Following emergence of the SARS-CoV-2 variant Omicron in November 2021, the dominant BA.1 sub-lineage was replaced by the BA.2 sub-lineage in Denmark. We analysed the first 2,623 BA.2 cases from 29 November 2021 to 2 January 2022. No epidemiological or clinical differences were found between individuals infected with BA.1 versus BA.2. Phylogenetic analyses showed a geographic east-to-west transmission of BA.2 from the Capital Region with clusters expanding after the Christmas holidays. Mutational analysis shows distinct differences between BA.1 and BA.2.

Background: Sepsis is a common and often fatal disease. Because sepsis can be caused by many different organisms, biomarkers that can aid in diagnosing sepsis and monitoring treatment efficacy are highly warranted. New sepsis markers may provide additional information to complement the currently used markers. Methods: We used a combination of in-house and commercially available multiplex immunoassays based on Luminex ® xMAP technology to assay biomarkers of potential interest in EDTA-plasma samples. Results: A 3-plex assay for soluble urokinase plasminogen activator receptor (suPAR), soluble triggering receptor expressed on myeloid cells-1 (sTREM-1), and macrophage migration inhibiting factor (MIF) was developed and validated in-house. This 3-plex assay was added to a commercially available interleukin-1␤ (IL-1␤), IL-6, IL-8, granulocyte/macrophage colony-stimulating factor, and tumor necrosis factor-␣ human cytokine panel. No cross-reactivity was observed when the assays were combined. Correlation between values obtained with the 8-plex, the 5-cytokine panel, the 3 in-house 1-plex assays, and a suPAR ELISA ranged from 0.86 to 0.99. Mean within-and between-run CVs were 8.0% and 11%, respectively. Recoveries of suPAR, sTREM-1, and MIF calibrators were 108%, 88%, and 51%, respectively. In plasma collected from 10 patients with bacterial sepsis confirmed by blood culture, the assay detected significantly increased concentrations of all 8 analytes compared with healthy controls.

New lineages of SARS-CoV-2 are of potential concern due to higher transmissibility, risk of severe outcomes, and/or escape from neutralizing antibodies. Lineage B.1.1.7 (the Alpha variant) became dominant in early 2021, but the association between transmissibility and risk factors, such as age of primary case and viral load remains poorly understood. Here, we used comprehensive administrative data from Denmark, comprising the full population (January 11 to February 7, 2021), to estimate household transmissibility. This study included 5,241 households with primary cases; 808 were infected with lineage B.1.1.7 and 4,433 with other lineages. Here, we report an attack rate of 38% in households with a primary case infected with B.1.1.7 and 27% in households with other lineages. Primary cases infected with B.1.1.7 had an increased transmissibility of 1.5–1.7 times that of primary cases infected with other lineages. The increased transmissibility of B.1.1.7 was multiplicative across age and viral load.