The prevalence of long-COVID in children and adolescents

By Shanet Susan AlexReviewed by Danielle Ellis, B.Sc.Jun 27 2022

A recent study published in the Scientific Reports journal assessed the incidence of long-coronavirus disease (COVID) among adolescents and children.

Background

The acute stage of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was the primary focus of healthcare up until this point. Nevertheless, many people develop incapacitating COVID 2019 (COVID-19) symptoms months after, necessitating additional medical care and follow-up.

Severe SARS-CoV-2 infection is less frequent in children relative to adults. Yet, a minimum of two long-term effects accompany COVID-19 in children: long-COVID and multisystem inflammatory syndrome (MIS-C).

The majority of long-COVID research that has been published to date focused primarily on adult populations, and there is little data on the pediatric population. In addition, it is yet unknown to what extent and how frequently children and adolescents may experience long-COVID symptoms. 

Altogether, there is a demand to establish awareness among parents, researchers, and physicians on the conditions after SARS-CoV-2 infection and for the healthcare system to deeply understand the sequelae to offer tailored medical care and treatment for adolescents and children.

About the study

In the current systematic review and meta-analyses, the researchers aimed to determine the long-COVID prevalence in adolescents and children and to delineate the whole spectrum of symptoms following acute SARS-CoV-2 infection.

The team utilized Embase and PubMed to find observational studies published before 10 February 2022 that had at least 30 patients aged zero to 18 and adhere to the National Institute for Healthcare Excellence's (NICE) criteria of long-COVID. The NICE classifies long-COVID as SARS-CoV-2 infection symptoms that are both continuing, i.e., lasting four to 12 weeks, and after COVID-19, i.e., lasting 12 weeks or more.

Random-effects meta-analyses were conducted to calculate the pooled prevalence with a 95% confidence interval (CI) utilizing the MetaXL software. Further, I2 statistics were used to evaluate heterogeneity. The authors followed the Preferred Reporting Items for Systematic Reviewers and Meta-analysis (PRISMA) reporting guideline in this study.

Results

Collectively, the study results showed that the literature search rendered 8373 publications, among which 21 studies satisfied the requirements for inclusion, and a total of 80,071 adolescents and children were included. The authors found that the long-COVID prevalence in adolescents and children was 25.24%. Additionally, the five most prevalent clinical manifestations of long-COVID among the present target population were headache (7.84%), sleep disorders (8.42%), respiratory symptoms (7.62%), fatigue (9.66%), and mood symptoms (16.50%). 

Only 13 symptoms could be studied using meta-analyses of odds ratios (ORs) matching cases and controls. Relative to controls, children with SARS-CoV-2 infection had a greater chance of developing persistent ageusia/anosmia, dyspnea, and fever.

Interestingly, several long-COVID symptoms reported in the current meta-analyses, including dysphagia, orthostatic intolerance, fatigue, mood disorders, sleep disturbances, poor attention, memory loss, and disorientation, were frequently seen in dysautonomia. A malfunction of the parasympathetic and, or sympathetic autonomic nervous system is known as dysautonomia. Nonetheless, whether dysautonomia was directly associated with the SARS-CoV-2 infection, how it interacts with other viruses, or immune-mediated mechanisms such as cytokines, which were well-known inflammatory response mediators, remains unknown.

The team mentioned the protective elements resulting in lesser severity and duration of SARS-CoV-2 infection, and probably also long-COVID in children, consist of few comorbidities, robust innate immune reactions, decreased angiotensin-converting enzyme-2 (ACE2) receptors expression, and active thymic function, leading to reduced depletion and increased presence of T cells. 

Of note, the drawbacks of the analyzed studies include lack of recall, standardized definitions, misclassification, selection, loss of follow-up, nonresponse, and a high degree of heterogeneity.

Conclusions

On the whole, the current meta-analyses provide additional evidence for the need to regularly monitor the effects of long-COVID in children and adolescents and the necessity of including all relevant control cohorts and factors in studies to comprehend the actual burden of pediatric long-COVID.

Long COVID poses a remarkable public health risk. Besides, there are no recommendations for long-COVID diagnosis or treatment. 

The researchers underlined that protective interventions were crucial for preventing long-COVID in children. To assist clinical management strategies, set up rehabilitation initiatives, formulate guidelines, and conduct therapeutic research, it is necessary to comprehend the pathogenesis and symptoms of long-COVID.

The team mentioned that future research must stratify participants by age, considering that the likelihood of COVID-19 severity and duration rises with age. In addition, the assessment of self-reported symptoms could be substantially skewed by age since younger children may not be able to explain their emotional and functional status pertinent to post-COVID appropriately. Hence, there is a need for more research focusing on different age groups.