How Omicron evades antibodies in vaccinated and unvaccinated people

How Omicron evades antibodies in vaccinated and unvaccinated people

Context: The current wave of Covid-19 highlights a high risk of reinfection by the Omicron variant of SARS-CoV-2.

Omicron Variant:

• The Omicron variant(B.1.1.529) is a variant of SARS-CoV-2 (the virus that causes COVID-19) that was first reported to the World Health Organization (WHO) from South Africa
• Omicron multiplies around 70 times faster than the Delta variant in the bronchi (lung airways) but evidence suggests it is less severe than previous strains, especially compared to the Delta variant
• Viruses like SARS-CoV-2 continuously evolve as changes in the genetic code (caused by genetic mutations or viral recombination) occur during replication of the genome

What is variant?

A variant has one or more mutations that differentiate it from other variants of the SARS-CoV-2 viruses.

Different classes of SARS-CoV-2 variants:

• Alpha (B.1.1.7 and Q lineages)
• Beta (B.1.351 and descendent lineages)
• Gamma (P.1 and descendent lineages)
• Delta (B.1.617.2 and AY lineages)
• Epsilon (B.1.427 and B.1.429)
• Eta (B.1.525)
• Iota (B.1.526)
• Kappa (B.1.617.1)
• 1.617.3
• Mu (B.1.621, B.1.621.1)
• Zeta (P.2)
• Omicron (B.1.1.529, BA.1, BA.1.1, BA.2, BA.3, BA.4 and BA.5 lineages)
• The BA.5 sub-variant has the most transmissibility and immune escape potential of any variant since the COVID-19 pandemic began
• Both BA.4 and BA.5 have their own unique mutations, including changes in the receptor-binding domain of the spike protein
• Cell culture experiments revealed that BA.4 and BA.5 replicate more efficiently in human alveolar epithelial cells than BA.2
• Both BA.4 and BA.5 have their own unique mutations, including changes in the receptor-binding domain of the spike protein

Concept:

Antibody:

An antibody is a protein component of the immune system that circulates in the blood, recognizes foreign substances like bacteria and viruses, and neutralizes them.

After exposure to a foreign substance, called an antigen, antibodies continue to circulate in the blood, providing protection against future exposures to that antigen

Antibody is a part of the host cell’s defense. It’s made by a certain type of white blood cell that’s called a B cell