Comparison of Humoral Response between Third and Fourth Doses of COVID-19 Vaccine in Hemodialysis Patients.

Dialysis patients are more likely to die or become hospitalized from coronavirus disease 2019 (COVID-19). Currently, only a few studies have evaluated the efficacy of a fourth booster vaccination in hemodialysis (HD) patients and there is not enough evidence to recommend for or against a fourth booster vaccination. This study compared the humoral response and disease severity of patients on HD who received either three or four doses of COVID-19 vaccine.

Humoral Immune Response of Heterologous ChAdOx1 nCoV-19 and mRNA-1273 Prime-Boost Vaccination against SARS-CoV-2 Variants in Korea.

The immunogenicity of a heterologous vaccination regimen consisting of ChAdOx1 nCoV-19 (a chimpanzee adenovirus-vectored vaccine) followed by mRNA-1273 (a lipid-nanoparticle-encapsulated mRNA-based vaccine) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), specifically the omicron variant (B.1.1.

Seroprevalence of SARS-CoV-2 antibodies during the third wave of COVID-19 in the Seoul metropolitan area of Korea.

Objectives: After the third wave of coronavirus disease 2019 (COVID-19), by mid-February 2021, approximately 0.16% of the Korean population was confirmed positive, which appeared to be among the lowest rates worldwide at that time. However, asymptomatic transmission is challenging for COVID-19 surveillance.

Seroprevalence of SARS-CoV-2 antibodies in the community based on participants in the 2020 Korea National Health and Nutrition Examination Survey.

Objectives: The Korea National Health and Nutrition Examination Survey (KNHANES) is a nationwide cross-sectional surveillance system that assesses the health and nutritional status of the Korean population. To evaluate the occurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the community, we investigated the prevalence of anti-SARS-CoV-2 antibodies in the sera of KNHANES participants.

Methods: Subjects were recruited between April 24 and December 12, 2020.

Performance Comparison of Five SARS-CoV-2 Antibody Assays for Seroprevalence Studies.

Background: Seroprevalence studies of coronavirus disease 2019 (COVID-19) cases, including asymptomatic and past infections, are important to estimate the scale of the disease outbreak and to establish quarantine measures. We evaluated the clinical performance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody assays available in Korea for use in seroprevalence studies.

Methods: The sensitivity, specificity, cross-reactivity, and interference of five SARS-CoV-2 antibody assays were evaluated using the following: 398 serum samples from confirmed COVID-19 patients, 510 negative control samples from before 2018 (pre-pandemic), 163 serum samples from patients with SARS, Middle East respiratory syndrome (MERS), and other viral infections, and five samples for the interference study.

Historical control data from 13-week repeated toxicity studies in Crj:CD (SD) rats.

Reference ranges of standard experimental parameters are useful for comparisons in toxicology. The aim of this study was to collect data from 13-week repeated toxicity studies in Crl:CD (SD) rats, a strain widely used for toxicity and efficacy research, for establishing domestic reference values. Data on body weight, food consumption; urinalysis, hematological, and blood biochemical parameters; and organ weights were collected from 11 toxicity studies in 220 Crl:CD (SD) rats (110 males and 110 females).