Long-term outcomes of pediatric infections: from traditional infectious diseases to long covid

Navigating an unfamiliar world - Parents' experiences of having a child with post COVID-19

BACKGROUND

Post COVID-19 diagnosis in children has been difficult as there has been a lack of knowledge within the healthcare system, leading to uncertainty concerning how these children should be assessed and treated. To understand the aspects of how parents experience seeking care for their child with an array of symptoms and how the child's symptoms affect their everyday life and family situation, we need to listen to the parents' stories about having a child living with post COVID-19.

PURPOSE

To describe parents' experiences of seeking professional care for their child with post COVID-19 symptoms and what kinds of impacts there are on their children's daily life.

DESIGN AND METHODS

A qualitative study with an inductive and exploratory approach including seventeen parents of children with post COVID-19. Face-to-face interviews were conducted between October 2022 and March 2023 and analyzed with thematic analysis.

RESULTS

The findings describe how the parents' constant struggle for their child and how the child's symptoms affect their daily life and their family situation in three themes: Navigating the unknown, Navigating life with post COVID-19, and Navigating between fear and hope for an uncertain future.

CONCLUSIONS

This study corroborates the parents' struggle for acceptance of the children's problems in the health system.

PRACTICE IMPLICATIONS

It is important that health care focuses on the everyday world and the problems that the child and parents express to understand the family's perspective and the problems that arise in everyday life.

The lung ultrasound in children with SARS-COV-2 infection: a national multicenter prospective study

Coronavirus disease-19 (COVID-19) caused hospitalizations, severe disease, and deaths in any age, including in the youngest children. The aim of this multicenter national study is to characterize the clinical and the prognostic role of lung ultrasound (LU) in children with COVID-19. We enrolled children between 1 month and 18 years of age with severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection who underwent a LU within 6 h from the first medical evaluation. A total of 213 children were enrolled, 51.6% were male, median age was 2 years and 5 months (interquartile range (IQR) 4 months -11 years and 4 months). One hundred and forty-eight (69.4%) children were admitted in hospital, 9 (6.1%) in pediatric intensive care unit. We found an inverse correlation between the lung ultrasound score (LUS) and the oxygen saturation at the first clinical evaluation (r = -0.16; p = 0.019). Moreover, LUS was significantly higher in patients requiring oxygen supplementation (8 (IQR 3-19) vs 2 (IQR 0-4); p = 0.001). Among LU pathological findings, irregular pleural lines, subpleural consolidations, and pleural effusions were significantly more frequent in patients needing oxygen supplementation (p = 0.007, p = 0.006, and p = 0.001, respectively).  Conclusion: This multicenter study showed that LU in children with COVID-19 can highlight pleural line irregularities, vertical artifacts, and subpleural consolidation. Notably, children with higher LUS have a higher risk of hospitalization and need for oxygen supplementation, supporting LU as a valid and safe point-of-care first level tool for the clinical evaluation of children with COVID-19. What is Known: • Few children infected with SARS-CoV-2 develop a severe disease and need oxygen therapy. • Lung ultrasound can easily detect low respiratory tract infection during SARS-CoV-2. What is New: • Children with higher lung ultrasound score have a higher risk of need for oxygen supplementation. • Irregular pleural line, sub-pleural consolidations and pleural effusions were significantly more frequent in patients needing oxygen supplementation.

Cardiopulmonary Exercise Testing in Children With Long COVID: A Case-controlled Study

BACKGROUND

Cardiopulmonary exercise testing (CPET) is a noninvasive and nonexpensive diagnostic tool, that provides a comprehensive evaluation of the pulmonary, cardiovascular, and skeletal muscle systems' integrated reactions to exercise. CPET has been extensively used in adults with Long COVID (LC), while the evidence about its role in children with this condition is scarce.

METHODS

Prospective, case-controlled observational study. Children with LC and a control group of healthy children underwent CPET. CPET findings were compared within the 2 groups, and within the LC groups according to main clusters of persisting symptoms.

RESULTS

Sixty-one children with LC and 29 healthy controls were included. Overall, 90.2% of LC patients (55 of 61) had a pathologic test vs 10.3% (3/29) of the healthy control. Children with LC presented a statistically significant higher probability of having abnormal values of peak VO2 (P = 0.001), AT% pred (P <0.001), VO2/HR % (P = 0.03), VO2 work slope (P = 0.002), VE/VCO2 slope (P = 0.01). The mean VO2 peak was 30.17 (±6.85) in LC and 34.37 (±6.55) in healthy patients (P = 0.007).

CONCLUSIONS

Compared with healthy controls, children with LC have objective impaired functional capacity (expressed by a low VO2 peak), signs of deconditioning and cardiogenic inefficiency when assessed with CPET. As such, CPET should be routinely used in clinical practice to objectify and phenotype the functional limitations of children with LC, and to follow-up them.

Autonomic cardiac function in children and adolescents with long COVID: a case-controlled study

Although the mechanisms underlying the pathophysiology of long COVID condition are still debated, there is growing evidence that autonomic dysfunction may play a role in the long-term complications or persisting symptoms observed in a significant proportion of patients after SARS-CoV-2 infection. However, studies focused on autonomic dysfunction have primarily been conducted in adults, while autonomic function has not yet been investigated in pediatric subjects. In this study, for the first time, we assessed whether pediatric patients with long COVID present abnormalities in autonomic cardiac function. Fifty-six long COVID pediatric patients (mean age 10.3 ± 3.8 y) and 27 age-, sex-, and body surface area-matched healthy controls (mean age 10.4 ± 4.5y) underwent a standard 12-lead electrocardiography (ECG) and 24-h ECG Holter monitoring. Autonomic cardiac function was assessed by time-domain and frequency-domain heart rate variability parameters. A comprehensive echocardiographic study was also obtained by two-dimensional echocardiography and tissue Doppler imaging. Data analysis showed that pediatric patients with long COVID had significant changes in HRV variables compared to healthy controls: significantly lower r-MSSD (root mean square of successive RR interval differences, 47.4 ± 16.9 versus 60.4 ± 29.1, p = 0.02), significant higher values VLF (very low frequency, 2077.8 ± 1023.3 versus 494.3 ± 1015.5 ms, p = 0.000), LF (low frequency, 1340.3 ± 635.6 versus 354.6 ± 816.8 ms, p = 0.000), and HF (high frequency, 895.7 ± 575.8 versus 278.9 ± 616.7 ms, p = 0.000). No significant differences were observed between the two groups both in systolic and diastolic parameters by echocardiography.  Conclusion: These findings suggest that pediatric patients with long COVID have an imbalance of cardiac autonomic function toward a relative predominance of parasympathetic tone, as already reported in adult patients with long COVID. Further studies are needed to clarify the clinical significance of this autonomic dysfunction and demonstrate its role as a pathophysiological mechanism of long COVID, paving the way for effective therapeutic and preventive strategies. What is Known: • Long Covid in children has been described globally, but studies have mostly focused on collecting the temporal evolution of persisting symptoms. What is New: • Cardiac autonomic imbalance toward a relative predominance of parasympathetic tone is a mechanism underlying Long Covid in children, as also described in adults.

Long COVID in pediatrics-epidemiology, diagnosis, and management

This review summarizes current knowledge on post-acute sequelae of COVID-19 (PASC) and post-COVID-19 condition (PCC) in children and adolescents. A literature review was performed to synthesize information from clinical studies, expert opinions, and guidelines. PASC also termed Long COVID - at any age comprise a plethora of unspecific symptoms present later than 4 weeks after confirmed or probable infection with severe respiratory syndrome corona virus type 2 (SARS-CoV-2), without another medical explanation. PCC in children and adolescents was defined by the WHO as PASC occurring within 3 months of acute coronavirus disease 2019 (COVID-19), lasting at least 2 months, and limiting daily activities. Pediatric PASC mostly manifest after mild courses of COVID-19 and in the majority of cases remit after few months. However, symptoms can last for more than 1 year and may result in significant disability. Frequent symptoms include fatigue, exertion intolerance, and anxiety. Some patients present with postural tachycardia syndrome (PoTS), and a small number of cases fulfill the clinical criteria of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). To date, no diagnostic marker has been established, and differential diagnostics remains challenging. Therapeutic approaches include appropriate self-management as well as the palliation of symptoms by non-pharmaceutical and pharmaceutical strategies.    Conclusion: PASC in pediatrics present with heterogenous severity and duration. A stepped, interdisciplinary, and individualized approach is essential for appropriate clinical management. Current health care structures have to be adapted, and research was extended to meet the medical and psychosocial needs of young people with PASC or similar conditions. What is Known: • Post-acute sequelae of coronavirus 2019 (COVID-19) (PASC) - also termed Long COVID - in children and adolescents can lead to activity limitation and reduced quality of life. • PASC belongs to a large group of similar post-acute infection syndromes (PAIS). Specific biomarkers and causal treatment options are not yet available. What is New: • In February 2023, a case definition for post COVID-19 condition (PCC) in children and adolescents was provided by the World Health Organization (WHO), indicating PASC with duration of at least 2 months and limitation of daily activities. PCC can present as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). • Interdisciplinary collaborations are necessary and have been established worldwide to offer harmonized, multimodal approaches to diagnosis and management of PASC/PCC in children and adolescents.

Comparable Psychotropic Prescription Rates After Hospital Discharge Between Patients with COVID-19 and Those With Non-COVID-19-Related Respiratory Infection

INTRODUCTION

Whether psychiatric symptoms after recovery from coronavirus disease 2019 (COVID-19) are specific to this illness remains unclear.

METHODS

In this retrospective study, the Diagnosis Procedure Combination data and outpatient clinic data were used for patients who received inpatient treatment in Saiseikai-affiliated hospitals for COVID-19 or other respiratory tract infections (non-COVID) from 2020 to 2022. The primary outcome was new prescriptions of psychotropic drugs after discharge (i. e., prescriptions of psychotropics to patients who had not received them before or during their hospitalization). Values of interest were compared between groups using the chi-square test or Fisher's exact test. A COX proportional-hazards model was used to examine factors associated with psychotropic prescriptions after discharge in age- and sex-matched COVID-19 and non-COVID patients.

RESULTS

Of 31,993 chart records, 19,613 were excluded due to a positive history with psychiatric disorders (n=2,445), prescriptions of psychotropics (n=744), and no follow-ups (n=16,424). Thus, 3,648 COVID-19 and 8,732 non-COVID patients were included (mean [range] duration of follow-up, days: 146.9 [1-727] and 239.2 [1-729], respectively). Two hundred and four (5.6%) of the 3,648 patients with COVID-19 received psychotropic prescriptions after discharge. No statistically significant differences were observed in the prescription rates of any psychotropic category between the COVID-19 and non-COVID groups. An increase in severity during hospitalization was significantly associated with more frequent psychotropic prescriptions (hazard ratio 1.83, p<0.001).

DISCUSSION

The development of psychiatric symptoms should be closely observed, especially in patients who experienced increased severity during hospitalization, regardless of whether they suffered from COVID-19.

How does post COVID differ from other post-viral conditions in childhood and adolescence (0-20 years old)? A systematic review

Background

Post Coronavirus disease (COVID) and other post-viral infection syndromes present an overlap of pathogenesis, onset, progression, and symptom profile. We aimed to systematically describe studies on post-viral conditions and determine the entity of post COVID compared to other post-viral conditions in children.

Methods

We conducted a systematic search of the Embase, MEDLINE, Cochrane Library, and GoogleScholar databases (January 1946-3 November 2023), according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The main outcomes were differences in condition duration, symptom type, and development of chronic symptoms. This systematic review was registered on PROSPERO (CRD42023401789).

Findings

35/5051 studies were included, with 42,934 children, adolescents and young adults (0-20 years old) overall. Twenty-eight studies focused on post COVID symptoms, followed by five papers on Respiratory Syncytial Virus (RSV) and Rhinovirus, one study on Epstein-Barr Virus (EBV), and one on gastrointestinal viruses. Studies on post COVID mainly reported data on older children/adolescents, describing long-lasting symptoms, including fatigue, neurologic, cardiorespiratory, musculoskeletal, mental health, and gastrointestinal symptoms. The maximum described symptoms duration was eighteen months, with an average follow-up of seven months. The development of chronic symptoms was reported by 30 studies (93.8%) for 10,473/28,474 patients (36.8%). Recovery was achieved in 18,001/28,474 cases (63.2%). The study on EBV reported persistent fatigue in adolescents for a similar duration (6 months, 46% chronic). Studies on RSV and Rhinovirus were mainly done in children under three years, with development of recurrent wheezing (up to 3 years).

Interpretation

Post-viral fatigue was a shared feature between post COVID and post EBV conditions. A better understanding of post COVID as a unique condition, sharing features with other post-viral syndromes, is needed. The healthcare burden and socio-economic consequences for children and their families warrant further investigation and development of appropriate healthcare management plans. The foremost requirement is the establishment of consistent and shareable definitions, as well as a consensus on outcomes, to effectively evaluate follow-up and quantify the burden of different viral infections.

Funding

EU Horizon, EDCTP, NIH.

International Care programs for Pediatric Post-COVID Condition (Long COVID) and the way forward

BACKGROUND

Pediatric Post-COVID-Condition (PPCC) clinics treat children despite limited scientific substantiation. By exploring real-life management of children diagnosed with PPCC, the International Post-COVID-Condition in Children Collaboration (IP4C) aimed to provide guidance for future PPCC care.

METHODS

We performed a cross-sectional international, multicenter study on used PPCC definitions; the organization of PPCC care programs and patients characteristics. We compared aggregated data from PPCC cohorts and identified priorities to improve PPCC care.

RESULTS

Ten PPCC care programs and six COVID-19 follow-up research cohorts participated. Aggregated data from 584 PPCC patients was analyzed. The most common symptoms included fatigue (71%), headache (55%), concentration difficulties (53%), and brain fog (48%). Severe limitations in daily life were reported in 31% of patients. Most PPCC care programs organized in-person visits with multidisciplinary teams. Diagnostic testing for respiratory and cardiac morbidity was most frequently performed and seldom abnormal. Treatment was often limited to physical therapy and psychological support.

CONCLUSIONS

We found substantial heterogeneity in both the diagnostics and management of PPCC, possibly explained by scarce scientific evidence and lack of standardized care. We present a list of components which future guidelines should address, and outline priorities concerning PPCC care pathways, research and international collaboration.

IMPACT

Pediatric Post-COVID Condition (PPCC) Care programs have been initiated in many countries. Children with PPCC in different countries are affected by similar symptoms, limiting many to participate in daily life. There is substantial heterogeneity in diagnostic testing. Access to specific diagnostic tests is required to identify some long-term COVID-19 sequelae. Treatments provided were limited to physical therapy and psychological support. This study emphasizes the need for evidence-based diagnostics and treatment of PPCC. The International Post-COVID Collaboration for Children (IP4C) provides guidance for guideline development and introduces a framework of priorities for PPCC care and research, to improve PPCC outcomes.

Persisting Gastrointestinal Symptoms in Children with SARS-CoV-2: Temporal Evolution over 18 Months and Possible Role of Lactoferrin

BACKGROUND AND AIM

Persisting gastrointestinal symptoms are reported to be relatively common in children with long COVID; however, their detailed characterization and long-term outcomes have not yet been described.

METHODS

We performed a retrospective study aiming to investigate the temporal evolution of gastrointestinal symptoms in children with SARS-CoV-2, from acute infection to 18-months follow-up. To further investigate possible therapeutic strategies, we evaluated the role of lactoferrin in improving gastrointestinal symptoms in these children, compared with those not treated.

RESULTS

A total of 1224 patients (47.7% females) were included. Of these participants, 246 (19.8%) were vaccinated and 143 (11.5%) presented with comorbidities. A total of 175 patients (14.1%) presented gastrointestinal symptoms during acute infection, 54 (4.4%) at three months, 23 (1.9%) at six months, 6 (3.3%) at twelve months, and 2 (2.3%) at eighteen months follow-up. At six months follow-up, children who were treated with 3 months oral lactoferrin had less persisting symptoms compared to those who did not receive lactoferrin, although this difference was not statistically significant (three patients (25%) in the lactoferrin group vs. fourteen patients (33.3%) not treated, p = 0.73), probably due to the low number of patients with persisting GI symptoms.

CONCLUSIONS

GI symptoms are relatively common during acute SARS-CoV-2 infection in children, and a non-negligible proportion of these children reported persisting symptoms for up to 12-18 months after the acute infection. In addition, we found a trend even if statistically nonsignificant toward faster improvement of persisting gastrointestinal symptoms in children with long COVID treated with lactoferrin. Despite the limitations relating to the present study's design, given the significant burden of gastrointestinal symptoms in children with long COVID, our findings provide the basis to perform a prospective, placebo-controlled study.

Intrinsic factors behind long COVID: III. Persistence of SARS-CoV-2 and its components

Considerable research has been done in investigating SARS-CoV-2 infection, its characteristics, and host immune response. However, debate is still ongoing over the emergence of post-acute sequelae of SARS-CoV-2 infection (PASC). A multitude of long-lasting symptoms have been reported several weeks after the primary acute SARS-CoV-2 infection that resemble several other viral infections. Thousands of research articles have described various post-COVID-19 conditions. Yet, the evidence around these ongoing health problems, the reasons behind them, and their molecular underpinnings are scarce. These persistent symptoms are also known as long COVID-19. The persistence of SARS-CoV-2 and/or its components in host tissues can lead to long COVID. For example, the presence of viral nucleocapsid protein and RNA was detected in the skin, appendix, and breast tissues of some long COVID patients. The persistence of viral RNA was reported in multiple anatomic sites, including non-respiratory tissues such as the adrenal gland, ocular tissue, small intestine, lymph nodes, myocardium, and sciatic nerve. Distinctive viral spike sequence variants were also found in non-respiratory tissues. Interestingly, prolonged detection of viral subgenomic RNA was observed across all tissues, sometimes in multiple tissues of the same patient, which likely reflects recent but defective viral replication. Moreover, the persistence of SARS-CoV-2 RNA was noticed throughout the brain at autopsy, as late as 230 days following symptom onset among unvaccinated patients who died of severe infection. Here, we review the persistence of SARS-CoV-2 and its components as an intrinsic factor behind long COVID. We also highlight the immunological consequences of this viral persistence.

Long COVID and rehabilitation

Coronavirus disease 2019 (COVID-19) has caused tremendous morbidity and mortality worldwide. The large number of post-COVID survivors has drawn attention to the management of post-COVID condition, known as long COVID. This review examines current knowledge of long COVID, regarding its epidemiology, mechanism, and clinical presentations in both adults and children. We also review the rehabilitation principles, modules, and effects, and share Taiwan's efforts to provide a top-down, nationwide care framework for long COVID patients. Dyspnea, chronic cough, and fatigue are the most commonly reported symptoms in the first 6 months after infection, but cognitive impairment and psychological symptoms may persist beyond this time. Several possible mechanisms behind these symptoms were proposed, but remained unconfirmed. These symptoms negatively impact individuals' function, activities, participation and quality of life. Rehabilitation is a key element of management to achieve functional improvement. Early management should start with comprehensive evaluation and identification of red flags. Exercise-based therapy, an essential part of management of long COVID, can be conducted with different modules, including telerehabilitation. Post-exertional symptom exacerbation and orthostatic hypotension should be carefully monitored during exercise. Randomized control trials with a large sample size are needed to determine the optimal timing, dosage, and modules.

Susceptibility of SARS-CoV2 infection in children

Coronavirus disease 2019 in children presents with distinct phenotype in comparison to adults. Overall, the pediatric infection with a generally milder clinical course of the acute infection compared to adults still faces several unknown aspects. Specifically, the presence of a wide range of inflammatory manifestations, including multisystem inflammatory syndrome in children (MIS-C), myocarditis, and long COVID in the period after infection suggests a particular susceptibility of some children upon severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Albeit peculiar complications such as long covid are less frequent in children compared to adults, research on the relationship between inflammatory syndromes and SARS-CoV-2 is rapidly evolving.     Conclusions: new studies and findings continue to emerge, providing further insights into the underlying mechanisms and potential therapeutic strategies. In the present work, we revised current knowledge of the main factors accounting for such variability upon SARS-CoV-2 infection over the pediatric age group. What is Known: • COVID19 in children overall showed a milder course compared to adults during the acute phase of the infection. • Children showed to be susceptible to a wide range of post infectious complications including multisystem inflammatory syndrome in children (MIS-C), myocarditis, neuroinflammation, and long COVID. What is New: • Mechanisms underlying susceptibility to a severe course of the infection were recently shown to pertain to the host. • A specific combination of HLA was recently shown to be associated to higher susceptibility to MIS-C in children.

Long COVID in children and adolescents: prevalence, clinical manifestations, and management strategies

Long coronavirus disease (COVID), also known as postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection, has been defined as signs and symptoms which persist for 4 weeks or even lasting for 6 months after the initial infection. Although the prevalence of long COVID in children is currently unknown, epidemiological investigations have reported cases in pediatric populations. Clinical manifestations of long COVID in children include respiratory symptoms, such as cough and dyspnea, as well as neuropsychiatric and general conditions, including fatigue, headache, and muscle weakness. The pathophysiology of long COVID in children is still being investigated, but potential mechanisms include viral persistence, autoimmunity, and neuroinflammation. Risk factors for long COVID in children are not yet well understood, but studies have suggested that children with a history of severe acute COVID-19 infection or comorbidities may be at increased risk. Evaluation for respiratory symptoms of long COVID in children is essential, including spirometry and imaging studies to assess lung function and any potential damage. Furthermore, long COVID in children has been associated with a higher prevalence of mental health problems than in adults, emphasizing the importance of monitoring and addressing these aspects in pediatric patients. Although our understanding of long COVID in children and adolescents is still evolving, it is clear that the condition can have significant impacts on their health and well-being. The aim of this review is to synthesize the current knowledge on the prevalence, risk factors, and pathophysiology of long COVID in children and adolescents, and to discuss potential management strategies based on existing evidence.

Effect of Water-Based vs. Land-Based Exercise Intervention (postCOVIDkids) on Exercise Capacity, Fatigue, and Quality of Life in Children with Post COVID-19 Condition: A Randomized Controlled Trial

Evidence suggests that COVID-19 can cause lasting health consequences called post-COVID-19 condition. We conducted a three-group, randomized controlled trial for children aged 10-12 years with post COVID-19 condition. Participants were randomized to AQUA, LAND, or CONTROL groups. The AQUA and LAND training sessions were conducted twice a week for eight weeks. The primary outcomes were exercise capacity, measured using the modified Balke treadmill protocol, and fatigue, measured using the Cumulative Fatigue Symptoms Questionnaire (CFSQ). The secondary outcome was health-related quality of life (HRQoL), measured with the Pediatric Quality of Life Inventory (PedsQL) for children and parents. A total of 74 of the 86 children completed the intervention and attended the post-intervention assessment. The absolute maximal oxygen uptake (VO2max) values increased after both AQUA (p = 0.001) and LAND (p = 0.004) interventions. No significant differences were found in the degree of total fatigue and individual fatigue symptoms. A significant improvement was found in the PedsQL reported by the parents in the LAND group. In conclusion, the applied eight-week water-based and land-based exercise training programs improved exercise capacity in children aged 10-12 years old with post COVID-19 condition. The parents of the children in the training groups also noted an improvement in HRQoL.

Social Stigma in Children with Long COVID

There is growing evidence that adults with Long COVID suffer from different sets of stigmata related to their condition. In children with Long COVID, this aspect has never been investigated. This study aims to investigate if children with Long COVID also experience stigma.

METHODS

Children with a previous SARS-CoV-2 infection evaluated at 3 month follow-ups in a pediatric post COVID unit were asked to fill in an online Long COVID Stigma Scale survey before they were assessed by a pediatrician. Doctors were unaware of children's responses when they performed a diagnosis of Long COVID or full recovery from previous infection, according to the World Health Organization definition of pediatric Long COVID. Responses to the Stigma scale were then compared in the two cohorts of children.

RESULTS

224 patients responded to the questionnaire; 40 patients were diagnosed with Long COVID. Children with Long COVID significantly more frequently felt embarrassed about having Long COVID (p 0.035), felt embarrassed about having physical limitations (p < 0.001), felt they were valued less due to Long COVID (p 0.003), felt they were different from other peers due to Long COVID (p 0.033), felt significantly more frequently that people behaved differently towards them because they might be lying since the diagnosis of Long COVID (p 0.006), that they were less respected by others due to Long COVID (p 0.017), that other people thought that Long COVID is not a real disease (p 0.007), that other people thought that developing Long COVID is a sign of weakness (p 0.008), and that other people might judge them negatively due to their diagnosis of Long COVID (p < 0.001).

CONCLUSIONS

Children with Long COVID, similar to adults, are suffering from stigmata due to their condition,. These data may have implication and should be used by the public, policy makers, and healthcare professionals regarding pediatric Long COVID.

Revolutionizing antiviral therapy with nanobodies: Generation and prospects

As the world continues to grapple with infectious diseases, scientists are constantly searching for effective ways to combat these deadly pathogens. One promising avenue of research is the use of nanobodies as neutralization agents. These small proteins, derived from camelid antibodies, have several unique advantages over traditional antibodies, including their small size. Nanobodies are much smaller than conventional antibodies, typically weighing in at around 15 kDa compared to the 150 kDa of a typical human antibody. This small size allows them to penetrate into tight spaces that larger molecules cannot reach, such as the crevices on the surface of viruses or bacteria. This makes them highly effective at neutralizing viruses by binding to and blocking their key functional sites. In this mini-review we discuss the construction approaches of nanobodies, and some methods to increase the half-life of nanobodies. Moreover, we discuss Nanobodies and their therapeutic potential for infectious agents.

Persistent respiratory symptoms associated with post-Covid condition (Long Covid) in children: a systematic review and analysis of current gaps and future perspectives

INTRODUCTION

There is increasing evidence that also children can develop Long Covid. However, there are no specific reviews providing a clear description of reported respiratory symptoms and potential diagnostics.

AREAS COVERED

We performed on PubMed a systematic search of studies conducted on children aged less than 18 years with previous SARS-CoV-2 infection complaining about persistent respiratory symptoms; the aim of our review is to characterize the incidence, pattern and duration of respiratory symptoms after the acute infection in pediatric population.

EXPERT OPINION

Children can develop persisting respiratory symptoms, as documented by several follow-up studies both including or not control groups of non-infected children. However, the methodological variabilities of the analyzed studies does not allow to provide firm conclusions about the rate, type and best diagnostics for children with persistent respiratory symptoms. Future studies should investigate on larger pediatric cohorts the role of noninvasive diagnostics and new biomarkers as well as investigating therapeutic options both during acute infection or when Long Covid has been diagnosed.

Long COVID in Children: A Multidisciplinary Review

Long COVID syndrome has emerged as a long-lasting consequence of acute SARS-CoV-2 infection in adults. In addition, children may be affected by Long COVID, with potential clinical issues in different fields, including problems in school performance and daily activities. Yet, the pathophysiologic bases of Long COVID in children are largely unknown, and it is difficult to predict who will develop the syndrome. In this multidisciplinary clinical review, we summarise the latest scientific data regarding Long COVID and its impact on children. Special attention is given to diagnostic tests, in order to help the physicians to find potential disease markers and quantify impairment. Specifically, we assess the respiratory, upper airways, cardiac, neurologic and motor and psychological aspects. Finally, we also propose a multidisciplinary clinical approach.

Case report: Post-COVID new-onset neurocognitive decline with bilateral mesial-temporal hypometabolism in two previously healthy sisters

Background

Long coronavirus disease (COVID) is increasingly recognized in adults and children; however, it is still poorly characterized from a clinical and diagnostic perspective, particularly in the younger populations.

Case presentation

We described the story of two sisters-with high social and academic performance before their severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-who reported severe neurocognitive problems, initially classified as psychologic pandemic distress and eventually found to have significant brain hypometabolism.

Conclusions

We provided a detailed clinical presentation of neurocognitive symptoms in two sisters with long COVID associated with brain hypometabolism documented in both sisters. We believe that the evidence of objective findings in these children further supports the hypothesis that organic events cause persisting symptoms in a cohort of children after SARS-CoV-2 infection. Such findings highlight the importance of discovering diagnostics and therapeutics.

Role of Lung Ultrasound in the Follow-Up of Children with Previous SARS-CoV-2 Infection: A Case-Control Assessment of Children with Long COVID or Fully Recovered

Lung ultrasound (LUS) can detect lower respiratory tract involvement in children with acute SARS-CoV-2 infection. However, its role in follow-up assessments is still unclear. To describe LUS findings in children after SARS-CoV-2 infection, we conducted a prospective study in a population of pediatric patients referred to the post-COVID unit in a tertiary center during the study period from February 2021 to May 2022. Children were classified as recovered from acute infection or with persisting symptoms. LUS was performed in all children and a LUS score (ranging from 0 to 36 points) was calculated according to the Italian Academy of Thoracic Ultrasound. Six hundred forty-seven children (304 females, 47%) were enrolled. The median follow-up evaluation was two months. The median age was 7.9 (IQR: 6) years. At the follow-up evaluation, 251 patients (38.8%) had persistent symptoms, of whom 104 (16.1%) had at least one respiratory symptom. The median LUS level was 2 (IQR: 4). LUS findings and LUS scores did not differ in children with Long COVID compared to the group of children fully recovered from the initial infection. In conclusion, after SARS-CoV-2 infection, LUS was mostly normal or showed minimal artifacts in all groups of children.

Risk factors for post-COVID-19 condition (Long Covid) in children: a prospective cohort study

Background

Adults and children can develop post-Covid-19 condition (PCC) (also referred to as Long Covid). However, existing evidence is scarce, partly due to a lack of a standardised case definition, short follow up duration, and heterogenous study designs, resulting in wide variation of reported outcomes. The primary aim of this study was to characterise risk factors for PCC and longitudinal rates of recovery in a cohort of children and young people using a standardised protocol.

Methods

We performed a prospective "disease-based" cohort study between 01/02/2020 to 31/10/2022 including children aged 0-18 years old, with a previous diagnosis of Covid-19. Children with microbiologically confirmed SARS-CoV-2 infection, were invited for an in-clinic follow-up assessment at a paediatric post-covid clinic in Rome, Italy, at serial intervals (3-, 6-, 12- and 18-months post-onset). PCC was defined as persistence of otherwise unexplained symptoms for at least three months after initial infection. The statistical association between categorical variables was obtained by Chi-squared tests or Fisher's exact tests. Multivariable logistic regressions are presented using odds ratios (OR) and 95% confidence interval (CI). Survival analysis was conducted using the Kaplan-Meier method.

Findings

1243 children were included, median age: 7.5 (4-10.3) years old; 575 (46.3%) were females. Of these, 23% (294/1243) were diagnosed with PCC at three months post-onset. Among the study population, 143 patients remained symptomatic at six months, 38 at 12 months, and 15 at 18 months follow up evaluation. The following risk factors were associated with PCC: >10 years of age (OR 1.23; 95% CI 1.18-1.28), comorbidities (OR 1.68; 95% CI 1.14-2.50), and hospitalisation during the acute phase (OR 4.80; 95%CI 1.91-12.1). Using multivariable logistic regression, compared to the Omicron variant, all other variants were significantly associated with PCC at 3 and 6 months. At least one dose of vaccine was associated with a reduced, but not statistically significant risk of developing PCC.

Interpretation

In our study, acute-phase hospitalisation, pre-existing comorbidity, being infected with pre-Omicron variants and older age were associated with a higher risk of developing PCC. Most children recovered over time, but one-in-twenty of those with PCC at three months reported persistent symptoms 18 months post-Sars-CoV-2 infection. Omicron infection was associated with shorter recovery times. We did not find a strong protective effect of vaccination on PCC development. Although our cohort cannot be translated to all Italian children with PCC as more nationwide studies are needed, our findings highlight the need of new strategies to prevent and treat pediatric PCC are needed.

Funding

This study has been funded by Pfizer non-competitive grant, granted to DB (# 65925795).

Lung perfusion assessment in children with long-COVID: A pilot study

BACKGROUND

There is increasing evidence that chronic endotheliopathy can play a role in patients with Post-Covid Condition (PCC, or Long Covid) by affecting peripheral vascularization. This pilot study aimed at assessing lung perfusion in children with Long-COVID with ^99m Tc-MAA SPECT/CT.

MATERIALS AND METHODS

lung ^99m Tc-MAA SPECT/CT was performed in children with Long-COVID and a pathological cardiopulmonary exercise testing (CPET). Intravenous injections were performed on patients in the supine position immediately before the planar scan according to the EANM guidelines for lung scintigraphy in children, followed by lung SPECT/CT acquisition. Reconstructed studies were visually analyzed.

RESULTS

Clinical and biochemical data were collected during acute infection and follow-up in 14 children (6 females, mean age: 12.6 years) fulfilling Long-COVID diagnostic criteria and complaining of chronic fatigue and postexertional malaise after mild efforts, documented by CPET. Imaging results were compared with clinical scenarios during acute infection and follow-up. Six out of 14 (42.8%) children showed perfusion defects on ^99m Tc-MAA SPECT/CT scan, without morphological alterations on coregistered CT.

CONCLUSIONS

This pilot investigation confirmed previous data suggesting that a small subgroup of children can develop lung perfusion defects after severe acute respiratory syndrome coronavirus 2 infection. Larger cohort studies are needed to confirm these preliminary results, providing also a better understanding of which children may deserve this test and how to manage those with lung perfusion defects.

Diagnosis and management of post-COVID (Long COVID) in children: a moving target

PURPOSE OF REVIEW

This review describes recent findings about post-COVID condition (PCC, or Long COVID) in children, including current knowledge about its epidemiology, clinical presentation, pathogenesis and care.

RECENT FINDINGS

There is no internationally agreed definition of PCC, although now most researchers agree that it is a complex clinical symptomatology persisting for at least 3 months after COVID-19, without an alternative diagnosis. There are several uncertainties about paediatric PCC. So far, available literature suggest that 1-3% of recognized children with Severe Acute Respiratory Syndrome COronaVirus 2 (SARS-CoV-2) infection may develop PCC. Its pathogenesis is unknown, although there is increasing evidence about possible abnormalities in the immune responses, cellular metabolism and intestinal microbiota, along with chronic endothelitis.

SUMMARY

Management of PCC in children is complex and require a multidisciplinary approach, with the goal of offering the best care possible to support diagnostics, research, mental health and access to research projects.

Risk Factors for Persistent Anosmia and Dysgeusia in Children with SARS-CoV-2 Infection: A Retrospective Study

BACKGROUND

Olfactory and gustative dysfunctions are two of the most common post-acute sequelae of SARS-CoV-2 infection in children, which can have a negative impact on the routines of children and families. As several children have had COVID-19 since the Omicron variant, it is important to investigate if this increase in infections is reflected in higher olfactory/taste disfunctions. The primary aim of this study was to characterize the presence of olfactory/gustative problems in a cohort of children, its evolution, and its association with risk factors such as COVID-19 variant, hospitalization, presence of olfactory/gustative dysfunction during the acute phase, and vaccination.

METHODS

This was a retrospective analysis of children with microbiologically confirmed SARS-CoV-2 infection evaluated in person at a referral pediatric post-COVID-19 clinic in Rome, Italy. We included children younger than 19 years old, evaluated from the beginning of the pandemic up to October 2022. At specific timepoints, we investigated the presence of olfactory/taste disfunctions and evaluated them according to the SARS-CoV-2 variants circulating at the time of infection.

RESULTS

A total of 1250 children (650 females; 52.0%) with a mean age of 6.77 (±4.12) years were included in the study. At 3, 6, 12, and 18 months, 12 (9.6%), 7 (5.6%), 2 (1.6%), and 1 (0.8%) of the children reported anosmia and dysgeusia post-COVID-19 infection, respectively. The presence of anosmia and dysgeusia during the acute phase of infection and being infected with a pre-Omicron variant were found to be significant risk factors for persistent olfactory and gustatory dysfunction during all follow-up periods.

CONCLUSIONS

anosmia and dysgeusia symptoms tended to decrease gradually over time, but not all children recovered quickly.

Mental Health and Physical Complaints of German Children and Adolescents before and during the COVID-19 Pandemic: A Repeated Cross-Sectional Study

The potential impact of the COVID-19 pandemic on young people's mental and physical health is of increasing concern. We examined the levels of internalizing and externalizing problem behavior and physical complaints before and during the COVID-19 pandemic in Germany. Data came from a repeated cross-sectional study on child and youth health in schools in Germany. Assessments took place from November to February each year. Two data collections were conducted before the COVID-19 pandemic in 2018-2019 and in 2019-2020. Collections during the pandemic took place in 2020-2021 and 2021-2022. A total of 63,249 data observations were included in the analyses. Multilevel analyses were used to examine temporal trends in mean emotional problems (e.g., often unhappy, downhearted), hyperactivity-inattention (e.g., constantly fidgeting or squirming), conduct problems (e.g., fights with other children), and physical complaints. Models were adjusted for age, gender, school type, socioeconomic status, and sensation seeking. During the COVID-19 pandemic, children and adolescents in Germany experienced an increase in emotional problems from the pre-pandemic cohort 2019-2020 to the pandemic cohort 2021-2022 (β = 0.56, 95% CI (0.51-0.62)) and, over the course of the pandemic, reported elevated levels of physical complaints (β = 0.19, 95% CI (0.16-0.21)). Findings of increased emotional problems and physical complaints after the two years of the pandemic support the ongoing demand for low-threshold health promotion and prevention and the need for further monitoring of young people's health in Germany.

Pulmonary recovery after COVID-19 - a review

INTRODUCTION

COVID-19 is caused by infection with the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). As the respiratory tract is the primary site of infection and host-mediated inflammatory responses, pathologies and dysfunction of the respiratory system characterize the severe disease and are typically associated with the need for oxygen supply or even ventilator support. In survivors of severe COVID-19, computed tomography follow-up frequently reveals structural lung abnormalities, and one-third of individuals who were hospitalized during acute COVID-19 demonstrate persisting lung abnormalities for at least 12 months after disease onset.

AREAS COVERED

This review summarizes current evidence on pulmonary recovery after COVID-19, focusing on adult patients who suffered from COVID-19 pneumonia.

EXPERT OPINION

Severe COVID-19 is associated with a high frequency of persisting lung abnormalities at follow-up. The long-term consequences of these findings remain elusive and urge further evaluation to identify individuals at risk for COVID-19 long-term consequences.

Prevalence of mental health problems among children with long COVID: A systematic review and meta-analysis

INTRODUCTION

The number of children with mental health problems has more than doubled since the COVID-19 pandemic. However, the effect of long Covid on children's mental health is still debatable. Recognising long Covid as a risk factor for mental health problems in children will increase awareness and screening for mental health problems following COVID-19 infection, resulting in earlier intervention and lower morbidity. Therefore, this study aimed to determine the proportion of mental health problems post-COVID-19 infection in children and adolescents, and to compare them with the population with no previous COVID-19 infection.

METHODOLOGY

A systematic search was done in seven databases using pre-defined search terms. Cross-sectional, cohort and interventional studies reporting the proportion of mental health problems among children with long COVID in the English language from 2019 to May 2022 were included. Selection of papers, extraction of data and quality assessment were done independently by two reviewers. Studies with satisfactory quality were included in meta-analysis using R and Revman software programmes.

RESULTS

The initial search retrieved 1848 studies. After screening, 13 studies were included in the quality assessments. Meta-analysis showed children who had previous COVID-19 infection had more than two times higher odds of having anxiety or depression, and 14% higher odds of having appetite problems, compared to children with no previous infection. The pooled prevalence of mental health problems among the population were as follows; anxiety: 9%(95% CI:1, 23), depression: 15%(95% CI:0.4, 47), concentration problems: 6%(95% CI: 3, 11), sleep problems: 9%(95% CI:5, 13), mood swings: 13% (95%CI:5, 23) and appetite loss: 5%(95% CI:1, 13). However, studies were heterogenous and lack data from low- and middle-income countries.

CONCLUSION

Anxiety, depression and appetite problems were significantly increased among post-COVID-19 infected children, compared to those without a previous infection, which may be attributed to long COVID. The findings underscore the importance of screening and early intervention of children post-COVID-19 infection at one month and between three to four months.

Features of COVID-19 in children

The novel SARS-CoV-2 coronavirus infection is predominantly asymptomatic or presenting few symptoms in children, and life-threatening complications are rare. In most cases, symptoms of ARVI are observed, such as fever, cough, myalgia, or weakness, which are milder than in adult patients. In addition, most laboratory and radiographic findings in children with COVID-19 are nonspecific. However, some children may develop prolonged forms of COVID-19, as well as long-term symptoms (post-COVID syndrome) after the illness, which significantly affect the quality of life. There are different data regarding the prevalence and duration of long-term effects of a new coronavirus infection in children. The most common symptoms following COVID-19 in children/teens are fatigue, lack of concentration, and muscle pain. The review presents the latest literature data on the duration and course of COVID-19 in children. It should be remembered that long-term symptoms could affect the physical, social, and psychological well-being of children and adolescents in the future. 

The Prevalence, Characteristics and Risk Factors of Persistent Symptoms in Non-Hospitalized and Hospitalized Children with SARS-CoV-2 Infection Followed-Up for up to 12 Months: A Prospective, Cohort Study in Rome, Italy

Previous studies assessing the prevalence of COVID-19 sequelae in children have included either a small number of children or a short follow-up period, or have only focused on hospitalized children. We investigated the prevalence of persistent symptoms amongst children and assessed the risk factors, including the impact of variants. A prospective cohort study included children (≤18 years old) with PCR-confirmed SARS-CoV-2 infection. The participants were assessed via telephone and face-to-face visits at 1-5, 6-9 and 12 or more months post-SARS-CoV-2 diagnosis using the ISARIC COVID-19 follow-up survey. Of the 679 children enrolled, 51% were female; 488 were infected during the wild virus wave, and 29 were infected with the Alpha, 42 with the Delta and 120 with the Omicron variants. Fatigue (19%), headache (12%), insomnia (7.5%), muscle pain (6.9%) and confusion with concentration issues (6.8%) were the most common persistent symptoms. Families reported an overall improvement over time, with 0.7% of parents interviewed at 12 months or more of the follow-up period reporting a poor recovery. Patients that had not recovered by 6-9 months had a lower probability of recovering during the next follow-up period. Children infected with a variant or the wild virus had an overall similar rate of persistent symptoms (although the pattern of reported symptoms differed significantly) and recovery rates. Conclusions: Recovery rates after SARS-CoV-2 infection improved as time passed from the initial infection, ranging from 4% of children having poor recovery at 1-5 months' follow-up to 1.3% at 6-9 months and 0.7% at 12 months. The patterns of persistence changed according to the variants involved at the time of infection. This study reinforces that a subgroup of children develop long-lasting persistent symptoms and highlights the need for further studies investigating the reasons behind the development of PCC.

Mental Fatigue, Activities of Daily Living, Sick Leave and Functional Status among Patients with Long COVID: A Cross-Sectional Study

Studies suggest that persistent symptoms after COVID-19 (long COVID) influence functioning and activities of daily living (ADL). However, it is still uncertain how and to what extent. This study aimed to describe patient-reported mental fatigue, ADL problems, ADL ability, sick leave and functional status among patients with long COVID. In this cross-sectional study, 448 patients, ≥18 years old and referred to occupational therapy at a Danish Post-COVID-19 Clinic, were included. Mental fatigue was measured by the Mental Fatigue Scale, ADL problems and ability were measured by the Canadian Occupational Performance Measure, sick leave was self-reported and functional status was evaluated by the Post-COVID-19 Functional Status Scale. Mean age was 46.8 years, 73% of the patients were female, and 75% suffered from moderate to severe mental fatigue. The majority reported difficulties performing productive and leisure activities. The median performance and satisfaction scores were 4.8 and 3, respectively. In total, 56% of the patients were on sick leave, and 94% were referred to rehabilitation. A decrease in functional status was found between pre-COVID-19 and assessment. Conclusively, the patients were highly affected in their everyday life and had distinct rehabilitation needs. Future research is needed to address causalities and rehabilitation for this patient group.

Water-Based and Land-Based Exercise for Children with Post-COVID-19 Condition (postCOVIDkids)-Protocol for a Randomized Controlled Trial

The most common symptoms of post-COVID-19 condition in children are fatigue, shortness of breath, exercise intolerance, and weakness. The post-COVID-19 condition in children can be very debilitating and lead to prolonged school absences, high morbidity, and limitations in daily functioning. The aim of this research project is to determine the effectiveness of land-based and water-based exercise interventions on exercise capacity, fatigue, health-related quality of life, and pulmonary function in children with post-COVID-19 condition. This study is a prospective randomized controlled study with pre- and post-intervention assessment. Participants will be recruited from Warsaw's primary schools and primary healthcare units according to the inclusion criteria: (i) symptoms of post-COVID-19 condition lasting more than one month following initial COVID-19 infection confirmed by the diagnosis by general practitioner (including obligatory fatigue and shortness of breath/respiratory problems); (ii) age 10-12 years old. Participants meeting the inclusion criteria will be randomized to one of three groups: water-based exercise, land-based exercise, or control (no exercise). We hope this study will provide guidance for long-COVID-19 rehabilitation in children.

Extended coagulation profile of children with Long Covid: a prospective study

Emerging data suggests that endotheliopathy changes can be associated with post covid condition (PCC) in adults. Research on the matter in children is lacking. We analyzed an extended coagulation profile including biomarkers of endothelial damage in children with PCC and compared it with a control group of children that fully recovered post- SARS-CoV-2 infection. A case-control study enrolling children below 18 years of age with previous microbiologically confirmed SARS-CoV-2 infection in a pediatric post-covid unit in Italy ≥ 8 weeks after the initial infection. Samples were taken at 8 and 12 weeks after the SARS-CoV-2 diagnosis and analyzed for coagulation profiling (fibrinogen, prothrombin time, international normalized ratio, activated partial thromboplastin time, d-dimers, factor VIII coagulant activity, plasma von Willebrand factor (VWF) antigen and VWF ristocetin cofactor (RC)). We compared coagulation profiles in samples from children identified with PCC (at least one, or three or more symptoms, which could not be explained by an alternative diagnosis, at the 8- and 12-week follow-up assessment using the pediatric Long Covid International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) survey. Seventy-five children were enrolled, 49.3% were females, the median age was 10.2 (IQR 4.9) years. Forty-six (61%) of the children had at least one persisting symptom at the eight weeks post-onset, (PCC8); 39/75 (52%) had persistent symptoms for more than 12 weeks (PCC12) and 15/75(32%) had at least three persisting symptoms (PCC ≥ 3) at 12 weeks. Children with PCC presented more frequently with abnormal D-Dimer levels above the reference range compared to children that had fully recovered at the 8-12 weeks (39.1% vs. 17.2%, p = 0.04), and 12 week follow up or more (41% vs. 17.2%, p = 0.05), and in children with three or more symptoms at 12 weeks follow up compared to those that had recovered (64.3% vs. 22.2%, p = 0.002). For the other coagulation profiles, there were abnormal values detected for VWF, FVIII, RC and Fibrinogen but no significant differences between children with PCC compared to controls. Although the majority of children in our cohort showed coagulation profile within or close to normal ranges, we found that a higher proportion of children with PCC, and specifically those with a more severe spectrum characterized with three or more persisting symptoms, had abnormal D-dimer levels compared to other children that fully recovered from an acute SARS-CoV-2 infection.

Lactoferrin as Possible Treatment for Chronic Gastrointestinal Symptoms in Children with Long COVID: Case Series and Literature Review

Long COVID is an emergent, heterogeneous, and multisystemic condition with an increasingly important impact also on the pediatric population. Among long COVID symptoms, patients can experience chronic gastrointestinal symptoms such as abdominal pain, constipation, diarrhea, vomiting, nausea, and dysphagia. Although there is no standard, agreed, and optimal diagnostic approach or treatment of long COVID in children, recently compounds containing multiple micronutrients and lactoferrin have been proposed as a possible treatment strategy, due to the long-standing experience gained from other gastrointestinal conditions. In particular, lactoferrin is a pleiotropic glycoprotein with antioxidant, anti-inflammatory, antithrombotic, and immunomodulatory activities. Moreover, it seems to have several physiological functions to protect the gastrointestinal tract. In this regard, we described the resolution of symptoms after the start of therapy with high doses of oral lactoferrin in two patients referred to our post-COVID pediatric unit due to chronic gastrointestinal symptoms after SARS-CoV-2 infection.

Dysregulation of glutamine/glutamate metabolism in COVID-19 patients: A metabolism study in African population and mini meta-analysis

Coronavirus disease 2019 (COVID-19) remains a serious global threat. The metabolic analysis had been successfully applied in the efforts to uncover the pathological mechanisms and biomarkers of disease severity. Here we performed a quasi-targeted metabolomic analysis on 56 COVID-19 patients from Sierra Leone in western Africa, revealing the metabolomic profiles and the association with disease severity, which was confirmed by the targeted metabolomic analysis of 19 pairs of COVID-19 patients. A meta-analysis was performed on published metabolic data of COVID-19 to verify our findings. Of the 596 identified metabolites, 58 showed significant differences between severe and nonsevere groups. The pathway enrichment of these differential metabolites revealed glutamine and glutamate metabolism as the most significant metabolic pathway (Impact = 0.5; -log10P = 1.959). Further targeted metabolic analysis revealed six metabolites with significant intergroup differences, with glutamine/glutamate ratio significantly associated with severe disease, negatively correlated with 10 clinical parameters and positively correlated with SPO₂ (r_s = 0.442, p = 0.005). Mini meta-analysis indicated elevated glutamate was related to increased risk of COVID-19 infection (pooled odd ratio [OR] = 2.02; 95% confidence interval [CI]: 1.17-3.50) and severe COVID-19 (pooled OR = 2.28; 95% CI: 1.14-4.56). In contrast, elevated glutamine related to decreased risk of infection and severe COVID-19, the pooled OR were 0.30 (95% CI: 0.20-0.44), and 0.44 (95% CI: 0.19-0.98), respectively. Glutamine and glutamate metabolism are associated with COVID-19 severity in multiple populations, which might confer potential therapeutic target of COVID-19, especially for severe patients.

COVID-19 and children

There has been substantial research on adult COVID-19 and how to treat it. But how do severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections afflict children? The COVID-19 pandemic has yielded many surprises, not least that children generally develop less severe disease than older adults, which is unusual for a respiratory disease. However, some children can develop serious complications from COVID-19, such as multisystem inflammatory syndrome in children (MIS-C) and Long Covid, even after mild or asymptomatic COVID-19. Why this occurs in some and not others is an important question. Moreover, when children do contract COVID-19, understanding their role in transmission, especially in schools and at home, is crucial to ensuring effective mitigation measures. Therefore, in addition to nonpharmaceutical interventions, such as improved ventilation, there is a strong case to vaccinate children so as to reduce possible long-term effects from infection and to decrease transmission. But questions remain about whether vaccination might skew immune responses to variants in the long term. As the experts discuss below, more is being learned about these important issues, but much more research is needed to understand the long-term effects of COVID-19 in children.

Chronic Olfactory Dysfunction in Children with Long COVID: A Retrospective Study

Olfactory dysfunction is one of the long-term consequences of acute SARS-CoV-2 infection in adults. This study aims to analyze the prevalence of chronic anosmia among COVID-19 children and to bring to light its impact on their families’ quality of life and wellbeing. Children younger than 18 years old, who were detected as being COVID-19-positive by RT-PCR and were assessed in a pediatric post-COVID outpatient clinic at least 28 days after the onset of the acute infection, were included in the study. The patients suffering from persisting smell disorders were asked to answer a questionnaire about their symptoms and how they influence their daily life. Out of the 784 children evaluated, 13 (1.7%) presented olfactory impairment at a mean follow-up since the acute infection of more than three months. Parents’ answers showed that they were worried about their children’s health, in particular they wanted to know if and when they would recover and if these disorders would have long-term consequences. They also wanted to share their experiences, in order to help other people who are experiencing the same disorders in everyday life. Our study highlights that smell disorders can significantly upset children’s eating habits and everyday activities. Furthermore, these findings suggest that future research should try to better understand the mechanisms causing loss of smell in COVID-19 patients and find the most appropriate treatment.

Long COVID endotheliopathy: hypothesized mechanisms and potential therapeutic approaches

SARS-CoV-2-infected individuals may suffer a multi-organ system disorder known as "long COVID" or post-acute sequelae of SARS-CoV-2 infection (PASC). There are no standard treatments, the pathophysiology is unknown, and incidence varies by clinical phenotype. Acute COVID-19 correlates with biomarkers of systemic inflammation, hypercoagulability, and comorbidities that are less prominent in PASC. Macrovessel thrombosis, a hallmark of acute COVID-19, is less frequent in PASC. Female sex at birth is associated with reduced risk for acute COVID-19 progression, but with increased risk of PASC. Persistent microvascular endotheliopathy associated with cryptic SARS-CoV-2 tissue reservoirs has been implicated in PASC pathology. Autoantibodies, localized inflammation, and reactivation of latent pathogens may also be involved, potentially leading to microvascular thrombosis, as documented in multiple PASC tissues. Diagnostic assays illuminating possible therapeutic targets are discussed.

Recovering or Persisting: The Immunopathological Features of SARS-CoV-2 Infection in Children

Background. The profile of cellular immunological responses of children across the spectrum of COVID-19, ranging from acute SARS-CoV-2 infection to full recovery or Long COVID, has not yet been fully investigated. Methods. We examined and compared cytokines in sera and cell subsets in peripheral blood mononuclear cells (B and regulatory T lymphocytes) collected from four distinct groups of children, distributed as follows: younger than 18 years of age with either acute SARS-CoV-2 infection (n = 49); fully recovered from COVID-19 (n = 32); with persistent symptoms (Long COVID, n = 51); and healthy controls (n = 9). Results. In the later stages after SARS-CoV-2 infection, the cohorts of children, both with recovered and persistent symptoms, showed skewed T and B subsets, with remarkable differences when compared with children at the onset of the infection and with controls. The frequencies of IgD+CD27− naïve B cells, IgD+IgM+ and CD27−IgM+CD38dim B cells were higher in children with recent infection than in those with an older history of disease (p < 0.0001 for all); similarly, the total and natural Tregs compartments were more represented in children at onset when compared with Long COVID (p < 0.0001 and p = 0.0005, respectively). Despite the heterogeneity, partially due to age, sex and infection incidence, the susceptibility of certain children to develop persistent symptoms after infection appeared to be associated with the imbalance of the adaptive immune response. Following up and comparing recovered versus Long COVID patients, we analyzed the role of circulating naïve and switched B and regulatory T lymphocytes in counteracting the evolution of the symptomatology emerged, finding an interesting correlation between the amount and ability to reconstitute the natural Tregs component with the persistence of symptoms (linear regression, p = 0.0026). Conclusions. In this study, we suggest that children affected by Long COVID may have a compromised ability to switch from the innate to the adaptive immune response, as supported by our data showing a contraction of naïve and switched B cell compartment and an unstable balance of regulatory T lymphocytes occurring in these children. However, further prospective immunological studies are needed to better clarify which factors (epigenetic, diet, environment, etc.) are involved in the impairment of the immunological mechanisms in the Long COVID patients.

Long COVID: A proposed hypothesis-driven model of viral persistence for the pathophysiology of the syndrome

Background: Long COVID (coronavirus disease 2019) syndrome includes a group of patients who, after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), exhibit lingering mild-to-moderate symptoms and develop medical complications that can have lasting health problems. In this report, we propose a model for the pathophysiology of the long COVID presentation based on increased proinflammatory cytokine production that results from the persistence of the SARS-CoV-2 virus or one of its molecular components. Associated with this hyperproduction of inflammatory cytokines is a heightened activity of nuclear factor κ B (NF-κB) and p38 mitogen-activated protein kinase signaling pathways that regulate cytokine production. Objective: The purpose of the present report was to review the causes of long COVID syndrome and suggest ways that can provide a basis for a better understanding of the clinical symptomatology for the of improved diagnostic and therapeutic procedures for the condition. Methods: Extensive research was conducted in medical literature data bases by applying terms such as "long COVID" associated with "persistence of the SARS-CoV-2 virus" "spike protein' "COVID-19" and "biologic therapies." Results and Conclusions: In this model of the long COVID syndrome, the persistence of SARS-CoV-2 is hypothesized to trigger a dysregulated immune system with subsequent heightened release of proinflammatory cytokines that lead to chronic low-grade inflammation and multiorgan symptomatology. The condition seems to have a genetic basis, which predisposes individuals to have a diminished immunologic capacity to completely clear the virus, with residual parts of the virus persisting. This persistence of virus and resultant hyperproduction of proinflammatory cytokines are proposed to form the basis of the syndrome.

Clinical characteristics, activity levels and mental health problems in children with long coronavirus disease: a survey of 510 children

Background: Whether long coronavirus disease pertains to children as well is not yet clear. Methods: The authors performed a survey in children suffering from persistent symptoms since initial infection. A total of 510 children infected between January 2020 and January 2021 were included. Results: Symptoms such as fatigue, headache, muscle and joint pain, rashes and heart palpitations and issues such as lack of concentration and short-term memory problems were particularly frequent and confirm previous observations, suggesting that they may characterize this condition. Conclusion: A better comprehension of long coronavirus disease is urgently needed.