Frontiers | Evolution of SARS-CoV-2: impact of variants on hosts, COVID-19 vaccines and countermeasures

ORIGINAL RESEARCH

9 September 2022

Mutations in SARS-CoV-2 nucleocapsid in variants of concern impair the sensitivity of SARS-CoV-2 detection by rapid antigen tests

Ibrahim T. Hagag, 4 more and Markus Keller

7,080 views

13 citations

GENERAL COMMENTARY

11 October 2022

Commentary: MSH3 homology and potential recombination link to SARS-CoV-2 furin cleavage site

Yseulys Dubuyand Hugo Lachuer

9,003 views

4 citations

ORIGINAL RESEARCH

19 October 2022

Neutralizing antibodies from the rare convalescent donors elicited antibody-dependent enhancement of SARS-CoV-2 variants infection

Song Mu, 13 more and Aishun Jin

3,032 views

13 citations

BRIEF RESEARCH REPORT

23 September 2022

Assessing the impact of the four COVID-19 variants and the vaccine coverage on mortality in Malta over 2 years: An observational case study

Sarah Cuschieri, 1 more and Victor Grech

2,532 views

1 citations

SARS-CoV-2 and the Missing Link of Intermediate Hosts in Viral Emergence - What We Can Learn From Other Betacoronaviruses

REVIEW

7 July 2022

SARS-CoV-2 and the Missing Link of Intermediate Hosts in Viral Emergence - What We Can Learn From Other Betacoronaviruses

Brayden G. Schindell, 3 more and Jason Kindrachuk

27,650 views

22 citations

ORIGINAL RESEARCH

4 July 2022

Spike Mutation Profiles Associated With SARS-CoV-2 Breakthrough Infections in Delta Emerging and Predominant Time Periods in British Columbia, Canada

Chad D. Fibke, 7 more and Hind Sbihi

4,104 views

9 citations

Changes in Symptoms Experienced by SARS-CoV-2-Infected Individuals – From the First Wave to the Omicron Variant

ORIGINAL RESEARCH

1 July 2022

Changes in Symptoms Experienced by SARS-CoV-2-Infected Individuals – From the First Wave to the Omicron Variant

Hansjörg Schulzeand Wibke Bayer

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic and public health crisis since the beginning of 2020. First recognized for the induction of severe disease, the virus also causes asymptomatic infections or infections with mild symptoms that can resemble common colds. To provide better understanding of these mild SARS-CoV-2 infections and to monitor the development of symptoms over time, we performed a detailed analysis of self-reported symptoms of SARS-CoV-2 positive and SARS-CoV-2 negative individuals. In an online-based survey, a total of 2117 individuals provided information on symptoms associated with an acute respiratory infection, 1925 of the participants had tested positive for SARS-CoV-2 infection, and 192 had tested negative. The symptoms reported most frequently during the early phases of the pandemic by SARS-CoV-2 infected individuals were tiredness, headache, impairment of smell or taste and dry cough. With the spread of the alpha and delta variants, the frequency of nose symptoms such as blocked or runny nose and sneezing increased to being reported by almost 60% of infected individuals. Interestingly, the spread of the omicron variant brought a sharp decrease in the incidence of impaired sense of smell or taste, which was reported by only 24% in this phase of the pandemic. The constellation of symptoms should be monitored closely in the months ahead, since future SARS-CoV-2 variants are likely to bring about more changes.

9,007 views

40 citations

BRIEF RESEARCH REPORT

24 June 2022

SARS-CoV-2 Genomic Surveillance Enables the Identification of Delta/Omicron Co-Infections in Argentina

María Belén Pisano, 9 more and Viviana E. Ré

2,907 views

12 citations

REVIEW

6 May 2022

Alpha, Beta, Delta, Omicron, and SARS-CoV-2 Breakthrough Cases: Defining Immunological Mechanisms for Vaccine Waning and Vaccine-Variant Mismatch

Benjamin Hewins, 9 more and David J. Kelvin

The COVID-19 pandemic, caused by the SARS-CoV-2 coronavirus, is responsible for over 400 million cases and over 5.5 million deaths worldwide. In response to widespread SARS-CoV-2 infection, immunization of the global population has approached 60% one dose and 54% full dose vaccination status. Emerging data indicates decreasing circulating antibody levels as well as decreases in other immune correlates in vaccinated individuals. Complicating the determination of vaccine effectiveness is the concomitant emergence of novel SARS-CoV-2 variants with substantial antigenic differences from the ancestral D614G strain. The Omicron variant (B.1.1.529) spike protein has over 30 mutations compared with the D614G spike protein, which was used to design most SARS-CoV-2 vaccines in use today. Therefore, breakthrough cases of SARS-CoV-2 infections or severe disease in fully vaccinated individuals must be interpreted with caution taking into consideration vaccine waning and the degree of vaccine variant-mismatch resulting in adaptive immune evasion by novel emerging SARS-CoV-2 variants.

9,976 views

20 citations

ORIGINAL RESEARCH

3 June 2022

Booster Vaccination Strategies for “Living With COVID-19”

Jung Eun Kim, 1 more and Hee-Sung Kim

2,648 views

6 citations

PERSPECTIVE

15 December 2021

Saliva for COVID-19 Testing: Simple but Useless or an Undervalued Resource?

Sara Pijuan-Galito, 31 more and Chris Denning

During the COVID-19 pandemic, countries with robust population-based asymptomatic testing were generally successful in controlling virus spread, hence reducing hospitalisations and deaths. This effectiveness inspired widespread asymptomatic surveillance for COVID-19/SARS-CoV-2 globally. Polarised vaccination programmes coupled with the relatively short-lived immunity vaccines provide mean that reciprocal cross-border exchanges of each new variant is likely, as evidenced by Delta and Gamma, and asymptomatic testing will be required for the foreseeable future. Reliance on nasopharyngeal swabs is contributing to ‘testing fatigue’ arising due to difficulties in standardising administration, unpleasantness and inappropriateness of use in younger people or individuals with special needs. There has also been erosion in confidence of testing due to variable and/or poor accuracy of lateral flow devices to detect COVID-19. Here, we question why saliva-based PCR assays are not being used more widely, given that standardisation is easy and this non-invasive test is suitable for everyone, providing high sensitivity and accuracy. We reflect on our experience with the University of Nottingham COVID-19 Asymptomatic Testing, where (as of October 2021) 96,317 samples have been processed by RT-qPCR from 23,740 repeat saliva donors, yielding 465 positive cases. We challenge myths that saliva is difficult to process, concluding it is an undervalued resource for both asymptomatic and symptomatic detection of SARS-CoV-2 genomes to an accuracy of >99% and a sensitivity of 1-10 viral copies/ml. In July 2021, our data enabled Nottingham to become the first UK University to gain recommended for accreditation and the first UK institute to gain this accolade for saliva.

Saliva for COVID-19 Testing: Simple but Useless or an Undervalued Resource?

15,613 views

16 citations

Impact