Acute symptoms in SARS-CoV-2 positive adolescents aged 15-18 years - Results from a Danish national cross-sectional survey study

The Effect of Age and Comorbidities: Children vs. Adults in Their Response to SARS-CoV-2 Infection

While children have experienced less severe coronavirus disease (COVID-19) after SARS-CoV-2 infection than adults, the cause of this remains unclear. The objective of this study was to describe the humoral immune response to COVID-19 in child vs. adult household contacts, and to identify predictors of the response over time. In this prospective cohort study, children with a positive SARS-CoV-2 polymerase chain reaction (PCR) test (index case) were recruited along with their adult household contacts. Serum IgG antibodies against SARS-CoV-2 S1/S2 spike proteins were compared between children and adults at 6 and 12 months after infection. A total of 91 participants (37 adults and 54 children) from 36 families were enrolled. Overall, 78 (85.7%) participants were seropositive for anti-S1/S2 IgG antibody at 6 months following infection; this was higher in children than in adults (92.6% vs. 75.7%) (p = 0.05). Significant predictors of a lack of SARS-CoV-2 seropositivity were age ≥ 25 vs. < 12 years (odds ratio [OR] = 0.23, p = 0.04), presence of comorbidities (vs. none, adjusted OR = 0.23, p = 0.03), and immunosuppression (vs. immunocompetent, adjusted OR = 0.17, p = 0.02).

Characterization of young and aged ferrets as animal models for SARS-CoV-2 infection with focus on neutrophil extracellular traps

Neutrophil extracellular traps (NETs) are net-like structures released by activated neutrophils upon infection [e.g., severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)] as part of the innate immune response that have protective effects by pathogen entrapment and immobilization or result in detrimental consequences for the host due to the massive release of NETs and their impaired degradation by nucleases like DNase-1. Higher amounts of NETs are associated with coronavirus disease 2019 (COVID-19) severity and are a risk factor for severe disease outcome. The objective of our study was to investigate NET formation in young versus aged ferrets to evaluate their value as translational model for SARS-CoV-2-infection and to correlate different NET markers and virological parameters. In each of the two groups (young and aged), nine female ferrets were intratracheally infected with 1 mL of 106 TCID50/mL SARS-CoV-2 (BavPat1/2020) and euthanized at 4, 7, or 21 days post-infection. Three animals per group served as negative controls. Significantly more infectious virus and viral RNA was found in the upper respiratory tract of aged ferrets. Interestingly, cell-free DNA and DNase-1 activity was generally higher in bronchoalveolar lavage fluid (BALF) but significantly lower in serum of aged compared to young ferrets. In accordance with these data, immunofluorescence microscopy revealed significantly more NETs in lungs of aged compared to young infected ferrets. The association of SARS-CoV-2-antigen in the respiratory mucosa and NET markers in the nasal conchae, but the absence of virus antigen in the lungs, confirms the nasal epithelium as the major location for virus replication as described for young ferrets. Furthermore, a strong positive correlation was found between virus shedding and cell-free DNA or the level of DNAse-1 activity in aged ferrets. Despite the increased NET formation in infected lungs of aged ferrets, the animals did not show a strong NET phenotype and correlation among tested NET markers. Therefore, ferrets are of limited use to study SARS-CoV-2 pathogenesis associated with NET formation. Nevertheless, the mild to moderate clinical signs, virus shedding pattern, and the lung pathology of aged ferrets confirm those animals as a relevant model to study age-dependent COVID-19 pathogenesis.

Clinical features of COVID-19 in Italian outpatient children and adolescents during Parental, Delta, and Omicron waves: a prospective, observational, cohort study

Introduction

COVID-19 features changed with the Omicron variant of SARS-CoV-2 in adults. This study aims to describe COVID-19 symptoms in children and adolescents during the Parental, Delta, and Omicron eras.

Methods

A single-centre, prospective observational study was conducted on individuals aged 0-20 years attending the University Hospital of Padua (Italy) from April 2020 to December 2022. COVID-19 cases were defined by positive SARS-CoV-2 molecular detection and/or serology; patient/family symptoms and virological positivity were considered to determine the infection onset. Variables were summarized and compared using appropriate tests of descriptive statistics.

Results

A total of 509 cases [46% female, median age eight years (IQR: 4-12)] were studied. Three-hundred-eighty-seven (76%), 52 (10%), and 70 (14%) subjects experienced COVID-19 during the Parental, Delta, and Omicron waves, respectively. All subjects developed an asymptomatic/mild COVID-19. Overall, the most frequent symptoms were fever (47%) and rhinitis (21%), which showed a significant increasing incidence from the Parental to Omicron waves (p < 0.001). Conversely, diarrhea was most common during the pre-Omicron eras (p = 0.03). Stratifying symptoms according to the age group, fever, rhinitis, and skin rashes were observed more frequently among infants/toddlers; conversely, fatigue was more common in children older than five years. The duration of symptoms was similar across different SARS-CoV-2 variants of concern (VOCs); conversely, the number of symptoms varied according to the age group (p < 0.0001).

Discussion

This study showed differences in COVID-19 clinical presentation among infants, children, and adolescents and confirmed Omicron infection is more likely to be associated with upper respiratory symptoms. However, further population-based studies are needed to support these findings. In addition, active surveillance will play a crucial role in assessing the disease severity of future VOCs.

Risk of body weight changes among Danish children and adolescents during the COVID-19 pandemic

BACKGROUND

Knowledge of COVID-19 and the pandemic's effects on Danish children's body weight is limited.

OBJECTIVE

Objectives were to investigate (I) risk of weight changes among Danish children with and without SARS-CoV-2, (II) associations between weight changes, psychological symptoms, and long COVID symptoms, and (III) weight distribution pre- and post-pandemic.

METHODS

A national survey was administered to all Danish children aged 0-18 years, with prior COVID-19 (cases) and matched references including questions on weight, weight changes during the pandemic and long COVID-related symptoms. Descriptive statistics and logistic regression were used. Weight distribution was compared with a pre-pandemic database.

RESULTS

In all, 17 627 cases and 54 656 references were included. The 4-18-year-old cases had lower odds of unintended weight gain. The 2-3-year-old cases had higher odds and the 15-18-year-old cases lower odds of weight loss compared to references. Regardless of COVID-19 status, any reported long COVID-related symptom was associated with a change in body weight. No sign of increasing obesity rates was found among Danish children post-pandemic.

CONCLUSION

COVID-19 was associated with higher odds of weight loss in 2-3-year-olds and lower odds of unintended weight gain in 4-18-year-olds. Any long COVID-related symptom was associated with higher odds of weight changes regardless of COVID-19 status.

Natural course of health and well-being in non-hospitalised children and young people after testing for SARS-CoV-2: a prospective follow-up study over 12 months

Background

Despite high numbers of children and young people (CYP) having acute COVID, there has been no prospective follow-up of CYP to establish the pattern of health and well-being over a year following infection.

Methods

A non-hospitalised, national sample of 5086 (2909 SARS-COV-2 Positive; 2177 SARS-COV-2 Negative at baseline) CYP aged 11-17 completed questionnaires 6- and 12-months after PCR-tests between October 2020 and March 2021 confirming SARS-CoV-2 infection (excluding CYP with subsequent (re)infections). SARS-COV-2 Positive CYP was compared to age, sex and geographically-matched test-negative CYP.

Findings

Ten of 21 symptoms had a prevalence less than 10% at baseline, 6- and 12-months post-test in both test-positives and test-negatives. Of the other 11 symptoms, in test-positives who had these at baseline, the prevalence of all symptoms declined greatly by 12-months. For CYP first describing one of these at 6-months, there was a decline in prevalence by 12-months. The overall prevalence of 9 of 11 symptoms declined by 12-months. As many CYP first described shortness of breath and tiredness at either 6- or 12-months, the overall prevalence of these two symptoms in test-positives appeared to increase by 6-months and increase further by 12-months. However, within-individual examination demonstrated that the prevalence of shortness of breath and tiredness actually declined in those first describing these two symptoms at either baseline or 6-months. This pattern was also evident for these two symptoms in test-negatives. Similar patterns were observed for validated measures of poor quality of life, emotional and behavioural difficulties, poor well-being and fatigue. Moreover, broadly similar patterns and results were noted for the sub-sample (N = 1808) that had data at baseline, 3-, 6- and 12-months post-test.

Interpretation

In CYP, the prevalence of adverse symptoms reported at the time of a positive PCR-test declined over 12-months. Some test-positives and test-negatives reported adverse symptoms for the first time at six- and 12-months post-test, particularly tiredness, shortness of breath, poor quality of life, poor well-being and fatigue suggesting they are likely to be caused by multiple factors.

Funding

NIHR/UKRI (ref: COVLT0022).

The Challenge of Long COVID-19 Management: From Disease Molecular Hallmarks to the Proposal of Exercise as Therapy

Long coronavirus disease 19 (COVID-19) is the designation given to a novel syndrome that develops within a few months after infection by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and that is presenting with increasing incidence because of the numerous cases of infection. Long COVID-19 is characterized by a sequela of clinical symptoms that concern different organs and tissues, from nervous, respiratory, gastrointestinal, and renal systems to skeletal muscle and cardiovascular apparatus. The main common molecular cause for all long COVID-19 facets appears to be related to immune dysregulations, the persistence of inflammatory status, epigenetic modifications, and alterations of neurotrophin release. The prevention and management of long COVID-19 are still inappropriate because many aspects need further clarification. Exercise is known to exert a deep action on molecular dysfunctions elicited by long COVID-19 depending on training intensity, duration, and continuity. Evidence suggests that it could improve the quality of life of long COVID-19 patients. This review explores the main clinical features and the known molecular mechanisms underlying long COVID-19 in the perspective of considering exercise as a co-medication in long COVID-19 management.