Comparison between the Viral Illness Caused by SARS-CoV-2, Influenza Virus, Respiratory Syncytial Virus and Other Respiratory Viruses in Pediatrics.

Respiratory tract infections (RTIs) are the most common infectious syndromes, primarily caused by viruses. The primary objective was to compare the illness courses between historical RTIs and recent SARS-CoV-2 infections. The study cohort consisted of RTI cases evaluated at the Pediatric Emergency Departments of Padua and Bologna, discharged or admitted with microbiologically confirmed viral RTI between 1 November 2018 and 30 April 2019 (historical period) and 1 March 2020 and 30 April 2021 (recent period). We evaluated the risk of oxygen or respiratory support, hospitalization, antibiotic therapy, and complications among different viral infections. The odds ratio (OR) and the 95% confidence intervals (CIs) were estimated through mixed-effect logistic regression models, including a random intercept on the individual and hospital. We identified 767 RTIs: 359 in the historical period compared with 408 SARS-CoV-2 infections. Infections of SARS-CoV-2 had a lower risk of being admitted (OR 0.04, 95% CI 0.03-0.07), receiving respiratory support (OR 0.19, 95% CI 0.06-0.58), needing antibiotic therapy (OR 0.35, 95% CI 0.22-0.56) and developing complications (OR 0.27, 95% CI 0.14-0.51) compared to all other viral RTIs. COVID-19 in children is clinically similar to other viral RTIs but is associated with a less severe infection course. Thus, most prevention strategies implemented for SARS-CoV-2 should still be considered during RSV and Influenza epidemics.

Risk of SARS-CoV-2 Reinfection in Children Within the 12 Months Following Mild COVID-19: Insights From a Survey Study.

Understanding the correlation between immune response and protection from COVID-19 will play a pivotal role in predicting the effectiveness of vaccines in children. We studied SARS-CoV-2 reinfection risk in children 12 months post-mild COVID-19. Children under 5 years old exhibited lower reinfection risk than older infected or vaccinated siblings during 12 months postimmunization.

Stronger and durable SARS-CoV-2 immune response to mRNA vaccines in 5-11 years old children with prior COVID-19.

BACKGROUND AND OBJECTIVES: mRNA vaccines elicit a durable humoral response to SARS-CoV-2 in adults, whereas evidence in children is scarce. This study aimed to assess the early and long-term immune response to the mRNA vaccine in children with or without previous SARS-CoV-2 infection. METHODS: In a multicentre prospective observational study, we profiled the immune response to the Pfizer BioNTech (BNT162b2) vaccine in 5-11-year-old children attending the University Pediatric Hospital of Padua and Bambino-Gesù Hospital in Rome (Italy) from December-2021 to February-2023. Blood samples were collected pre-, 1-, and 6-months after vaccination. Neutralizing antibodies (NAbs) and anti-spike-receptor-binding-domain (anti-S-RBD) IgG titers were analyzed through Plaque Reduction Neutralization Test (PRNT) and chemiluminescent immune-enzymatic assay (CLIA), respectively. Immune cell phenotypes were analyzed by flow cytometry. RESULTS: Sixty children (26 [43 %] female, median age = 8 years [IQR = 7-10.7]) were enrolled in the study, including 46 children with a laboratory-confirmed previous COVID-19 (SARS-CoV-2-recovered) and 14 SARS-CoV-2-naïve participants defined as the absence of antigen-specific antibodies before vaccination. SARS-CoV-2-recovered participants recorded higher anti-S-RBD IgG and Wild-type and Omicron BA.2 NAbs titers than SARS-CoV-2-naïve participants at both 1- and 6-months after vaccination. Antibody titers correlated with T (Tregs) and B (Bregs) regulatory cell frequencies in SARS-CoV-2-recovered children. Both SARS-CoV-2-recovered and SARS-CoV-2-naïve participants decreased antibody titers by approximately 100 to 250 % from 1 to 6 months. While children with immunocompromising underlying conditions developed immune responses comparable to those of healthy children, solid organ transplant recipients exhibited lower levels of NAbs and anti-S-RBD IgG titers, as well as reduced frequencies of Tregs and Bregs. CONCLUSIONS: mRNA vaccination triggered a higher production of specific anti-SARS-CoV-2 antibodies along with increased levels of regulatory cells in children with previous SARS-CoV-2 infection up to the following 6 months. These findings provide insights into boosting pre-existing immunity.

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.

Retrospective Analysis of the Real-World Use of Topical Antimicrobials in the Paediatric Population with Impetigo in Italy: Focus on the Role of Ozenoxacin 1% Cream.

Using electronic data from a large population-based network of Family Paediatricians (Pedianet), we aimed to describe the use of topical antimicrobials, including ozenoxacin 1% cream, in impetigo in children in Italy. We included 2929 children aged 6 months-14 years from 2016 to 2019 with at least one episode of impetigo treated with topical antimicrobials. Overall, 3051 cases of impetigo were included in the analysis. Treatment started in most cases on the same day as the impetigo diagnosis and lasted around eight days. In about 8% of the cases, a systemic antibiotic was prescribed after the topical antimicrobial, usually after 4-14 days. In this study, ozenoxacin was used in 8% of the cases. Treatment duration was significantly shorter for patients prescribed ozenoxacin compared to the whole study population (median of six vs. seven days, respectively). In contrast, the rate of treatment failure was similar. Very few adverse reactions were identified.