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Interpreting the Omicron drama


Affiliations
1 formerly at Department of Clinical Virology, Christian Medical College, Vellore 632 002, India, India
2 Thirumalai Mission Hospital, Ranipet 632 404, India, India
3 Apollo Hospitals, Navi Mumbai 400 614, India, India
 

Omicron variant of SARS-CoV-2 emerged in southern Africa in November 2021, showing more mutations on the spike protein gene than other variants, high efficiency in transmission, immune evasion, causing a mild disease, mostly upper respiratory and low mortality. Its proximate parent is unknown. We argue that its evolutionary pathway was reverse zoonosis in rodents, acquiring rodent adaptation mutations and subsequently infecting humans as zoonosis – conceptually a ‘deviant’ with antigenic shift rather than variant with antigenic drift; its pathogenesis is modified by its cell entry pathway resulting in the absence of syncytia, low virus load, sparing lungs of pneumonia and hypoxia

Keywords

Omicron variant of concern, reverse zoonosis, SARS-CoV-2.
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  • Interpreting the Omicron drama

Abstract Views: 257  |  PDF Views: 111

Authors

T. Jacob John
formerly at Department of Clinical Virology, Christian Medical College, Vellore 632 002, India, India
Mandalam S. Seshadri
Thirumalai Mission Hospital, Ranipet 632 404, India, India
Dhanya Dharmapalan
Apollo Hospitals, Navi Mumbai 400 614, India, India

Abstract


Omicron variant of SARS-CoV-2 emerged in southern Africa in November 2021, showing more mutations on the spike protein gene than other variants, high efficiency in transmission, immune evasion, causing a mild disease, mostly upper respiratory and low mortality. Its proximate parent is unknown. We argue that its evolutionary pathway was reverse zoonosis in rodents, acquiring rodent adaptation mutations and subsequently infecting humans as zoonosis – conceptually a ‘deviant’ with antigenic shift rather than variant with antigenic drift; its pathogenesis is modified by its cell entry pathway resulting in the absence of syncytia, low virus load, sparing lungs of pneumonia and hypoxia

Keywords


Omicron variant of concern, reverse zoonosis, SARS-CoV-2.

References





DOI: https://doi.org/10.18520/cs%2Fv124%2Fi8%2F893-898