The Effectiveness of Face Masks in Preventing COVID-19 Transmission: A Systematic Review.

INTRODUCTION: Since the beginning of the COVID-19 pandemic, face masks have been among the cornerstones of COVID-19 prevention. Therefore, evaluating their preventive effects against COVID-19 is crucial. This review aimed to systematically search for the systematic review articles that explored the role of various types of face masks in preventing COVID-19. METHODS: We browsed the keywords of this study in the online databases of Scopus, Web of Science, PubMed, and Cochrane on 10th January 2023 and retrieved all the relevant systematic review articles. The records were downloaded into an Endnote file, and the duplicates were removed. A two-step screening process consisting of title/abstract and full-text screenings was conducted to select the most relevant articles. To ensure the validity and reliability of the results, this study adhered to the PRISMA protocol. RESULTS: A total of 28 systematic reviews were included in this review. Most studies found that face masks are beneficial against viral respiratory infections, such as COVID-19. Different types of masks were evaluated in included studies. It appeared that mask efficacy depends on the material, layers, fitting on the face and user compliance. N 95 respirator had maximum efficacy, especially when used continuously. CONCLUSION: Face masks have a beneficial effect against COVID-19. Home masks are less protective than surgical masks or N95 personal breathing masks. Besides, the use of masks may elicit a false sense of security in people, which may lead to poor hand hygiene and violation of social distancing. Therefore, the necessary training should be provided to the public to increase awareness and encourage the right practice of using the mask, emphasizing the preventive effects of washing hands, social distancing, and using a face mask against COVID-19.

SARS-CoV-2 Infection and Severity in Patients with Hematologic Malignancies: A Systematic Review.

INTRODUCTION: Earlier reports described the possibility of higher SARS-CoV-2 infection and severity in patients with hematological malignancies. Given the importance and incidence of these malignancies, we aimed to systematically review SARS-CoV-2 infection and severity in patients with hematologic cancers. METHODS: We retrieved the relevant records by searching the keywords in online databases of PubMed, Web of Science, Cochrane, and Scopus on December 31st , 2021. A two-step screening; title/abstract and full-text screening, was employed to select the eligible studies. These eligible studies entered the final qualitative analysis. The study is adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the reliability and validity of the results. RESULTS: Forty studies concerning different hematologic malignancies and the effect of COVID-19 infection on them were included in the final analysis. The findings showed that in general, the prevalence of SARS-CoV-2 infection and the severity of the disease are often higher in hematologic malignancies and the patients could experience higher morbidity and mortality compared to general populations. CONCLUSION: It appeared that individuals with hematologic malignancies are more vulnerable to COVID-19 infection and they experience more severe disease with higher mortality rates. The presence of other comorbidities could also deteriorate this situation. Further Investigation is recommended to evaluate the outcome of COVID-19 infection in different subtypes of hematologic malignancies.

Telemedicine technologies and applications in the era of COVID-19 pandemic: A systematic review.

INTRODUCTION: Telemedicine services saw substantial surges in their use during the COVID-19 pandemic due to the lockdowns and characteristics of the pandemic. Therefore, the authors aimed to systematically review the telemedicine services provided during the COVID-19 pandemic and their potential applications. METHODS: The authors searched PubMed, Scopus, and Cochrane databases on September 14, 2021. Then, the retrieved records underwent two-step title/abstract and full-text screening processes, and the eligible articles were included for qualitative synthesis. RESULTS: The review of studies demonstrated that the telephone is listed 38 times, making it the most common technology used in telemedicine. Video conferencing is also mentioned in 29 articles, as well as other technologies: Mobile-health (n = 15), Virtual reality (n = 7). According to the findings of the present study, Tele-follow-up (n = 24), Tele-consulting (n = 20), Virtual visits (20), and Tele-monitoring (n = 18) were the most widely used telemedicine applications. CONCLUSION: Telemedicine has been an effective approach to COVID-19 management. Telemedicine technology is going to play a key role in the future of health medicine, patient consultation, and many other extended applications of health care in remote rural locations.

Post-Exposure Prophylaxis for COVID-19: A Systematic Review.

INTRODUCTION: SARS-CoV-2 cause pneumonia can spread across the lung and lead to acute respiratory distress syndrome (ARDS) in severe cases. Post-exposure prophylaxis has shown great potential to prevent the transmission of some viral infections; however, such results for COVID-19 are still inconclusive. METHODS: Therefore, the aim of this study was to systematically review the resources that utilized postexposure prophylaxis (PEP) for COVID-19 and the possible clinical benefits of such drugs. An organized search of relevant literature was done using the keywords and search queries on public databases of Cochrane, PubMed, Web of Science and Scopus from December 2019 to August 23, 2021. Original resources that had the inclusion criteria were included after two-phase title/abstract and full-text screenings. This review adhered to the Preferred Reporting Items for Systematic Reviews and MetaAnalysis (PRISMA) statement. RESULTS: Out of 841 retrieved records 17 resources were appropriate to include in the systematic review. Hydroxychloroquine with a daily dose of 400-800 mg and a duration of 5-14 days was the most frequently used agent for PEP. Chloroquine was recommended to use to control treatment in patients with mild to severe COVID-19 pneumonia. Other agents like Lopinavir-ritonavir (LPV/r), angiotensinconverting enzyme inhibitors (ACEIs), Angiotensin receptor blockers (ARBs), Vitamin D, arbidol, thymosin drugs, and Xin guan no.1 (XG.1, a Chinese formula medicine) have also been applied in some studies. CONCLUSION: Current evidence demonstrated no established clinical benefits of any drug as PEP in individuals with COVID-19. However, scarce indication occurs for the beneficial effects of some agents, but more studies are needed to explore such effects.

Minimum infective dose of severe acute respiratory syndrome coronavirus 2 based on the current evidence: A systematic review.

Objective: Understanding the minimum infective dose is significant for risk assessment in the performance of suitable infection control strategies in healthcare centers. However, the literature lacks strong evidence regarding this value for severe acute respiratory syndrome coronavirus 2. Therefore, the aim of this study was to investigate the minimum infectious dose of coronavirus disease 2019. Methods: We searched the databases of PubMed, Scopus, Web of Science, and Cochrane and retrieved all the relevant literature by 25 July 2021. The records were downloaded into the EndNote software and underwent title/abstract and full-text screenings. A summary of included studies was organized into tables for further analysis, interpretation, and drafting of the results. Results: Nineteen studies including the laboratory data on human and animal hosts were selected based on the eligibility criteria. All the literature reported on the infective dose, particularly in humans. The main methods for measurement of infection were through tissue culture infectious dose (TCID50) and counting plaque-forming units. The range of minimum infective was 1.26-7 × 106.25 PFU. Conclusion: In this study, we have presented a range of minimum infective doses in humans and various animal species. Such numbers can possibly vary between the individuals based on numerous demographic, immunologic, or other factors.

Gut microbiota and COVID-19: A systematic review.

Background and Aims: Alteration in humans' gut microbiota was reported in patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The gut and upper respiratory tract (URT) microbiota harbor a dynamic and complex population of microorganisms and have strong interaction with host immune system homeostasis. However, our knowledge about microbiota and its association with SARS-CoV-2 is still limited. We aimed to systematically review the effects of gut microbiota on the SARS-CoV-2 infection and its severity and the impact that SARS-CoV-2 could have on the gut microbiota. Methods: We searched the keywords in the online databases of Web of Science, Scopus, PubMed, and Cochrane on December 31, 2021. After duplicate removal, we performed the screening process in two stages; title/abstract and then full-text screening. The data of the eligible studies were extracted into a pre-designed word table. This study adhered to the PRISMA checklist and Newcastle-Ottawa Scale Bias Assessment tool. Results: Sixty-three publications were included in this review. Our study shows that among COVID-19 patients, particularly moderate to severe cases, the gut and lung microbiota was different compared to healthy individuals. In addition, the severity, and viral load of COVID-19 disease would probably also be influenced by the gut, and lung microbiota's composition. Conclusion: Our study concludes that there was a significant difference in the composition of the URT, and gut microbiota in COVID-19 patients compared to the general healthy individuals, with an increase in opportunistic pathogens. Further, research is needed to investigate the probable bidirectional association of COVID-19 and human microbiome.

The Impact of COVID-19 Pandemic on the Levels of Physical Activity: A Systematic Review.

INTRODUCTION: Earlier studies demonstrated a decreased level of physical activity (PA) during the COVID-19 pandemic. Therefore, we aimed to systematically review the relevant studies among various age groups and explore the impact on physical and mental health. METHODS: We searched and retrieved all relevant articles using the keywords on the online databases of PubMed, Scopus, and Cochrane from the start of the pandemic until May 3rd, 2021. A two-phase screening process of identified records was carried out to shortlist the most relevant studies. First, the studies were evaluated based on their title/abstract, and then the full-text of included studies was thoroughly read. The eligible studies based on the eligibility criteria were included in this review. RESULTS: A total of 57 studies were included based on the eligibility criteria. Lockdowns and infection with SARS-CoV-2 have led to a decreased level of PA in the general population compared to the prepandemic era. Men had significantly less PA compared to women in some studies, probably due to higher pre-pandemic PA. The level of PA among those with chronic diseases also significantly diminished, putting them at a higher risk of cardiovascular incidents. Sedentary lifestyles have dominated people's life, including adolescents and university students. The increased levels of mental health issues, such as depression, anxiety, and occupational stress, have been suggested to contribute to the decreased PA. On the other hand, the decreased PA appeared to lead to more mental health issues. Fortunately, the decreasing trend of PA seemed to taper towards the end of the quarantines. CONCLUSION: Overall, the COVID-19 pandemic and subsequent quarantines reduced PA among all age groups and both sexes and had detrimental effects on people's physical and mental health. We suggest countries implement strategies to alleviate restrictions and encourage people to exercise in safe environments and prepare healthy routines for themselves.

Evaluating the effects of air disinfectants in decontamination of COVID-19 aerosols.

Introduction: Airborne transmission is the most  crucial mode of COVID-19 transmission. Therefore, disinfecting the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) aerosols float can have important implications in limiting COVID-19 transmission. Herein, we aimed to review the studies that utilized various disinfectants to decontaminate and inactivate the SARS-CoV-2 aerosols. Methods: This study was a review that studied related articles published between December 1, 2019 and August 23, 2022. We searched the online databases of PubMed, Scopus, Web of Science, Cochrane, on August 23, 2021. The studies were downloaded into the EndNote software, duplicates were removed, and then the studies were screened based on the inclusion/exclusion criteria. The screening process involved two steps; first, the studies were screened based on their title and abstract and then their full texts. The included studies were used for the qualitative analysis. Results: From 664 retrieved records, only 31 met the inclusion criteria and were included in the final qualitative analysis. Various materials like Ozone, H2O2, alcohol, and TiO2 and methods like heating and using Ultraviolet were described in these studies to disinfect places contaminated by COVID-19. It appeared that the efficacy of these disinfectants varies considerably depending on the situation, time, and ultimately their mode of application. Conclusion: Following reliable protocols in combination with the proper selection of disinfectant agents for each purpose would serve to achieve desired elimination of the SARS-CoV-2 transmission.

COVID-19 Vaccines' Protection Over Time and the Need for Booster Doses; a Systematic Review.

Introduction: Controversies existed regarding the duration of COVID-19 vaccines' protection and whether receiving the usual vaccine doses would be sufficient for long-term immunity. Therefore, we aimed to systematically review the studies regarding the COVID-19 vaccines' protection three months after getting fully vaccinated and assess the need for vaccine booster doses. Methods: The relevant literature was searched using a combination of keywords on the online databases of PubMed, Scopus, Web of Science, and Cochrane on September 17th, 2021. The records were downloaded and the duplicates were removed. Then, the records were evaluated in a two-step process, consisting of title/abstract and full-text screening processes, and the eligible records were selected for the qualitative synthesis. We only included original studies that evaluated the efficacy and immunity of COVID-19 vaccines three months after full vaccination. This review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement to ensure the reliability of results. Results: Out of the 797 retrieved records, 12 studies were included, 10 on mRNA-based vaccines and two on inactivated vaccines. The majority of included studies observed acceptable antibody titers in most of the participants even after 6 months; however,it appeared that the titers could also decrease in a considerable portion of people. Due to the reduction in antibody titers and vaccine protection, several studies suggested administering the booster dose, especially for older patients and those with underlying conditions, such as patients with immunodeficiencies. Conclusion: Studies indicated that vaccine immunity decreases over time, making people more susceptible to contracting the disease. Besides, new variants are emerging, and the omicron variant is continuing to spread and escape from the immune system, indicating the importance of a booster dose.

A global, regional, and national survey on burden and Quality of Care Index (QCI) of bladder cancer: The global burden of disease study 1990-2019.

INTRODUCTION: Bladder cancer (BCa) is the second most common genitourinary cancer and among the leading causes of cancer-related deaths. We aimed to assess BCa quality of care (QOC) utilizing a novel multi-variable quality of care index (QCI). MATERIALS AND METHODS: Data were retrieved from the Global Burden of Disease 1990-2019 database. QCI scores were calculated using four indices of prevalence-to-incidence ratio, Disability-Adjusted Life Years-to-prevalence ratio, mortality-to-incidence ratio, and Years of Life Lost-to-Years Lived with Disability ratio. We used principal component analysis to allocate 0-100 QCI scores based on region, age groups, year, and gender. RESULTS: Global burden of BCa is on the rise with 524,305 (95% UI 475,952-569,434) new BCa cases and 228,735 (95% UI 210743-243193) deaths in 2019, but age-standardized incidence and mortality rates did not increase. Global age-standardized QCI improved from 75.7% in 1990 to 80.9% in 2019. The European and African regions had the highest and lowest age-standardized QCI of 89.7% and 37.6%, respectively. Higher Socio-demographic index (SDI) quintiles had better QCI scores, ranging from 90.1% in high SDI to 30.2% in low SDI countries in 2019; however, 5-year QCI improvements from 2014 to 2019 were 0.0 for high and 4.7 for low SDI countries. CONCLUSION: The global QCI increased in the last 30 years, but the gender disparities remained relatively unchanged despite substantial improvements in several regions. Higher SDI quintiles had superior QOC and less gender- and age-based inequalities compared to lower SDI countries. We encourage countries to implement the learned lessons and improve their QOC shortcomings.

A systematic review and meta-analysis of the epidemiological characteristics of COVID-19 in children.

BACKGROUND: Several individual studies from specific countries have reported rising numbers of pediatric COVID-19 cases with inconsistent reports on the clinical symptoms including respiratory and gastrointestinal symptoms as well as diverse reports on the mean age and household exposure in children. The epidemiological characteristics of COVID-19 in children are not fully understood, hence, comprehensive meta-analyses are needed to provide a better understanding of these characteristics. METHODS: This review was conducted in Medline, Scopus, Cochrane library, Embase, Web of Science, and published reports on COVID-19 in children. Data were extracted by two independent researchers and a third researcher resolved disputes. STATA software and the random-effect model were used in the synthesis of our data. For each model, the heterogeneity between studies was estimated using the Q Cochrane test. Heterogeneity and publication bias were calculated using the I2 statistic and Egger's/Begg's tests. RESULTS: The qualitative systematic review was performed on 32 articles. Furthermore, the meta-analysis estimated an overall rate of involvement at 12% (95% CI: 9-15%) among children, with an I2 of 98.36%. The proportion of household exposure was calculated to be 50.99% (95% CI: 20.80%-80.80%) and the proportion of admitted cases was calculated to be 45% (95% CI: 24%-67%). Additionally, the prevalence of cough, fatigue, fever and dyspnea was calculated to be 25% (95% CI: 0.16-0.36), 9% (95% CI: 0.03-0.18), 33% (95% CI: 0.21-0.47) and 9% (95% CI: 0.04-0.15), respectively. It is estimated that 4% (95% CI: 1-8%) of cases required intensive care unit admission. CONCLUSIONS: The pediatric clinical picture of COVID-19 is not simply a classic respiratory infection, but unusual presentations have been reported. Given the high incidence of household transmission and atypical clinical presentation in children, we strongly recommend their inclusion in research and population-based preventive measures like vaccination as well as clinical trials to ensure efficacy, safety, and tolerability in this age group.

The relationship between C-reactive protein and levels of various cytokines in patients with COVID-19: A systematic review and correlation analysis.

Introduction: C-reactive protein (CRP) and cytokines levels could alter in patients with coronavirus disease (COVID-19) due to the inflammatory response caused by the virus. This analysis aimed to assess the relationship between the CRP levels and the levels of various cytokines in COVID-19 patients. Materials and Methods: We searched the databases of PubMed, Cochrane, and Web of Science for relevant articles on May 29th, 2021. Applying the inclusion/exclusion criteria, the retrieved records underwent two-phase screenings; first, a title/abstract screening process, and then, a full-text screening to find the eligible studies. Data for study variables were extracted, including the CRP levels and the levels of all reported cytokines. A strong and significant relationship between Interleukins and CRP was defined as: p ≤ 0.05, 0.7 ≤ r ≤ 1. Results: In this study, 103 studies were included for systematic review and correlation analysis. The aggregate mean and SD of study variables were calculated and reported. The correlation between Interleukins and CRP was measured using correlation coefficient (r). It appeared that interleukin (IL)-10 has a moderate and significant relationship with CRP (p ≤ 0.05, r = 0.472). IL-10 predicted almost 10% of CRP changes. Conclusion: This correlation analysis suggests IL-10 is moderately correlated with CRP levels in patients with COVID-19 infection. A better understanding of the pro-inflammatory markers could contribute to the implementation of therapeutic and preventive approaches. More prospective studies are suggested to explore the relationship between CRP and cytokines as potential markers for the early identification of COVID-19 progression and severity.

COVID-19 mortality in patients with immunodeficiency and its predictors: a systematic review.

INTRODUCTION: Patients with immunodeficiency are usually more prone to worse outcomes of infectious diseases. However, there are some disagreements in the context of COVID-19, for example, in patients with human immunodeficiency virus (HIV). Herein, we aimed to systematically review the risk and predictors of COVID-19 mortality in people with primary or secondary immunodeficiency. METHODS: PubMed, Scopus, Web of Science, and Science Direct were searched. We followed a two-step screening process to identify eligible results. We first reviewed the title and abstract of the records and the unqualified studies were removed. Then, their full texts were evaluated based on their coherence with the purpose and inclusion/exclusion criteria, and those eligible for qualitative synthesis were included. RESULTS: Twenty-two articles were included, which investigated a total of 109,326 with primary or secondary immunodeficiencies. Three studies investigated the pediatric and infant population, while other studies were conducted on the adult population. Overall, studies on both primary and secondary immunodeficiency conflicted as some reported higher and some mentioned lower mortality rates in patients with immunodeficiency. CONCLUSIONS: Overall, there were two points of view in both types of immunodeficiencies. The first is the classical viewpoint that all immunodeficient patients are at a higher risk of infection leading to a higher mortality rate. The second types of studies found that immunodeficiency might play a less important or even an inverse role in mortality rates by lowering the severity of the inflammatory response. However, it is important to take note to comorbidities, such as DM, HTN, CAD, ESRD, history of lower respiratory infection, etc., and demographic factors, such as obesity and age > 70 years, as they appear to influence the mortality rate, especially in patients with secondary immunodeficiency.

Minimum infective dose of severe acute respiratory syndrome coronavirus 2 based on the current evidence: A systematic review

Objective: Understanding the minimum infective dose is significant for risk assessment in the performance of suitable infection control strategies in healthcare centers. However, the literature lacks strong evidence regarding this value for severe acute respiratory syndrome coronavirus 2. Therefore, the aim of this study was to investigate the minimum infectious dose of coronavirus disease 2019. Methods: We searched the databases of PubMed, Scopus, Web of Science, and Cochrane and retrieved all the relevant literature by 25 July 2021. The records were downloaded into the EndNote software and underwent title/ and full-text screenings. A summary of included studies was organized into tables for further analysis, interpretation, and drafting of the results. Results: Nineteen studies including the laboratory data on human and animal hosts were selected based on the eligibility criteria. All the literature reported on the infective dose, particularly in humans. The main methods for measurement of infection were through tissue culture infectious dose (TCID50) and counting plaque-forming units. The range of minimum infective was 1.26–7 × 106.25 PFU. Conclusion: In this study, we have presented a range of minimum infective doses in humans and various animal species. Such numbers can possibly vary between the individuals based on numerous demographic, immunologic, or other factors.

Safety and Adverse Events Related to Inactivated COVID-19 Vaccines and Novavax;a Systematic Review.

Introduction: Knowledge of the safety of vaccines is crucial, both to prevent and cure them and to decrease the public hesitation in receiving vaccines. Therefore, this study aimed to systematically review the adverse events reported for inactivated vaccines and Novavax. Methods: In this systematic review, the databases of PubMed, Scopus, Cochrane, and Web of Science were searched on September 15, 2021. Then we identified the eligible studies using a two-step title/abstract and full-text screening process. Data on the subjects, studies, and types of adverse events were extracted and entered in a word table, including serious, mild, local, and systemic adverse events as well as the timing of side effects' appearance. Results: Adverse effects of inactivated coronavirus vaccines side effects were reported from phases 1, 2, and 3 of the vaccine trials. The most common local side effects included injection site pain and swelling, redness, and pruritus. Meanwhile, fatigue, headache, muscle pain, fever, and gastrointestinal symptoms including abdominal pain and diarrhea were among the most common systemic adverse effects. Conclusion: This systematic review indicates that inactivated COVID-19 vaccines, including Sinovac, Sinopharm, and Bharat Biotech, as well as the protein subunit vaccines (Novavax) can be considered as safe choices due to having milder side effects and fewer severe life-threatening adverse events.

COVID-19 in Pediatrics: A Systematic Review of Current Knowledge and Practice.

INTRODUCTION: SARS-CoV-2 is the novel coronavirus that causes severe acute respiratory syndrome and could afflict individuals from all walks of life. Children are usually asymptomatic or represent non-specific mild to moderate symptoms; therefore, they often remain undiagnosed and could be potential reservoirs and silent carriers of the virus. Despite the global attention to COVID-19 and its importance in public health, some clinical and paraclinical aspects of this disease in children are still unclear. Thus, we conducted a comprehensive systematic review of available literature to reflect on the current knowledge and practice of the disease among children. METHODS: This study was a systematic review of current evidence conducted in October 2020. We performed a systematic search using the keywords in online databases. The investigation adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the reliability and validity of extracted literature and results. RESULTS: We selected and reviewed 23 most related studies out of 1744 identified papers in an initial online search based on the inclusion and exclusion criteria of the present review; of whom 13 were original research studies, and 10 were letters to the editors, commentaries, viewpoints, consensus statements, and perspectives. Although due to the origin of the current pandemic, China was the country with the most publications (12 articles), data from several countries have been included in this review. CONCLUSION: COVID-19 can also affect children and cause systemic disease with several internal organ involvements. However, the prevalence, severity, and diversity of the symptoms in children are less than in adults. Cough and fever appear to be some of the most common symptoms, followed by other symptoms such as gastrointestinal manifestations. Comorbidities increase the risk of severe COVID-19 in children, and those without underlying conditions are very unlikely to suffer from severe disease. Mental health issues such as anxiety and depression due to the isolated situation caused by pandemics are common findings in children of early ages and should be seriously considered in current practice.

Safety and Adverse Events Related to COVID-19 mRNA Vaccines; a Systematic Review.

Introduction: Knowledge of vaccine-related adverse events is crucial as they are among the most important factors that cause hesitation in receiving vaccines. Therefore, we aimed to systematically review the adverse events related to the mRNA vaccines reported in the literature. . Method: A systematic literature search was carried out in the databases of Scopus, PubMed, Cochrane, and Web of Science. We selected original studies that explored the side effects of mRNA COVID-19 vaccines using a two-phase (title/abstract and full-text) screening process. . Results: Cardiac complications were the most commonly reported severe adverse events. It appeared that systemic adverse reactions are more common after the second dose of vaccines. The number of adverse effects reported after the Pfizer vaccine was higher than other vaccines, mostly due to its earlier approval and more widespread use throughout the world. Cardiac adverse events had a higher prevalence but no significant association has been found between COVID-19 mRNA vaccines and cardiac adverse events except for myopericarditis. . Conclusion: Vaccines play a crucial role in controlling the COVID-19 pandemic and decreasing mortalities and the results of the present review acknowledge the fact that the benefits outweigh the adverse events of these vaccines. .

Vaccines for COVID-19: A Systematic Review of Feasibility and Effectiveness.

INTRODUCTION: Many potential vaccines for COVID-19 are being studied and developed. Several studies have reported on the safety and efficacy of these vaccines. This systematic review aimed to report on the current evidence concerning the feasibility and effectiveness of vaccines for COVID-19. METHODS: A systematic search was carried out utilizing the keywords in the online databases, including Scopus, Web of Science, PubMed, Embase, and Cochrane. We included both human and non-human studies because of the vaccine novelty, limiting our ability to include sufficient human studies. RESULTS: This review showed several SARS-CoV-2 vaccines to be currently under development using different platforms, including eight vaccines that are adenovirus-based vectors, six vaccines that are RNA-based formulations, one vaccine being DNA-based formulation, and other vaccines using other platforms, including lipid nanoparticles. Although the safety and efficacy profiles of these vaccines are still under debate, some countries have allowed for emergency use of some vaccines in at-risk populations, such as healthcare workers and the elderly. CONCLUSION: It is crucial to gather as much clinically relevant evidence as possible regarding the immunogenicity, efficacy, and safety profiles of available vaccines and adhere wisely to CDC protocols and guidelines for vaccine production.

COVID-19 mortality and its predictors in the elderly: A systematic review.

Background and Aims: Older people have higher rates of comorbidities and may experience more severe inflammatory responses; therefore, are at higher risk of death. Herein, we aimed to systematically review the mortality in coronavirus disease 2019 (COVID-19) patients and its predictors in this age group. Methods: We searched PubMed, Web of Science, and Science Direct using relevant keywords. Retrieved records underwent a two-step screening process consisting of title/abstract and full-text screenings to identify the eligible studies. Results: Summarizing findings of 35 studies demonstrated that older patients have higher mortality rates compared to the younger population. A review of articles revealed that increasing age, body mass index, a male gender, dementia, impairment or dependency in daily activities, presence of consolidations on chest X-ray, hypoxemic respiratory failure, and lower oxygen saturation at admission were risk factors for death. High d-dimer levels, 25-hydroxy vitamin D serum deficiencies, high C-reactive protein (≥5 mg/L) levels plus any other abnormalities of lymphocyte, higher blood urea nitrogen or lactate dehydrogenase, and higher platelet count were predictors of poor prognosis and mortality in the elderly. Studies have also shown that previous treatment with renin-angiotensin-aldosterone system inhibitors, pharmacological treatments of respiratory disorders, antibiotics, corticosteroids, vitamin K antagonist, antihistamines, azithromycin, Itolizumab (an anti-CD6 monoclonal antibody) in combination with other antivirals reduces COVID-19 worsening and mortality. Vaccination against seasonal influenza might also reduce COVID-19 mortality. Conclusion: Overall, a critical consideration is necessary for the care and management of COVID-19 in the aged population considering the drastic contrasts in manifestation and prognosis compared to other age groups. Mortality from COVID-19 is independently associated with the patient's age. Elderly patients with COVID-19 are more vulnerable to poor outcomes. Thus, strict preventive measures, timely diagnosis, and aggressive therapeutic/nontherapeutic care are of great importance to reduce acute respiratory distress syndrome and severe complications in older people.

COVID‐19 mortality and its predictors in the elderly: A systematic review

Background and AimsOlder people have higher rates of comorbidities and may experience more severe inflammatory responses;therefore, are at higher risk of death. Herein, we aimed to systematically review the mortality in coronavirus disease 2019 (COVID‐19) patients and its predictors in this age group.MethodsWe searched PubMed, Web of Science, and Science Direct using relevant keywords. Retrieved records underwent a two‐step screening process consisting of title/ and full‐text screenings to identify the eligible studies.ResultsSummarizing findings of 35 studies demonstrated that older patients have higher mortality rates compared to the younger population. A review of articles revealed that increasing age, body mass index, a male gender, dementia, impairment or dependency in daily activities, presence of consolidations on chest X‐ray, hypoxemic respiratory failure, and lower oxygen saturation at admission were risk factors for death. High d‐dimer levels, 25‐hydroxy vitamin D serum deficiencies, high C‐reactive protein (≥5 mg/L) levels plus any other abnormalities of lymphocyte, higher blood urea nitrogen or lactate dehydrogenase, and higher platelet count were predictors of poor prognosis and mortality in the elderly. Studies have also shown that previous treatment with renin–angiotensin–aldosterone system inhibitors, pharmacological treatments of respiratory disorders, antibiotics, corticosteroids, vitamin K antagonist, antihistamines, azithromycin, Itolizumab (an anti‐CD6 monoclonal antibody) in combination with other antivirals reduces COVID‐19 worsening and mortality. Vaccination against seasonal influenza might also reduce COVID‐19 mortality.ConclusionOverall, a critical consideration is necessary for the care and management of COVID‐19 in the aged population considering the drastic contrasts in manifestation and prognosis compared to other age groups. Mortality from COVID‐19 is independently associated with the patient's age. Elderly patients with COVID‐19 are more vulnerable to poor outcomes. Thus, strict preventive measures, timely diagnosis, and aggressive therapeutic/nontherapeutic care are of great importance to reduce acute respiratory distress syndrome and severe complications in older people.