COVID‐19 seroprevalence and clinical picture in Swedish pediatric oncology and hematology patients

Abstract

Background: Children develop symptomatic coronavirus disease 2019 more rarely than adults upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pediatric oncology and hematology patients may be at increased risk of severe COVID-19 due to their underlying disease or treatment. We investigated COVID-19 and seroprevalence of anti-SARS-CoV-2 antibodies, respectively, in a Swedish cohort of pediatric oncology and hematology patients.

Children treated against lymphoid malignancies display diminished IFN-gamma producing T cells after polyclonal and Varicella zoster virus peptide activation

“…This study was part of a prospective, single-centre longitudinal cohort study with the primary aim to examine adaptive immune responses to COVID-19 in children between 0 and 18 years of age with cancer 15 . The current study addresses the secondary aim; to investigate memory responses to previously encountered pathogens in immunosuppressed children.…”

“…Clinical characteristics, such as age, gender, diagnosis, immunosuppressive treatment and previous allo-HSCT, were retrieved from electronic patient charts. A more detailed description of the cohort can be found in Sundberg et al 15 . Of the total 151 recruited patients, 103 had available blood samples for this sub-study and 62 of these had su cient peripheral-blood mononuclear cells (PBMCs ≥ 4 million), required for the immunological analyses.…”

Comparison of SARS-CoV-2 seroconversion in children with chronic diseases with healthy children and adults during the first waves of the COVID-19 pandemic

“…The majority of studies involving pediatric patients concern retrospective studies or have assessed the prevalence of infection on registry or survey data (5). These reports have suggested a relatively benign disease course of SARS-CoV-2 infection despite the presence of additional risk factors such as primary or secondary immunodeficiency in children (7)(8)(9)(10)(11)(12). However, these cohorts of patients were assessed mostly in the very early stages of the pandemic, which explains the low seroprevalence noted (7), or these studies were relatively small in terms of sample size and recruited patients with single underlying diseases (10)(11)(12).…”

“…These reports have suggested a relatively benign disease course of SARS-CoV-2 infection despite the presence of additional risk factors such as primary or secondary immunodeficiency in children (7)(8)(9)(10)(11)(12). However, these cohorts of patients were assessed mostly in the very early stages of the pandemic, which explains the low seroprevalence noted (7), or these studies were relatively small in terms of sample size and recruited patients with single underlying diseases (10)(11)(12). In addition, most studies had cross-sectional designs and did not evaluate antibody response over time (7)(8)(9)(10)(11)(12).…”

“…However, these cohorts of patients were assessed mostly in the very early stages of the pandemic, which explains the low seroprevalence noted (7), or these studies were relatively small in terms of sample size and recruited patients with single underlying diseases (10)(11)(12). In addition, most studies had cross-sectional designs and did not evaluate antibody response over time (7)(8)(9)(10)(11)(12). Pediatric seroprevalence studies, specifically those with a prospective or longitudinal design, remained limited to date, mainly because of the lack of access to patient data and blood samples (5,6).…”