Published in PLOS One on 2026-07-10, this study is presented as an attributed evidence briefing. The excerpts below are the original researchers’ words, reproduced under their Creative Commons Attribution licence. Health Signal has selected the abstract and, where needed, opening background paragraphs; the complete methods, results, limitations and references remain in the linked paper.
Original authors: Katarina M. DiLillo, Catherine S. Forconi, Angela Matta, Jeni Melo, Ryan P. McNamara, Ronald Tonui, Festus N’juguna, Juliana A. Otieno, Boaz Odwar, Ann Kinyua, Douglas A. Lauffenburger, Ann M. Moormann
Source: PLOS One • DOI 10.1371/journal.pone.0353284
Read the complete primary study ↗ · Creative Commons Attribution licence
From the researchers
Abstract
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.
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 comparisons of antibody levels, respectively.
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 infection; however, no significant boosting of HCoV antibodies was observed.
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.
Introduction
The COVID-19 pandemic disrupted cancer care globally, with substantial impacts seen in low- and middle-income countries [1,2]. In sub-Saharan Africa, where pediatric cancer survival rates are among the lowest worldwide [3], the pandemic further strained an already fragile healthcare system. Pediatric patients with cancer faced critical delays in care while being treated in hospitals dealing with shortages of diagnostic tests, personal protective equipment, and infrastructure to support physical distancing [4–6]. These suboptimal infection control conditions, combined with the immunocompromised status of patients with cancer, raised concerns about SARS-CoV-2 exposure risk. Yet, infection rates in children with cancer across Africa remain poorly documented.
The paucity of pediatric SARS-CoV-2 infection data is partly due to diagnostic challenges in resource-limited settings, where mild or asymptomatic infections, which are common in children, often go undetected [7,8]. In this context, serological assays have emerged as a critical tool for estimating the true burden of SARS-CoV-2 infection [9,10]. Serosurveys conducted across sub-Saharan Africa have documented widespread infection; however, few studies have included children [11–14], and none have focused on children with cancer.
Reading this evidence
Use the full paper to check the study design, participant selection, comparator and outcome definitions before drawing a practical conclusion. An association does not by itself show cause and effect. A reported performance measure needs its denominator and uncertainty. A finding from a particular facility, sample or time period should retain that scope when it is discussed elsewhere.
This briefing makes the source accessible within the wider hospital systems desk. It does not assess an individual patient or certify a product. When considering relevance to another health system, examine the original authors’ account of context and limitations, then seek local implementation evidence. The related reporting below provides other studies to read alongside this one; it is a topic connection, rather than a claim that their results are directly comparable.
© 2026 Katarina M. DiLillo, Catherine S. Forconi, Angela Matta, Jeni Melo, Ryan P. McNamara, Ronald Tonui, Festus N’juguna, Juliana A. Otieno, Boaz Odwar, Ann Kinyua, Douglas A. Lauffenburger, Ann M. Moormann. Excerpts reproduced under CC BY. Selection, formatting and contextual notes by Health Signal. The researchers are the authors of the source study, not members of Health Signal’s staff.
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