Distinct clinical and immunological profiles of patients with evidence of SARS-CoV-2 infection in sub-Saharan Africa

Abstract

Although the COVID-19 pandemic has left no country untouched there has been limited research to understand clinical and immunological responses in African populations. Here we characterise patients hospitalised with suspected (PCR-negative/IgG-positive) or confirmed (PCR-positive) COVID-19, and healthy community controls (PCR-negative/IgG-negative). PCR-positive COVID-19 participants were more likely to receive dexamethasone and a beta-lactam antibiotic, and survive to hospital discharge than PCR-negative/IgG-positive and PCR-negative/IgG-negative participants. PCR-negative/IgG-positive participants exhibited a nasal and systemic cytokine signature analogous to PCR-positive COVID-19 participants, predominated by chemokines and neutrophils and distinct from PCR-negative/IgG-negative participants. PCR-negative/IgG-positive participants had increased propensity for Staphylococcus aureus and Streptococcus pneumoniae colonisation. PCR-negative/IgG-positive individuals with high COVID-19 clinical suspicion had inflammatory profiles analogous to PCR-confirmed disease and potentially represent a target population for COVID-19 treatment strategies.

Early Th2 inflammation in the upper respiratory mucosa as a predictor of severe COVID-19 and modulation by early treatment with inhaled corticosteroids: a mechanistic analysis

“…Furthermore, mediators such as VEGF were found to be lower in the respiratory tract in early disease as previously found in severe COVID-19. 19 Examination of the mediator temporal relationship showed that there was often a biphasic peak of inflammatory mediators, which is staggered and persists over time. Importantly, however, we found that in patients given inhaled budesonide, the inflammatory peak was attenuated for TNF-α, GM-CSF, and CCL5, and promoted for IFN-γ.…”

“…Immunoassays of mediators were selected to represent putative mechanistic inflammatory pathways associated with respiratory virus infections, and thus COVID-19, 15 , 16 , 17 and were quantified using MSD (Meso Scale Diagnostics, Rockville, MD, USA). All values at or below the lower limit of detection (LLOD) or above the upper limit of detection (ULOD) were replaced by the LLOD or ULOD value as suggested by the assay parameters and are shown in the appendix (p 16) .…”

A comparison of four epidemic waves of COVID-19 in Malawi; an observational cohort study

“…Respiratory samples (combined nasopharyngeal and oropharyngeal swab) and peripheral blood samples were collected at the point of patient recruitment. SARS-CoV-2 PCR diagnostic testing was carried out as previously described (4). For this study, only patients with a positive SARS-CoV-2 PCR test were included.…”

“…At Queen Elizabeth Central Hospital (QECH), Blantyre, patients have been enrolled under the ISARIC Tier 1 protocol since April 2020 (4). We previously demonstrated that, in the first wave of infection, patients admitted to hospital with suspected COVID-19 who were PCR negative, but IgG positive for SARS-CoV-2 had analogous immunological profiles to those who were PCR positive.…”

IL-36 receptor agonist and antagonist imbalance drives neutrophilic inflammation in COPD

“…Nasosorption was performed using Nasosorption™ FX•I device (Hunt Developments UK Ltd) as described by others (61)(62)(63)(64).Briefly, a Nasosorption™ FX•I device containing a synthetic absorptive matrix (SAM) was inserted into each nostril for 60 seconds for sample collection. Each SAM was detached and placed into 300 µl of elution buffer and vortexed for 30 seconds and transferred to a Costar SPIN-X bucket (Sigma Millipore).…”