Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Viral Load in the Upper Respiratory Tract of Children and Adults With Early Acute Coronavirus Disease 2019 (COVID-19).

The factors that contribute to transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by children are unclear. We analyzed viral load at the time of diagnosis in 53 children and 352 adults with coronavirus disease 2019 (COVID-19) in the first 5 days post symptom onset. No significant differences in SARS-CoV-2 RNA loads were seen between children and adults.

Viral co-infections among SARS-CoV-2-infected children and infected adult household contacts.

We evaluated the rates of viral respiratory co-infections among SARS-CoV-2-infected children. Twelve percent of SARS-CoV-2-infected children had viral co-infection with one or more common respiratory viruses. This was significantly more frequent than among their SARS-CoV-2-infected adult household contacts (0%; p=0.028). Compared to the same period the previous year, common respiratory viruses were less frequently detected (12% vs 73%, p<0.001).Conclusion: Despite partial lockdown with school and daycare closure, and consequently similar exposure to common viruses between children and adults, SARS-CoV-2-infected children had more frequent viral respiratory co-infections than their SARS-CoV-2-infected adult household contacts. Circulation of common respiratory viruses was less frequent during the SARS-CoV-2 outbreak when compared to the same period last year, showing the impact of partial lockdown on the circulation of common viruses. What is Known: • Viral respiratory co-infections are frequent in children. • SARS-CoV-2 can be identified alongside other respiratory viruses, but data comparing children and adults are lacking. What is New: • Children infected with SARS-CoV-2 are more likely to have viral respiratory co-infections than their SARS-CoV-2-infected adult household contacts, which is surprising in the context of partial lockdown with schools and daycare closed. • When compared to data collected during the same period last year, our study also showed that partial lockdown reduced circulation of common respiratory viruses.

[Treatment of SARS-CoV-2 in paediatrics : what is the evidence to date?] / Traitement du SARS-CoV-2 en pédiatrie : quelles évidences et quelle utilité ?

Although SARS-CoV-2 infects individuals of all ages, children show less severe symptoms. Nevertheless, the very rare COVID-19 severe cases in paediatrics require our full attention. Much research has been conducted and is still ongoing on effective treatments. On the antiviral front, no molecule has been proven effective yet and the results of several studies on the benefit of monoclonal antibodies and convalescent plasma are pending. On the side of immunomodulators, the benefit of steroids has been demonstrated for patients severely ill. Other molecules are being investigated. However, all these studies focused on adults and paediatric data are warranted.

Bien que le SARS-CoV-2 infecte des individus de tout âge, les enfants montrent des symptômes moins sévères. Les cas de Covid-19 graves sont exceptionnels en pédiatrie mais nécessitent néanmoins toute notre attention. De nombreuses études ont été menées et sont encore en cours à la recherche de traitements efficaces. Sur le plan antiviral, aucune molécule n'a fait ses preuves à l'heure actuelle. Les résultats de plusieurs travaux sur le bénéfice des anticorps monoclonaux et du plasma convalescent sont attendus avec impatience. Du côté des immunomodulateurs, le bénéfice des stéroïdes a pu être démontré chez les patients présentant une infection pulmonaire sévère. D'autres molécules sont à l'étude. Cependant, toutes ces études s'intéressent aux adultes et les données pédiatriques sont quasiment inexistantes.

Boosting Teenagers With Acellular Pertussis Vaccines Containing Recombinant or Chemically Inactivated Pertussis Toxin: A Randomized Clinical Trial.

BACKGROUND: Protection induced by acellular pertussis (aP) vaccines is partial and short-lived, especially in teenagers, calling for novel immunization strategies. METHODS: We conducted an investigator-driven proof-of-concept randomized controlled trial in aP-primed adolescents in Geneva to assess the immunogenicity and reactogenicity of a novel recombinant aP (r-aP) vaccine including recombinant pertussis toxin (PT) and filamentous hemagglutinin (FHA) coadministered with tetanus-diphtheria toxoids (Td), compared to a licensed tetanus-diphtheria-aP vaccine containing chemically detoxified PT (cd/Tdap). The primary immunological endpoints were day 28/365 geometric mean concentrations (GMCs) of total and neutralizing anti-PT antibodies. Memory B cells were assessed. RESULTS: Sixty-two aP-primed adolescents were randomized and vaccinated with r-aP + Td or cd/Tdap. Reactogenicity, adverse events, and baseline GMCs were similar between the groups. Day 28 PT-neutralizing GMCs were low after cd/Tdap (73.91 [95% confidence interval {CI}, 49.88-109.52] IU/mL) and approximately 2-fold higher after r-aP + Td (127.68 [95% CI, 96.73-168.53] IU/mL; P = .0162). Anti-PT GMCs were also low after cd/Tdap (52.43 [95% CI, 36.41-75.50] IU/mL) and 2-fold higher after r-aP + Td (113.74 [95% CI, 88.31-146.50] IU/mL; P = .0006). Day 28 anti-FHA GMCs were similar in both groups. Day 365 anti-PT (but not PT-neutralizing) GMCs remained higher in r-aP + Td vaccinees. PT-specific memory B cells increased significantly after r-aP + Td but not cd/Tdap boosting. CONCLUSIONS: Boosting aP-primed adolescents with r-aP induced higher anti-PT and PT-neutralizing responses than cd/Tdap and increased PT-specific memory B cells. Despite this superior immunogenicity, r-aP may have to be given repeatedly, earlier, and/or with novel adjuvants to exert an optimal influence in aP-primed subjects. CLINICAL TRIALS REGISTRATION: NCT02946190.

[Persistant fevers of infectious origin in children]. / Fièvres prolongées d'origine infectieuse chez l'enfant.

Prolonged fevers in children are a regular challenge for the paediatrician or any physician caring for these children (emergency physicians, pediatric infectious diseases specialists). The causes are multiple, classified into three major families : infectious, inflammatory and oncological. Infectious causes are the most common and account for more than 50 % of cases. The objective of this review is to guide physicians in charge of these patients throughout their management by focusing on the quest of infectious causes.

Les fièvres prolongées chez l'enfant sont un défi régulier pour le pédiatre traitant ou toute personne accueillant en consultation ces enfants (médecins des urgences, infectiologues pédiatres). Les étiologies de ces fièvres sont multiples et peuvent être classées en trois grandes familles : infectieuse, inflammatoire/auto-immune et oncologique. Les étiologies infectieuses sont les plus courantes et représentent plus de 50 % des cas. L'objectif de cet article est de guider les médecins de ces patients tout au long de leur prise en charge en axant sur la recherche des étiologies infectieuses.

Swiss Evaluation Registry for Pediatric Infective Endocarditis (SERPIE) - Risk factors for complications in children and adolescents with infective endocarditis.

BACKGROUND: Infective endocarditis (IE) in pediatric patients is a severe cardiac disease and its actual epidemiology and clinical outcome in Switzerland is scarcely studied. METHODS: Retrospective nationwide multicenter data analysis of pediatric IE in children (<18 years) between 2011 and 2020. RESULTS: 69 patients were treated for definite (40/69;58%) or possible IE (29/69;42%). 61% (42/69) were male. Diagnosis was made at median 6.4 years (IQR 0.8-12.6) of age with 19 patients (28%) during the first year of life. 84% (58/69) had congenital heart defects. IE was located on pulmonary (25/69;35%), mitral (10/69;14%), tricuspid (8/69;12%) and aortic valve (6/69;9%), and rarely on ventricular septal defect (VSD;4/69;6%) and atrial septal defect (ASD;1/69;1%). In 22% (16/69) localization was unknown. 70% (48/69) had postoperative IE, with prosthetic material involved in 60% (29/48; right ventricular to pulmonary artery conduit (24), VSD (4), ASD (1)). Causative organisms were mostly Staphylococci spp. (25;36%) including Staphylococcus aureus (19;28%), and Streptococci spp. (13;19%). 51% (35/69) suffered from severe complications including congestive heart failure (16;23%), sepsis (17;25%) and embolism (19;28%). Staphylococcus aureus was found as a predictor of severe complications in univariate and multivariate analysis (p = 0.02 and p = 0.033). In 46% (32/69) cardiac surgery was performed. 7% (5/69) died. CONCLUSIONS: IE in childhood remains a severe cardiac disease with relevant mortality. The high morbidity and high rate of complications is associated with Staphylococcus aureus infections. Congenital heart defects act as a risk factor for IE, in particular the high number of cases associated with prosthetic pulmonary valve needs further evaluation and therapeutic alternatives.

Endothelial glycocalyx degradation in multisystem inflammatory syndrome in children related to COVID-19.

Multisystem inflammatory syndrome in children (MIS-C) represents a rare but severe complication of severe acute respiratory syndrome coronavirus 2 infection affecting children that can lead to myocardial injury and shock. Vascular endothelial dysfunction has been suggested to be a common complicating factor in patients with coronavirus disease 2019 (COVID-19). This study aims to characterize endothelial glycocalyx degradation in children admitted with MIS-C. We collected blood and urine samples and measured proinflammatory cytokines, myocardial injury markers, and endothelial glycocalyx markers in 17 children admitted with MIS-C, ten of which presented with inflammatory shock requiring intensive care admission and hemodynamic support with vasopressors. All MIS-C patients presented signs of glycocalyx deterioration with elevated levels of syndecan-1 in blood and both heparan sulfate and chondroitin sulfate in the urine. The degree of glycocalyx shedding correlated with tumor necrosis factor-α concentration. Five healthy age-matched children served as controls. Patients with MIS-C presented severe alteration of the endothelial glycocalyx that was associated with disease severity. Future studies should clarify if glycocalyx biomarkers could effectively be predictive indicators for the development of complications in adult patients with severe COVID-19 and children with MIS-C. KEY MESSAGES : Children admitted with MIS-C presented signs of endothelial glycocalyx injury with elevated syndecan-1 and heparan sulfate level. Syndecan-1 levels were associated with MIS-C severity and correlated TNF-α concentration. Syndecan-1 and heparan sulfate may represent potential biomarkers for patients with severe COVID-19 or MIS-C.

Immunological Assessment of Pediatric Multisystem Inflammatory Syndrome Related to Coronavirus Disease 2019.

BACKGROUND: Recently, cases of multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19) have been reported worldwide. Negative polymerase chain reaction (RT-PCR) testing associated with positive serology in most of the cases suggests a postinfectious syndrome. Because the pathophysiology of this syndrome is still poorly understood, extensive virological and immunological investigations are needed. METHODS: We report a series of 4 pediatric patients admitted to Geneva University Hospitals with persistent fever and laboratory evidence of inflammation meeting the published definition of MIS-C related to COVID-19, to whom an extensive virological and immunological workup was performed. RESULTS: RT-PCRs on multiple anatomical compartments were negative, whereas anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin A (IgA) and immunoglobulin G (IgG) were strongly positive by enzyme-linked immunosorbent assay and immunofluorescence. Both pseudoneutralization and full virus neutralization assays showed the presence of neutralizing antibodies in all children, confirming a recent infection with SARS-CoV-2. The analyses of cytokine profiles revealed an elevation in all cytokines, as reported in adults with severe COVID-19. Although differing in clinical presentation, some features of MIS-C show phenotypic overlap with hemophagocytic lymphohistiocytosis (HLH). In contrast to patients with primary HLH, our patients showed normal perforin expression and natural killer (NK) cell degranulation. The levels of soluble interleukin (IL)-2 receptor (sIL-2R) correlated with the severity of disease, reflecting recent T-cell activation. CONCLUSION: Our findings suggest that MIS-C related to COVID-19 is caused by a postinfectious inflammatory syndrome associated with an elevation in all cytokines, and markers of recent T-cell activation (sIL-2R) occurring despite a strong and specific humoral response to SARS-CoV-2. Further functional and genetic analyses are essential to better understand the mechanisms of host-pathogen interactions.