Emerging sars-cov-2 variants of concern (Vocs): An impending global crisis

Angel Yun Kuan Thye, Jodi Woan Fei Law, Priyia Pusparajah, Vengadesh Letchumanan, Kok Gan Chan, Learn Han Lee

Research output: Contribution to journalReview ArticleResearchpeer-review

90 Citations (Scopus)


The worldwide battle against the SARS-CoV-2 virus rages on, with millions infected and many innocent lives lost. The causative organism, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a beta coronavirus that belongs to the Coronaviridae family. Many clinically significant variants have emerged, as the virus’s genome is prone to various mutations, leading to antigenic drift and resulting in evasion of host immune recognition. The current variants of concern (VOCs) include B.1.1.7 (Alpha), B.1.351 (Beta), B.1.617/B.1.617.2 (Delta), and P.1 (Gamma). The emerging variants contain various important mutations on the spike protein, leading to deleterious consequences, such as immune invasion and vaccine escape. These adverse effects result in increased transmissibility, morbidity, and mortality and the evasion of detection by existing or currently available diagnostic tests, potentially delaying diagnosis and treatment. This review discusses the key mutations present in the VOC strains and provides insights into how these mutations allow for greater transmissibility and immune evasion than the progenitor strain. Continuous monitoring and surveillance of VOC strains play a vital role in preventing and controlling the virus’s spread.

Original languageEnglish
Article number1303
Number of pages26
Issue number10
Publication statusPublished - Oct 2021


  • Mutations
  • Progenitor
  • SARS-CoV-2
  • Transmissibility
  • Variant of concern (VOC)

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