The impact of COVID-19 vaccines on the Case Fatality Rate: The importance of monitoring breakthrough infections

Objectives: Test the behavior of the case fatality rate in a mixed population of vaccinated and unvaccinated individuals by illustrating the role of both the effectiveness of vaccines in preventing deaths and the detection of infections among both the vaccinated (breakthrough infections) and unvaccinated individuals. Methods: We simulate three hypothetical case fatality rate scenarios that result from a different combination of vaccine effectiveness in preventing deaths and the efforts in detecting infections among both the vaccinated and unvaccinated individuals. Results: In the presence of vaccines, the case fatality rate depends not only on the effectiveness of vaccines in preventing deaths, but also on the detection of breakthrough infections. As a result, a decline in the case fatality rate may not imply that vaccines are being effective in reducing deaths. Likewise, a constant case fatality rate can still mean that vaccines are effective in reducing deaths. Conclusions: Unless vaccinated people are also tested, the case fatality rate loses its meaning in tracking the pandemic. This shows that unless efforts are directed at detecting breakthrough infections, it is hard to disentangle the effect of vaccines in reducing deaths from the probability of detecting infections on the case fatality rate

Improving the light collection efficiency of silicon photomultipliers through the use of metalenses

Metalenses are optical devices that implement nanostructures as phase shifters to focus incident light. Their compactness and simple fabrication make them a potential cost-effective solution for increasing light collection efficiency in particle detectors with limited photosensitive area coverage. Here we report on the characterization and performance of metalenses in increasing the light collection efficiency of silicon photomultipliers (SiPM) of various sizes using an LED of 630 nm, and find a six to seven-fold increase in signal for a 1.3×1.3 mm² SiPM when coupled with a 10-mm-diameter metalens manufactured using deep ultraviolet stepper lithography. Such improvements could be valuable for future generations of particle detectors, particularly those employed in rare-event searches such as dark matter and neutrinoless double beta decay

A demographic perspective on human wellbeing: Concepts, measurement and population heterogeneity

This introduction to the 2021 special issue of the Vienna Yearbook of PopulationResearch explores demographic perspectives on human wellbeing across time andspace. While the idea of relating demographic parameters to wellbeing has beenaround for a while, a more concrete research agenda on this topic has only recentlygained momentum. Reviewing the research presented in this volume, we show howexisting theoretical concepts and methodological tools in demography can be usedto make substantial advances in the study of wellbeing. We also touch upon themany challenges researchers face in defining and measuring wellbeing, with themost important debate being about whether the focus should be on objective orsubjective measures. The studies discussed here define wellbeing as health andmortality; as income, education or other resources; as happiness or life satisfaction;or as a combination thereof. They cover wellbeing in historical and contemporarypopulations in high- and low-income countries, and also point out important barriersto research on wellbeing, including the lack of good quality data in many regions.Finally, we highlight the value of considering population heterogeneities when studying wellbeing in order to identify population subgroups who are likely to fallbehind, which can have important policy implications

An indirect method to monitor the fraction of people ever infected with COVID-19: An application to the United States

The number of COVID-19 infections is key for accurately monitoring the pandemics. However, due to differential testing policies, asymptomatic individuals and limited large-scale testing availability, it is challenging to detect all cases. Seroprevalence studies aim to address this gap by retrospectively assessing the number of infections, but they can be expensive and time-intensive, limiting their use to specific population subgroups. In this paper, we propose a complementary approach that combines estimated (1) infection fatality rates (IFR) using a Bayesian melding SEIR model with (2) reported case-fatality rates (CFR) in order to indirectly estimate the fraction of people ever infected (from the total population) and detected (from the ever infected). We apply the technique to the U.S. due to their remarkable regional diversity and because they count with almost a quarter of all global confirmed cases and deaths. We obtain that the IFR varies from 1.25% (0.39–2.16%, 90% CI) in Florida, the most aged population, to 0.69% in Utah (0.21–1.30%, 90% CI), the youngest population. By September 8, 2020, we estimate that at least five states have already a fraction of people ever infected between 10% and 20% (New Jersey, New York, Massachussets, Connecticut, and District of Columbia). The state with the highest estimated fraction of people ever infected is New Jersey with 17.3% (10.0, 55.8, 90% CI). Moreover, our results indicate that with a probability of 90 percent the fraction of detected people among the ever infected since the beginning of the epidemic has been less than 50% in 15 out of the 20 states analyzed in this paper. Our approach can be a valuable tool that complements seroprevalence studies and indicates how efficient have testing policies been since the beginning of the outbreak

People and plant: Learning with Adi community on ethnomedicinal practices and conservation in Arunachal Pradesh, India

74-82Local plant species have been in use in variety of ethnomedicinal practices from the time immemorial among the people of various communities for treating various human diseases. This paper reports about the plant species used by Adi community in curing various human diseases and ailments. A study was conducted during 2008-2009 and further refined in succeeding years with the 12 purposively selected traditional knowledge holders (TKHs) of Adi tribe of East Siang district, Arunachal Pradesh, India. Data were collected using combined approaches of personal interview, participant observations and transect walks. It was observed that with Shannon-Weaver diversity index 2.73, there were 39 local plant species belonging to 25 plant families and used as ethnomedicinal practices by the TKHs. Most of the species (17) were used by Adi TKHs with their green leaf parts followed by root and fruits (5 each) to develop ethnomedicinal formulations. Out of these, several species namely Leucas aspera (Willd.) Link.; Plumeria rubra L.; Catharanthus roseus (L.) G. Don; Solanum torvum Swartz; Solanum khasianum C.B. Clarke; Oroxylum indicum (L.) Benth.ex Kurze; and Tinospora cordifolia (Thunb.) Miers) were found in use by Adis against asthma, bronchitis, cough, sinusitis, diabetes, malaria, typhoid and jaundice. The Adi TKHs maintain a rich cultural ethics, govern by their own world-view in continuing ethnomedicinal practices, and harvesting the species from various land use systems with the aim to sustain biodiversity and associated practices. The key findings indicated that, plant species used as ethnomedicines for some of the diseases and ailments by the Adi TKHs, can be undertaken for the long-term trial to find some natural remedies against few human diseases, including search of immune enhancer against COVID-19, provided TKHs of Adi community are partnered in ethically and culturally appropriate manner.&nbsp