The World Health Organization (WHO) Friday declared B.1.1.529, a “variant of concern” while giving it the new name “Omicron,” because of its unusual mutation
WHO said a“Preliminary evidence suggests an increased risk of reinfection with this virus strain, as compared to others” and scholars have warned that the new coronavirus has the makings of a “super-contagious” virus.
The Omicron, or B.1.1.529, has a whopping 32 mutations of the spike protein, raising fears that it will be resistant to existing vaccines.
Following this, authorities across the world have classed the Omicron strain as a “high to very high” risk Covid-19 variant. For example, the European Center for Disease Prevention and Control (ECDC) warned there was still “considerable uncertainty related to the transmissibility, vaccine effectiveness, risk for reinfections and other properties of the Omicron variant.”
IT News Nigeria gathered that the large number of mutations have also prompted fears that Omicron could be resistant to existing vaccines and therapeutics, especially as currently available immunizations have been seen to lose effectiveness over time against other known variants of concern.
One major determining factor in the transmissibility of the virus is the evolution of its “spike proteins” – microscopic protrusions that allow the coronavirus to access and hijack host cells, causing infection. A strain detected in South Africa in May 2020 and dubbed ‘Beta,’ for example, had three significant mutations in its spike region, which helped make it between 20 and 30% more infectious. Omicron, on the other hand, is thought to have at least 32 spike mutations.
What WHO says and all you need to know about Omicron
The Technical Advisory Group on SARS-CoV-2 Virus Evolution (TAG-VE) is an independent group of experts that periodically monitors and evaluates the evolution of SARS-CoV-2 and assesses if specific mutations and combinations of mutations alter the behaviour of the virus. The TAG-VE was convened on 26 November 2021 to assess the SARS-CoV-2 variant: B.1.1.529.
The B.1.1.529 variant was first reported to WHO from South Africa on 24 November 2021. The epidemiological situation in South Africa has been characterized by three distinct peaks in reported cases, the latest of which was predominantly the Delta variant. In recent weeks, infections have increased steeply, coinciding with the detection of B.1.1.529 variant. The first known confirmed B.1.1.529 infection was from a specimen collected on 9 November 2021.
This variant has a large number of mutations, some of which are concerning. Preliminary evidence suggests an increased risk of reinfection with this variant, as compared to other VOCs. The number of cases of this variant appears to be increasing in almost all provinces in South Africa. Current SARS-CoV-2 PCR diagnostics continue to detect this variant. Several labs have indicated that for one widely used PCR test, one of the three target genes is not detected (called S gene dropout or S gene target failure) and this test can therefore be used as marker for this variant, pending sequencing confirmation. Using this approach, this variant has been detected at faster rates than previous surges in infection, suggesting that this variant may have a growth advantage.
There are a number of studies underway and the TAG-VE will continue to evaluate this variant. WHO will communicate new findings with Member States and to the public as needed.
Based on the evidence presented indicative of a detrimental change in COVID-19 epidemiology, the TAG-VE has advised WHO that this variant should be designated as a VOC, and the WHO has designated B.1.1.529 as a VOC, named Omicron.
As such, countries are asked to do the following:
- enhance surveillance and sequencing efforts to better understand circulating SARS-CoV-2 variants.
- submit complete genome sequences and associated metadata to a publicly available database, such as GISAID.
- report initial cases/clusters associated with VOC infection to WHO through the IHR mechanism.
- where capacity exists and in coordination with the international community, perform field investigations and laboratory assessments to improve understanding of the potential impacts of the VOC on COVID-19 epidemiology, severity, effectiveness of public health and social measures, diagnostic methods, immune responses, antibody neutralization, or other relevant characteristics.
Individuals are reminded to take measures to reduce their risk of COVID-19, including proven public health and social measures such as wearing well-fitting masks, hand hygiene, physical distancing, improving ventilation of indoor spaces, avoiding crowded spaces, and getting vaccinated.
For reference, WHO has working definitions for SARS-CoV-2 Variant of Interest (VOI) and Variant of Concern (VOC).
A SARS-CoV-2 VOI is a SARS-CoV-2 variant:
- with genetic changes that are predicted or known to affect virus characteristics such as transmissibility, disease severity, immune escape, diagnostic or therapeutic escape; AND
- that has been identified as causing significant community transmission or multiple COVID-19 clusters, in multiple countries with increasing relative prevalence alongside increasing number of cases over time, or other apparent epidemiological impacts to suggest an emerging risk to global public health.
A SARS-CoV-2 VOC is a SARS-CoV-2 variant that meets the definition of a VOI (see above) and, through a comparative assessment, has been demonstrated to be associated with one or more of the following changes at a degree of global public health significance:
- increase in transmissibility or detrimental change in COVID-19 epidemiology; OR
- increase in virulence or change in clinical disease presentation; OR
- decrease in effectiveness of public health and social measures or available diagnostics, vaccines, therapeutics