Coronaviruses use a very diverse range of receptors SARS-CoV (which causes SARS) and SARS-CoV-2 (which causes COVID-19) both interact with angiotensin-converting enzyme 2 (ACE2). The S1 region contains the receptor-binding domain that binds to receptors on the cell surface. Spike glycoprotein is a class I fusion protein that contains two regions, known as S1 and S2, responsible for these two functions. The function of the spike glycoprotein is to mediate viral entry into the host cell by first interacting with molecules on the exterior cell surface and then fusing the viral and cellular membranes. The distinctive appearance of these spikes when visualized using negative stain transmission electron microscopy, "recalling the solar corona", gives the virus family its main name. The spike protein assembles into trimers that form large structures, called spikes or peplomers, that project from the surface of the virion. Spike (S) glycoprotein (sometimes also called spike protein, formerly known as E2 ) is the largest of the four major structural proteins found in coronaviruses. īetacoronavirus spike glycoprotein S1, receptor bindingīetacoronavirus-like spike glycoprotein S1, N-terminal Africa CDC: Dr Sofonias Kifle Tessema ( KRISP: Prof.Model of the external structure of the SARS-CoV-2 virion.lineage is available the COVID-10 Genomics UK Consortium Website ( ) and on website ( ) A simple Question and Answer section produced by the South Africa Department of Health is also available at ( ).Salim Abdool Karim on what we know, what we do not know and what does mean for the pandemic in Africa ( ). Detailed presentations on the 501Y.V2 by Prof.Specimens of suspected cases should be stored for further sequencing and investigation. Carefully follow-up cases with S-gene drop-out during RT-PCR tests and suspected COVID-19 reinfection.Notify Africa CDC immediately if they identify any new SARS-CoV-2 variant.Africa CDC Institute of Pathogen Genomics, through the Africa Pathogen Genomics Initiative, will support coordination at the continental level. Collaborate and coordinate with national or regional pathogen genomics laboratories to expand genomic surveillance and sequence virus isolates in a timely manner.Enhance epidemiologic surveillance for early identification of hotspots and continue to encourage community members to adhere to the non-pharmaceutical interventions (the public health and social measures).Step up testing, contact tracing and case management.Given that there is currently a lack of evidence to indicate the extent to which these new 501Y lineages are spread outside of South Africa or outside Europe, timely efforts to monitor, prevent and control its spread are needed, and include the following:Īfrica CDC advise Member States and health authorities to: While research is ongoing to generate clear-cut evidence, these two lineages seem to spread faster, and this notification is being sent out to increase Member State awareness of the new variants from South Africa and the UK, which may spread and introduced to other Member States. Preliminary analysis in South Africa (501Y.V2) and the UK (501Y) suggests that this variant is significantly more transmissible than previously circulating variants and potentially higher viral load in South Africa. Further studies are ongoing to determine whether this lineage is more infectious and transmissible or causes more severe illness or evade the vaccination or a human immune response.Īs of 21 December 2020, more than 300 genomes of the 501Y.V2 variant have been identified, all in South Africa. In addition, the United Kingdom has recently identified a second new lineage of SARS-CoV-2, which contain the N501Y mutation but distinct from the South African variant. One of the most significant is an N501Y mutation in the receptor binding motif that bind to the human ACE2 receptor. The new variant is defined by multiple non-synonymous mutation in the spike (S) protein, of which three are on the receptor-binding domain (RBD). Tulio de Olivera, had identified a new variant of SARS-CoV2 that is driving the second wave of infections. The Network for Genomics Surveillance in South Africa (NGS-SA), led by Prof. Over the last few weeks, South Africa has also faced a rapid increase in the number of COVID-19 cases driven by a new SARS-CoV-2 lineage, the 501Y.V2, which show signs to be potentially more transmissible. Notification*: Alert Warning Activation Executionįrom: Africa Centres for Disease Control and Prevention (Africa CDC) jointly with Africa Task Force for Coronavirus (AFTCOR)Īfrica is currently experiencing a sharp increase in the number of confirmed COVID-19 cases across Member States. Incident/Event title/Name: New SARS-CoV-2 variant with multiple spike protein mutations
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