SARS-CoV-2 Evolution among Oncological Population: In-Depth Virological Analysis of a Clinical Cohort

Background: Oncological patients have a higher risk of prolonged SARS-CoV-2 shedding, which, in turn, can lead to evolutionary mutations and emergence of novel viral variants. The aim of this study was to analyze biological samples of a cohort of oncological patients by deep sequencing to detect any significant viral mutations. Methods: High-throughput sequencing was performed on selected samples from a SARS-CoV-2-positive oncological patient cohort. Analysis of variants and minority variants was performed using a validated bioinformatics pipeline. Results: Among 54 oncological patients, we analyzed 12 samples of 6 patients, either serial nasopharyngeal swab samples or samples from the upper and lower respiratory tracts, by high-throughput sequencing. We identified amino acid changes D614G and P4715L as well as mutations at nucleotide positions 241 and 3037 in all samples. There were no other significant mutations, but we observed intra-host evolution in some minority variants, mainly in the ORF1ab gene. There was no significant mutation identified in the spike region and no minority variants common to several hosts. Conclusions: There was no major and rapid evolution of viral strains in this oncological patient cohort, but there was minority variant evolution, reflecting a dynamic pattern of quasi-species replication.</p

Factors associated with coinfections in invasive aspergillosis: a retrospective cohort study

Objectives: To describe the coinfections in invasive aspergillosis (IA), to identify factors associated with coinfections, and to evaluate the impact of coinfection on mortality.Patients and methods: We conducted a monocentric retrospective study of consecutive putative, probable, or proven IA that occurred between 1997 and 2017. All coinfections, with an onset within 7 days before or after the first sign of aspergillosis, were identified. Factors associated with coinfections and mortality were analysed by multivariable analysis.Results: Among the 690 patients with IA included in the study, the median age was 57 years (range 7 days to 90 years). A coinfection was diagnosed in 272/690 patients (39.4%, 95%CI 35.8-43.2). The location of this coinfection was pulmonary only in 131/272 patients (48%), bloodstream only in 66/272 patients (24%) and other/multiple sites in 75/272 patients (28%). Coinfections were bacterial (110/272 patients, 40%), viral (58/272, 21%), fungal (57/272, 21%), parasitic (5/272, 2%) or due to multiple types of pathogens (42/272, 15%). Factors associated with a coinfection in adjusted analysis were: allogeneic haematopoietic stem-cell transplantation (OR 2.3 (1.2-4.4)), other haematological malignancies (OR 2.1 (1.2-3.8)), other underlying diseases (OR 4.3 (1.4-13.6)), lymphopenia (OR 1.7 (1.1-2.5)), C-reactive protein >180 mg/L (OR 1.9 (1.2-3.0)), fever (OR 2.4 (1.5-4.1)), tracheal intubation (OR 2.6 (1.5-4.7)), isolation of two or more different Aspergillus species (OR 2.7 (1.1-6.3)), and the presence of non-nodular lesions on chest computed tomography (OR 2.2 (1.3-3.7) and OR 2.2 (1.2-4.0)). Coinfections were independently associated with a higher mortality at week 12 (adjusted HR 1.5 (1.1-1.9), p < 0.01).Conclusions: Coinfections are frequent in IA patients and are associated with higher mortality