Pathophysiology of COVID-19: Why Children Fare Better than Adults?

Gastrointestinal Manifestations, Clinical Characteristics and Outcomes of COVID-19 in Adult and Pediatric Patients

BACKGROUND

Italy was the first country in Europe to report a SARS-CoV-2 case. Since then, the country has suffered a large number of COVID-19 infections both in adults and children. This disease has been shown to lead to different outcomes in these two groups, which often present varying symptoms and comorbidities.

AIM

Therefore, we aimed to evaluate the symptoms, comorbidities and laboratory values in adults and children.

METHODS

We present the characteristics of 1,324 adults and 563 pediatric COVID-19 Italian patients. The data was retrieved from studies published in Italy and found via PubMed and Google Scholar.

RESULTS

The virus appeared to affect adults more than children and men more than women, and to result in more severe outcomes in patients with abnormal laboratory values and a higher number of comorbidities. Adults are at higher risk for complications and death, and they usually present with fever, respiratory symptoms, cough, fatigue, diarrhea, myalgia, and/or loss of taste, smell, or appetite. Children usually have a milder disease progression and usually present with fever, cough, rhinorrhea, pharyngitis, sore throat, pneumonia, GI symptoms (diarrhea, vomiting, abdominal pain), fatigue, and dyspnea.

CONCLUSION

Our findings support early reports that showed that SARS-CoV-2 is associated with more common asymptomatic cases and milder clinical outcome in children than in adults. Acute respiratory distress syndrome and Multisystem inflammatory syndrome in children (systemic vasculitis) are the most severe disease progressions for adults and children, respectively.

Megadose Methylprednisolone for Immune Thrombocytopenia in an Infant Positive for SARS-CoV-2: A Case Report

Patient: Male, 9-month-old

Final Diagnosis: Newly diagnosed ITP

Symptoms: Petechiae on the forehead • cheeks • mouth • extremities. The patient is febrile, had rhinorrhea for three days previously. The patient is pale, weak, cannot drink

Medication: —

Clinical Procedure: The patient had immunizations of the Measles-Rubella vaccine 19 days before. Physical examination: Eye, ENT, and mouth, no abnormalities. Heart and Lungs within normal limits. Abdomen: there was no organomegaly – there neither lymphadenopathy nor a congenital anomaly

Specialty: Hematology • Infectious Diseases • Pediatrics and Neonatology

Pathophysiology and Clinical Presentation of COVID-19 in Children: Systematic Review of the Literature

Introduction: Coronavirus disease 2019 (COVID-19) is due to severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) infection, which belongs to beta-coronaviruses of the Coronaviridae family. SARS-coV-2 causes acute respiratory infection with varying severity in different age groups, wherein adults can develop severe disease, while children are relatively spared until now, with COVID-19 in children accounting for only 1-5% of diagnosed cases. Although COVID-19 incidence rate in children is relatively low, their protection from COVID-19 is still a matter of increasing concern as children constitute a large vulnerable population. In order to develop effective therapeutic management and preventive measures against COVID-19 in children, there is an urgent need for a better understanding of its pathophysiology at the molecular level and clinical presentation as well as possible protective mechanisms in the pediatric population. Objectives: There is limited data regarding the incidence and clinical presentation of SARS-CoV-2 infection in children. Our goal was to understand the clinical picture and presentation of pediatric patients with confirmed COVID-19. Methods: A systematic literature search of popular medical databases (PubMed, Cochrane Central Register of Clinical Trials and Scopus), restricted to English language publications only, was conducted by us. We chose published peer-reviewed and cross-sectional articles as well as case series providing clinical signs, imaging findings and laboratory results of pediatric patients, using the following inclusion criteria: children aged up to 18 years who tested positive for COVID-19 and in whom SARS-Co-V-2 was detected in the nasal/throat swab by real time polymerase chain reaction (RT-PCR). Conclusion: Our review revealed that, in children, COVID-19 was milder in terms of disease severity and clinical presentation, and it had a better prognosis and a lower mortality rate than adults.

Correlation of SARS-CoV-2 Viral Load in Different Population Subsets: A Study from a Tertiary Care North Indian Hospital

Background

The correlation of SARS-CoV-2 viral load with disease severity in different population subsets is still elusive. There is a scarcity of literature regarding this aspect in Indian Population.

Aim

To study retrospectively the risk factors and the role of viral load with disease severity among different age groups of North Indian population.

Methods

Here we quantified the viral load of 239 positive participants and collected data retrospectively from April 2020 to May 2020 and categorised the patients as per disease severity and population subsets.

Results

Asymptomatic patients were found to have higher viral load than the symptomatic patients, though the difference was not found to be statistically significant. The logistic regression analysis showed that contact with laboratory confirmed cases, SARI and ILI were independent risk factors for acquiring COVID-19 infection.

Conclusion

SARS-CoV-2 viral load is not significantly associated with disease severity among different population subsets. However, there is a need to carry out more studies with a larger number of patients to validate and confirm the above findings.

Detection of SARS-CoV-2 antibodies in pediatric patients: An Iranian referral hospital-based study

BACKGROUND

As the extent of the pandemic and its seroprevalence pattern has been less clarified in pediatrics to date, we aimed to conduct this study to investigate the clinical and laboratory characteristics of COVID-19 in Iranian children, with a focus on evaluating the antibody prevalence and its relation with the laboratory tests.

METHODS

All children with highly suspected COVID-19 were included. Anti-nucleoprotein SARS-CoV-2 were measured using SARS-CoV-2 immunoglobulin M (IgM) and SARS-CoV-2 IgG ELISA kits. Hypothesis testing was carried out through SPSS to unravel any association between the measurement tools and important clinical and laboratory characteristics.

RESULTS

In this study, 254 patients were evaluated and 117 cases (46%) were male. The nucleic acid detection results for patient 55 were negative, but the IgM and IgG results were positive. Totally, 190 patients were tested for IgM in which only 14 (7.3%) had positive tests. Positive IgG was detected in 51 (20%) out of 254 patients; among them, 30 patients had negative SARS-CoV-2 RT-PCR (59%). Lower level of platelets in IgG positive group in comparison with the IgG negative group was observed (P value: 0.015). Moreover, higher alanine aminotransferase (ALT) was observed in the in IgG positive group (P value: 0.02). In patients with positive IgM, relative hypocalcemia (median of 8.25; IQR: 8.02-8.62) was found which appeared to be significant (P value: 0.02).

CONCLUSION

This is the first largest study describing the SARS-CoV-2 seropositivity among children in Iran and provides important insight about the COVID-19 infection in children.

Association Between Age and Ethnicity with Pediatric Clinical Outcomes in COVID-2019

The novel coronavirus SARS-CoV-2 (COVID-19) has infected people across the world, including an increasing number of children in the United States (U.S.). The epidemiology of pediatric infection in the U.S. and how it influences clinical outcomes is still being characterized. In this study, we describe a cohort of 989 children with laboratory-confirmed SARS-CoV-2 infection. Children under age 20 in a statewide health system with SARS-CoV-2 infection, defined by positive PCR testing, between February 1 and August 30, 2020 were included in this observational cohort study. Data extracted from the medical record included age, demographic information, clinical illness severity, hospital stay, and comorbidities. Analysis included descriptive statistics and Chi-square as appropriate. Nine hundred and eighty-children met inclusion criteria for this study, ranging from 1 month to 20 years in age. Most children (62.4%) were asymptomatic at the time of diagnosis and children over the age of 2 were significantly more likely to be asymptomatic at diagnosis than younger children (P < .05). Hispanic children were significantly more likely to be symptomatic at the time of diagnosis (56.3% asymptomatic; P < .05). The high proportion of children with asymptomatic infection emphasizes the importance of understanding the unique role of children in the pandemic. Older children are more likely to be asymptomatic, but also more likely to experience severe or critical illness when symptoms do develop. Hispanic children were more likely to be symptomatic at diagnosis, highlighting the importance of culturally specific outreach to vulnerable communities.

Antiphospholipid antibodies in critically ill COVID-19 patients with thromboembolism: cause of disease or epiphenomenon?

Coronavirus 2019 disease (COVID-19) is associated with coagulation dysfunction that predisposes patients to an increased risk for both arterial (ATE) and venous thromboembolism (VTE) and consequent poor prognosis; in particular, the incidence of ATE and VTE in critically ill COVID-19 patients can reach 5% and 31%, respectively. The mechanism of thrombosis in COVID-19 patients is complex and still not completely clear. Recent literature suggests a link between the presence of antiphospholipid antibodies (aPLs) and thromboembolism in COVID-19 patients. However, it remains uncertain whether aPLs are an epiphenomenon or are involved in the pathogenesis of the disease.

Clinical-Pathological Correlation of the Pathophysiology and Mechanism of Action of COVID-19 - a Primer for Clinicians

PURPOSE OF REVIEW

Increasing knowledge of the pathogenesis of the SARS-CoV-2 infection and the complex interaction between host and viral factors have allowed clinicians to stratify the severity of COVID-19 infection. Epidemiological data has also helped to model viral carriage and infectivity. This review presents a comprehensive summary of the pathophysiology of COVID-19, the mechanisms of action of the SARS-CoV-2 virus, and the correlation with the clinical and biochemical characteristics of the disease.

RECENT FINDINGS

ACE2 and TMPRSS2 receptors have emerged as a key player in the mechanism of infection of SARS-CoV-2. Their distribution throughout the body has been shown to impact the organ-specific manifestations of COVID-19. The immune-evasive and subsequently immunoregulative properties of SARS-CoV-2 are also shown to be implicated in disease proliferation and progression. Information gleaned from the virological properties of SARS-CoV-2 is consistent with and reflects the clinical behavior of the COVID-19 infection. Further study of specific clinical phenotypes and severity classes of COVID-19 may assist in the development of targeted therapeutics to halt progression of disease from mild to moderate-severe. As the understanding of the pathophysiology and mechanism of action of SARS-CoV-2 continues to grow, it is our hope that better and more effective treatment options continue to emerge.

Clinical Profile and Risk Factors for Severe Disease in 402 Children Hospitalized with SARS-CoV-2 from India: Collaborative Indian Pediatric COVID Study Group

INTRODUCTION

There is a lack of large multicentric studies in children with COVID-19 from developing countries. We aimed to describe the clinical profile and risk factors for severe disease in children hospitalized with COVID-19 from India.

METHODS

In this multicentric retrospective study, we retrieved data related to demographic details, clinical features, including the severity of disease, laboratory investigations and outcome.

RESULTS

We included 402 children with a median (IQR) age of 7 (2-11) years. Fever was the most common symptom, present in 38.2% of children. About 44% had underlying comorbidity. The majority were asymptomatic (144, 35.8%) or mildly symptomatic (219, 54.5%). There were 39 (9.7%) moderate-severe cases and 13 (3.2%) deaths. The laboratory abnormalities included lymphopenia 25.4%, thrombocytopenia 22.1%, transaminitis 26.4%, low total serum protein 34.7%, low serum albumin 37.9% and low alkaline phosphatase 40%. Out of those who were tested, raised inflammatory markers were ferritin 58.9% (56/95), c-reactive protein 33.3% (41/123), procalcitonin 53.5% (46/86) and interleukin-6 (IL-6) 76%. The presence of fever, rash, vomiting, underlying comorbidity, increased total leucocyte count, thrombocytopenia, high urea, low total serum protein and raised c-reactive protein was factors associated with moderate to severe disease.

CONCLUSION

Fever was the commonest symptom. We identified additional laboratory abnormalities, namely lymphopenia, low total serum protein and albumin and low alkaline phosphatase. The majority of the children were asymptomatic or mildly symptomatic. We found high urea and low total serum protein as risk factors for moderate to severe disease for the first time.

Case Report: Acute Abdominal Pain as Presentation of Pneumonia and Acute Pancreatitis in a Pediatric Patient With COVID-19

Abdominal pain, nausea, and vomiting are known gastrointestinal symptoms of symptomatic SARS-CoV-2 infection (COVID-19 disease) in pediatric patients.¹ There is little literature regarding pancreatitis in COVID-19. We describe a 16-year-old male diagnosed with acute pancreatitis in the setting of a SARS-COV-2 infection and associated fluid balance considerations.

Pattern of Tobacco Use and Perceived Risk of COVID-19 Following Tobacco Use among the COVID-19 Patients of a Tertiary Health Care Institution in Eastern India

BACKGROUND

COVID-19 presented an unprecedented situation in which behavioural factors including tobacco use were believed to increase the risk of morbidity and mortality. The objective of the present study was to find the tobacco use pattern among the COVID-19 patients and the perceived risk of developing severe COVID-19 following tobacco use.

METHODS

This hospital-based, cross-sectional, analytical study was conducted among 300 COVID-19 patients at the All India Institute of Medical Sciences (AIIMS), Patna, India, during November and December 2020 using a semi-structured, pretested questionnaire. Descriptive and univariate analyses were performed using statistical software and the results were presented as proportion and percentage.

FINDINGS

About 27% and 16% of the COVID-19 patients were ever and current tobacco users, respectively. Quit attempts were found to have increased during the COVID-19 pandemic. A majority (65%) of current tobacco users had reduced their amount of tobacco use. Nearly 2 in every 3 patients perceived high risk of developing severe COVID-19 following tobacco use. Perceived risk was significantly higher among tobacco non-users, patients who were aware of the ill health effects of tobacco use, and patients who had noticed anti-tobacco messages or had been advised to quit tobacco. Among the current tobacco users, a significantly higher proportion of patients who perceived high risk of developing severe COVID-19 following tobacco use had made quit attempts or had reduced tobacco consumption during the pandemic (76.7% vs. 40%; P = 0.032).

CONCLUSION

A high proportion of COVID-19 patients believed that tobacco use aggravated the COVID-19 condition. Increased quit attempts and reduction in tobacco consumption during this pandemic is a positive sign for tobacco control.

The Many Faces of Innate Immunity in SARS-CoV-2 Infection

The innate immune system is important for initial antiviral response. SARS-CoV-2 can result in overactivity or suppression of the innate immune system. A dysregulated immune response is associated with poor outcomes; with patients having significant Neutrophil-to-Lymphocyte ratios (NLR) due to neutrophilia alongside lymphopenia. Elevated interleukin (IL)-6 and IL-8 leads to overactivity and is a prominent feature of severe COVID-19 patients. IL-6 can result in lymphopenia; where COVID-19 patients typically have significantly altered lymphocyte subsets. IL-8 attracts neutrophils; which may play a significant role in lung tissue damage with the formation of neutrophil extracellular traps leading to cytokine storm or acute respiratory distress syndrome. Several factors like pre-existing co-morbidities, genetic risks, viral pathogenicity, and therapeutic efficacy act as important modifiers of SARS-CoV-2 risks for disease through an interplay with innate host inflammatory responses. In this review, we discuss the role of the innate immune system at play with other important modifiers in SARS-CoV-2 infection.

Novel coronavirus disease 2019 (COVID-19) pandemic: From transmission to control with an interdisciplinary vision

There a lot of review papers addressing specific COVID-19 research sectors, then devoted to specialists. This review provides an in-depth summary of the available information about SARS-CoV-2 and the corresponding disease (also known as COVID-19), with a multi-disciplinary approach. After the paper introduction, the first section treats the virological characteristics of SARS-CoV-2, the medical implications of the infection, and the human susceptivity. Great attention is devoted to the factor affecting the infection routes, distinguishing among the possible human-to-human, environmental-to-human, and pollution-to-human transmission mechanisms. The second section is devoted to reporting the impact of SARS-CoV-2 not only on the healthcare systems but also on the economy and society. The third section is devoted to non-pharmaceutical behaviours against COVID-19. In this context, this review section presents an analysis of the European second wave allowing not only to focalize the importance of some restrictions, but also the relevance of social acceptance of some measures. The data reassumed in this work are very useful for interdisciplinary researchers that work in a team to find the basic available information about all the aspects connected with this pandemic (from virus diffusion mechanism to health information, from economic and social impacts to measures to reduce the pandemic spread), with great attention to social acceptance of restriction measures and of vaccines (that currently results to be insufficient to achieve community immunity). Then, this review paper highlights the fundamental role of the trans-multi-disciplinary research that is devoted not only to understand the basics of the pandemic to propose solutions but has also the commitment to find strategies to increase population resilience. For this aim, the authors strongly suggest the establishment of an international health-care trans-multi-disciplinary workforce devoted to investigate, mitigate, and control also future viral events.

Novel coronavirus disease 2019 (COVID-19) pandemic: From transmission to control with an interdisciplinary vision

There a lot of review papers addressing specific COVID-19 research sectors, then devoted to specialists. This review provides an in-depth summary of the available information about SARS-CoV-2 and the corresponding disease (also known as COVID-19), with a multi-disciplinary approach. After the paper introduction, the first section treats the virological characteristics of SARS-CoV-2, the medical implications of the infection, and the human susceptivity. Great attention is devoted to the factor affecting the infection routes, distinguishing among the possible human-to-human, environmental-to-human, and pollution-to-human transmission mechanisms. The second section is devoted to reporting the impact of SARS-CoV-2 not only on the healthcare systems but also on the economy and society. The third section is devoted to non-pharmaceutical behaviours against COVID-19. In this context, this review section presents an analysis of the European second wave allowing not only to focalize the importance of some restrictions, but also the relevance of social acceptance of some measures. The data reassumed in this work are very useful for interdisciplinary researchers that work in a team to find the basic available information about all the aspects connected with this pandemic (from virus diffusion mechanism to health information, from economic and social impacts to measures to reduce the pandemic spread), with great attention to social acceptance of restriction measures and of vaccines (that currently results to be insufficient to achieve community immunity). Then, this review paper highlights the fundamental role of the trans-multi-disciplinary research that is devoted not only to understand the basics of the pandemic to propose solutions but has also the commitment to find strategies to increase population resilience. For this aim, the authors strongly suggest the establishment of an international health-care trans-multi-disciplinary workforce devoted to investigate, mitigate, and control also future viral events.

Coronavirus disease 2019 respiratory disease in children: clinical presentation and pathophysiology

PURPOSE OF REVIEW

Pediatric coronavirus disease 2019 (COVID-19) respiratory disease is a distinct entity from adult illness, most notable in its milder phenotype. This review summarizes the current knowledge of the clinical patterns, cellular pathophysiology, and epidemiology of COVID-19 respiratory disease in children with specific attention toward factors that account for the maturation-related differences in disease severity.

RECENT FINDINGS

Over the past 14 months, knowledge of the clinical presentation and pathophysiology of COVID-19 pneumonia has rapidly expanded. The decreased disease severity of COVID-19 pneumonia in children was an early observation. Differences in the efficiency of viral cell entry and timing of immune recognition and response between children and adults remain at the center of ongoing research.

SUMMARY

The clinical spectrum of COVID-19 respiratory disease in children is well defined. The age-related differences protecting children from severe disease and death remain incompletely understood.

Gastrointestinal Manifestations of Pediatric Coronavirus Disease and Their Relationship with a Severe Clinical Course: A Systematic Review and Meta-analysis

BACKGROUND

Data on the gastrointestinal (GI) manifestations of Pediatric Corona Virus Disease (COVID-19) are conflicting and the relationship between GI involvement and the severity of COVID-19 disease has not been evaluated. The objectives of this systematic review were to determine the GI manifestations of pediatric COVID-19 and to evaluate their role as risk factors for a severe clinical course.

METHODS

: A systematic literature search was carried out in PubMed and Scopus for studies published before 31 December 2020 with information about the GI manifestations of pediatric COVID-19. Patients with a severe and nonsevere clinical course were compared using the inverse variance heterogeneity model and odds ratio (OR) as the effect size. A sensitivity analysis was performed if the heterogeneity was high among studies.

RESULTS

A total of 811 studies were identified through a systematic search of which 55 studies (4369 patients) were included in this systematic review. The commonest GI symptoms were diarrhea-19.08% [95% confidence interval (CI) 10.6-28.2], nausea/vomiting 19.7% (95% CI 7.8-33.2) and abdominal pain 20.3% (95% CI 3.7-40.4). The presence of diarrhea was significantly associated with a severe clinical course with a pooled OR of 3.97 (95% CI 1.80-8.73; p < 0.01). Abdominal pain and nausea/vomiting were not associated with disease severity.

CONCLUSIONS

Diarrhea, nausea/vomiting or abdominal pain are present in nearly one-fifth of all children with COVID-19. The presence of diarrhea portends a severe clinical course.

Understanding COVID-19: are children the key?

The devastating impact of the COVID-19 pandemic on global health and economic stability is immeasurable. The situation is dynamic and fast-evolving, with the world facing new variants of concern which may have immune escape potential. With threatened treatment and preventative strategies at stake, and the prospect of reinfection prolonging the pandemic, it is more crucial than ever to understand the pathogenesis of SARS-CoV-2 infection, which intriguingly disproportionately affects adults and the elderly. Children infected with SARS-CoV-2 remain largely asymptomatic or undergo a transient mild illness. Understanding why children have a milder phenotype and a significant survival advantage may help identify modifiable risk factors in adults. Current evidence suggests adults with COVID-19 show variability in innate and adaptive immune responses, which result in uncontrolled proinflammatory cytokine production in some patients, leading to severe disease and mortality. Children with acute COVID-19 infection seldom progress to acute respiratory distress syndrome and are less likely to exhibit the cytokine storm which is so prominent in adults. Even with the Kawasaki-like illness, a hyperinflammation syndrome also known as paediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2, mortality is low. The key to successfully combating SARS-CoV-2 and future zoonotic pandemics may lie in understanding these critical differences and merits focused consideration and research. The impact of community transmission among asymptomatic children is unknown; sustained global decline in infection rates and control of the COVID-19 pandemic may not be achieved until vaccination of children occurs. In this review, we discuss the fundamental differences in the immune response between children and adults in the fight against SARS-CoV-2.

Pediatric Coronavirus Disease 2019: Clinical Features and Management

There is a lack of clarity regarding management of COVID-19 infection in children. This review aims to summarize the key clinical presentations and management of Pediatric COVID-19. The Medline database was searched for seminal articles and guidelines on COVID-19 presentation and management in children less than 18 years of age. COVID-19 has a lower incidence (1-5% of reported cases worldwide), causes milder disease with lower need for intensive care admission and lower mortality rate (0-0.7%) in children compared with adults. Multisystem inflammatory syndrome is a rare but severe complication in children. Majority of patients require supportive care including adequate hydration, nutrition and antipyretics. Supplemental oxygen therapy should be given in moderate to severe cases with all precautions to prevent air-borne COVID-19 spread. Steroids may be helpful in severe cases. Anticoagulation is indicated in moderate to severe cases with risk factors. More data on the efficacy and safety of antivirals and immunomodulators in children is needed.

COVID-19 Pandemic and Remote Education Contributes to Improved Nutritional Behaviors and Increased Screen Time in a Polish Population-Based Sample of Primary School Adolescents: Diet and Activity of Youth during COVID-19 (DAY-19) Study

The Coronavirus-19 disease (COVID-19) pandemic has influenced the nutrition of individuals, including the diet followed, food availability, and food security. However, thus far, only a few studies have been published regarding the diet and activity of children and adolescents. The aim of the present study was to analyze the influence of the COVID-19 pandemic and remote education in this period on the diet and physical activity in a Polish population-based sample of primary school adolescents. In June 2020, the Diet and Activity of Youth during COVID-19 (DAY-19) Study was conducted on a population recruited based on stratified random sampling from all regions (schools sampled from counties, and counties from voivodeships). The sample consisted of a total of 1334 adolescents aged 10–16 years. The study assessed the diet and physical activity of the participants using a validated questionnaire which included questions about the period of remote education and the period before the COVID-19 pandemic. The participants were asked about the following: consumption of fruit, vegetables, soft drinks, water, French fries, and fast food; eating meals in front of the television; and the number of days they are physically active and the number of hours they spend watching television. The obtained data were analyzed by stratifying the respondents by the gender, age, size of the city and total COVID-19 morbidity in the voivodeship. It was observed that, during the pandemic and the resultant remote education, the proportion of respondents who declared the recommended intake of fruits and vegetables had increased compared to that before the pandemic—a higher proportion consumed at least three portions of fruit per day (19.0% before pandemic vs. 27.4% during pandemic; p < 0.0001), as well as three and four or more portions of vegetables per day (11.9% vs. 14.5% and 7.5% vs. 11.1%; p = 0.0004). At the same time, the proportion of respondents consuming at least three cups of water per day had increased (41.1% vs. 47.9%; p = 0.0020), whereas the proportion of respondents who never or rarely eat their meals in front of the television had decreased (35.6% vs. 28.9%; p < 0.0001), and the proportion watching television for more than 2 h a day had increased (78.3% vs. 88.4%; p < 0.0001). Based on the results, it may be concluded that, during the period of remote education due to the COVID-19 pandemic, the dietary behaviors of the studied population of Polish adolescents were more beneficial, which included a higher intake of fruit, vegetables, and water, compared to before the pandemic. In spite of the increasing screen time, including eating in front of the television, there was no reduction in the number of days the respondents were physically active.

Effectiveness of Booster Measles-Mumps-Rubella Vaccination in Lower COVID-19 Infection Rates: A Retrospective Cohort Study in Turkish Adults

Objective

The aim of this study was to investigate the effectiveness of booster vaccination of adults with measles-mumps-rubella in the COVID-19 infection rates.

Methods

In order to investigate this hypothesis, we tested COVID-19 positivity rate through PCR assay on the participants (n=245; male), who had to share the same student accommodation together with the same dining hall to provide governmental service. Participants were divided into two groups based on their booster vaccination status with measles-mumps-rubella: the non-vaccinated group (n=207) and the vaccinated group (n=38). The rate of COVID-19 seropositivity, age, body mass index (BMI), active smoking and presence of comorbidity were also measured and recorded.

Results

All of the participants were healthy, and age distribution, comorbidity rates, active smoking status and BMI did not vary significantly among the two groups (p=0.305, p=0.594, p=0.280, and p=0.922, respectively). About 36.7% (n=90) of the participants were found to be COVID-19 positive by PCR among which the non-vaccinated cases had higher rates of COVID-19 seropositivity than the vaccinated cases (40.6% vs 15.8%) (OR=3.6, 95%CI: 1.5–9.0, p=0.004).

Conclusion

Based on these results, we cautiously predict that immunity produced by MMR vaccination boosters may provide some degree of protection against COVID-19 in the adult population.

Pediatric Coronavirus Disease 2019: Clinical Features and Management

There is a lack of clarity regarding management of COVID-19 infection in children. This review aims to summarize the key clinical presentations and management of Pediatric COVID-19. The Medline database was searched for seminal articles and guidelines on COVID-19 presentation and management in children less than 18 years of age. COVID-19 has a lower incidence (15% of reported cases worldwide), causes milder disease with lower need for intensive care admission and lower mortality rate (00.7%) in children compared with adults. Multisystem inflammatory syndrome is a rare but severe complication in children. Majority of patients require supportive care including adequate hydration, nutrition and antipyretics. Supplemental oxygen therapy should be given in moderate to severe cases with all precautions to prevent air-borne COVID-19 spread. Steroids may be helpful in severe cases. Anticoagulation is indicated in moderate to severe cases with risk factors. More data on the efficacy and safety of antivirals and immunomodulators in children is needed.

An autopsy study of the spectrum of severe COVID-19 in children: From SARS to different phenotypes of MIS-C

BACKGROUND

COVID-19 in children is usually mild or asymptomatic, but severe and fatal paediatric cases have been described. The pathology of COVID-19 in children is not known; the proposed pathogenesis for severe cases includes immune-mediated mechanisms or the direct effect of SARS-CoV-2 on tissues. We describe the autopsy findings in five cases of paediatric COVID-19 and provide mechanistic insight into the mechanisms involved in the pathogenesis of the disease.

METHODS

Children and adolescents who died with COVID-19 between March 18 and August 15, 2020 were autopsied with a minimally invasive method. Tissue samples from all vital organs were analysed by histology, electron microscopy (EM), reverse-transcription polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC).

FINDINGS

Five patients were included, one male and four female, aged 7 months to 15 years. Two patients had severe diseases before SARS-CoV-2 infection: adrenal carcinoma and Edwards syndrome. Three patients were previously healthy and had multisystem inflammatory syndrome in children (MIS-C) with distinct clinical presentations: myocarditis, colitis, and acute encephalopathy with status epilepticus. Autopsy findings varied amongst patients and included mild to severe COVID-19 pneumonia, pulmonary microthrombosis, cerebral oedema with reactive gliosis, myocarditis, intestinal inflammation, and haemophagocytosis. SARS-CoV-2 was detected in all patients in lungs, heart and kidneys by at least one method (RT-PCR, IHC or EM), and in endothelial cells from heart and brain in two patients with MIS-C (IHC). In addition, we show for the first time the presence of SARS-CoV-2 in the brain tissue of a child with MIS-C with acute encephalopathy, and in the intestinal tissue of a child with acute colitis. Interpretation: SARS-CoV-2 can infect several cell and tissue types in paediatric patients, and the target organ for the clinical manifestation varies amongst individuals. Two major patterns of severe COVID-19 were observed: a primarily pulmonary disease, with severe acute respiratory disease and diffuse alveolar damage, or a multisystem inflammatory syndrome with the involvement of several organs. The presence of SARS-CoV-2 in several organs, associated with cellular ultrastructural changes, reinforces the hypothesis that a direct effect of SARS-CoV-2 on tissues is involved in the pathogenesis of MIS-C.

FUNDING

Fundação de Amparo à Pesquisa do Estado de São Paulo, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Bill and Melinda Gates Foundation.

SARS-COV-2 infection in pregnant women and newborns in a Spanish cohort (GESNEO-COVID) during the first wave

BACKGROUND

Knowledge about SARS-CoV-2 infection in pregnancy and newborns is scarce. The objective of this study is to analyse clinical and epidemiological characteristics of a cohort of women infected with SARS-CoV-2 during pregnancy and their newborns exposed to SARS-CoV-2 during gestation.

METHODS

Multicentric observational study of Spanish hospitals from the GESNEO-COVD cohort, participants in RECLIP (Spanish Network of Paediatric Clinical Assays). Women with confirmed SARS-CoV-2 infection by PCR and/or serology during pregnancy, diagnosed and delivering during the period 15/03/2020-31/07/2020 were included. Epidemiological, clinical, and analytical data was collected.

RESULTS

A total of 105 pregnant women with a median of 34.1 years old (IQR: 28.8-37.1) and 107 newborns were included. Globally, almost 65% of pregnant women had some COVID-19 symptoms and more than 43% were treated for SARS-COV-2. Overall, 30.8% of pregnant women had pneumonia and 5 (4.8%) women were admitted to the intensive care unit needing invasive mechanical ventilation. There was a rate of 36.2% of caesarean sections, which was associated with pneumonia during pregnancy (OR: 4.203, CI 95%: 1.473-11.995) and lower gestational age at delivery (OR: 0.724, CI 95%: 0.578-0.906). The prevalence of preterm birth was 20.6% and prematurity was associated with pneumonia during gestation (OR: 6.970, CI95%: 2.340-22.750) and having a positive SARS-CoV-2 PCR at delivery (OR: 6.520, CI95%: 1.840-31.790). All nasopharyngeal PCR in newborns were negative at birth and one positivized at 15 days of life. Two newborns died, one due to causes related to prematurity and another of unexpected sudden death during early skin-to-skin contact after delivery.

CONCLUSIONS

Although vertical transmission has not been reported in this cohort, the prognosis of newborns could be worsened by SARS-CoV-2 infection during pregnancy as COVID-19 pneumonia increased the risk of caesarean section deliveries and preterm births.

COVID-19 pneumonia successfully managed with high-flow nasal cannula in a 15-year-old boy

We report an otherwise healthy, fully immunised 15-year-old boy who was transferred to our Pediatric intensive care unit with 4 days of fever, dry cough, increased work of breathing and impending respiratory failure. Two days prior, amoxicillin/clavulanic acid was prescribed for lower airway symptoms resembling pneumonia. PCR of the nasopharyngeal swab revealed an active COVID-19 infection (Ct 19). The CT scan showed significant ground-glass opacities highly associated with COVID-19 (COVID-19 reporting and data system 4). Antibiotics were continued and chloroquine was given for 5 days. High-flow nasal cannula (HFNC) was started as respiratory support therapy with rapid decrease of tachypnoea and oxygen demand. HFNC was successfully stopped after 7 days. The patient made full clinical recovery. This case illustrates HFNC as a successful respiratory support therapy in a paediatric patient with an active COVID-19 pneumonia.

Risk factors for developing severe COVID-19 in China: an analysis of disease surveillance data

BACKGROUND

COVID-19 has posed an enormous threat to public health around the world. Some severe and critical cases have bad prognoses and high case fatality rates, unraveling risk factors for severe COVID-19 are of significance for predicting and preventing illness progression, and reducing case fatality rates. Our study focused on analyzing characteristics of COVID-19 cases and exploring risk factors for developing severe COVID-19.

METHODS

The data for this study was disease surveillance data on symptomatic cases of COVID-19 reported from 30 provinces in China between January 19 and March 9, 2020, which included demographics, dates of symptom onset, clinical manifestations at the time of diagnosis, laboratory findings, radiographic findings, underlying disease history, and exposure history. We grouped mild and moderate cases together as non-severe cases and categorized severe and critical cases together as severe cases. We compared characteristics of severe cases and non-severe cases of COVID-19 and explored risk factors for severity.

RESULTS

The total number of cases were 12 647 with age from less than 1 year old to 99 years old. The severe cases were 1662 (13.1%), the median age of severe cases was 57 years [Inter-quartile range(IQR): 46-68] and the median age of non-severe cases was 43 years (IQR: 32-54). The risk factors for severe COVID-19 were being male [adjusted odds ratio (aOR) = 1.3, 95% CI: 1.2-1.5]; fever (aOR = 2.3, 95% CI: 2.0-2.7), cough (aOR = 1.4, 95% CI: 1.2-1.6), fatigue (aOR = 1.3, 95% CI: 1.2-1.5), and chronic kidney disease (aOR = 2.5, 95% CI: 1.4-4.6), hypertension (aOR = 1.5, 95% CI: 1.2-1.8) and diabetes (aOR = 1.96, 95% CI: 1.6-2.4). With the increase of age, risk for the severity was gradually higher [20-39 years (aOR = 3.9, 95% CI: 1.8-8.4), 40-59 years (aOR = 7.6, 95% CI: 3.6-16.3), ≥ 60 years (aOR = 20.4, 95% CI: 9.5-43.7)], and longer time from symtem onset to diagnosis [3-5 days (aOR = 1.4, 95% CI: 1.2-1.7), 6-8 days (aOR = 1.8, 95% CI: 1.5-2.1), ≥ 9 days(aOR = 1.9, 95% CI: 1.6-2.3)].

CONCLUSIONS

Our study showed the risk factors for developing severe COVID-19 with large sample size, which included being male, older age, fever, cough, fatigue, delayed diagnosis, hypertension, diabetes, chronic kidney diasease, early case identification and prompt medical care. Based on these factors, the severity of COVID-19 cases can be predicted. So cases with these risk factors should be paid more attention to prevent severity.

Acute and chronic exposure to air pollution in relation with incidence, prevalence, severity and mortality of COVID-19: a rapid systematic review

BACKGROUND

Air pollution is one of the world's leading mortality risk factors contributing to seven million deaths annually. COVID-19 pandemic has claimed about one million deaths in less than a year. However, it is unclear whether exposure to acute and chronic air pollution influences the COVID-19 epidemiologic curve.

METHODS

We searched for relevant studies listed in six electronic databases between December 2019 and September 2020. We applied no language or publication status limits. Studies presented as original articles, studies that assessed risk, incidence, prevalence, or lethality of COVID-19 in relation with exposure to either short-term or long-term exposure to ambient air pollution were included. All patients regardless of age, sex and location diagnosed as having COVID-19 of any severity were taken into consideration. We synthesised results using harvest plots based on effect direction.

RESULTS

Included studies were cross-sectional (n = 10), retrospective cohorts (n = 9), ecological (n = 6 of which two were time-series) and hypothesis (n = 1). Of these studies, 52 and 48% assessed the effect of short-term and long-term pollutant exposure, respectively and one evaluated both. Pollutants mostly studied were PM2.5 (64%), NO2 (50%), PM10 (43%) and O3 (29%) for acute effects and PM2.5 (85%), NO2 (39%) and O3 (23%) then PM10 (15%) for chronic effects. Most assessed COVID-19 outcomes were incidence and mortality rate. Acutely, pollutants independently associated with COVID-19 incidence and mortality were first PM2.5 then PM10, NO2 and O3 (only for incident cases). Chronically, similar relationships were found for PM2.5 and NO2. High overall risk of bias judgments (86 and 39% in short-term and long-term exposure studies, respectively) was predominantly due to a failure to adjust aggregated data for important confounders, and to a lesser extent because of a lack of comparative analysis.

CONCLUSION

The body of evidence indicates that both acute and chronic exposure to air pollution can affect COVID-19 epidemiology. The evidence is unclear for acute exposure due to a higher level of bias in existing studies as compared to moderate evidence with chronic exposure. Public health interventions that help minimize anthropogenic pollutant source and socio-economic injustice/disparities may reduce the planetary threat posed by both COVID-19 and air pollution pandemics.

The Impact of Positive Youth Development Attributes on Posttraumatic Stress Disorder Symptoms Among Chinese Adolescents Under COVID-19

PURPOSE

This study examined the prevalence of posttraumatic stress disorder (PTSD) symptoms among adolescents in mainland China under COVID-19. The direct effects of the perceived threat of COVID-19 and positive youth development (PYD) qualities, as well as the moderating effect of PYD qualities on PTSD symptoms, were studied.

METHODS

Five schools in Chengdu, Sichuan, China, participated in this study. Two waves of data were collected before school lockdown (Wave 1, between December 2019 and January 2020) and after school resumption (Wave 2, between June 2020 and July 2020), respectively. A total of 4,981 adolescents aged above 11 years (Mean age = 13.15, SD = 1.32 at Wave 1, 51.5% girls) completed questionnaires at both waves. Students responded to measures of PYD qualities at both waves and perceived threat and PTSD symptoms at Wave 2.

RESULTS

A total of 517 adolescents (10.4%) could be regarded as having PTSD. Results indicated significant unique main effects of perceived threat (β = .13, p < .001) and Wave 1 PYD qualities (β = -.16, p < .001) on PTSD symptoms. Besides, results showed a significant moderating effect of PYD qualities in mitigating the negative impact of perceived threat on PTSD symptoms.

CONCLUSIONS

This study revealed the protective effect of PYD attributes in reducing the negative influence of traumatic situations such as COVID-19 on adolescent mental health. Results underscore the importance of promoting PYD qualities in adolescents in mainland China via effective PYD programs.

Clinical characteristic and epidemiological features of SARS CoV-2 disease patients from a COVID-19 designated hospital in New Delhi

Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) infection is rapidly evolving as a serious global pandemic. The present study describes the clinical characteristics of SARS CoV-2 infection patients. The samples were subjected to reverse-transcription polymerase chain reaction or Rapid Antigen test for diagnosis of SARS CoV-2. A cohort of 3745 patients with confirmed diagnosis of SARS CoV-2 infection in a tertiary care center in New Delhi, India were included in this study. Data were collected from offline and online medical records over a period of 6 months. Amongst 3745 SARS CoV-2 infected patients, 2245 (60%) were symptomatic and 1500 (40%) were asymptomatic. Most common presenting symptom was cough (49.3%) followed febrile episodes (47.1%), breathlessness (42.7%), and sore throat (35.1%). Cough along with breathlessness (24.1) was the most common combination of symptoms followed by fever with cough (22.7). The most common comorbidity found among symptomatic group was diabetes (42.5%) followed by hypertension (21.4%) and chronic kidney disease (18%). Comorbidities like diabetes mellitus, chronic diseases of lungs, heart, and kidneys were found to be common in symptomatic group and this was found to be statistically significant (p < .05). COVID-19 is an evolving disease and data from our study help in understanding the clinic-epidemiological profile of patients.

A family case of COVID-19 pneumonia with different chest CT features and duration of SARS-CoV-2 shedding: a case report from Japan

Coronavirus disease 2019 (COVID-19) pneumonia in children characteristically has a milder clinical presentation, with milder inflammatory biomarkers and radiological findings. Accumulating evidence indicates a difference in chest computed tomography (CT) features and duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding between children and adults. Here, we report a family case of COVID-19 pneumonia in which two brothers (age 14 years and 2 years) had different findings. On admission, the 2-year-old had few symptoms with no sign of pneumonia, whereas the older brother had presented with pneumonia on admission. Both were positive for SARS-CoV-2 infection on polymerase chain reaction. They both had obvious characteristic signs of COVID-19 pneumonia on chest CT. However, CT findings in the younger brother were non-specific and similar to other pneumonias. The older brother required longer treatment because of a longer shedding period of SARS-CoV-2 detected in nasopharyngeal samples. Both boys were discharged without complications. This family case suggests that the clinical features of COVID-19 pneumonia might differ between younger and older children.

The Relationship between COVID-19 and Innate Immunity in Children: A Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the pandemic viral pneumonia that was first identified in Wuhan, China, in December 2019, and has since rapidly spread around the world. The number of COVID-19 cases recorded in pediatric age is around 1% of the total. The immunological mechanisms that lead to a lower susceptibility or severity of pediatric patients are not entirely clear. At the same time, the immune dysregulation found in those children who developed the multisystem inflammatory syndrome (MIC-S) is not yet fully understood. The aim of this review is to analyze the possible influence of children's innate immune systems, considering the risk of contracting the virus, spreading it, and developing symptomatic disease or complications related to infection.

COVID-19 in Children: Respiratory Involvement and Some Differences With the Adults

The coronavirus disease 2019 (COVID-19) represents a health problem with multidimensional impacts and heterogeneous respiratory involvement in children, probably due to the interaction between different and complex mechanisms that could explain its variable degrees of severity. Although the majority of reports reveal that children develop less severe cases, the number of patients is increasing with more morbidity. Most serious respiratory manifestations are acute respiratory distress syndrome (ARDS) and pneumonia. By understanding the key aspects that can be used to differentiate between pediatric and adult respiratory compromise by COVID-19, we can improve our knowledge, and thus decrease the negative impact of the disease in the pediatric population. In this mini review, we summarize some of the mechanisms and findings that distinguish between adult and pediatric COVID-19 and respiratory involvement, taking into account some issues related to the physiopathology, diagnosis, clinical and paraclinical presentation, severity, treatment, and control of the disease.

Modeling Predictive Age-Dependent and Age-Independent Symptoms and Comorbidities of Patients Seeking Treatment for COVID-19: Model Development and Validation Study

Background

The COVID-19 pandemic continues to ravage and burden hospitals around the world. The epidemic started in Wuhan, China, and was subsequently recognized by the World Health Organization as an international public health emergency and declared a pandemic in March 2020. Since then, the disruptions caused by the COVID-19 pandemic have had an unparalleled effect on all aspects of life.

Objective

With increasing total hospitalization and intensive care unit admissions, a better understanding of features related to patients with COVID-19 could help health care workers stratify patients based on the risk of developing a more severe case of COVID-19. Using predictive models, we strive to select the features that are most associated with more severe cases of COVID-19.

Methods

Over 3 million participants reported their potential symptoms of COVID-19, along with their comorbidities and demographic information, on a smartphone-based app. Using data from the >10,000 individuals who indicated that they had tested positive for COVID-19 in the United Kingdom, we leveraged the Elastic Net regularized binary classifier to derive the predictors that are most correlated with users having a severe enough case of COVID-19 to seek treatment in a hospital setting. We then analyzed such features in relation to age and other demographics and their longitudinal trend.

Results

The most predictive features found include fever, use of immunosuppressant medication, use of a mobility aid, shortness of breath, and severe fatigue. Such features are age-related, and some are disproportionally high in minority populations.

Conclusions

Predictors selected from the predictive models can be used to stratify patients into groups based on how much medical attention they are expected to require. This could help health care workers devote valuable resources to prevent the escalation of the disease in vulnerable populations.

Immunity to SARS-CoV-2: Lessons Learned

In the year since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and with understanding of the etiology of the coronavirus disease 2019 (COVID-19) pandemic, it has become clear that most infected individuals achieve some form of immunity against the virus with relatively few reported reinfections. A number of vaccines have already achieved emergency use authorization based on data from large phase 3 field efficacy clinical trials. However, our knowledge about the extent and durability of this immunity, and the breadth of vaccine coverage against SARS-CoV-2 variants is still evolving. In this narrative review, we summarize the latest and rapidly developing understanding of immunity to SARS-CoV-2 infection, including what we have learned about the key antigens of SARS-CoV-2 (i.e., the spike protein and its receptor-binding domain), their importance in vaccine development, the immediate immune response to SARS-CoV-2, breadth of coverage of emerging SARS-CoV-2 variants, contributions of preexisting immunity to related coronaviruses, and duration of immunity. We also discuss lessons from newer approaches, such as systems serology, that provide insights into molecular and cellular immune responses elicited and how they relate to the trajectory of infection, and potentially inform immune correlates of protection. We also briefly examine the limited research literature on immune responses in special populations, such as pregnant women and children.

COVID-19: Risk Factors Associated with Infectivity and Severity

COVID‐19 is highly transmissible; however, its severity varies from one individual to another. Variability among different isolates of the virus and among its receptor (ACE2) may contribute to this severity, but comorbidity plays a major role on disease prognosis. Many comorbidities have been reported to be associated with severe COVID‐19 patients. We have collected data from retrospective studies which include clinical and epidemiological features of patients and categorize them into severe/mild, ICU/non‐ICU and survivors/dead patients. In this review, we give an update about SARS‐CoV‐2 structure with emphasis on the possible reasons for the severity of the virus in patients. We also collected information and patients’ data to highlight the relation between COVID‐19 patients and comorbidities.

Perspectives and Challenges in the Fight Against COVID-19: The Role of Genetic Variability

In the last year, the advent of the COVID-19 pandemic brought a new consideration for the multidisciplinary sciences. The unknown mechanisms of infection used by SARS-CoV-2 and the absence of effective antiviral pharmacological therapy, diagnosis methods, and vaccines evoked scientific efforts on the COVID-19 outcome. In general, COVID-19 clinical features are a result of local and systemic inflammatory processes that are enhanced by some preexistent comorbidities, such as diabetes, obesity, cardiovascular, and pulmonary diseases, and biological factors, like gender and age. However, the discrepancies in COVID-19 clinical signs observed among those patients lead to investigations about the critical factors that deeply influence disease severity and death. Herein, we present the viral infection mechanisms and its consequences after blocking the angiotensin-converting enzyme 2 (ACE2) axis in different tissues and the progression of inflammatory and immunological reactions, especially the influence of genetic features on those differential clinical responses. Furthermore, we discuss the role of genotype as an essential indicator of COVID-19 susceptibility, considering the expression profiles, polymorphisms, gene identification, and epigenetic modifications of viral entry factors and their recognition, as well as the infection effects on cell signaling molecule expression, which amplifies disease severity.

COVID-19 in Children With Liver Disease

Background: The global pandemic caused by novel Coronavirus SARS-CoV-2 disease (COVID-19) is a major threat to the general population and for patients with pre-existing chronic conditions. We report data concerning SARS-CoV-2 infection in children with chronic liver disease (CLD). Methods: A literature review using the online database PubMed was performed to summarize available findings on the association between pre-existing liver disease and COVID-19 infection in children. Results: Children with COVID-19 have preserved effector and immunosuppressive components resulting in a milder disease compared to adults. The most common hepatic manifestation is an elevation of hepatic transaminases. Liver damage may be directly caused by viral infection of liver cells, by medications or by the chronic hypoxia seen in COVID-19 patients. A multicenter study reported that the majority of children with a CLD remained healthy during the outbreak. Similarly, studies reported that children on immunosuppressive treatment, including patients with autoimmune liver disease (AILD) and liver transplantation (LT), maintained good health during the outbreak without experiencing major complications even if infected with COVID-19. Conclusion: COVID-19-related liver injury presents with a mild elevation of transaminases, although its clinical significance is unclear. Children with CLD, including those with AILD and post-LT, do not have an increased risk for severe disease course of SARS-CoV-2 infection with little or no liver dysfunction. These data highlight the necessity to ensure normal standards of care while adhering to national Covid-19 guidelines, and particularly to maintain immunosuppressive medication to prevent relapse or rejection. Further research is required to evaluate the differences in clinical course between immunosuppressed adults and children and in particular whether asymptomatic infection is a concern.

Age cohorts stratified according to age-distributions of COVID-19 morbidity statistics identify uniquely age-dependent CD3+CD8+ T-cell lymphocytopenia in COVID-19 patients without comorbidities on admission

If age boundaries are arbitrarily or roughly defined, age-related analyses can result in questionable findings. Here, we aimed to delineate the uniquely age-dependent immune features of coronavirus disease 2019 (COVID-19) in a retrospective study of 447 patients, stratified according to age distributions of COVID-19 morbidity statistics into well-defined age-cohorts (2–25y, 26–38y, 39–57y, 58–68y, and 69–79y). Age-dependent susceptibilities and severities of the disease were observed in COVID-19 patients. A comparison of the lymphocyte counts among the five age-groups indicated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection led to age-dependent lymphopenia. Among the lymphocyte subsets, the CD8⁺ T cell count alone was significantly and age-dependently decreased (520, 385, 320, 172, and 139 n/μl in the five age-groups, respectively). In contrast, the CD4⁺ T cell, B cell, and natural killer cell counts did not differ among age-cohorts. Age and CD8⁺ T cell counts (r=‒0.435, p<0.0001) were negatively correlated in COVID-19 patients. Moreover, SARS-CoV-2 infection age-dependently increased the plasma C-reactive protein concentrations (2.0, 5.0, 9.0, 11.6, and 36.1 mg/L in the five age-groups, respectively). These findings can be used to elucidate the role of CD8⁺ T cells in age-related pathogenesis and to help develop therapeutic strategies for COVID-19.

COVID-19: Why does disease severity vary among individuals?

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is responsible for the current pandemic, coronavirus disease 2019 (COVID-19). While all people are susceptible to the SARS-CoV-2 infection, the nature and severity of the disease vary significantly among individuals and populations. Importantly, reported disease burdens and case fatality rates differ considerably from country to country. There are, however, still uncertainties about the severity of the disease among individuals or the reason behind a more severe disease in some cases. There is a strong possibility that the severity of this disease depends on a complicated interaction between the host, virus, and environment, which leads to different clinical outcomes. The objective of this article is to point out the essential influential factors related to the host, virus, and environment affecting the clinical outcome of COVID-19.

Distinct Characteristics of COVID-19 Infection in Children

SARS-CoV-2, a member of the family coronaviridae, has triggered a lethal pandemic termed coronavirus disease 2019 (COVID-19). Pediatric patients, mainly from families with a cluster of infection or a history of exposure to epidemic areas, get infected via direct contacts or air-borne droplets. Children (aged below 18 years) are susceptible to COVID-19, with an average incubation period of about 6.5 days. Most cases present asymptomatic or common cold symptoms such as fever, cough, and myalgia or fatigue, which is milder than adult patients. Besides, most abnormal laboratory and radiologic findings in children with COVID-19 are non-specific. Since no specific chemotherapeutic agents have been approved for children, timely preventive methods could effectively forestall the transmission of SARS-CoV-2. To date, mostly studied cases have been adults with COVID-19, whereas data on pediatrics patients remain poorly defined. We herein conducted a literature review for papers published in PubMed and medRxiv (preprints) between December 2019 and December 2020 that reported on pediatrics patients (aged below 18 years) with a confirmed COVID-19 diagnosis. In this review, we summarized and discussed the pathogenesis, epidemiology, and clinical management of COVID-19 in pediatrics patients to improve our understanding of this new disease in children.

Clinical characteristics and evolution of pediatric patients with acute leukemia and SARS-COV2 virus infection in a third level hospital in Mexico

Introduction

Reports have revealed that people susceptible to severe forms of COVID-19 are older adults with comorbidities; However, the pediatric population has also been affected, considering children with underlying conditions such as onco-hematological conditions to be high risk. We present a cases series in a third level hospital.

Material and methods

We conducted a retrospective study in children under the age of 16 years with a diagnosis of acute leukemia and infection with the SARS-CoV2 virus. Descriptive statistics with means and percentages were used. To show differences between the groups, Chi-square test, Student t test and Mann-Whitney U test were used depending on the type of variable and its distribution.

Results

SARS-CoV2 virus infection was confirmed in 15 children diagnosed with acute leukemia, at different stages of treatment. The mean age was 7.5 years, 8 male and 7 female, 11 of them diagnosed with acute B-cell lymphoblastic leukemia, one with acute T-cell lymphoblastic leukemia and 3 with acute myeloid leukemia. The mean days of hospital stay at the diagnosis of COVID-19 was 22. Thirteen of the children had fever and neutropenia. 7 patients died. There was a statistically significant correlation with the outcome in patients who presented a prolongation of aPTT, an increase in D-dimer, an increase in liver enzymes and severe respiratory distress with the need for mechanical ventilation.

Conclusion

The risk of death in children with leukemia and COVID-19 was associated with prolonged aPTT, increased D-dimer, increased liver enzymes, respiratory distress, and the need for mechanical ventilation.

Association of Age With SARS-CoV-2 Antibody Response

Importance

Accumulating evidence suggests that children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more likely to manifest mild symptoms and are at a lower risk of developing severe respiratory disease compared with adults. It remains unknown how the immune response in children differs from that of adolescents and adults.

Objective

To investigate the association of age with the quantity and quality of SARS-CoV-2 antibody responses.

Design, Setting, and Participants

This cross-sectional study used 31 426 SARS-CoV-2 antibody test results from pediatric and adult patients. Data were collected from a New York City hospital from April 9 to August 31, 2020. The semiquantitative immunoglobin (Ig) G levels were compared between 85 pediatric and 3648 adult patients. Further analysis of SARS-CoV-2 antibody profiles was performed on sera from 126 patients aged 1 to 24 years.

Main Outcomes and Measures

SARS-CoV-2 antibody positivity rates and IgG levels were evaluated in patients from a wide range of age groups (1-102 years). SARS-CoV-2 IgG level, total antibody (TAb) level, surrogate neutralizing antibody (SNAb) activity, and antibody binding avidity were compared between children (aged 1-10 years), adolescents (aged 11-18 years), and young adults (aged 19-24 years).

Results

Among 31 426 antibody test results (19 797 [63.0%] female patients), with 1194 pediatric patients (mean [SD] age, 11.0 [5.3] years) and 30 232 adult patients (mean [SD] age, 49.2 [17.1] years), the seroprevalence in the pediatric (197 [16.5%; 95% CI, 14.4%-18.7%]) and adult (5630 [18.6%; 95% CI, 18.2%-19.1%]) patient populations was similar. The SARS-CoV-2 IgG level showed a negative correlation with age in the pediatric population (r = -0.45, P < .001) and a moderate but positive correlation with age in adults (r = 0.24, P < .001). Patients aged 19 to 30 years exhibited the lowest IgG levels (eg, aged 25-30 years vs 1-10 years: 99 [44-180] relative fluorescence units [RFU] vs 443 [188-851] RFU). In the subset cohort aged 1 to 24 years, IgG, TAb, SNAb and avidity were negatively correlated with age (eg, IgG: r = -0.51; P < .001). Children exhibited higher median (IQR) IgG levels, TAb levels, and SNAb activity compared with adolescents (eg, IgG levels: 473 [233-656] RFU vs 191 [82-349] RFU; P < .001) and young adults (eg, IgG levels: 473 [233-656] RFU vs 85 [38-150] RFU; P < .001). Adolescents also exhibited higher median (IQR) TAb levels, IgG levels, and SNAb activity than young adults (eg, TAb levels: 961 [290-2074] RFU vs 370 [125-697]; P = .006). In addition, children had higher antibody binding avidity compared with young adults, but the difference was not significant.

Conclusions and Relevance

The results of this study suggest that SARS-CoV-2 viral specific antibody response profiles are distinct in different age groups. Age-targeted strategies for disease screening and management as well as vaccine development may be warranted.

Clinical analysis of seven pediatric patients with coronavirus disease 2019 (COVID-19) in Jingzhou, Hubei, China: a retrospective study

BACKGROUND

The novel coronavirus disease 2019 (COVID-19) epidemic has spread globally, along with its incidence among children. The purpose of this study was to evaluate the clinical characteristics and outcomes of children infected with COVID-19 and to provide a reference for clinical work.

METHODS

The study retrospectively reviewed the clinical characteristics and prognosis of 7 children diagnosed with COVID-19 infection at The First People's Hospital of Jingzhou between January 30 and February 29, 2020.

RESULTS

Of the 7 cases, 2 were male and 5 were female, aged 3 months and 14 days to 12 years old (median age 3 years old). There was 1 asymptomatic carrier, 5 cases with mild type infection, which had the main symptoms of cough (4/5) and fever (4/5), and 1 case of moderate type. Among the 7 cases, serum white blood cell count was increased in 1 case, decreased in 1 case, liver transaminase was increased in 1 case, lactate dehydrogenase was increased in 3 cases, creatine kinase MB (CK-MB) was increased in 2 cases, and C-reactive protein was elevated in 2 cases. A total of 4 cases were complicated with mycoplasma pneumoniae and/or influenza B virus infection. A single case of chest computed tomography (CT) showed viral pneumonia. With routine antiviral and symptomatic support therapy, the median time taken for the results of nucleic acid testing by pharyngeal swab to become negative was 14 days (6-26 days) and the median hospital stay was 15 days (8-31 days). All participants were cured and subsequently discharged from hospital. Only 1 case was positive for nucleic acid testing by pharyngeal swab 1 month after being discharged, and the anal swab of 1 case for nucleic acid testing was positive 2 months after being discharged.

CONCLUSIONS

All children with COVID-19 who were included in this study in Jingzhou were infected via family clustering, and the laboratory examinations were not specific. Fever and cough were common symptoms, but all cases were mild and had good prognoses.

Cutaneous manifestations of COVID-19 in children (and adults): A virus that does not discriminate

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a beta coronavirus with a characteristic S-glycoprotein spike on the cell surface. Initial reports did not include cutaneous manifestations as a feature of COVID-19; however, there is a growing repertoire of reports demonstrating an array of dermatologic manifestations on the skin in children and adults. Dermatologic afflictions have been summarized into different categories several times, with the most recent analysis identifying six clinical patterns: urticaria, maculopapular-morbilliform eruption, papulovesicular exanthem, chilblain-like acral pattern, livedo reticularis-livedo racemosa pattern, and purpuric vasculitic pattern. In children, the dermatologic features appear to occur before or concomitantly with other COVID-19 manifestations. Dermatologists play a key role in diagnosing patients with COVID-19 who may present for the first time unwittingly exhibiting early signs of COVID-19. We have reviewed the current evidence on the dermatologic impact of COVID-19 in both the adult and pediatric populations.

Sex- and age-specific clinical and immunological features of coronavirus disease 2019

To simultaneously determine clinical and immunological responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in young and old females and males, 681 coronavirus disease 2019 (COVID-19) patients and 369 normal controls (NCs) were analyzed based on age and sex classifications using multiple linear regression analysis. Compared to the age-matched NCs, both young and old male and female non-comorbid COVID-19 patients had lower lymphocyte counts and alanine aminotransferase (ALT) concentration, and only young male and female patients had lower neutrophil counts. Compared to young patients, both old males and females had significantly higher plasma ALT and AST concentrations. Compared to young and old females, age-matched males had higher plasma ALT and AST concentrations, but only young males had higher C-reactive protein (CRP) concentration. Compared to females, old males, but not young males, showed higher incidence of critical illness. Compared to young patients, old females had more leukocyte and neutrophil counts above the normal upper limit and B cell count below the normal lower limit (NLL), while old males had more lymphocyte and natural killer (NK) cell counts below the NLL. No sex or age associations with B cell and NK cell counts were observed. However, there were age-dependent decreases in CD8+ T-cell counts in both male and female COVID-19 patients. Age was negatively associated with CD8+ T cell counts but positively associated with neutrophil count, CRP, ALT, and AST concentrations, and sex (females) was negatively associated with neutrophil count, CRP, ALT, and AST concentrations. The present study suggests that SARS-CoV-2 infection mainly induced 1) beneficial sex (female)-related differences regarding reduced COVID-19 disease severity and negative associations with inflammatory responses and liver damage, and 2) harmful age-related differences relating to negative associations with CD8+ T cell count and positive associations with inflammatory responses and liver damage. Thus, sex and age are biological variables that should be considered in the prevention and treatment of COVID-19.

COVID-19: Current knowledge in clinical features, immunological responses, and vaccine development

The COVID-19 pandemic has unfolded to be the most challenging global health crisis in a century. In 11 months since its first emergence, according to WHO, the causative infectious agent SARS-CoV-2 has infected more than 100 million people and claimed more than 2.15 million lives worldwide. Moreover, the world has raced to understand the virus and natural immunity and to develop vaccines. Thus, within a short 11 months a number of highly promising COVID-19 vaccines were developed at an unprecedented speed and are now being deployed via emergency use authorization for immunization. Although a considerable number of review contributions are being published, all of them attempt to capture only a specific aspect of COVID-19 or its therapeutic approaches based on ever-expanding information. Here, we provide a comprehensive overview to conceptually thread together the latest information on global epidemiology and mitigation strategies, clinical features, viral pathogenesis and immune responses, and the current state of vaccine development.

Prevalence and Longevity of SARS-CoV-2 Antibodies Among Health Care Workers

BACKGROUND

Understanding severe acute respiratory syndrome coronavirus 2 antibody prevalence in a spectrum of health care workers (HCWs) may provide benchmarks of susceptibility, help us understand risk stratification, and support enactment of better health policies and procedures.

METHODS

Blood serum was sampled at enrollment and 8-week follow-up from HCWs (n = 3458) and from community first responders (n = 226) for immunoglobulin G (IgG) analyses. Demographics, job duties, location, and coronavirus disease 2019-related information were collected.

RESULTS

The observed IgG antibody prevalence was 0.93% and 2.58% at enrollment (May/June) and 8-week follow-up (July/August), respectively, for HCWs, and 5.31% and 4.35% for first responders. For HCWs, significant differences (P < .05) between negative and positive at initial assessment were found for age, race, fever, and loss of smell, and at 8-week follow-up for age, race, and all symptoms. Antibody positivity persisted at least 8 weeks in all positive HCWs.

CONCLUSIONS

We found considerably lower antibody prevalence among HCWs compared with other published studies. While rigorous safety process measures instituted in our workplace and heightened awareness at and outside of the workplace among our HCWs may have contributed to our findings, the significant discrepancy from our community prevalence warrants further studies on other contributing factors.

COVID-19 in the paediatric population of Kazakhstan

Background: To date, there have been no studies of COVID-19 infection in children in Central Asia, particularly the Republic of Kazakhstan. This report analyses the epidemiological data on COVID-19 infection in children in Kazakhstan.Methods: The study included 650 paediatric patients diagnosed with COVID-19. Demographic and epidemiological data and the symptoms and radiological evidence of complications were collected and analysed. Children were sub-divided into four groups: neonates/infants, young children, older children and adolescents.Results: All of the 650 children were under 19 years of age, 56.3% of whom were male, and 122 (18.8%) were newborns and infants. The majority of cases (n = 558, 85.8%) were asymptomatic and only four cases were severe (0.6%). The symptoms were as follows in descending order: cough (14.8%), sore throat (12.8%), fever (9.1%) and rhinorrhoea (5.5%). Diarrhoea (2%), dyspnoea (1.8%) and muscle pain were rare (1.1%). Only three children required intensive care, including invasive ventilation. One patient had acute respiratory distress syndrome. There were no deaths.Conclusion: Most cases of COVID-19 infection in children in Kazakhstan were asymptomatic or the symptoms were mild. Only three patients required intensive care.

The younger the milder clinical course of COVID-19: Even in newborns?

BACKGROUND

Milder symptoms were observed in children with COVID-19. However, whether this also holds true for neonates is not known.

METHODS

The clinical data of a total of 3213 patients aged 2 years or below, including 749 neonates, in Brazil nationwide were studied. Comparisons were made between neonate and infant patients by conducting statistical tests.

RESULTS

Neonates appeared to bear more severe clinical courses. In addition to higher case fatality rates, newborns with COVID-19 had much shorter time from symptom onset to death and longer time from symptom onset to discharge. Dyspnoea, sore throat and cough were more prominent in neonate patients, suggestive of both upper and lower respiratory tract infection, as opposed to upper respiratory tract symptoms mostly observed in children.

CONCLUSION

Findings suggested that trained immunity provides a possible explanation because the innate immune system in newborns is not "well-trained" while that in adult tends to hyperactive.