He et al.
The Lancet; doi:10.1016/S0140-6736(21)00238-5
Impact Factor: 60.39 (2019)
Published: 20 March 2021
Background: Wuhan was the epicentre of the COVID-19 outbreak in China. We aimed to determine the seroprevalence and kinetics of anti-SARS-CoV-2 antibodies at population level in Wuhan to inform the development of vaccination strategies.
Methods: In this longitudinal cross-sectional study, we used a multistage, population-stratified, cluster random sampling method to systematically select 100 communities from the 13 districts of Wuhan. Households were systematically selected from each community and all family members were invited to community health-care centres to participate. Eligible individuals were those who had lived in Wuhan for at least 14 days since Dec 1, 2019. All eligible participants who consented to participate completed a standardised electronic questionnaire of demographic and clinical questions and self-reported any symptoms associated with COVID-19 or previous diagnosis of COVID-19. A venous blood sample was taken for immunological testing on April 14–15, 2020. Blood samples were tested for the presence of pan-immunoglobulins, IgM, IgA, and IgG antibodies against SARS-CoV-2 nucleocapsid protein and neutralising antibodies were assessed. We did two successive follow-ups between June 11 and June 13, and between Oct 9 and Dec 5, 2020, at which blood samples were taken.
Findings: Of 4600 households randomly selected, 3599 families (78·2%) with 9702 individuals attended the baseline visit. 9542 individuals from 3556 families had sufficient samples for analyses. 532 (5·6%) of 9542 participants were positive for pan-immunoglobulins against SARS-CoV-2, with a baseline adjusted seroprevalence of 6·92% (95% CI 6·41–7·43) in the population. 437 (82·1%) of 532 participants who were positive for pan-immunoglobulins were asymptomatic. 69 (13·0%) of 532 individuals were positive for IgM antibodies, 84 (15·8%) were positive for IgA antibodies, 532 (100%) were positive for IgG antibodies, and 212 (39·8%) were positive for neutralising antibodies at baseline. The proportion of individuals who were positive for pan-immunoglobulins who had neutralising antibodies in April remained stable for the two follow-up visits (162 [44·6%] of 363 in June, 2020, and 187 [41·2%] of 454 in October–December, 2020). On the basis of data from 335 individuals who attended all three follow-up visits and who were positive for pan-immunoglobulins, neutralising antibody levels did not significantly decrease over the study period (median 1/5·6 [IQR 1/2·0 to 1/14·0] at baseline vs 1/5·6 [1/4·0 to 1/11·2] at first follow-up [p=1·0] and 1/6·3 [1/2·0 to 1/12·6] at second follow-up [p=0·29]). However, neutralising antibody titres were lower in asymptomatic individuals than in confirmed cases and symptomatic individuals. Although titres of IgG decreased over time, the proportion of individuals who had IgG antibodies did not decrease substantially (from 30 [100%] of 30 at baseline to 26 [89·7%] of 29 at second follow-up among confirmed cases, 65 [100%] of 65 at baseline to 58 [92·1%] of 63 at second follow-up among symptomatic individuals, and 437 [100%] of 437 at baseline to 329 [90·9%] of 362 at second follow-up among asymptomatic individuals).
Interpretation: 6·92% of a cross-sectional sample of the population of Wuhan developed antibodies against SARS-CoV-2, with 39·8% of this population seroconverting to have neutralising antibodies. Our durability data on humoral responses indicate that mass vaccination is needed to effect herd protection to prevent the resurgence of the epidemic.
Hansen et al.
The Lancet; doi:10.1016/S0140-6736(21)00575-4
Impact Factor: 60.39 (2019)
Published: 17 March 2021
Background: The degree to which infection with SARS-CoV-2 confers protection towards subsequent reinfection is not well described. In 2020, as part of Denmark's extensive, free-of-charge PCR-testing strategy, approximately 4 million individuals (69% of the population) underwent 10·6 million tests. Using these national PCR-test data from 2020, we estimated protection towards repeat infection with SARS-CoV-2.
Methods: In this population-level observational study, we collected individual-level data on patients who had been tested in Denmark in 2020 from the Danish Microbiology Database and analyzed infection rates during the second surge of the COVID-19 epidemic, from Sept 1 to Dec 31, 2020, by comparison of infection rates between individuals with positive and negative PCR tests during the first surge (March to May, 2020). For the main analysis, we excluded people who tested positive for the first time between the two surges and those who died before the second surge. We did an alternative cohort analysis, in which we compared infection rates throughout the year between those with and without a previous confirmed infection at least 3 months earlier, irrespective of date. We also investigated whether differences were found by age group, sex, and time since infection in the alternative cohort analysis. We calculated rate ratios (RRs) adjusted for potential confounders and estimated protection against repeat infection as 1 – RR.
Findings: During the first surge (i.e., before June, 2020), 533 381 people were tested, of whom 11 727 (2·20%) were PCR positive, and 525 339 were eligible for follow-up in the second surge, of whom 11 068 (2·11%) had tested positive during the first surge. Among eligible PCR-positive individuals from the first surge of the epidemic, 72 (0·65% [95% CI 0·51–0·82]) tested positive again during the second surge compared with 16 819 (3·27% [3·22–3·32]) of 514 271 who tested negative during the first surge (adjusted RR 0·195 [95% CI 0·155–0·246]). Protection against repeat infection was 80·5% (95% CI 75·4–84·5). The alternative cohort analysis gave similar estimates (adjusted RR 0·212 [0·179–0·251], estimated protection 78·8% [74·9–82·1]). In the alternative cohort analysis, among those aged 65 years and older, observed protection against repeat infection was 47·1% (95% CI 24·7–62·8). We found no difference in estimated protection against repeat infection by sex (male 78·4% [72·1–83·2] vs female 79·1% [73·9–83·3]) or evidence of waning protection over time (3–6 months of follow-up 79·3% [74·4–83·3] vs ≥7 months of follow-up 77·7% [70·9–82·9]).
Interpretation: Our findings could inform decisions on which groups should be vaccinated and advocate for vaccination of previously infected individuals because natural protection, especially among older people, cannot be relied on.
Wang et al.
Impact Factor: 42.78 (2019)
Published: 08 March 2021
Abstract: The COVID-19 pandemic has had widespread effects across the globe, and its causative agent, SARS-CoV-2, continues to spread. Effective interventions need to be developed to end this pandemic. Single and combination therapies with monoclonal antibodies have received emergency use authorization and more treatments are under development. Furthermore, multiple vaccine constructs have shown promise, including two that have an approximately 95% protective efficacy against COVID-19. However, these interventions were directed against the initial SARS-CoV-2 virus that emerged in 2019. The recent detection of SARS-CoV-2 variants B.1.1.7 in the UK and B.1.351 in South Africa is of concern because of their purported ease of transmission and extensive mutations in the spike protein. Here we show that B.1.1.7 is refractory to neutralization by most monoclonal antibodies against the N-terminal domain of the spike protein and is relatively resistant to a few monoclonal antibodies against the receptor-binding domain. It is not more resistant to plasma from individuals who have recovered from COVID-19 or sera from individuals who have been vaccinated against SARS-CoV-2. The B.1.351 variant is not only refractory to neutralization by most monoclonal antibodies against the N-terminal domain but also by multiple individual monoclonal antibodies against the receptor-binding motif of the receptor-binding domain, which is mostly due to a mutation causing an E484K substitution. Moreover, compared to wild-type SARS-CoV-2, B.1.351 is markedly more resistant to neutralization by convalescent plasma (9.4-fold) and sera from individuals who have been vaccinated (10.3–12.4-fold). B.1.351 and emergent variants with similar mutations in the spike protein present new challenges for monoclonal antibody therapies and threaten the protective efficacy of current vaccines.
Planas et al.
Nature Medicine; doi:s41591-021-01318-5
Impact Factor: 36.13 (2019)
Published: 26 March 2021
Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.7 and B.1.351 variants were first identified in the United Kingdom and South Africa, respectively, and have since spread to many countries. These variants harboring diverse mutations in the gene encoding the spike protein raise important concerns about their immune evasion potential. Here, we isolated infectious B.1.1.7 and B.1.351 strains from acutely infected individuals. We examined sensitivity of the two variants to SARS-CoV-2 antibodies present in sera and nasal swabs from individuals infected with previously circulating strains or who were recently vaccinated, in comparison with a D614G reference virus. We utilized a new rapid neutralization assay, based on reporter cells that become positive for GFP after overnight infection. Sera from 58 convalescent individuals collected up to 9 months after symptoms, similarly neutralized B.1.1.7 and D614G. In contrast, after 9 months, convalescent sera had a mean sixfold reduction in neutralizing titers, and 40% of the samples lacked any activity against B.1.351. Sera from 19 individuals vaccinated twice with Pfizer Cominarty, longitudinally tested up to 6 weeks after vaccination, were similarly potent against B.1.1.7 but less efficacious against B.1.351, when compared to D614G. Neutralizing titers increased after the second vaccine dose, but remained 14-fold lower against B.1.351. In contrast, sera from convalescent or vaccinated individuals similarly bound the three spike proteins in a flow cytometry-based serological assay. Neutralizing antibodies were rarely detected in nasal swabs from vaccinees. Thus, faster-spreading SARS-CoV-2 variants acquired a partial resistance to neutralizing antibodies generated by natural infection or vaccination, which was most frequently detected in individuals with low antibody levels. Our results indicate that B1.351, but not B.1.1.7, may increase the risk of infection in immunized individuals.
Brauner et al.
Impact Factor: 33.61 (2014); 5-Year Impact Factor: 35.26
Published: 15 December 2020
Although governments are attempting to control the COVID-19 pandemic with nonpharmaceutical interventions (NPIs), there effectiveness at reducing the transmission of COVID-19 is unclear. The authors gathered chronological data on the implementation of NPIs for several European, and other, countries between January and the end of May 2020. The authors then estimated the effectiveness of a range of NPIs, including limiting gathering sizes, business closures, and closure of educational institutions, and stay-at-home-orders. These estimates were completed using Bayesian hierarchical modelling; the authors code is available on GitHub. Closing all educational institutions, limiting gatherings to 10 people or less, and closing face-to-face businesses each reduced transmission considerably. The additional effect of stay-at-home orders was comparatively small.
Limitations: cannot distinguish direct effects on transmission in schools from indirect effects; could not separate out the type of educational settings (university vs. school); doesn’t address preschools or daycare.
Gaffney, Himmelstein, & Woolhander
Annals of Internal Medicine; doi:10.7326/m20-5413
Impact Factor: 21.32 (2019)
Published: 3 November 2020
The authors sought to determine the prevalence of risk factors for severe COVID-19 infection among a group of teachers and adults living with children that are school-aged. The prevalence of risk factors among these two groups were compared to a sample of employed adults that did not work as teachers.
Roughly 40% of teachers had definite risk factors for severe COVID-19 and 51% had definite or possible risk factors for severe COVID-19; this included high body mass index and cardiac conditions, but rarely cancer. When looking at the prevalence among employed adults that were not teachers, roughly 41% had definite risk factors for severe COVID-19 and 56% had definite or possible risk factors for severe COVID-19. This group experienced similar risk factors to teachers, but more were smokers. Of those adults living with school-aged children, roughly 41% had definite risk factors for severe COVID-19 and 54% had definite or possible risk factors for severe COVID-19. Such issues included older age, heart disease, Type 2 Diabetes, and cancer. Follow-up analyses indicated prevalence was similar regardless of younger versus older children being in the home. Those at lower levels of income and adults residing with Black children were found to be at higher risk for COVID-19. Conversely, adults living with Asian American children or children of other races/ethnicities were at the lowest risk of severe COVID-19.
Limitations: only could identify teachers and daycare workers from the survey; could not identify certain conditions that were risk factors for severe COVID-19; estimate is likely low of risk factor prevalence
Murphy et al.
Nature Communications; doi:10.1038/s41467-020-20226-9
Impact Factor: 12.12 (2019)
Published: 04 January 2021
Abstract: Identifying and understanding COVID-19 vaccine hesitancy within distinct populations may aid future public health messaging. Using nationally representative data from the general adult populations of Ireland (N = 1041) and the United Kingdom (UK; N = 2025), we found that vaccine hesitancy/resistance was evident for 35% and 31% of these populations respectively. Vaccine hesitant/resistant respondents in Ireland and the UK differed on a number of sociodemographic and health-related variables but were similar across a broad array of psychological constructs. In both populations, those resistant to a COVID-19 vaccine were less likely to obtain information about the pandemic from traditional and authoritative sources and had similar levels of mistrust in these sources compared to vaccine accepting respondents. Given the geographical proximity and socio-economic similarity of the populations studied, it is not possible to generalize findings to other populations, however, the methodology employed here may be useful to those wishing to understand COVID-19 vaccine hesitancy elsewhere.
Moghadas et al.
Impact Factor: 9.41 (2019)
Published: 28 July 2020
Abstract: Since the emergence of coronavirus disease 2019 (COVID-19), unprecedented movement restrictions and social distancing measures have been implemented worldwide. The socioeconomic repercussions have fueled calls to lift these measures. In the absence of population-wide restrictions, isolation of infected individuals is key to curtailing transmission.
However, the effectiveness of symptom-based isolation in preventing a resurgence depends on the extent of presymptomatic and asymptomatic transmission. We evaluate the contribution of presymptomatic and asymptomatic transmission based on recent individual level data regarding infectiousness prior to symptom onset and the asymptomatic proportion among all infections. We found that the majority of incidences may be attributable to silent transmission from a combination of the presymptomatic stage and asymptomatic infections.
Consequently, even if all symptomatic cases are isolated, a vast outbreak may nonetheless unfold. We further quantified the effect of isolating silent infections in addition to symptomatic cases, finding that over one-third of silent infections must be isolated to suppress a future outbreak below 1% of the population.
Our results indicate that symptom-based isolation must be supplemented by rapid contact tracing and testing that identifies asymptomatic and presymptomatic cases, in order to safely lift current restrictions and minimize the risk of resurgence.
Ehrhardt et al.
Euro Surveillance; doi:10.2807/1560-7917.ES.2020.25.36.2001587
Impact Factor: 6.40 (2019)
Published: 10 September 2020
The authors reviewed data from children infected with severe COVID-19 infections, who had also attended schools and/or childcare facilities. This was done to assess their role in transmitting infections after Germany re opened them in May 2020, until their closure in August 2020. Important to note when examining these data are that childcare facilities, primary schools, and secondary schools within the study all reduced class sizes by 50%, engaging in cleaning of contact surfaces, and regular and interim ventilation by others.
A total of 557 cases of COVID-19 in those age – 19 were detected; of those, 137 were known to have attended childcare or school settings. As noted in the study, 6 of the 137 cases infected a total of 11 additional students (one to three students per case; three in childcare facilities, one in primary school, four in secondary school and three in vocational school), whereas no secondary infections could be detected. To the authors' knowledge, aside from the 11 secondary cases and four students who were infected by two teachers, no other transmission occurred. Based on these results, the authors noted that child-to-child transmission was relatively rare. However, they noted that the low transmission may be in part due to the measures implemented within the schools during re-opening, versus re-opening without such measures. Importantly these classroom sizes had been reduced to half of their normal size. The authors note if larger class sizes are used, there must be strict ventilation of classrooms and face masks should be used both inside and outside of the class.
Limitations: did not include normal sized classes as all were 50%; some data (~18%) did not have school attendance information.
Bearse et al.
Modern Pathology; doi:s41379-021-00790-1
Impact Factor: 6.37 (2019)
Published: 17 March 2021
Abstract: COVID-19 has been associated with cardiac injury and dysfunction. While both myocardial inflammatory cell infiltration and myocarditis with myocyte injury have been reported in patients with fatal COVID-19, clinical–pathologic correlations remain limited. The objective was to determine the relationships between cardiac pathological changes in patients dying from COVID-19 and cardiac infection by SARS-CoV-2, laboratory measurements, clinical features, and treatments. In a retrospective study, 41 consecutive autopsies of patients with fatal COVID-19 were analyzed for the associations between cardiac inflammation, myocarditis, cardiac infection by SARS-CoV-2, clinical features, laboratory measurements, and treatments. Cardiac infection was assessed by in situ hybridization and NanoString transcriptomic profiling. Cardiac infection by SARS-CoV-2 was present in 30/41 cases: virus+ with myocarditis (n = 4), virus+ without myocarditis (n = 26), and virus– without myocarditis (n = 11). In the cases with cardiac infection, SARS-CoV-2+ cells in the myocardium were rare, with a median density of 1 cell/cm2. Virus+ cases showed higher densities of myocardial CD68+ macrophages and CD3+ lymphocytes, as well as more electrocardiographic changes (23/27 vs 4/10; P = 0.01). Myocarditis was more prevalent with IL-6 blockade than with nonbiologic immunosuppression, primarily glucocorticoids (2/3 vs 0/14; P = 0.02). Overall, SARS-CoV-2 cardiac infection was less prevalent in patients treated with nonbiologic immunosuppression (7/14 vs 21/24; P = 0.02). Myocardial macrophage and lymphocyte densities overall were positively correlated with the duration of symptoms but not with underlying comorbidities. In summary, cardiac infection with SARS-CoV-2 is common among patients dying from COVID-19 but often with only rare infected cells. Cardiac infection by SARS-CoV-2 is associated with more cardiac inflammation and electrocardiographic changes. Nonbiologic immunosuppression is associated with lower incidences of myocarditis and cardiac infection by SARS-CoV-2.
Selden, Berdahl, & Fang
Health Affairs; doi:10.1377/hlthaff.2020.01536 Impact Factor: 5.23 (2015)
Published: 3 November 2020
The authors examined the prevalence of risk factors for severe COVID-19 in groups of schools employees and those with school-aged children. Risk factors included within the study were high BMI, aged 65 or older, diabetes, cancer (excluding nonmelanoma skin cancer), emphysema or other chronic obstructive pulmonary disease, kidney disease, and coronary heat disease. The authors also considered factors such as smoking, asthma, and high blood pressure.
Using the definition from the CDC, the authors found that 42% of school employees were at increased risk for severe COVID-19. The most likely staff to be at increased risk were low-skill support staff (58%) compared to teachers/teaching assistants (38%) and administrators/high-skill support staff (39%). The primary risk factor was high BMI, followed by high blood pressure. The results indicated that Black school employees and male school employees were at increase risk for severe COVID-19.
Limitations: only included general population, excluding populations such as healthcare workers, correctional staff, or long-term care residents; did not measure change during pandemic to thinks such as employment, school attendance; likely undercount due to removing some conditions for clarity
Johansson et al.
JAMA Open Network; doi:10.1001/jamanetworkopen.2020.35057
Impact Factor: 5.03 (2019)
Published: 7 January 2021
The authors explored the transmission of COVID-19 among asymptomatic individuals (without symptoms). The effective management of COVID-19 requires effective measures to prevent transmission; however, the use of such measures for asymptomatic cases has been argued by some. Given the potential importance such transmission could play in the pandemic, the proportion of asymptomatic transmission of COVID-19 within the community was explored.
The model within the study incorporated the relative contributions of different types of transmission, including asymptomatic, pre-symptomatic (before symptoms start), and symptomatic individuals. The authors conducted a meta-analysis of existing data and selected the incubation period of 5 days. The infectious period was set at 10 days, and the peak infectiousness was set to vary between 3 – 7 days. These were generally reflective of the existing literature at that time. Across the various models and assumptions (see complete study for details; open access), at least 50% of the new COVID-19 infections were found to have originated from infected individuals without symptoms during the interaction.
Limitations: simple modelling; a range of assumptions were tested, therefore there are a range of potential answers; lack of clarity between asymptomatic and pre-symptomatic people still in the literature; suggests could be lower end of estimate.
Tang et al.
Journal of Affective Disorders; doi:10.1016/j.jad.2020.10.016
Impact Factor: 4.08 (2018)
Published: 15 January 2021
Background: School closures due to the COVID-19 outbreak have affected 87% of the world's students physically, socially, and psychologically, yet rigorous investigation into their mental health during this period is still lacking.
Methods: A cross-sectional online survey of 4-342 primary and secondary school students from Shanghai, China was conducted during March 13-23, 2020. Besides demographic information, psychological distress (including depression, anxiety, and stress), life satisfaction, perceived impact of home quarantine, and parent-child discussions on COVID-19 were assessed.
Results: The three most prevalent symptoms were: anxiety (24.9%), depression (19.7%), and stress (15.2%). Participants were generally satisfied with life and 21.4% became more satisfied with life during school closures. Senior grades were positively correlated with psychopathological symptoms and negatively associated with life satisfaction, whereas the perceived benefit from home quarantine and parent-child discussions on COVID-19 were negatively correlated with psychopathological symptoms and positively correlated with life satisfaction. Among participants who perceived no benefit from home quarantine, those who had discussions with their parents about COVID-19 experienced less depression, anxiety, and stress.
Limitations: Limitations included the inability to infer the casual relationship, no parental report for mental health of children aged 6 to 9, and the inadequate measurement of parent-child discussion.
Conclusions: Mental health problems and resilience co-existed in children and adolescents during the COVID-19 outbreak. Given the important role of parent-child discussions, open communication between parents and children about the pandemic should be encouraged to help children and adolescents cope with mental health problems in public health crisis.
Asgary et al.
BMC Public Health; doi:10.1186/s12889-020-10153-1
Impact Factor: 2.69 (2020)
Published: 12 January 2021
Background: School testing for SARS-CoV-2 infection has become an important policy and planning issue as schools were reopened after the summer season and as the COVID-19 pandemic continues. Decisions to test or not to test and, if testing, how many tests, how often and for how long, are complex decisions that need to be taken under uncertainty and conflicting pressures from various stakeholders.
Method: We have developed an agent-based model and simulation tool that can be used to analyze the outcomes and effectiveness of different testing strategies and scenarios in schools with various number of classrooms and class sizes. We have applied a modified version of a standard SEIR disease transmission model that includes symptomatic and asymptomatic infectious populations, and that incorporates feasible public health measures. We also incorporated a pre-symptomatic phase for symptomatic cases. Every day, a random number of students in each class are tested. If they tested positive, they are placed in self-isolation at home when the test results are provided. Last but not least, we have included options to allow for full testing or complete self-isolation of a classroom with a positive case.
Results: We present sample simulation results for parameter values based on schools and disease related information, in the Province of Ontario, Canada. The findings show that testing can be an effective method in controlling the SARS-CoV-2 infection in schools if taken frequently, with expedited test results and self-isolation of infected students at home.
Conclusions: Our findings show that while testing cannot eliminate the risk and has its own challenges, it can significantly control outbreaks when combined with other measures, such as masks and other protective measures.
Esposito et al.
Italian Journal of Pediatrics; doi:10.1186/s13052-021-00960-6
Impact Factor: 2.10 (5-Year Impact)
Published: 9 January 2021
Background: Although several studies have tried to evaluate the real efficacy of school closure for pandemic control over time, no definitive answer to this question has been given. Moreover, it has not been clarified whether children or teenagers could be considered a problem for SARS-CoV-2 diffusion or, on the contrary, whether parents and school workers play a greater role. The aims of this review are to discuss about children’s safety at school and the better strategies currently able to reduce the risk of SARS-CoV-2 infection at school.
Main Aim: Compared to adults, very few cases of COVID-19 were diagnosed in children, who generally suffered from an asymptomatic infection or a mild disease. Moreover, school closure is systematically associated with the development of problems involving students, teachers and parents, particularly among populations with poor resources. Although several researches have tried to evaluate the real efficacy of school closure for pandemic control over time, no definitive answer to this question has been given. Available findings seem to confirm that to ensure adequate learning and to avoid social and economic problems, schools must remain open, provided that the adults who follow children at home and at school absolutely comply with recommendations for prevention measures and that school facilities can be optimized in order to significantly reduce the spread of infection. In this regard, the universal use of face masks in addition to hand hygiene and safe distancing in schools, at least starting from the age of 6 years, seems extremely useful. Moreover, since the beginning of the COVID-19 outbreak the use of telemedicine to manage suspected SARS-CoV-2-infected individuals in the community has appeared to be an easy and effective measure to solve many paediatric problems and could represent a further support to schools .
Conclusions: We think that schools must remain open, despite COVID-19 pandemic. However, several problems strictly related to school frequency and reduction of infectious risk must be solved before school attendance can be considered completely safe. A single more in-depth guideline agreed between countries with the same school problems could be very useful in eliminating doubts and fostering the compliance of students, teachers and non-teaching school staff reducing errors and misinterpretations.
Lo Moro, Sinigaglia, & Bert
International Journal of Environmental Research and Public Health; doi:10.3390/ijerph17238839
Impact Factor: 2.85 (2019); 5-Year Impact Factor: 3.13 (2019)
Published: 27 November 2020
The authors described the primary measures to be used in the 2020-2021 academic year within the WHO European Region. They also conducted a rapid systematic review of several scientific databases to identify what measures were being used in other regions, including: France, Luxembourg, Malta, Ireland, Italy, Portugal, the UK, Spain, and San Marino. Despite agreement with regards to many of the measures, there was no consensus on specific criteria or methods with which to utilize the different measures.
Based on the rapid systematic review, common measures included at least 1-2 meters between all student desks, compulsory masking for school staff, compulsory masking for secondary school students, and some masking for younger students. Hand hygiene, respiratory etiquette, increased ventilation, and decreased interactions between students were also considered. Recommendations were made to avoid public transport, if possible, and the use of activities that may bring students together, such as canteens. Despite availability of the above measures, there was a lack of clarity on issues such as students returning after testing positive, flexibility of attendance for high-risk children, and school closures.
Limitations: focus on English-only research, state-only guidelines were considered, and rapid reviews can be less extensive and comprehensive than a full systematic review.
Nearchou et al.
International Journal of Environmental Research and Public Health; doi:10.3390/ijerph17228479
Impact Factor: 2.85 (2019) ; 5-Year Impact Factor: 3.13 (2019)
Published: 16 November 2020
The authors used a mixed methods approach to identify and aggregate studies related to mental health on young people aged 18 years old or younger. Within the systematic search, all research designs were considered; the procedure used was the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). Using this procedure, 700 studies were initially identified and after reviewing criteria, 12 studies were selected for analysis.
The findings across the studies indicate that the COVID-19, as expected, has had significant impacts of the mental health of youth. Across the study, higher rates of depression and anxiety were found among adolescents. Specifically, three studies reported rates of depression symptoms ranging from 23 - 44%, while two studies reported rates of anxiety symptoms ranging from 19 – 38%. The authors suggested that emotional reactions and new social regulations, such as social distancing, played a clear role in these changes. Emerging research and the authors suggest that negative emotional reactivity and fear of COVID-19 may be playing a role in this relationship; however, that remains to be further examined.
The results regarding differences in symptoms and age differed depending on study. Some studies found that that younger children tend to react more with fear, clinginess, and somatic (physical such as stomach-ache) symptoms; whereas older adolescents were more likely to present with symptoms of mental distress related to anxiety and depression. Other studies indicated no difference in mental status depending on age of the individual.
Limitations: the studies were not excellent quality, used English-only studies; limited research thus far on this age group
Kim et al.
Archives of Disease in Childhood; doi:10.1136/archdischild-2020-319910
Impact Factor: 3.04 (2019)
Published: 7 August 2020
As children often drive respiratory outbreaks, the authors sought to understand the transmission potential of COVID-19 among children within their household setting. The authors reviewed all index cases of pediatric (18 and under) COVID-19 and their household members from the time period of January to April 2020. Secondary infection was assumed to have occurred if the household member became infected at least 1 day after, but within 14 days of the last time of exposure. Important to note is that as part of outbreak procedure In South Korea, mass screening is utilized, as well as extensive contact tracing. Further, when a pediatric case is confirmed, the child is isolated to the hospital or a community treatment centre.
Within this timeframe, 107 pediatric COVID-19 cases were confirmed, and those children had 248 household members. The authors found that within this study, children rarely transmitted to their family members. Therefore, they noted that when in lockdown and engaged in social distancing, children did not widely transmit to their household members in South Korea.
Limitations: only generalizable to those places that can provide isolation areas once symptoms are showing; took place during lockdown; schools were closed during this time period, minimizing the cases available.
Ruba & Pollak
PLOS ONE; doi:10.1371/journal.pone.0243708
Impact Factor: 2.47 (2019)
Published: 23 December 2020
The World Health Organization has recommended all citizens to wear face covering in the pursuit of managing the COVID-19 pandemic. As some have criticized the suggestion of children wearing masks, the authors sought to examine how face covering may impact the ability of children to make emotional inferences during social interaction. The authors explored this relationship with a sample of racially diverse children aged 7 – 13 years; all children attended publicly funded after-school programs.
Overall, the results indicate that children can successfully wear face coverings with minimal impact during the COVID-19 pandemic. Regarding of using sunglasses or surgical masks, children were able to make accurate emotional inferences even when these parts of the face were covered. The emotion that seemed the most difficult to infer while using a face covering was fear, which was often misinterpreted as surprise. Results were similar regardless of whether the sunglasses or masks were considered, indicating it is unlikely that masks significantly impair children’s ability. Although there may be some challenges, facial coverings are unlikely to dramatically impair a children’s social interactions during the COVID-19 pandemic.
Limitations: the use of additional environmental cues was not investigated; restricted age range.
Li et al.
Journal of Global Health; doi:10.7189/jogh.10.011101
Impact Factor: 2.30 (2019)
Published: June 2020
The authors conducted a rapid review of existing literature to assess the role of children in the transmission of COVID-19. After examining the evidence, 16 unique studies were identified that fit the criteria for further review. These studies included aspects such as transmission by infected children, asymptomatic and symptomatic cases, outbreaks in school settings, and the proportion of children infected.
The authors indicated that there is limited evidence regarding the transmission of COVID-19 among children. They noted that the result broadly indicated that children seem to transmit less often and be infected less often, but that complete blood-based proportion testing is needed. Despite this, other results indicated that children shed the virus for longer through faecal matter increasing the potential of transmission between children.
Limitations: children had limited contacts during time period; there were few studies that were able to answer the question well; more data is needed before it can be aggregated.
Shane et al.
Journal of the Pediatric Infectious Diseases Society; doi:10.1093/jpids/piaa099
Impact Factor: 2.21 (2019)
Published: 9 November 2020
The authors noted that understanding the role that children play in the role of the transmission of COVID-19 is an emerging area of interest. Despite children often being spared from severe clinical COVID-19, understanding their role in the transmission and maintenance of COVID-19 infections is of critical importance to successfully managing the pandemic. Of interest is how asymptomatic and mildly symptomatic infections contribute to household, community, and school transmission patterns.
The authors stated that most children that have tested positive for COVID-19 have been school-aged and adolescents. They noted that cases did occur in infants and young children, but it was a small proportion. The authors acknowledged that estimated the proportion continues to be difficult due to knowing whether children are being appropriately tested. Of importance was that because children tend to manifest less severe disease, those individuals with high viral loads (aka “super-spreaders”) may be less likely to be detected than those of an older age.
Underlying health conditions were common among children that were hospitalized for COVID-19. These included conditions such as chronic respiratory insufficiency, obesity, and neurodevelopmental conditions. Common symptoms for children aged 9 or younger with COVID-19 were fever (46%), cough (37%), headache (15%), diarrhea (14%), and sore throat (13%). For children 10 – 19 the most common symptoms were headache (42%), cough (41%), fever (35%), myalgia (30%), sore throat (29%), shortness of breath (16%), and diarrhea (14%). Severe outcomes related to COVID-19 among children are respiratory failure, multisystemic inflammatory syndrome in children, and purple/red toes. However, most children who suffer from COVID-19 recover completely.
Limitations: limited trials that children have participated in thus far to rely on; research took place prior to the UK variant
Acta Paediatrica; doi:10.1111/apa.15673
Impact Factor: 2.11 (2019)
Accepted: 16 November 2020
The author investigated five Swedish children that experienced long-term symptoms following COVID-19 diagnosis. In addition, the author conducted a systematic review to examine whether other existing literature indicated that this is occurring elsewhere. The authors note that the data regarding long-term COVID is scarce and all that is known so far indicate that a small proportion of children develop hyperinflammation after infection; this hyperinflammation is also termed multi-inflammatory syndrome in children (MIS-C). Therefore, the authors hope to provide a clinical overview of potential long-term COVID-19 symptoms in children, as well as an overview of what the literature has suggested about such experiences thus far.
The five children were aged 9 through 15, and all had experienced symptoms for six months following their clinical diagnoses of COVID-19. Despite none of the children being hospitalized for the COVID-19 infection, all five (100%) experienced fatigue, heart palpitations or chest pain, and laboured breathing. Four (80%) of the children experienced headaches, difficulties concentrating, muscles weakness, dizziness, and sore throats. These issues also resulted in poor school attendance. Although the author engaged in the systematic literature review, no clear information regarding long-term symptoms had been investigated. The author noted that most of the existing literature is focusing on MIS-C within children.
Limitations: does not yield information about the frequency of long-term COVID-19 in children; very small sample size; need to consider predisposing factors; lack of granular data for differential diagnoses.
Girona-Alarcon et al.
BMC Infectious Diseases; doi:10.1186/s12879-021-05786-5
Impact Factor: 1.39 (2019)
Published: 20 January 2021
Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has collapsed health systems worldwide. In adults, the virus causes severe acute respiratory distress syndrome (ARDS), while in children the disease seems to be milder, although a severe multisystem inflammatory syndrome (MIS-C) has been described. The aim was to describe and compare the characteristics of the severe COVID-19 disease in adults and children.
Methods: This prospective observational cohort study included the young adults and children infected with SARS-CoV-2 between March-June 2020 and admitted to the paediatric intensive care unit. The two populations were analysed and compared focusing on their clinical and analytical characteristics and outcomes.
Results: Twenty patients were included. There were 16 adults (80%) and 4 children (20%). No mortality was recorded. All the adults were admitted due to ARDS. The median age was 32 years (IQR 23.3-41.5) and the most relevant previous pathology was obesity (n = 7, 43.7%). Thirteen (81.3%) needed mechanical ventilation, with a median PEEP of 13 (IQR 10.5-14.5). Six (37.5%) needed inotropic support due to the sedation. Eight (50%) developed a healthcare-associated infection, the most frequent of which was central line-associated bloodstream infection (n = 7, 71.4%). One patient developed a partial pulmonary thromboembolism, despite him being treated with heparin. All the children were admitted due to MIS-C. Two (50%) required mechanical ventilation. All needed inotropic support, with a median vasoactive-inotropic score of 27.5 (IQR 17.5-30). The difference in the inotropic requirements between the two populations was statistically significant (37.5% vs. 100%, p < 0.001). The biomarker values were higher in children than in adults: mid-regional pro-adrenomedullin 1.72 vs. 0.78 nmol/L (p = 0.017), procalcitonin 5.7 vs. 0.19 ng/mL (p = 0.023), and C-reactive protein 328.2 vs. 146.9 mg/L (p = 0.005). N-terminal pro-B-type natriuretic peptide and troponins were higher in children than in adults (p = 0.034 and p = 0.039, respectively).
Conclusions: Adults and children had different clinical manifestations. Adults developed severe ARDS requiring increased respiratory support, whereas children presented MIS-C with greater inotropic requirements. Biomarkers could be helpful in identifying susceptible patients, since they might change depending on the clinical features.
Remppis et al.
BMC Infectious Diseases; doi:10.1186/s12879-021-05791-8
Impact Factor: 1.39 (2019)
Published: 1 February 2021
Background: While our knowledge about COVID-19 in adults has rapidly increased, data on the course of disease and outcome in children with different comorbidities is still limited.
Methods: Prospective, observational study at a tertiary care children’s hospital in southern Germany. Clinical and virology data from all paediatric patients admitted with SARS-CoV-2 infection at our hospital were prospectively assessed.
Results: Between March and November 2020, 14 patients were admitted with COVID-19. One patient was admitted a second time with COVID-19 6 months after initial disease. Among seven patients with severe underlying comorbidities, three developed multisystem inflammatory syndrome (MIS-C), two were admitted to the paediatric intensive care unit. One patient needed invasive ventilation. Another patient died shortly after discharge of COVID-19-related complications.
Conclusions: While COVID-19 generally causes mild disease in children, severe respiratory illness and MIS-C occur, in some cases with fatal outcome. Children with underlying diseases might be at special risk for severe disease.