aimed to assess vaccine effectiveness against severe forms of SARS-CoV-2 infection using routine surveillance data on the vaccination status of COVID-19-related hospitalisations and deaths, and data on vaccine coverage in Switzerland. METHODS: We considered all routine surveillance data on COVID-19-related hospitalisations and deaths received at the Swiss Federal Office of Public Health from 1 July to 1 December 2021. We estimated the relative risk of COVID-19-related hospitalisation or death for not fully vaccinated compared with fully vaccinated individuals, adjusted for the dynamics of vaccine coverage over time, by age and location. We stratified the analysis by age group and by calendar month. We assessed variations in the relative risk of hospitalisation associated with the time since vaccination. RESULTS: We included a total of 5948 COVID-19-related hospitalisations of which 1245 (21%) were fully vaccinated patients, and a total of 739 deaths of which 259 (35%) were fully vaccinated. We found that the relative risk of COVID-19 related hospitalisation was 12.5 (95% confidence interval [CI] 11.7-13.4) times higher for not fully vaccinated than for fully vaccinated individuals. This translates into a vaccine effectiveness against hospitalisation of 92.0% (95% CI 91.4-92.5%). Vaccine effectiveness against death was estimated to be 90.3% (95% CI 88.6-91.8%). Effectiveness appeared to be comparatively lower in age groups over 70 and during the months of October and November 2021. We also found evidence of a decrease in vaccine effectiveness against hospitalisation for individuals vaccinated for 25 weeks or more, but this decrease appeared only in age groups below 70. CONCLUSIONS: The observed proportions of vaccinated among COVD-19-related hospitalisations and deaths in Switzerland were compatible with a high effectiveness of mRNA vaccines from Moderna and Pfizer-BioNtech against hospitalisation and death in all age groups. Effectiveness appears comparatively lower in older age groups, suggesting the importance of booster vaccinations. We found inconclusive evidence that vaccine effectiveness wanes over time. Repeated analyses will be able to better assess waning and the effect of boosters.

Using contact data to model the impact of contact tracing and physical distancing to control the SARS-CoV-2 outbreak in Kenya [version 1;peer review: awaiting peer review]

Background: Across the African continent, other than South Africa, COVID-19 cases have remained relatively low. Nevertheless, in Kenya, despite early implementation of containment measures and restrictions, cases have consistently been increasing. Contact tracing forms one of the key strategies in Kenya, but may become infeasible as the caseload grows. Here we explore different contact tracing strategies by distinguishing between household and non-household contacts and how these may be combined with other non-pharmaceutical interventions. Methods: We extend a previously developed branching process model for contact tracing to include realistic contact data from Kenya. Using the contact data, we generate a synthetic population of individuals and their contacts categorised by age and household membership. We simulate the initial spread of SARS-CoV-2 through this population and look at the effectiveness of a number of non-pharmaceutical interventions with a particular focus on different contact tracing strategies and the potential effort involved in these. Results: General physical distancing and avoiding large group gatherings combined with contact tracing, where all contacts are isolated immediately, can be effective in slowing down the outbreak, but were, under our base assumptions, not enough to control it without implementing extreme stay at home policies. Under optimistic assumptions with a highly overdispersed R0 and a short delay from symptom onset to isolation, control was possible with less stringent physical distancing and by isolating household contacts only. Conclusions: Without strong physical distancing measures, controlling the spread of SARS-CoV-2 is difficult. With limited resources, physical distancing combined with the isolation of households of detected cases can form a moderately effective strategy, and control is possible under optimistic assumptions. More data are needed to understand transmission in Kenya, in particular by studying the settings that lead to larger transmission events, which may allow for more targeted responses, and collection of representative age-related contact data.

The negative impact of the COVID-19 lockdown on pain and physical function in patients with end-stage hip or knee osteoarthritis.

PURPOSE: The purpose of this study was to evaluate pain, functional impairment, mental health, and daily activity in patients with end-stage hip and knee osteoarthritis (OA) during the COVID-19 lockdown. METHODS: The study included 63 patients, with hip or knee OA, who had been scheduled for arthroplasty that was postponed because of COVID-19. Patients were evaluated by telephone interviews during the first week after lockdown, in the fourth week, and again at the end of the lockdown. Patients rated their pain level on the basis of a visual analog scale (VAS) and completed WOMAC, SF-12 and Tegner activity scale (TAS) questionnaires. RESULTS: VAS and WOMAC scores increased significantly during lockdown, while physical activity significantly decreased. At the final evaluation, VAS and WOMAC showed a significant negative correlation with TAS. The SF-12 subscale scores showed a significant decrease of the physical component during the lockdown, while the mental component remained largely unchanged. Patients with knee OA showed a faster progress of pain compared to those with hip OA. 50 patients (79%) stated they wished to have arthroplasty as soon as possible. CONCLUSION: The COVID-19 lockdown had a significant impact on pain, joint function, physical function, and physical activity in patients with end-stage hip and knee OA. LEVEL OF EVIDENCE: II (Prospective cohort study).

Tooling-up for infectious disease transmission modelling.

In this introduction to the Special Issue on methods for modelling of infectious disease epidemiology we provide a commentary and overview of the field. We suggest that the field has been through three revolutions that have focussed on specific methodological developments; disease dynamics and heterogeneity, advanced computing and inference, and complexity and application to the real-world. Infectious disease dynamics and heterogeneity dominated until the 1980s where the use of analytical models illustrated fundamental concepts such as herd immunity. The second revolution embraced the integration of data with models and the increased use of computing. From the turn of the century an emergence of novel datasets enabled improved modelling of real-world complexity. The emergence of more complex data that reflect the real-world heterogeneities in transmission resulted in the development of improved inference methods such as particle filtering. Each of these three revolutions have always kept the understanding of infectious disease spread as its motivation but have been developed through the use of new techniques, tools and the availability of data. We conclude by providing a commentary on what the next revoluition in infectious disease modelling may be.