Variants
Immune boosting by B.1.1.529 (Omicron) depends on previous SARS-CoV-2 exposure
// 14.6.2022
The authors found that Omicron infection boosted immune responses to all other variants, but responses to Omicron itself were muted.
Low testing rates limit the ability of genomic surveillance programs to monitor SARS-CoV-2 variants: a mathematical modelling study
Background Genomic surveillance is essential for monitoring the emergence and spread of SARS-CoV-2 variants. SARS-CoV-2 diagnostic testing is the starting point for SARS-CoV-2 genomic sequencing. // 23.5.2022
Variant-specific symptoms of COVID-19 among 1,542,510 people in England
Infection with SARS-CoV-2 virus is associated with a wide range of symptoms. The REal-time Assessment of Community Transmission -1 (REACT-1) study has been monitoring the spread and clinical manifestation of SARS-CoV-2 among random samples of the population in England from 1 May 2020 to 31 March 2022. // 23.5.2022
SARS-CoV-2 Omicron BA.2.12.1, BA.4 and BA.5 subvariants are superior to their predecessors
A recent study posted to the bioRxiv* preprint server demonstrated that the latest severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages evade immunity imparted by the prior subvariants. // 5.5.2022
Continued Emergence and Evolution of Omicron in South Africa: New BA.4 and BA.5 lineages
// 4.5.2022
Omicron sub-lineages BA.4/BA.5 escape BA.1 infection elicited neutralizing immunity
// 29.4.2022
Monitoring of the SARS-CoV-2 Omicron BA.1/BA.2 variant transition in the Swedish population reveals higher viral quantity in BA.2 cases
Throughout the SARS-CoV-2 pandemic, multiple waves of variants of concern have swept across populations, leading to a chain of new and yet more contagious lineages dominating COVID-19 cases. // 27.3.2022
SARS-CoV-2 Omicron triggers cross-reactive neutralization and Fc effector functions in previously vaccinated, but not unvaccinated individuals
// 22.3.2022
Study finds Omicron sublineage BA.2 is less pathogenic in rodent models than prior SARS-CoV-2 variants
Researchers evaluated the pathogenicity and replication potential of SARS-CoV-2 VOC Omicron lineage, BA.2 in immunocompetent mice and hamsters. // 28.2.2022
Omicron BA. 2 reinfections can occur shortly following BA.1 infection
Researchers investigated the probability of Omicron BA.2 reinfections following SARS-CoV-2 Omicron BA.1 initial infection by whole genomic sequencing in the period of dominance of these subvariants in Denmark. // 24.2.2022
High nasopharyngeal viral load in SARS-CoV-2 Omicron-induced infection
In a recent study posted to the Research Square* pre-print server, a team of researchers from Italy and the United States (US) retrospectively reviewed and compared viral load in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron and previous SARS-CoV-2 strain-induced infection. // 23.2.2022
Assessing the transmissibility of SARS-CoV-2 variants of concern
A new study investigated and compared the transmissibility of severe acute respiratory syndrome coronavirus-2 variants of concern. // 22.2.2022
SARS-CoV-2 Omicron variant rapidly takes over Delta viral strain in Norwegian households
Researchers compared the secondary attack rates SARS-CoV-2 Omicron and Delta variants of concern in Norwegian households. // 22.2.2022
Four times as many children hospitalized during Omicron COVID wave compared to Delta
The emergence of the SARS-CoV-2 Delta and Omicron variants caused severe disease and hospitalizations among children and adolescents. // 20.2.2022
The relative contagiousness of the Alpha, Delta, and Omicron SARS-CoV-2 variants
A new study, available on the arXiv* server, proposes a simple dynamic model for estimating the relative contagiousness of two variants of SARS-CoV-2, namely Alpha and Delta. Furthermore, it demonstrates how to compute the effective reproduction number for a new variant without contemporaneous sequencing results. This is important to assess the state of the pandemic in real-time. // 20.2.2022
Gradual decline in pathogenicity and enhanced cytokine induction in SARS-CoV-2 variants
A new study focuses on understanding the factors associated with the ability of the Omicron variant to infect a wide range of age groups. // 20.2.2022
Study finds antigenic profile of Omicron RBD is distinct from the prior SARS-CoV-2 variants of concern
A new study aimed to clarify whether extensive RBD mutations could affect the magnitude and immunodominance hierarchy of the host antibody response. // 18.2.2022
Faster transmission of SARS-CoV-2 Delta variant in households compared to Alpha
Researchers assess how fast the SARS-CoV-2 Alpha and Delta variants transmit from transmission data in a household study. // 17.2.2022
Study explores the high viral loads of SARS-CoV-2 Delta and Alpha variants
In a new study, scientists evaluated the cycle threshold values from 1,297 COVID-19-positive saliva samples obtained at a testing lab in the USA. // 17.2.2022
First cases of co-infection with Delta and Omicron identified during local co-circulation of both SARS-CoV-2 lineages
Researchers revealed the co-infection of the SARS-CoV-2 Delta and Omicron variants in two epidemiologically unrelated patients suffering from chronic kidney disease and requiring hemodialysis // 17.2.2022
Research identifies differences between Omicron lineages BA.1 and BA.2
Researchers recently identified another Omicron lineage, called BA.2, that is more contagious than BA.1, the Omicron lineage that sparked the winter surge of coronavirus cases in January 2022. // 16.2.2022
Characterization of SARS-CoV-2 variants in unvaccinated and vaccinated U.S. military
Researchers discuss the genomic and virological characterization of SARS-CoV-2 variants among unvaccinated and vaccinated U.S military personnel. // 16.2.2022
SARS-CoV-2 variants are evolving increased infectivity and antibody escape, studies say
First announced by the World Health Organization on Nov. 26, 2021, the SARS-CoV-2 omicron variant spread rapidly around the world, becoming the dominant variant in the U.S. and elsewhere. // 16.2.2022
Virological characteristics of SARS-CoV-2 BA.2 variant
Soon after the emergence and global spread of a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron lineage, BA.1, another Omicron lineage, BA.2, has initiated outcompeting BA.1. Statistical analysis shows that the effective reproduction number of BA.2 is 1.4-fold higher than that of BA.1. // 15.2.2022
Study compares the neutralizing potential of antibodies against two Omicron variants
A new study investigates if the two SARS-CoV-2 Omicron variants BA.1 and BA.2 are comparable with respect to their ability to evade the host immunity induced by vaccination or prior infection. // 9.1.2022
Protection of COVID-19 vaccination and previous infection against Omicron BA.1 and Delta SARS-CoV-2 infections, the Netherlands, 22 November 2021- 19 January 2022
Given the emergence of the SARS-CoV-2 Omicron BA.1 variant and the roll-out of booster COVID-19 vaccination, evidence is needed on protection conferred by primary vaccination, booster vaccination and previous SARS-CoV-2 infection against Omicron BA.1 compared with Delta infection. // 7.2.2022
Transmission dynamics of Omicron SARS-CoV-2 variant in England during January 2022
Researchers utilized data from the recent rounds of the REACT-1 study to document the transmission dynamics of SARS-CoV-2, mainly focusing on the Omicron variant in England during January 2022. // 8.2.2022
Study identifies lower viral load in the nasopharyngeal samples of patients infected with SARS-CoV-2 Omicron variant
In a new study, researchers determined if the higher transmission rate of the SARS-CoV-2 Omicron variant is due to a higher viral load compared to the Delta variant. // 8.2.2022
Characterization of the severity of Omicron relative to Delta in England
Researchers assessed the relative risks of hospitalization and death by SARS-CoV-2 Omicron variant compared to those by Delta (B.1.617.2). // 8.2.2022