The intake of selenium varies worldwide, and China is known to be one of the most severely selenium deficient countries in the world, with a wide range of selenium level that differs from the lowest to the highest in the world. Considering that fatality rate of COVID-19 also varied across different afflicted regions in China [19], we wondered if there might be a relationship between disease severity of COVID-19 and selenium level [20]. Here we applied an ecological study to evaluate the association between COVID-19 related fatality and the selenium content in crops and topsoil at the population level in China.
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This study was approved by the institutional review board of the Beijing Institute of Microbiology and Epidemiology (Beijing, China). All data were collected from publicly available sources. Data were de-identified, and informed consent was waived.
In this study, a statistically significant ecological association between CFR of COVID-19 and selenium deficiency, measured from both crops and topsoil, was found in the mainland of China. In comparison with previous study that reported a significant association between cure rate and background selenium status in cities outside Hubei [20], our study had the advantage that most recent updated data were used for analysis. The current data on intake of selenium were obtained based on the most extensive investigation of selenium content in crops that covered all 2922 counties, and 4095 investigation sites of selenium content in topsoil. The highly credible fatality data in China was accessible as the epidemic has been largely brought to an end, with highly sporadic new cases and no new death reported for a long duration, also giving an optimal opportunity to make fatality related analysis. A current clinical study performed in German verified the association between Se and clinical outcomes of COVID-19, where a pronounced deficit in total serum Se was displayed in SARS-COV-2 infected cases, with Se deficiency more severe in the non-survivors as compared with survivors of COVID-19 [28].
On the other hand, selenium might affect the blood coagulation and thrombosis formation in the form of sodium selenite that could decrease thromboxane A2 (TXA2) formation that plays a key role in blood platelet activation and aggregation [35, 36]. It is well documented from a number of hemorrhagic fever viruses, including Hantavirus and Ebola virus that selenium might be involved in the hemorrhagic manifestations by affecting the prostacyclin/TXA2 ratio and thus blood clotting [37]. This mechanism could support the association between selenium deficiency and more coagulation dysfunction in COVID-19, i.e., thrombocytopenia, prolonged APTT and PT, as well as increased DIC development, according to the current findings. All these indicators are critical factors in determining the disease severity in COVID-19 [38], thus providing potential mechanism how selenium could be involved in this process. A most recent study, based on a linear association between selenium deficiency with hypoglycemia in healthy adults, also supported the role of adequate Se supply for glucose homeostasis in human subjects [39]. This newly identified relationship may be of relevance for the course of severe complications in COVID-19 with mortality risk. Recognition of these mechanisms by which selenium might potentially benefit COVID-19 patients provides a rationale for selenium supplementation in SARS-CoV-2 infection. Existing data on the effect from daily selenium supplementation to treat viral infection, most notably with respect to HIV and influenza A virus infections, are heterogeneous [16]. In one clinical study, although selenium supplementation delayed CD4 decline in HIV-infected patients, no evidence of suppressing or reducing HIV viral load was seen [40]. Inconsistent results of benefits with routine multiple micronutrient supplementation in HIV infection was noticed from numerous clinical trials [41]. However, these findings should not be interpreted as a reason to deny micronutrient supplements for people with known specific deficiencies or with lower diet level under the recommended allowance. Particularly for the eldly, who had high odds of progressing into fatal COVID and were more likely to be with selenium deficiency, might gain some benefit from prophylactic micronutrition supplementation.
LQF and WL conceived and designed the study. HYZ and ARZ contributed to data collection. HL, QBL, LQF, HYZ, ARZ, XAZ, ZJZ, XGG, TLC and YY contributed to data analysis. LQF, LW, and HL contributed to the writing of the report. HYZ and ARZ contributed equally and share first authorship. The author(s) read and approved the final manuscript.
With the rapid evolution of the open education concept, researchers have shifted their focus from content-centred approaches, which focus on educational resources (creation, sharing, etc.), to more practice-centred ones that foster collaboration between learners and teachers for creating and sharing knowledge (Cronin, 2017). In other words, researchers and educators have shifted their focus from creating and publishing OER to practices that can be implemented using OER for education, referred to as Open Educational Practices (OEP). In line with these developments, this study focuses on OEP that could be used to provide active and engaging learning experiences for learners during this COVID-19 outbreak. To do so, OEP must be fully understood since, as noted by Cronin (2017), their scope is rapidly evolving, and researchers tend to focus on different OEP perspectives. Therefore, the next section aims to draw an OEP framework based on several reported OEP definitions in the literature. The authors will then refer to this framework when presenting guidelines about OEP application in education during the COVID-19 outbreak.
To better understand OEP, a comprehensive review was conducted about the reported OEP definitions in the literature, as shown in Table 1. Several keywords were then identified from each definition (see Table 1). Finally, based on these keywords, five conditions are identified and discussed below, which have been used to create the OEP framework of this study.
To conclude, because of the unexpected COVID-19 outbreak, the Chinese educational system is being reformed to maintain the learning process without having to be physically present in classes. This study first presents the education challenges during this emergency and then discusses the application of OER and OEP to overcome these challenges. Particularly, this study presents a generic OEP framework built on existing open practice definitions as well as guidelines for both teachers and learners related to the implementation of OEP for an engaging and active learning and teaching experience and for better learning outcomes. These guidelines are identified based on the challenges highlighted by several experts during two national seminars, organised to discuss online and open education during this COVID-19 outbreak, as well as on several challenges highlighted in the literature by international experts. Finally, this paper discusses urgent strategies that could be applied to support open and online education reform and puts forward some recommendations to foster the adoption of OER/OEP. Future research will focus on presenting a practical experience of using OEP for teaching during the COVID-19 outbreak as well as its impact on learning outcomes.
We dedicate this publication to the memory of all people in China and worldwide who died from the coronavirus (COVID-19) outbreak. We also thank all the participating Chinese government departments and national and international education specialists and professors for their support and constructive feedback during this study.
The virus can also persist on surfaces to varying durations and degrees of infectivity, although this is not believed to be the main route of transmission. [35] One study found that SARS-CoV-2 remained detectable for up to 72 hours on some surfaces despite decreasing infectivity over time. Notably, the study reported that no viable SARS-CoV-2 was measured after 4 hours on copper or after 24 hours on cardboard. [39]
Among 137 survivors of COVID-19, viral shedding based on testing of oropharyngeal samples ranged from 8 to 37 days, with a median of 20 days. [42] A different study found that repeated viral RNA tests using nasopharyngeal swabs were negative in 90% of cases among 21 patients with mild illness, whereas results were positive for longer durations in patients with severe COVID-19. [43] In an evaluation of patients recovering from severe COVID-19, Zhou and colleagues found a median shedding duration of 31 days (range, 18-48 days). [44] These studies have all used PCR detection as a proxy for viral shedding. The Korean CDC, investigating a cohort of patients who had prolonged PCR positivity, determined that infectious virus was not present. [45] These findings were incorporated into the CDC guidance on the duration of isolation following COVID-19 infection.
A prospective cohort study surveyed 170 adult patients who had recovered from COVID-19 1 year prior, during March and April of 2020. The patients participated in a telephone survey during March and April of 2021.
The age-adjusted COVID-19-associated hospitalization rate (273; rate ratio [RR], 2.72) and the age-adjusted COVID-19 related mortality rate (104; RR, 2.86) among AI/AN individuals were nearly three times those of White study participants. [62]
A study from South Korea found that older children and adolescents are more likely to transmit SARS CoV-19 to family members than are younger children. The researchers reported that the highest infection rate (18.6%) was in household contacts of patients with COVID-19 aged 10 to 19 years, and the lowest rate (5.3%) was in household contacts of those aged 0 to 9 years. [64] Teenagers have been the source of clusters of cases, illustrating the role of older children. [65] 2ff7e9595c
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