False-positive SARS-CoV-2 serology in 3 children with Kawasaki disease
DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE
Authors: To, Kelvin K. W.; Chua, Gilbert T.; Kwok, Ka Li; Wong, Joshua S. C.; Au, Dennis Chi Yu; Lam, Yuen Yu; Wong, Wilfred H. S.; Ho, Marco H. K.; Chan, Godfrey C. F.; Chui, Celine S. L.; Li, Xue; Tung, Keith T. S.; Wong, Rosa S.; Tso, Winnie W. Y.; Wong, Ian C. K.; Wong, Christina S. M.; Fong, Carol H. Y.; Chan, Kwok Hung; Yuen, Kwok Yung; Ip, Patrick; Kwan, Mike Y. W.
Abstract
Background: Kawasaki disease (KD) is an acute febrile and eruptive disease with systemic vasculitis predominantly affecting young East Asian children. Recent reports showed that children with KD-like disease from KD low prevalence regions had positive SARS-CoV-2 serology despite a negative SARS-CoV-2 polymerase chain reaction (PCR) in respiratory samples. Objectives: To describe 3 pediatric Kawasaki Disease patients with false positive SARS-CoV-2 serology. Study design: We retrospectively recruited children with KD diagnosed during the COVID-19 outbreak in Hong Kong. Clinical characteristics and laboratory test results including SARS-CoV-2 PCR results were retrieved. We performed a microparticle-based immunoassay for the detection of IgG against nucleoprotein (NP) and spike protein receptor binding domain (RBD), and a microneutralization assay for the detection of neutralizing antibodies. Results: Three Chinese children with typical KD were identified. They had no epidemiological links with COVID-19 patients and tested negative for SARS-CoV-2 NPA PCR. Theywere treated with IVIG and aspirin, and were discharged without complications. Subsequently 2 of them were tested positive against anti-RBD and anti-NP antibodies and 1 was tested positive against anti- RBD antibodies. However, microneutralization assay showed that neutralizing antibodies were absent, suggesting a false-positive IgG result. Conclusion: Detection of neutralizing antibodies is recommended to confirm previous SARS-CoV-2 infection in IgGpositive but PCR-negative patients. (C) 2020 The Author(s). Published by Elsevier Inc.
Nanotechnology Responses to COVID-19
ADVANCED HEALTHCARE MATERIALS
Authors: Ruiz-Hitzky, Eduardo; Darder, Margarita; Wicklein, Bernd; Ruiz-Garcia, Cristina; Martin-Sampedro, Raquel; del Real, Gustavo; Aranda, Pilar
Abstract
Researchers, engineers, and medical doctors are made aware of the severity of the COVID-19 infection and act quickly against the coronavirus SARS-CoV-2 using a large variety of tools. In this review, a panoply of nanoscience and nanotechnology approaches show how these disciplines can help the medical, technical, and scientific communities to fight the pandemic, highlighting the development of nanomaterials for detection, sanitation, therapies, and vaccines. SARS-CoV-2, which can be regarded as a functional core-shell nanoparticle (NP), can interact with diverse materials in its vicinity and remains attached for variable times while preserving its bioactivity. These studies are critical for the appropriate use of controlled disinfection systems. Other nanotechnological approaches are also decisive for the development of improved novel testing and diagnosis kits of coronavirus that are urgently required. Therapeutics are based on nanotechnology strategies as well and focus on antiviral drug design and on new nanoarchitectured vaccines. A brief overview on patented work is presented that emphasizes nanotechnology applied to coronaviruses. Finally, some comments are made on patents of the initial technological responses to COVID-19 that have already been put in practice.