Interruption of cancer screening services due to COVID-19 pandemic: lessons from previous disasters

Purpose: To review the scientific literature seeking lessons for the COVID-19 era that could be learned from previous health services interruptions that affected the delivery of cancer screening services. Methods: A systematic search was conducted up to April 17, 2020, with no restrictions on language or dates and resulted in 385 articles. Two researchers independently assessed the list and discussed any disagreements. Once a consensus was achieved for each paper, those selected were included in the review. Results: Eleven articles were included. Three studies were based in Japan, two in the United States, one in South Korea, one in Denmark, and the remaining four offered a global perspective on interruptions in health services due to natural or human-caused disasters. No articles covered an interruption due to a pandemic. The main themes identified in the reviewed studies were coordination, communication, resource availability and patient follow-up. Conclusion: Lessons learned applied to the context of COVID-19 are that coordination involving partners across the health sector is essential to optimize resources and resume services, making them more resilient while preparing for future interruptions. Communication with the general population about how COVID-19 has affected cancer screening, measures taken to mitigate it and safely re-establish screening services is recommended. Use of mobile health systems to reach patients who are not accessing services and the application of resource-stratified guidelines are important considerations. More research is needed to explore best strategies for suspending, resuming and sustaining cancer screening programs, and preparedness for future disruptions, adapted to diverse health care systems

High-Temperature Stable Operation of Nanoribbon Field-Effect Transistors

We experimentally demonstrated that nanoribbon field-effect transistors can be used for stable high-temperature applications. The on-current level of the nanoribbon FETs decreases at elevated temperatures due to the degradation of the electron mobility. We propose two methods of compensating for the variation of the current level with the temperature in the range of 25–150°C, involving the application of a suitable (1) positive or (2) negative substrate bias. These two methods were compared by two-dimensional numerical simulations. Although both approaches show constant on-state current saturation characteristics over the proposed temperature range, the latter shows an improvement in the off-state control of up to five orders of magnitude (−5.2 × 10−6)

Inference of type-specific HPV transmissibility, progression and clearance rates: a mathematical modelling approach.

Quantifying rates governing the clearance of Human Papillomavirus (HPV) and its progression to clinical disease, together with viral transmissibility and the duration of naturally-acquired immunity, is essential in estimating the impact of vaccination programmes and screening or testing regimes. However, the complex natural history of HPV makes this difficult. We infer the viral transmissibility, rate of waning natural immunity and rates of progression and clearance of infection of 13 high-risk and 2 non-oncogenic HPV types, making use of a number of rich datasets from Sweden. Estimates of viral transmissibility, clearance of initial infection and waning immunity were derived in a Bayesian framework by fitting a susceptible-infectious-recovered-susceptible (SIRS) transmission model to age- and type-specific HPV prevalence data from both a cross-sectional study and a randomised controlled trial (RCT) of primary HPV screening. The models fitted well, but over-estimated the prevalence of four high-risk types with respect to the data. Three of these types (HPV-33, -35 and -58) are among the most closely related phylogenetically to the most prevalent HPV-16. The fourth (HPV-45) is the most closely related to HPV-18; the second most prevalent type. We suggest that this may be an indicator of cross-immunity. Rates of progression and clearance of clinical lesions were additionally estimated from longitudinal data gathered as part of the same RCT. Our estimates of progression and clearance rates are consistent with the findings of survival analysis studies and we extend the literature by estimating progression and clearance rates for non-16 and non-18 high-risk types. We anticipate that such type-specific estimates will be useful in the parameterisation of further models and in developing our understanding of HPV natural history

Differences in risk for SARS-CoV-2 infection among healthcare workers

Abstract Healthcare workers (HCWs) are a risk group for SARS-CoV-2 infection, but which healthcare work that conveys risk and to what extent such risk can be prevented is not clear. Starting on April 24th, 2020, all employees at work (n = 15,300) at the Karolinska University Hospital, Stockholm, Sweden were invited and 92% consented to participate in a SARS-CoV-2 cohort study. Complete SARS-CoV-2 serology was available for n = 12,928 employees and seroprevalences were analyzed by age, sex, profession, patient contact, and hospital department. Relative risks were estimated to examine the association between type of hospital department as a proxy for different working environment exposure and risk for seropositivity, adjusting for age, sex, sampling week, and profession. Wards that were primarily responsible for COVID-19 patients were at increased risk (adjusted OR 1.95 (95% CI 1.65–2.32) with the notable exception of the infectious diseases and intensive care units (adjusted OR 0.86 (95% CI 0.66–1.13)), that were not at increased risk despite being highly exposed. Several units with similar types of work varied greatly in seroprevalences. Among the professions examined, nurse assistants had the highest risk (adjusted OR 1.62 (95% CI 1.38–1.90)). Although healthcare workers, in particular nurse assistants, who attend to COVID-19 patients are a risk group for SARS-CoV-2 infection, several units caring for COVID-19 patients had no excess risk. Large variations in seroprevalences among similar units suggest that healthcare work-related risk of SARS-CoV-2 infection may be preventable

Resource selection by sympatric free-ranging dairy cattle and brown bears

Livestock depredation is an important factor that contributes to low public acceptance of large carnivores, and is often used as an incentive to reduce large carnivore populations. In central Sweden, brown bears (Ursus arctos) coexist with a traditional cattle husbandry system that allows daytime free-ranging of dairy cattle. Despite a growing brown bear population, depredation on cattle remained stable during the last decade, and among the lowest rates reported worldwide. Nevertheless, major stakeholders argue for a substantial reduction in brown bear numbers, among other reasons, to safeguard this traditional husbandry system. Based on satellite tracking data, we assessed and correlated the resource selection of nine brown bears that were sympatric with six daytime free-ranging cattle herds during the free-ranging season (June-August) in 2008. We found a significant and negative relationship between resource selection of brown bears and free ranging cattle during the study period, mainly because of inverse relationships between the species towards vegetation density and human-related infrastructure, such as forest roads, buildings, and settlements. We predict that the probability of an encounter between these species, given that there is no directed predation, is highest in dense vegetation patches close to these human habitation-related variables. Because of the low reported depredation rates and the apparent habitat segregation between the species, our results provide no support for the argument to reduce brown bear numbers to safeguard this traditional cattle herding system