Transmission of SARS-CoV-2 infection among children in summer schools applying stringent control measures in Barcelona, Spain

Deciphering the Longevity and Levels of SARS-CoV-2 Antibodies in Children: A Year-Long Study Highlighting Clinical Phenotypes and Age-Related Variations

BACKGROUND

Identifying potential factors correlated with the sustained presence of antibodies in plasma may facilitate improved retrospective diagnoses and aid in the appraisal of pertinent vaccination strategies for various demographic groups. The main objective was to describe the persistence of anti-spike IgG one year after diagnosis in children and analyse its levels in relation to epidemiological and clinical variables.

METHODS

A prospective, longitudinal, observational study was conducted in a university reference hospital in the Metropolitan Region of Barcelona (Spain) (March 2020-May 2021). This study included patients under 18 years of age with SARS-CoV-2 infection (positive PCR or antigen tests for SARS-CoV-2). Clinical and serological follow-up one year after infection was performed.

RESULTS

We included 102 patients with a median age of 8.8 years. Anti-spike IgG was positive in 98/102 (96%) 12 months after the infection. There were higher anti-spike IgG levels were noted in patients younger than 2 years (p = 0.034) and those with pneumonia (p < 0.001). A positive and significant correlation was observed between C-reactive protein at diagnosis and anti-spike IgG titre one-year after diagnosis (p = 0.027).

CONCLUSION

Anti-SARS-CoV-2 IgG antibodies were detected in almost all paediatric patients one year after infection. We also observed a positive correlation between virus-specific IgG antibody titres with SARS-CoV-2 clinical phenotype (pneumonia) and age (under 2 years old).

Secondary infections of COVID-19 in schools and the effectiveness of school-based interventions: a systematic review and meta-analysis

OBJECTIVES

This meta-analysis explored secondary infections of SARS-CoV-2 and the effectiveness of non-pharmaceutical interventions (NPIs) in school settings, with the aim of providing a reference to formulate scientific prevention and response strategies for similar major public health emergencies in specific settings.

STUDY DESIGN

This was a systematic review and meta-analysis.

METHODS

Systematic searches were conducted in PubMed, Web of Science and the Cochrane Library through to 1 August 2022 using the following key search terms: COVID-19, SARS-CoV-2, secondary attack rate, school, transmission, etc. The IVhet model was used for the meta-analysis, and the I2 index and Cochran's Q-test were used to assess heterogeneity. Publication bias was examined using Doi plot, Galbraith plots and Luis Furuya-Kanamori index. Prevalence Critical Appraisal Tool was used to assess the quality of the included articles, while Grading of Recommendations Assessment, Development, and Evaluation was used to rate the quality of the evidence. Subgroup analyses were conducted to explore the potential source of heterogeneity.

RESULTS

Thirty-four studies involving 226,727 school contacts and 2216 secondary cases were included in this study. The pooled secondary attack rates (SARs) of close contacts, staff contacts and student contacts were 0.67% (95% confidence interval [CI]: 0.11, 1.56), 0.79% (95% CI: 0.00, 6.72) and 0.50% (95% CI: 0.00, 4.48), respectively. Subgroup analysis suggested that multiple or specific combinations (e.g. the combination of contact restriction and hygiene action) of NPIs appeared to be associated with lower SARs.

CONCLUSIONS

The SAR of SARS-CoV-2 was low in schools. Multiple or specific combinations of prevention strategies appear to mitigate SARS-CoV-2 transmission in school settings. These findings provide a basis for continuous improvement of response strategies to major public health emergencies in the school environment.

Factors associated with the formation of SARS-CoV-2 case-clusters in Danish schools: a nationwide register-based observational study

A register-based retrospective observational study was conducted to describe SARS-CoV-2 cases and case-clusters in schoolchildren of Danish primary and lower secondary schools and identify which factors were associated with the occurrence of case-clusters in schools. The study period was the autumn school semester 2021. Clusters were defined as three or more cases in a school-class level within 14 days. Descriptive analysis was carried out and multivariable logistic regression analysis was performed to determine which factors were associated with case introductions (i.e., primary case) being linked to a cluster. More cases and clusters were identified in lower than in higher class levels. Out of 21,497 cases introduced into a school, 41.6% started a cluster. A higher assumed immunity level in a class level was significantly reducing the odds of a case introduction being linked to a cluster (e.g., assumed immunity of ≥80% vs <20%: OR: 0.28; 95%CI: 0.17-0.44). A previous infection (in the primary case) had a protective effect (OR: 0.58; 95%CI: 0.33-0.99). This study suggests that most cases appearing in schools did not induce clusters, but that once cluster occur sizes can be large. It further indicates that vaccination of children markedly reduces the risk of secondary infections.

SARS-CoV-2 infection prevention and control measures in Belgian schools between December 2020 and June 2021 and their association with seroprevalence: a cross-sectional analysis of a prospective cohort study

BACKGROUND

To protect school-aged children from the potential consequences of a new viral infection, public health authorities recommended to implement infection prevention and control (IPC) measures in school settings. Few studies evaluated the implementation of these measures and their effect on SARS-CoV-2 infection rates among pupils and staff. The aim of this study was to describe the implementation of infection prevention and control (IPC) measures in Belgian schools and assess its relation to the prevalence of anti-SARS-CoV-2 antibodies among pupils and staff.

METHODS

We conducted a prospective cohort study in a representative sample of primary and secondary schools in Belgium between December 2020 and June 2021. The implementation of IPC measures in schools was assessed using a questionnaire. Schools were classified according to their compliance with the implementation of IPC measures as 'poor', 'moderate' or 'thorough'. Saliva samples were collected from pupils and staff to determine the SARS-CoV-2 seroprevalence. To assess the association between the strength of implementation of IPC measures and SARS-CoV-2 seroprevalence among pupils and staff, we conducted a cross-sectional analysis using the data collected in December 2020/January 2021.

RESULTS

A variety of IPC measures (ventilation, hygiene and physical distancing) was implemented by more than 60% of schools, with most attention placed on hygiene measures. In January 2021, poor implementation of IPC measures was associated with an increase in anti-SARS-CoV-2 antibody prevalence among pupils from 8.6% (95%CI: 4.5 - 16.6) to 16.7% (95%CI: 10.2 - 27.4) and staff from 11.5% (95%CI: 8.1 - 16.4) to 17.6% (95%CI: 11.5 - 27.0). This association was only statistically significant for the assessment of all IPC measures together in the population comprised of pupils and staff.

CONCLUSIONS

Belgian schools were relatively compliant with recommended IPC measures at the school level. Higher SARS-CoV-2 seroprevalence among pupils and staff was found in schools with poor implementation of IPC measures, compared to schools with thorough implementation.

TRIAL REGISTRATION

This trial is registered under the NCT04613817 ClinicalTrials.gov Identifier on November 3, 2020.

COVID-19 in children: epidemic issues and candidate vaccines

ABSTRACT

A large-scale vaccination of coronavirus disease-19 (COVID-19) in adults has been conducted for nearly a year, and there is a growing recognition that immunization for children is also essential. It has been months since emergency use of pediatric COVID-19 vaccine was approved, we reviewed the prevalence and transmission of COVID-19 in children. The prevalence of COVID-19 in children is reduced due to vaccination even in a Delta prevalent period, so an increase in the vaccination rate is needed in children. Although the precise role of children in the transmission requires more research to uncover, they likely played a significant role, according to the available literature. We also described four candidate COVID-19 vaccines for children on their safety and immunogenicity and the impact of severe acute respiratory syndrome coronavirus 2 variants on childhood vaccination. Safety issues on pediatric vaccines post-approval, like adverse events following immunization and adverse events of special interest require studies on long-term and effective regulatory mechanisms.

SARS-CoV-2 Circulation in the School Setting: A Systematic Review and Meta-Analysis

The contribution of children to viral spread in schools is still debated. We conducted a systematic review and meta-analysis of studies to investigate SARS-CoV-2 transmission in the school setting. Literature searches on 15 May 2021 yielded a total of 1088 publications, including screening, contact tracing, and seroprevalence studies. MOOSE guidelines were followed, and data were analyzed using random-effects models. From screening studies involving more than 120,000 subjects, we estimated 0.31% (95% confidence interval (CI) 0.05–0.81) SARS-CoV-2 point prevalence in schools. Contact tracing studies, involving a total of 112,622 contacts of children and adults, showed that onward viral transmission was limited (2.54%, 95% CI 0.76–5.31). Young index cases were found to be 74% significantly less likely than adults to favor viral spread (odds ratio (OR) 0.26, 95% CI 0.11–0.63) and less susceptible to infection (OR 0.60; 95% CI 0.25–1.47). Lastly, from seroprevalence studies, with a total of 17,879 subjects involved, we estimated that children were 43% significantly less likely than adults to test positive for antibodies (OR 0.57, 95% CI 0.49–0.68). These findings may not applied to the Omicron phase, we further planned a randomized controlled trial to verify these results.

Child transmission of SARS-CoV-2: a systematic review and meta-analysis

BACKGROUND

Understanding of the role of children in COVID-19 transmission has significant implications for school and childcare policies, as well as appropriate targeting of vaccine campaigns. The objective of this systematic review was to identify the role of children in SARS-CoV-2 transmission to other children and adults.

METHODS

MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, and Web of Science were electronically searched for articles published before March 31, 2021. Studies of child-to-child and child-to-adult transmission and quantified the incidence of index and resulting secondary attack rates of children and adults in schools, households, and other congregate pediatric settings were identified. All articles describing confirmed transmission of SARS-CoV-2 from a child were included. PRISMA guidelines for data abstraction were followed, with each step conducted by two reviewers.

RESULTS

40 of 6110 articles identified met inclusion criteria. Overall, there were 0.8 secondary cases per primary index case, with a secondary attack rate of 8.4% among known contacts. The secondary attack rate was 26.4% among adult contacts versus 5.7% amongst child contacts. The pooled estimate of a contact of a pediatric index case being infected as secondary case was 0.10 (95% CI 0.03-0.25).

CONCLUSIONS

Children transmit COVID-19 at a lower rate to children than to adults. Household adults are at highest risk of transmission from an infected child, more so than adults or children in other settings.

Transmission of SARS-CoV-2 by children and young people in households and schools: A meta-analysis of population-based and contact-tracing studies

BACKGROUND

The role of children and young people (CYP) in transmission of SARS-CoV-2 in household and educational settings remains unclear. We undertook a systematic review and meta-analysis of contact-tracing and population-based studies at low risk of bias.

METHODS

We searched 4 electronic databases on 28 July 2021 for contact-tracing studies and population-based studies informative about transmission of SARS-CoV-2 from 0 to 19 year olds in household or educational settings. We excluded studies at high risk of bias, including from under-ascertainment of asymptomatic infections. We undertook multilevel random effects meta-analyses of secondary attack rates (SAR: contact-tracing studies) and school infection prevalence, and used meta-regression to examine the impact of community SARS-CoV-2 incidence on school infection prevalence.

FINDINGS

4529 abstracts were reviewed, resulting in 37 included studies (16 contact-tracing; 19 population studies; 2 mixed studies). The pooled relative transmissibility of CYP compared with adults was 0.92 (0.68, 1.26) in adjusted household studies. The pooled SAR from CYP was lower (p = 0.002) in school studies 0.7% (0.2, 2.7) than household studies (7.6% (3.6, 15.9) . There was no difference in SAR from CYP to child or adult contacts. School population studies showed some evidence of clustering in classes within schools. School infection prevalence was associated with contemporary community 14-day incidence (OR 1.003 (1.001, 1.004), p<0.001).

INTERPRETATION

We found no difference in transmission of SARS-CoV-2 from CYP compared with adults within household settings. SAR were markedly lower in school compared with household settings, suggesting that household transmission is more important than school transmission in this pandemic. School infection prevalence was associated with community infection incidence, supporting hypotheses that school infections broadly reflect community infections. These findings are important for guiding policy decisions on shielding, vaccination school and operations during the pandemic.

Multiplex Antibody Analysis of IgM, IgA and IgG to SARS-CoV-2 in Saliva and Serum From Infected Children and Their Close Contacts

COVID-19 affects children to a lesser extent than adults but they can still get infected and transmit SARS-CoV-2 to their contacts. Field deployable non-invasive sensitive diagnostic techniques are needed to evaluate the infectivity dynamics of SARS-CoV-2 in pediatric populations and guide public health interventions, particularly if this population is not fully vaccinated. We evaluated the utility of high-throughput Luminex assays to quantify saliva IgM, IgA and IgG antibodies against five SARS-CoV-2 spike (S) and nucleocapsid (N) antigens in a contacts and infectivity longitudinal study in 122 individuals (52 children and 70 adults). We compared saliva versus serum/plasma samples in infected children and adults diagnosed by weekly RT-PCR over 35 days (n=62), and those who consistently tested negative over the same follow up period (n=60), in the Summer of 2020 in Barcelona, Spain. Saliva antibody levels in SARS-CoV-2 RT-PCR positive individuals were significantly higher than in negative individuals and correlated with those measured in sera/plasmas. Asymptomatic infected individuals had higher levels of anti-S IgG than symptomatic individuals, suggesting a protective anti-disease role for antibodies. Higher anti-S IgG and IgM levels in serum/plasma and saliva, respectively, in infected children compared to infected adults could also be related to stronger clinical immunity in them. Among infected children, males had higher levels of saliva IgG to N and RBD than females. Despite overall correlation, individual clustering analysis suggested that responses that may not be detected in blood could be patent in saliva, and vice versa.

In conclusion, measurement of SARS-CoV-2-specific saliva antibodies should be considered as a complementary non-invasive assay to serum/plasma to determine COVID-19 prevalence and transmission in pediatric populations before and after vaccination campaigns.

Pediatric Hospitalizations after School Reopening during the SARS-CoV-2 Alpha (B.1.1.7) Variant Spread: A Multicenter Cross-sectional Study in Israel

This multicenter, cross-sectional study provides evidence on SARS-CoV-2-associated ED visits and hospitalizations in pediatric wards and intensive care units, after school reopening during the SARS-CoV-2 Alpha (B.1.1.7) variant spread in Israel. Study findings suggest that school reopening was not followed by an increase in SARS-CoV-2-related pediatric morbidity.

How Did the COVID-19 Lockdown Affect Children and Adolescent's Well-Being: Spanish Parents, Children, and Adolescents Respond

Background: During the COVID-19 pandemic, lockdown strategies have been widely used to contain SARS-CoV-2 virus spread. Children and adolescents are especially vulnerable to suffering psychological effects as result of such measures. In Spain, children were enforced to a strict home lockdown for 42 days during the first wave. Here, we studied the effects of lockdown in children and adolescents through an online questionnaire.

Methods: A cross-sectional study was conducted in Spain using an open online survey from July (after the lockdown resulting from the first pandemic wave) to November 2020 (second wave). We included families with children under 16 years-old living in Spain. Parents answered a survey regarding the lockdown effects on their children and were instructed to invite their children from 7 to 16 years-old (mandatory scholar age in Spain) to respond a specific set of questions. Answers were collected through an application programming interface system, and data analysis was performed using R.

Results: We included 1,957 families who completed the questionnaires, covering a total of 3,347 children. The specific children's questionnaire was completed by 167 kids (7–11 years-old), and 100 adolescents (12–16 years-old). Children, in general, showed high resilience and capability to adapt to new situations. Sleeping problems were reported in more than half of the children (54%) and adolescents (59%), and these were strongly associated with less time doing sports and spending more than 5 h per day using electronic devices. Parents perceived their children to gain weight (41%), be more irritable and anxious (63%) and sadder (46%). Parents and children differed significantly when evaluating children's sleeping disturbances.

Conclusions: Enforced lockdown measures and isolation can have a negative impact on children and adolescent's mental health and well-being. In future waves of the current pandemic, or in the light of potential epidemics of new emerging infections, lockdown measures targeting children, and adolescents should be reconsidered taking into account their infectiousness potential and their age-specific needs, especially to facilitate physical activity and to limit time spent on electronic devices.

Antibody conversion rates to SARS-CoV-2 in saliva from children attending summer schools in Barcelona, Spain

BACKGROUND

Surveillance tools to estimate viral transmission dynamics in young populations are essential to guide recommendations for school opening and management during viral epidemics. Ideally, sensitive techniques are required to detect low viral load exposures among asymptomatic children. We aimed to estimate SARS-CoV-2 infection rates in children and adult populations in a school-like environment during the initial COVID-19 pandemic waves using an antibody-based field-deployable and non-invasive approach.

METHODS

Saliva antibody conversion defined as ≥ 4-fold increase in IgM, IgA, and/or IgG levels to five SARS-CoV-2 antigens including spike and nucleocapsid constructs was evaluated in 1509 children and 396 adults by high-throughput Luminex assays in samples collected weekly in 22 summer schools and 2 pre-schools in 27 venues in Barcelona, Spain, from June 29th to July 31st, 2020.

RESULTS

Saliva antibody conversion between two visits over a 5-week period was 3.22% (49/1518) or 2.36% if accounting for potentially cross-reactive antibodies, six times higher than the cumulative infection rate (0.53%) assessed by weekly saliva RT-PCR screening. IgG conversion was higher in adults (2.94%, 11/374) than children (1.31%, 15/1144) (p=0.035), IgG and IgA levels moderately increased with age, and antibodies were higher in females. Most antibody converters increased both IgG and IgA antibodies but some augmented either IgG or IgA, with a faster decay over time for IgA than IgG. Nucleocapsid rather than spike was the main antigen target. Anti-spike antibodies were significantly higher in individuals not reporting symptoms than symptomatic individuals, suggesting a protective role against COVID-19.

CONCLUSION

Saliva antibody profiling including three isotypes and multiplexing antigens is a useful and user-friendlier tool for screening pediatric populations to detect low viral load exposures among children, particularly while they are not vaccinated and vulnerable to highly contagious variants, and to recommend public health policies during pandemics.

COVID-19 pandemic. What have we learned?

Since the COVID-19 pandemic was declared in March 2020, we have learned a lot about the SARS-CoV-2 coronavirus, and its role in pediatric pathology. Children are infected in a rate quite similar to adults, although in most cases they suffer mild or asymptomatic symptoms. Around 1% of those infected require hospitalization, less than 0.02% require intensive care, and mortality is very low and generally in children with comorbidities. The most common clinical diagnoses are upper or lower respiratory infections, gastrointestinal infection and, more seriously, multisystemic inflammatory syndrome (MIS-C). Most episodes do not require treatment, except for MIS-C. Remdesivir has been widely used as a compassionate treatment and its role has yet to be defined. The newborn can become infected, although vertical transmission is very low (<1%) and it has been shown that the baby can safely cohabit with its mother and be breastfed. In general, neonatal infections have been mild. Primary care has supported a very important part of the management of the pandemic in pediatrics. There has been numerous collateral damage derived from the difficulty of access to care and the isolation suffered by children. The mental health of the pediatric population has been seriously affected. Although it has been shown that schooling has not led to an increase in infections, but rather the opposite. It is essential to continue maintaining the security measures that make schools a safe place, so necessary not only for children's education, but for their health in general.

[COVID-19 pandemic. What have we learned?]

Since the COVID-19 pandemic was declared in March 2020, we have learned a lot about the SARS-CoV-2 coronavirus, and its role in pediatric pathology.Children are infected in a rate quite similar to adults, although in most cases they suffer mild or asymptomatic symptoms. Around 1% of those infected require hospitalization, less than 0.02% require intensive care, and mortality is very low and generally in children with comorbidities. The most common clinical diagnoses are upper or lower respiratory infections, gastrointestinal infection and, more seriously, multisystemic inflammatory syndrome (MIS-C). Most episodes do not require treatment, except for MIS-C. Remdesivir has been widely used as a compassionate treatment and its role has yet to be defined.The newborn can become infected, although vertical transmission is very low (<1%) and it has been shown that the baby can safely cohabit with its mother and be breastfed. In general, neonatal infections have been mild.Primary care has supported a very important part of the management of the pandemic in pediatrics. There has been numerous collateral damage derived from the difficulty of access to care and the isolation suffered by children. The mental health of the pediatric population has been seriously affected. Although it has been shown that schooling has not led to an increase in infections, but rather the opposite. It is essential to continue maintaining the security measures that make schools a safe place, so necessary not only for children's education, but for their health in general.

Factors affecting the transmission of SARS-CoV-2 in school settings

BACKGROUND

Several studies have reported SARS-CoV-2 outbreaks in schools, with a wide range of secondary attack rate (SAR; range: 0-100%). We aimed to examine key risk factors to better understand SARS-CoV-2 transmission in schools.

METHODS

We collected records of 39 SARS-CoV-2 school outbreaks globally published through July 2021 and compiled information on hypothesized risk factors. We utilized the directed acyclic graph (DAG) to conceptualize risk mechanisms, used logistic regression to examine each risk-factor group, and further built multi-risk models.

RESULTS

The best-fit model showed that the intensity of concurrent community transmission (adjusted odds ratio [aOR]: 1.2, 95% CI: 1.17 - 1.24, for each increase of 1 case per 10,000 persons per week), individualism (aOR: 1.72, 95% CI: 1.19 - 2.5, above vs. below the median) were associated higher risk, whereas preventive measures (aOR: 0.22, 95% CI: 0.17 - 0.29, distancing and masking vs. none) and higher population immunity (aOR: 0.28, 95% CI: 0.22 - 0.35) were associated with lower risk of SARS-CoV-2 transmission in schools. Compared to students in pre-schools, the aOR was 0.35 (95% CI: 0.23 - 0.54) for students in primary schools and 1.3 (95% CI: 0.9 - 1.88) for students in high schools.

CONCLUSIONS

Preventive measures in schools (e.g. social distancing and mask-wearing) and communal efforts to lower transmission and increase vaccination uptake (i.e. vaccine-induced population immunity) in the community should be taken to collectively reduce transmission and protect children in schools. Flexible reopening policies may be considered for different levels of schools given their risk differences.

Preventing COVID-19 in assisted living facilities: An impossible task pending vaccination roll out

Here, we aimed to describe the clinical outcomes of the residents of a long-term care facility during its closure to visitors and suppliers in response to the first COVID-19 pandemic from February 23 to June 22, 2020, and the results of the facility-wide SARS-CoV-2 testing of residents and staff in June 2020 before its partially reopening. Seventy-four residents and 53 members of staff were included in the present study. The staff underwent nasopharyngeal swab tests for SARS-CoV-2, and both the staff and residents underwent serological tests to detect IgG antibodies against SARS-CoV-2. The results of all of the tests were negative. Conversely, 94% of residents and 38% members of the staff were tested positive to the nasopharyngeal swab tests during the second COVID-19 pandemic wave (data collected from November 1 to November 30, 2020). Our experience suggests that, in the presence of a life-threatening pandemic such as SARS-CoV-2 infection, the prompt use of restrictive procedures can prevent the spread and progression of disease in assisted living facilities in the short term but may fail in the long term, especially when the prevalence of the COVID-19 greatly increased outside the facility enhancing the risk of import the disease from outside. SARS-CoV-2 vaccination of residents and staff members would contribute to control/limit the prevalence and the spread of the virus.

Upper respiratory tract SARS-CoV-2 RNA loads in symptomatic and asymptomatic children and adults

OBJECTIVES

Studies comparing SARS-CoV-2 RNA load in the upper respiratory tract (URT) between children and adults, either presenting with COVID-19 or asymptomatic have yielded inconsistent results. Here, we conducted a retrospective, single center study to address this issue.

PATIENTS AND METHODS

1,184 consecutive subjects (256 children and 928 adults) testing positive for SARS-COV-2 RNA in nasopharyngeal exudates (NP), of whom 424 (121 children and 303 adults) had COVID-19 and 760 (135 children and 625 adults) were asymptomatic close contacts of COVID-19 patients. SARS-CoV-2 RNA testing was carried out using the TaqPath COVID-19 Combo Kit (Thermo Fisher Scientific, MS, USA). The AMPLIRUN® TOTAL SARS-CoV-2 RNA Control (Vircell SA, Granada, Spain) was used for estimating SARS-CoV-2 RNA loads (in copies/mL). SARS-CoV-2 RNA loads at the time of laboratory diagnosis (single specimen/patient) were used for comparison purposes.

RESULTS

Median initial SARS-COV-2 RNA load was lower (P=0.094) in children (6.98 log₁₀ copies/ml; range, 3.0-11.7) than in adults (7.14 log₁₀ copies/ml; range, 2.2.-13.4) with COVID-19. As for asymptomatic individuals, median SARS-CoV-2 RNA load was comparable (P=0.97) in children (6.20 log₁₀ copies/ml; range, 1.8-11.6) and adults (6.48 log₁₀ copies/ml; range, 1.9-11.8). Children with COVID-19 symptoms displayed SARS-CoV-2 RNA loads (6.98 log₁₀ copies/ml; range, 3.0-11.7) comparable to their asymptomatic counterparts (6.20 log₁₀ copies/ml; range, 1.8-11.6) (P=0.61). Meanwhile in adults, median SARS-CoV-2 RNA load was significantly higher in symptomatic (7.14 log₁₀ copies/ml; range, 2.2.-13.4) than in asymptomatic subjects (6.48 log₁₀ copies/ml; range, 1.9-11.8) (P=<0.001). Overall, a faster URT SARS-CoV-2 RNA clearance rate was observed in children than in adults.

CONCLUSIONS

Based on viral load data at the time of diagnosis, our results suggested that SARS-CoV-2 infected children, with or without COVID-19, may display NP viral loads of comparable magnitude to that found in their adult counterparts; However, children may have shorter viral shedding as compared to adults.