Omicron and vaccine booster dose – an update





COVID19, Omicron, Third Dose, Variant of Concern

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Review Article


  • Pushpa Nagavalli Basavanna JSS Medical College, JSS Academy Of Higher Education And Research, Mysore, Karnataka
  • Hatur Basavanagowdappa JSS Medical College, JSS Academy Of Higher Education And Research, Mysore, Karnataka
  • Archana Siddaiah St.John’s National Academy of Health sciences, Bangalore
  • Apurba Patra All India Institute of Medical Sciences, Bathinda
  • Viveka Srinivasan Azeezia Institute of Medical Sciences and Research, Kollam
  • Sudha Makam Janardhan HELYXON Health care Solutions Pvt Limited, Chennai
  • Rachna Pasi All India Institute of Medical Sciences, Mangalagiri;
  • Kumar Satish Ravi All India Institute of Medical Sciences, Rishikesh


Mutations in coronavirus is not unheard off. The variant, Omicron B.1.1.529 has overall 50 mutations and is considered as a variant of concern. Though the new variant has shown changes throughout its genome, S gene changes predominate. Significant changes in the S encoding gene, S gene, influences not only the transmissibility properties of SARS-CoV-2 but also the efficacy of existing vaccines. Increased transmissibility and ability of this variant to evade host immune responses conferred either due to past infections or due to vaccination driving increase in number of infections. However, the severity of the infections is low in comparison to its predecessors. A meta-analysis of ten studies analyzing the effect of COVID-19 vaccine booster dose, it was found studies report 10-to-42-fold increase in omicron neutralization. COVID appropriate behaviors, if followed rigidly can bring a meaningful change in the viral spread and resultant health impacts.

How to Cite

Basavanna PN, Basavanagowdappa H, Siddaiah A, Patra A, Srinivasan V, Janardhan SM, Pasi R, Ravi KS. Omicron and vaccine booster dose – an update. Indian J Community Health [Internet]. 2022 Jun. 30 [cited 2022 Aug. 16];34(2):167-9. Available from:


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