SARS-COV-2 omicron variant o updated Dec 2021 William Hu Grade 12, University of Toronto Schools, SLAP COVID 19 Research Program , Toronto, ON, Canada Dec 23,2021

Since November, 2021, the SARS-COV-2 omicron variant has spread across the globe. This variant as several differences compared to other SARS-COV-2 strains. Genetically, Omicron has 60 mutations compared to the original strain, 58 of which cause phenotypic differences. In its proteome, the variant has 30 amino acid changes, 3 deletions and 1 insertion in the Spike protein. Omicron infects faster than the Delta and Original variants due to more rapid multiplication. However, Omicron has less severe symptoms because it does not enter the lower lungs. Researchers compared lung tissue from Omicron and sARS-COV-2 patients. They found Omicron replicates 70 times faster than Delta and original SARS-COV-2 over 24 hrs, but 10 times less efficiently in lung tissue compared to original SARS-COV-2. However, scientists warn that immune response, as well as disease severity, affects health outcomes. Even if Omicron is less deadly, the fact that it infects so many people can cause more severity. Furthermore, Omicron is a different evolutionary strain of SARS-COV-2 compared to Delta. UK has suffered 10,000 cases, 10 people hospitalized and 1 died. Ontario reported 5790 cases on Dec 23,2021,and will be 10,000 cases on the end of 2021.Omicron could become an upper respiratory infection, more similar to the common cold or pneumonia. Omicron infect faster because it infects bronchial tissue and not lungs. Furthermore, Omicron has demonstrated a fast spread from its first plane passenger in South Africa (first case Nov.11) to the UK, Canada and the US. As of Dec. 2021, it has spread to over 80 countries. Omicron poses a problem because two doses may not provide total protection against the virus, although 3 doses may provide stringer immunity. Although the variant seems less pathogenic than previous strains, it is still too early to confirm and caution must be taken without assuming omicron will be less harmful.