In contrast to other respiratory viruses, children have less severe symptoms when infected with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this review, we discuss proposed hypotheses for the age-related difference in severity of coronavirus disease 2019 (COVID-19).Factors proposed to explain the difference in severity of COVID-19 in children and adults include those that put adults at higher risk and those that protect children. The former include: (1) age-related increase in endothelial damage and changes in clotting function; (2) higher density, increased affinity and different distribution of angiotensin converting enzyme 2 receptors and transmembrane serine protease 2; (3) pre-existing coronavirus antibodies (including antibody-dependent enhancement) and T cells; (4) immunosenescence and inflammaging, including the effects of chronic cytomegalovirus infection; (5) a higher prevalence of comorbidities associated with severe COVID-19 and (6) lower levels of vitamin D. Factors that might protect children include: (1) differences in innate and adaptive immunity; (2) more frequent recurrent and concurrent infections; (3) pre-existing immunity to coronaviruses; (4) differences in microbiota; (5) higher levels of melatonin; (6) protective off-target effects of live vaccines and (7) lower intensity of exposure to SARS-CoV-2.

https://adc.bmj.com/content/archdischild/106/5/429.full.pdf

Why is COVID-19 less severe in children? A review of the proposed mechanisms underlying the age-related difference in severity of SARS-CoV-2 infections.

OBJECTIVE: To undertake a systematic review of reviews of the prevalence of symptoms and signs of COVID-19 in those aged under 20 years. DESIGN: Narrative systematic review of reviews. PubMed, medRxiv, Europe PMC and COVID-19 Living Evidence Database were searched on 9 October 2020. SETTING: All settings, including hospitalised and community settings. PATIENTS: Children and young people (CYP) under age 20 years with laboratory-proven COVID-19. STUDY REVIEW, DATA EXTRACTION AND QUALITY: Potentially eligible articles were reviewed on title and abstract by one reviewer. Quality was assessed using the modified AMSTARS criteria and data were extracted from included studies by two reviewers. MAIN OUTCOME MEASURES: Prevalence of symptoms and signs of COVID-19. RESULTS: 1325 studies were identified and 18 reviews were included. Eight were high quality, 7 medium and 3 low quality. All reviews were dominated by studies of hospitalised children. The proportion of asymptomatic CYP ranged from 14.6% to 42%. Fever and cough were the the most common symptoms; proportions with fever ranged from 46% to 64.2% and with cough from 32% to 55.9%. All other symptoms or signs including rhinorrhoea, sore throat, headache, fatigue/myalgia and gastrointestinal symptoms including diarrhoea and vomiting were infrequent, occurring in less than 10%-20%. CONCLUSIONS: Fever and cough are the most common symptoms in CYP with COVID-19, with other symptoms infrequent. Further research on symptoms in community samples are needed to inform pragmatic identification and testing programmes for CYP.

https://adc.bmj.com/content/archdischild/106/8/802.full.pdf

Systematic review of reviews of symptoms and signs of COVID-19 in children and adolescents.

Objective To undertake a systematic review of reviews of the prevalence of symptoms and signs of COVID-19 in those aged under 20 years? Design Narrative systematic review of reviews. PubMed, medRxiv, Europe PMC and COVID-19 Living Evidence Database were searched on 9 October 2020. Setting All settings, including hospitalised and community settings. Patients CYP under age 20 years with laboratory-proven COVID-19. Study review, data extraction and quality Potentially eligible articles were reviewed on title and abstract by one reviewer. Quality was assessed using the modified AMSTARS criteria and data were extracted from included studies by two reviewers. Main outcome measures Prevalence of symptoms and signs of COVID-19 Results 1325 studies were identified and 18 reviews were included. Eight were high quality, 7 medium and 3 low quality. All reviews were dominated by studies of hospitalised children. The proportion who were asymptomatic ranged from 14.6 to 42%. Fever and cough were the commonest symptoms; proportions with fever ranged from 46 to 64.2% and with cough from 32 to 55.9%. All other symptoms or signs including rhinorrhoea, sore throat, headache, fatigue/myalgia and gastrointestinal symptoms including diarrhoea and vomiting are infrequent, occurring in less than 10-20%. Conclusions Fever and cough are the most common symptoms in CYP with COVID-19, with other symptoms infrequent. Further research on symptoms in community samples are needed to inform pragmatic identification and testing programmes for CYP.

/pdf/systematic-review-of-reviews-of-symptoms-and-signs-of-covid-427wkfap0w.pdf

Systematic review of reviews of symptoms and signs of COVID-19 in children and adolescents

To understand how viruses spread scientists look at two things. One is – on average – how many other people each infected person spreads the virus to. The other is how much variability there is in the number of people each person with the virus infects. Some viruses like the 2009 influenza H1N1, a new strain of influenza that caused a pandemic beginning in 2009, spread pretty uniformly, with many people with the virus infecting around two other people. Other viruses like SARS-CoV-2, the one that causes COVID-19, are more variable. About 10 to 20% of people with COVID-19 cause 80% of subsequent infections – which may lead to so-called superspreading events – while 60-75% of people with COVID-19 infect no one else. Learning more about these differences can help public health officials create better ways to curb the spread of the virus. Chen et al. show that differences in the concentration of virus particles in the respiratory tract may help to explain why superspreaders play such a big role in transmitting SARS-CoV-2, but not the 2009 influenza H1N1 virus. Chen et al. reviewed and extracted data from studies that have collected how much virus is present in people infected with either SARS-CoV-2, a similar virus called SARS-CoV-1 that caused the SARS outbreak in 2003, or with 2009 influenza H1N1. Chen et al. found that as the variability in the concentration of the virus in the airways increased, so did the variability in the number of people each person with the virus infects. Chen et al. further used mathematical models to estimate how many virus particles individuals with each infection would expel via droplets or aerosols, based on the differences in virus concentrations from their analyses. The models showed that most people with COVID-19 infect no one because they expel little – if any – infectious SARS-CoV-2 when they talk, breathe, sing or cough. Highly infectious individuals on the other hand have high concentrations of the virus in their airways, particularly the first few days after developing symptoms, and can expel tens to thousands of infectious virus particles per minute. By contrast, a greater proportion of people with 2009 influenza H1N1 were potentially infectious but tended to expel relatively little infectious virus when the talk, sing, breathe or cough. These results help explain why superspreaders play such a key role in the ongoing pandemic. This information suggests that to stop this virus from spreading it is important to limit crowd sizes, shorten the duration of visits or gatherings, maintain social distancing, talk in low volumes around others, wear masks, and hold gatherings in well-ventilated settings. In addition, contact tracing can prioritize the contacts of people with high concentrations of virus in their airways.

Heterogeneity in transmissibility and shedding SARS-CoV-2 via droplets and aerosols.

An early cause for hope in the coronavirus disease 2019 (COVID19) pandemic was the observation that children are much less likely to experience severe illness than adults.1 This remains true, but has created a perception that children are less susceptible to infection and do not play a substantial role in transmission. In Australia, this perception has been reinforced by assurances from the Prime Minister that schools are safe and that physical distancing is unnecessary in this setting.2 However, emerging research suggests greater caution is needed.

https://onlinelibrary.wiley.com/doi/pdf/10.5694/mja2.50823

COVID-19, children and schools: overlooked and at risk.

BACKGROUND Children with SARS-CoV-2 infection typically have mild symptoms that do not require medical attention, leaving a gap in our understanding of the spectrum of illnesses that the virus causes in children. METHODS We conducted a prospective cohort study of children and adolescents ( RESULTS Of 382 children, 289 (76%) were SARS-CoV-2-infected. SARS-CoV-2-infected children were more likely to be Hispanic (p CONCLUSIONS Hispanic ethnicity and an infected sibling close contact are associated with increased SARS-CoV-2 infection risk among children, while a history of asthma is associated with decreased risk. Age-related differences in the clinical manifestations of SARS-CoV-2 infection must be considered when evaluating children for COVID-19 and in developing screening strategies for schools and childcare settings.

/pdf/sars-cov-2-infections-among-children-in-the-biospecimens-25vcc0k35k.pdf

SARS-CoV-2 Infections Among Children in the Biospecimens from Respiratory Virus-Exposed Kids (BRAVE Kids) Study

Childhood food insecurity increased considerably during the COVID-19 pandemic and is associated with compromised health. Health care systems are increasingly prioritizing food insecurity interventions to improve health, but it is unclear how health systems collaborate with other sectors that are addressing food insecurity. In this study, we aimed to evaluate existing collaborations and explore opportunities for further cross-sector engagement. From December 2020 to March 2021, we conducted semi-structured interviews (N = 34) with informants involved in increasing child food access in North Carolina. Our informants represented different sectors, including community (e.g., food pantry), education (e.g., school lunch program), and government (e.g., Supplemental Nutrition Assistance Program). Rapid qualitative analysis was used to interpret the results and identify themes. Informants rarely mentioned the health care sector as a source of referrals or as a collaborator. Barriers limiting access to food insecurity programs were exacerbated by the COVID-19 pandemic, including lack of transportation, stigma deterring use, limited food choice, and burdensome enrollment processes. Stakeholders recommended mitigating barriers through the expansion of food delivery, co-localization of assistance programs in schools and health care settings, increased food choice, and supporting cross-program enrollment mechanisms. The majority of the stakeholders represented programs from five counties in central North Carolina, with only a few representing statewide initiatives. The COVID-19 pandemic both highlighted the fragmented system of food insecurity organizations and accelerated development of cross-sector collaborations to reduce access barriers. Health care systems are siloed from school and community efforts but have the opportunity to leverage ongoing innovative policy initiatives to construct novel cross-sector models. Such models can better link food insecurity screening with community-based solutions to address family-level food access barriers.

https://ncmedicaljournal.com/article/81278.pdf

Liliana Suarez

Papers

SARS-CoV-2 Infections Among Children in the Biospecimens from Respiratory Virus-Exposed Kids (BRAVE Kids) Study

Cross-Sector Intervention Strategies to Target Childhood Food Insecurity in North Carolina