Data-driven identification of SARS-CoV-2 subpopulations using PhenoGraph and binary-coded genomic data.

For epidemic prevention and control, the identification of SARS-CoV-2 subpopulations sharing similar micro-epidemiological patterns and evolutionary histories is necessary for a more targeted investigation into the links among COVID-19 outbreaks caused by SARS-CoV-2 with similar genetic backgrounds. Genomic sequencing analysis has demonstrated the ability to uncover viral genetic diversity. However, an objective analysis is necessary for the identification of SARS-CoV-2 subpopulations. Herein, we detected all the mutations in 186 682 SARS-CoV-2 isolates. We found that the GC content of the SARS-CoV-2 genome had evolved to be lower, which may be conducive to viral spread, and the frameshift mutation was rare in the global population. Next, we encoded the genomic mutations in binary form and used an unsupervised learning classifier, namely PhenoGraph, to classify this information. Consequently, PhenoGraph successfully identified 303 SARS-CoV-2 subpopulations, and we found that the PhenoGraph classification was consistent with, but more detailed and precise than the known GISAID clades (S, L, V, G, GH, GR, GV and O). By the change trend analysis, we found that the growth rate of SARS-CoV-2 diversity has slowed down significantly. We also analyzed the temporal, spatial and phylogenetic relationships among the subpopulations and revealed the evolutionary trajectory of SARS-CoV-2 to a certain extent. Hence, our results provide a better understanding of the patterns and trends in the genomic evolution and epidemiology of SARS-CoV-2.

Operational considerations for peritoneal dialysis management during the COVID-19 pandemic.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is an infectious respiratory disease caused by a novel coronavirus-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It is spread from human to human and has resulted in a global pandemic, posing a disastrous public health risk worldwide. Patients with chronic kidney disease, especially those on dialysis, are considered to be at higher risk of developing severe COVID-19 due to their immunocompromised status and frail condition. The home treatment setting of peritoneal dialysis (PD) has advantages in terms of implementing self-care when routine hospital visits and social activities are restricted, thus greatly reducing exposure of PD patients to the virus. METHODS AND RESULTS: We outline general operational considerations in PD management during the COVID-19 pandemic, including precautionary measures for PD patients and healthcare staff. Precautionary measures for PD patients include education on prevention of, and screening for, COVID-19, preclinic screening, in-clinic management, meticulous remote patient management and special hospitalization arrangements. The diagnosis and treatment of PD patients with COVID-19 are discussed. Precautionary measures for PD staff include continuous education on, and training in, COVID-19, exposure history surveillance and self-monitoring for COVID-19 among healthcare personnel, appropriate personal protective equipment and hand hygiene, organization of medical activities and staffing, and adequate environment cleaning. CONCLUSIONS: This is a battle of the entire human society against the novel coronavirus. Integrated teamwork among healthcare providers, supported by society as a whole, is needed as part of the ongoing public health response to try to slow the spread of COVID-19.