Long COVID in children

Treatment of Acute COVID-19 and COVID-19 Exposures in Children and Adolescents

ABSTRACT

The landscape of acute COVID-19 therapeutics has dramatically evolved since the onset of the pandemic. The treatment of acute COVID-19 in children and adolescents requires knowledge of risk factors and clinical features to appropriately select antiviral and immunomodulatory therapies. This review article provides updated guidance for emergency physicians in the treatment of acute COVID-19 in children and adolescents.

Mental health effects of the COVID-19 pandemic on children and young adults: empirical analysis of the past, present and the way forward

The SARS-CoV-2 virus and its variants have had and are having serious implications for the mental health of the public. The critical limitations in the published literature for children, adolescents and young adults raise doubts about their clinical utility and overall generalisability. Amidst these gaps in knowledge, a twin study (Rimfeld et al) addresses several of these issues in relation to heritable individual differences and responses to environmental stressors. Besides calculating genetic correlation, the longitudinal study also compares symptoms at four different time points during the pandemic. These findings reflect a counterintuitive understanding of the role of resilience in the mental health of young adults in the UK. Unlike prior studies, this study focuses on methodological designs and underscores the applications of accurate statistical measures in observing these complex phenomena.

A Methodological Framework for Assessing the Benefit of SARS-CoV-2 Vaccination following Previous Infection: Case Study of Five- to Eleven-Year-Olds

Vaccination rates against SARS-CoV-2 in children aged five to eleven years remain low in many countries. The current benefit of vaccination in this age group has been questioned given that the large majority of children have now experienced at least one SARS-CoV-2 infection. However, protection from infection, vaccination or both wanes over time. National decisions on offering vaccines to this age group have tended to be made without considering time since infection. There is an urgent need to evaluate the additional benefits of vaccination in previously infected children and under what circumstances those benefits accrue. We present a novel methodological framework for estimating the potential benefits of COVID-19 vaccination in previously infected children aged five to eleven, accounting for waning. We apply this framework to the UK context and for two adverse outcomes: hospitalisation related to SARS-CoV-2 infection and Long Covid. We show that the most important drivers of benefit are: the degree of protection provided by previous infection; the protection provided by vaccination; the time since previous infection; and future attack rates. Vaccination can be very beneficial for previously infected children if future attack rates are high and several months have elapsed since the previous major wave in this group. Benefits are generally larger for Long Covid than hospitalisation, because Long Covid is both more common than hospitalisation and previous infection offers less protection against it. Our framework provides a structure for policy makers to explore the additional benefit of vaccination across a range of adverse outcomes and different parameter assumptions. It can be easily updated as new evidence emerges.

Monoclonal antibodies for prophylaxis and therapy of respiratory syncytial virus, SARS-CoV-2, human immunodeficiency virus, rabies and bacterial infections: an update from the World Association of Infectious Diseases and Immunological Disorders and the Italian Society of Antinfective Therapy

Monoclonal antibodies (mABs) are safe and effective proteins produced in laboratory that may be used to target a single epitope of a highly conserved protein of a virus or a bacterial pathogen. For this purpose, the epitope is selected among those that play the major role as targets for prevention of infection or tissue damage. In this paper, characteristics of the most important mABs that have been licensed and used or are in advanced stages of development for use in prophylaxis and therapy of infectious diseases are discussed. We showed that a great number of mABs effective against virus or bacterial infections have been developed, although only in a small number of cases these are licensed for use in clinical practice and have reached the market. Although some examples of therapeutic efficacy have been shown, not unlike more traditional antiviral or antibacterial treatments, their efficacy is significantly greater in prophylaxis or early post-exposure treatment. Although in many cases the use of vaccines is more effective and cost-effective than that of mABs, for many infectious diseases no vaccines have yet been developed and licensed. Furthermore, in emergency situations, like in epidemics or pandemics, the availability of mABs can be an attractive adjunct to our armament to reduce the impact. Finally, the availability of mABs against bacteria can be an important alternative, when multidrug-resistant strains are involved.

Seroprevalence of immunoglobulin G antibodies against SARS-CoV-2 in children and adolescents in Delhi, India, from January to October 2021: a repeated cross-sectional analysis

Objectives: The aim of this study was to assess changes in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) seroprevalence among children and adolescents in Delhi, India from January 2021 to October 2021Methods: This was a repeated cross-sectional analysis of participants aged 5 to 17 years from 2 SARS-CoV-2 seroprevalence surveys conducted in Delhi, India during January 2021 and September to October 2021. Anti-SARS-CoV-2 IgG antibodies were detected by using the VITROS assay (90% sensitivity, 100% specificity).Results: The seroprevalence among 5- to 17-year-old school-age children and adolescents increased from 52.8% (95% confidence interval [CI], 51.3%−54.3%) in January 2021 to 81.8% (95% CI, 80.9%−82.6%) in September to October 2021. The assay-adjusted seroprevalence was 90.8% (95% CI, 89.8%−91.7%). Seropositivity positively correlated with participants’ age (p<0.001), but not sex (p=0.388). A signal to cut-off ratio ≥4.00, correlating with the presence of neutralization antibodies, was observed in 4,814 (57.9%) participants.Conclusion: The high percentage of seroconversion among children and adolescents indicates the presence of natural infection-induced immunity from past exposure to the SARS-CoV-2 virus. However, the lack of hybrid immunity and the concomitant likelihood of lower levels of neutralization antibodies than in adults due to the absence of vaccination warrants careful monitoring and surveillance of infection risk and disease severity from newer and emergent variants.

A central role for amyloid fibrin microclots in long COVID/PASC: origins and therapeutic implications

Post-acute sequelae of COVID (PASC), usually referred to as 'Long COVID' (a phenotype of COVID-19), is a relatively frequent consequence of SARS-CoV-2 infection, in which symptoms such as breathlessness, fatigue, 'brain fog', tissue damage, inflammation, and coagulopathies (dysfunctions of the blood coagulation system) persist long after the initial infection. It bears similarities to other post-viral syndromes, and to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Many regulatory health bodies still do not recognize this syndrome as a separate disease entity, and refer to it under the broad terminology of 'COVID', although its demographics are quite different from those of acute COVID-19. A few years ago, we discovered that fibrinogen in blood can clot into an anomalous 'amyloid' form of fibrin that (like other β-rich amyloids and prions) is relatively resistant to proteolysis (fibrinolysis). The result, as is strongly manifested in platelet-poor plasma (PPP) of individuals with Long COVID, is extensive fibrin amyloid microclots that can persist, can entrap other proteins, and that may lead to the production of various autoantibodies. These microclots are more-or-less easily measured in PPP with the stain thioflavin T and a simple fluorescence microscope. Although the symptoms of Long COVID are multifarious, we here argue that the ability of these fibrin amyloid microclots (fibrinaloids) to block up capillaries, and thus to limit the passage of red blood cells and hence O2 exchange, can actually underpin the majority of these symptoms. Consistent with this, in a preliminary report, it has been shown that suitable and closely monitored 'triple' anticoagulant therapy that leads to the removal of the microclots also removes the other symptoms. Fibrin amyloid microclots represent a novel and potentially important target for both the understanding and treatment of Long COVID and related disorders.