Abstract:
Background
During the COVID-19 pandemic, concerns emerged that hospital-based care could
increase the risk of SARS-CoV-2 infection among pediatric patients with cancer,
especially in resource-limited settings where the capacity to isolate patients would
be challenging. Yet, infection rates in this population remain poorly documented, and
it is unclear whether prior common human coronavirus (HCoV) exposures influence
SARS-CoV-2 antibody responses. Here, we used serology to estimate SARS-CoV-2
exposure in children with and without cancer from Western Kenya and evaluated
responses to common HCoVs to explore cross-reactivity.
Methods
We performed multiplex antibody profiling to assess SARS-CoV-2 and HCoV-specific
responses in plasma from children with and without cancer sampled between 2014
and 2022. Unsupervised clustering identified participants with elevated SARS-CoV-2
seroreactivity relative to pre-pandemic samples. Seropositivity was further defined
using a multi-antigen approach based on IgG levels to nucleocapsid and receptor-
binding domain antigens to improve specificity. Cross-reactivity and cross-boosting
by common HCoVs were evaluated through correlation analyses and groupwise com-
parisons of antibody levels, respectively. Results
Of 564 children, 474 were healthy (184 pre-pandemic; 290 post-pandemic) and
90 had cancer (16 pre-pandemic; 74 post-pandemic). Post-pandemic, 69% (200)
of healthy controls exhibited elevated SARS-CoV-2 seroreactivity, with 51% (148)
meeting the criteria for seropositivity. Children with cancer showed similar rates of
seroreactivity (67%) and seropositivity (57%) after adjusting for sampling year, with
incidence increasing annually from 2020 to 2022. Pre-pandemic samples exhibited
weak cross-reactivity to HCoV-OC43 which increased following SARS-CoV-2 infec-
tion; however, no significant boosting of HCoV antibodies was observed.
Conclusions
These findings indicate widespread SARS-CoV-2 exposure among children in Western Kenya and provide no evidence that hospitalization heightened infection risk for
pediatric patients with cancer.