The Science of the total environment
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Sci. Total Environ. · Jun 2021
ReviewWhy airborne transmission hasn't been conclusive in case of COVID-19? An atmospheric science perspective.
Airborne transmission is one of the routes for the spread of COVID-19 which is caused by inhalation of smaller droplets1 containing SARS-CoV-2 (i.e., either virus-laden particulate matter: PM and/or droplet nuclei) in an indoor environment. Notably, a significant fraction of the small droplets, along with respiratory droplets, is produced by both symptomatic and asymptomatic individuals during expiratory events such as breathing, sneezing, coughing and speaking. When these small droplets are exposed to the ambient environment, they may interact with PM and may remain suspended in the atmosphere even for several hours. ⋯ For example, these small droplets containing SARS-CoV-2 might also physically combine with or attach to pre-existing PM so that their behaviour and fate may be governed by PM composition. Thus, the measurement of their infectivity and viability is highly uncertain due to a lack of robust sampling system to separately collect virions in the atmosphere. We believe that the present review will help to minimize the gap in our understanding of the current pandemic and develop a robust epidemiological method for mortality assessment.
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Sci. Total Environ. · Jun 2021
Impact of climate and population changes on the increasing exposure to summertime compound hot extremes.
Attributing the changes in the population exposure to global compound hot extremes, which combine daytime-nighttime hot extremes with more severe impacts, is essential for climate change adaptation. Based on daily temperature data from the Coupled Model Intercomparison Project phase 6 (CMIP6) and population data, we estimate the changes in population exposure for two future periods under three scenarios of emission and socio-economic development at global and continental scales, and assess the contributions from climate and population changes. We find that the spatial patterns of exposure to compound hot extremes are similar for different periods and scenarios, and regions with high exposure are mainly located over East Asia, South Asia, Europe, and parts of eastern USA and Africa. ⋯ Early (SSP1-2.6) and no (SSP5-8.5) actions of mitigation would relieve and aggravate the increase rate, respectively. For about 78%-87% of the global land areas, the changes in exposure are mainly caused by climate change (accounting for >69%), followed by the interaction effect (accounting for ~29%) that refers to synergistic changes in climate and population. In parts of mid- to high-latitude regions, the exposure is smaller than expected due to opposite effects of climate change and population change.
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Sci. Total Environ. · May 2021
High prevalence of SARS-CoV-2 infection among food delivery riders. A case study from Quito, Ecuador.
COVID-19 pandemic has posed an unprecedented pressure on health systems and economies worldwide. Delivery services have grown as an alternative source of revenue for many people. Consumers generally perceive that delivery services are safer than going into a restaurant, because they reduce exposure to other people and their risk of SARS-CoV-2 contagion. There are no studies analyzing viral load or the burden of COID-19 within this population. This study aims to describe the presence of SARS-CoV-2 among food delivery riders in the city of Quito, Ecuador. ⋯ The self-employed food delivery riders have a high incidence rate of SARS-CoV-2 infection in relation to the national average. It is important to point out that this is the first study of its kind in Latin-American and probably one of the very few in the world. The results emphasize the need for policy makers to look at the pandemic from as many population's sub-groups as possible. Delivery riders are a highly moving population that offer their services to a wide range of clients, including vulnerable populations such as the elderly or those less likely to leave their house for basic needs stoking.
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Sci. Total Environ. · May 2021
Surveillance of SARS-CoV-2 spread using wastewater-based epidemiology: Comprehensive study.
SARS-CoV-2 pandemic is having a devastating effect on human lives. Recent reports have shown that majority of the individuals recovered from COVID-19 have serious health complications, which is going to be a huge economic burden globally. Given the wide-spread transmission of SARS-CoV-2 it is almost impossible to test every individual in densely populated countries. ⋯ Interestingly, inlet samples of STPs were positive for SARS-CoV-2, while the outlets were negative, which indicates that the standard sewage treatment methods are efficient in eliminating the SARS-CoV-2 viral particles. Based on the detected viral gene copies per litre and viral particle shedding per individual, the total number of individuals exposed to SARS-CoV-2 was estimated. Through this study we suggest that sewage-based surveillance is an effective approach to study the infection dynamics, which helps in efficient management of the SARS-CoV-2 spread.