Transmission Cycle of SARS-CoV and SARS-CoV-2

Corrigendum: Evolution, ecology, and zoonotic transmission of betacoronaviruses: A review

[This corrects the article DOI: 10.3389/fvets.2021.644414.].

Knowledge, practice and attitude associated with SARS-CoV-2 Delta Variant among adults in Jordan

COVID-19 infection is a global pandemic health emergency. This contagious disease was caused by the Severe Acute Respiratory Syndrome Coronavirus‑2 (SARS‑CoV-2) which is mutating over time. In 2021, the Delta variant became the most dominant transmissible form. During the crisis, human practice and knowledge were critical in the overall efforts to encompass the outbreak. A cross-sectional, web-based approach was conducted among adults in Jordan to quantify knowledge, attitude, and practices towards SARS-CoV-2 (Delta variant). This research was carried out between 15th April and 15th of May 2021. The study questionnaire consisted of four sections including the participant's demographics, knowledge, practices and attitude. Comparative evaluation of responses was accomplished using a scoring system. Respondents who scored above the mean score (60%) on the item measured were categorized as knowledgeable, having a positive attitude, and good practices. Participants were allocated to one of the three groups; medical, non-medical and others (unemployed and housewives). Data collected was analyzed using Statistical Package for Social Sciences (SPSS) version 23.0 software. A variance test to assess the statistical difference between groups was used. Pearson's chi-squared test was applied to compare the variables and identify significant predictors. Of the participants, 308 (66%) were in the age group of 18-25yrs, 392 (84.1%) females, 120 (25.8%) employed and 346 (74.2%) unemployed. The principle source of knowledge was social media (291, 62.4%). Interestingly, participants had adequate overall knowledge. The mean knowledge score was 22.6 (± 0.19), 20.6 (± 0.19), and 21.3 (± 0.18) for the medical, the non-medical and the others group, respectively. Also, participants showed a positive attitude and good practices towards SARS-CoV-2 (Delta variant). The mean practice score for medical, the non-medical and the others groups was 7.35 (± 0.25), 7.38 (± 0.24), 7.35 (± 0.24) and the mean attitude score was 10.8 (± 0.16), 9.4 (± 0.21), 9.5 (± 0.22), respectively. The studied groups generally had good knowledge, positive attitudes and good practices about SARS-CoV-2 (Delta variant). This was expected due to the authorities' successful management of the pandemic and the high educational level of the Jordanian society, bearing in mind the economic and social impact of COVID-19 disease.

Advances in the design and development of SARS-CoV-2 vaccines

Since the end of 2019, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide. The RNA genome of SARS-CoV-2, which is highly infectious and prone to rapid mutation, encodes both structural and nonstructural proteins. Vaccination is currently the only effective method to prevent COVID-19, and structural proteins are critical targets for vaccine development. Currently, many vaccines are in clinical trials or are already on the market. This review highlights ongoing advances in the design of prophylactic or therapeutic vaccines against COVID-19, including viral vector vaccines, DNA vaccines, RNA vaccines, live-attenuated vaccines, inactivated virus vaccines, recombinant protein vaccines and bionic nanoparticle vaccines. In addition to traditional inactivated virus vaccines, some novel vaccines based on viral vectors, nanoscience and synthetic biology also play important roles in combating COVID-19. However, many challenges persist in ongoing clinical trials.

Alcohol-Based Sanitizers: An Effective Means for Preventing the Spread of Contagious Viral Diseases Including COVID-19

The global community is struggling with the highly contagious COVID-19. Returning to \normal life" now poses risks, and the use of appropriate protective measures has become necessary to continue daily life and protect public health. The main protective measures to prevent transmission of COVID-19 are masks, soaps and disinfectants. Because coronavirus is a \lipid-enveloped virus", it is very sensitive to lipid-dissolving chemicals and can therefore be effectively removed by washing hands sufficiently with soap and water. However, using an alcohol-based disinfectant is a more viable option for outdoor use. Alcohol-based disinfectants are inexpensive, immediately effective, easy to use and better tolerated by the skin compared to other disinfectants. WHO recommends disinfectants containing 75% isopropanol or 80% ethanol as highly effective in inactivating the SARS-CoV-2-virus. The current review discusses the role of alcohol-based hand sanitizers (ABHS) in preventing the spread of viruses, their side effects on human health, and suggests the use of alcohol-based sanitizers as potentially effective in combating the current epidemic.

SARS-CoV-2: An Overview of Virus Genetics, Transmission, and Immunopathogenesis

The human population is currently facing the third and possibly the worst pandemic caused by human coronaviruses (CoVs). The virus was first reported in Wuhan, China, on 31 December 2019 and spread within a short time to almost all countries of the world. Genome analysis of the early virus isolates has revealed high similarity with SARS-CoV and hence the new virus was officially named SARS-CoV-2. Since CoVs have the largest genome among all RNA viruses, they can adapt to many point mutation and recombination events; particularly in the spike gene, which enable these viruses to rapidly change and evolve in nature. CoVs are known to cross the species boundaries by using different cellular receptors. Both animal reservoir and intermediate host for SARS-CoV-2 are still unresolved and necessitate further investigation. In the current review, different aspects of SARS-CoV-2 biology and pathogenicity are discussed, including virus genetics and evolution, spike protein and its role in evolution and adaptation to novel hosts, and virus transmission and persistence in nature. In addition, the immune response developed during SARS-CoV-2 infection is demonstrated with special reference to the interplay between immune cells and their role in disease progression. We believe that the SARS-CoV-2 outbreak will not be the last and spillover of CoVs from bats will continue. Therefore, establishing intervention approaches to reduce the likelihood of future CoVs spillover from natural reservoirs is a priority.

Evolution, Ecology, and Zoonotic Transmission of Betacoronaviruses: A Review

Coronavirus infections have been a part of the animal kingdom for millennia. The difference emerging in the twenty-first century is that a greater number of novel coronaviruses are being discovered primarily due to more advanced technology and that a greater number can be transmitted to humans, either directly or via an intermediate host. This has a range of effects from annual infections that are mild to full-blown pandemics. This review compares the zoonotic potential and relationship between MERS, SARS-CoV, and SARS-CoV-2. The role of bats as possible host species and possible intermediate hosts including pangolins, civets, mink, birds, and other mammals are discussed with reference to mutations of the viral genome affecting zoonosis. Ecological, social, cultural, and environmental factors that may play a role in zoonotic transmission are considered with reference to SARS-CoV, MERS, and SARS-CoV-2 and possible future zoonotic events.

COVID-19 and gastrointestinal system: A brief review

COVID-19 is a recent pandemic that is still a major health problem of modern times and already more than 17.5 lakhs people succumbed to this deadly disease. This disease is caused by novel coronavirus which is named SARS-COV-2 by the International Committee on Taxonomy of Viruses. This virus originated from Wuhan city in Hubei province of China in December 2019 and within a short period spread across the many countries in the globe. There are a lot of basic as well as clinical research is going on to study the mode of transmission and the mechanism of action of SARS-COV-2 infection and its therapeutics. SARS-COV-2 is not only known to infect lungs, but it also infects other organs in the human body including the gastrointestinal (GI) tract, the liver, and the pancreas via the angiotensin-converting enzyme (ACE) 2, an important component of the renin-angiotensin system. In this short review, we are mainly discussing the mode of SARS-COV-2 transmission, physiological counterbalancing roles of ACE2 and ACE and the tissue patterns of ACE2 expression, and the overall effect of COVID19 on human gastrointestinal System. Therefore, this review sheds light on the possible mechanism of SARS-COV-2 infection in the GI system and its pathological symptoms raising a potential possibility of GI tract acting as a secondary site for SARS-CoV-2 tropism and infection. Finally, future studies to understand the fecal-oral transmission of the virus and the correlation of viral load and severity of GI symptoms are proposed to gain knowledge of the GI symptoms in COVID-19 to aid in early diagnosis and prognosis.

Chasing COVID-19 through SARS-CoV-2 spike glycoprotein

An ongoing pandemic Coronavirus disease (COVID-19), caused by a newly emerged Coronavirus, SARS-CoV-2 has affected millions of people globally. One of the most crucial structural proteins of SARS-CoV-2 is the Spike glycoprotein (S-glycoprotein), for which the first de novo modelling was envisaged by our group in early 2020, and was superimposed to its predecessor SARS-CoV S-glycoprotein, to determine structural divergence, glycosylation and antigenic variation between SARS-CoV-2 and SARS-CoV. S-glycoprotein is involved in binding with the cellular receptor, membrane fusion, internalization via angiotensin-converting enzyme 2 (ACE2) receptor, and tissue tropism. Upon internalization into the target host cells, the viral genome encodes two precursor polypeptides which get processed into 16 mature nonstructural proteins that play a crucial role in replication and transcription of SARS-CoV-2. Currently S-glycoprotein is one of the most vital targets for vaccine and therapeutics development for COVID-19.

Omega 3 Fatty Acids and COVID-19: A Comprehensive Review

The rapid international spread of severe acute respiratory syndrome coronavirus 2 responsible for coronavirus disease 2019 (COVID-19) has posed a global health emergency in 2020. It has affected over 52 million people and led to over 1.29 million deaths worldwide, as of November 13th, 2020. Patients diagnosed with COVID-19 present with symptoms ranging from none to severe and include fever, shortness of breath, dry cough, anosmia, and gastrointestinal abnormalities. Severe complications are largely due to overdrive of the host immune system leading to "cytokine storm". This results in disseminated intravascular coagulation, acute respiratory distress syndrome, multiple organ dysfunction syndrome, and death. Due to its highly infectious nature and concerning mortality rate, every effort has been focused on prevention and creating new medications or repurposing old treatment options to ameliorate the suffering of COVID-19 patients including the immune dysregulation. Omega-3 fatty acids are known to be incorporated throughout the body into the bi-phospholipid layer of the cell membrane leading to the production of less pro-inflammatory mediators compared to other fatty acids that are more prevalent in the Western diet. In this article, the benefits of omega-3 fatty acids, especially eicosapentaenoic acid and docosahexaenoic acid, including their anti-inflammatory, immunomodulating, and possible antiviral effects have been discussed.

COVID-19: benefits and risks of passive immunotherapeutics

Passive immunotherapeutics (PITs), including convalescent plasma, serum, or hyperimmune immunoglobulin, have been of clinical importance during sudden outbreaks since the early twentieth century for the treatment of viral diseases such as severe acute respiratory syndrome (SARS), middle east respiratory syndrome (MERS) and swine flu (H1N1). With the recent SARS-CoV-2 pandemic, wherein effective antivirals and vaccines are still lacking, an interest in convalescent plasma therapy as a lifesaving option has resurfaced due to its capacity for antigenic neutralization and reducing viremia. This review summarizes convalescent blood products (CBPs) in terms of current technologies and the shortcomings related to the collection, manufacture, pathogen inactivation, and banking of CBPs, with a specific focus on their plausible applications, benefits, and risks in the COVID-19 pandemic.

Early geography of the coronavirus disease outbreak in Nigeria

An understanding of the COVID-19 spread is growing around the world, yet little is known of Africa. This paper explores the time-space geographies of COVID-19 infection focusing on Africa and Nigeria especially. We appraise the global-to-local situation of confirmed cases, deaths and recoveries as well as measures engaged in response to the pandemic. Findings reveal that South Africa accounts for 40% of the total confirmed cases in Africa, followed by Egypt (18%), Nigeria (6.8%), Ghana (4.6%) and Algeria (3.6). Our study shows a significant relationship between population density and COVID-19 cases in Nigeria (R2 = 0.76; y = 2.43x - 268.7). This expression suggests that high population densities catalyze the spread of COVID-19. While Nigeria has only recorded about 25,964 cases as at the time of writing, the country is struggling to match pressures from rising cases as a result of existing disparities in health care systems.