Samer Shamshad¹, Sanchita Srivastava² and Senthilkumar Rajagopal³*

¹The Department of Bacteriology, ICAR - National Institute of Veterinary Epidemiology and Disease Informatics, Bengaluru, KA, India

*Corresponding Author: Senthilkmar Rajagopal, Associate Professor, Department of Biotechnology, School of Applied Sciences, REVA University, Bengaluru, KA, India.

Received: July 26, 2022; Published: August 17, 2022

Abstract

The ongoing Covid-19 pandemic has grappled the world with fear, infecting around 18.2 Cr people and resulting in the deaths of 39.5 L in the span of a mere eighteen months (until July 2021). First identified as the cause of a cluster of pneumonia cases in Wuhan, China in 2019, Covid-19 is now proving to be a complex and long-lasting challenge for everyone. Just as any other virus, SARS-CoV-2 also mutates all the time, it has been acquiring minor random mutations ever since it jumped from animal (bat) to humans. These constant mutations are creating new variants and are posing a challenge to scientific efforts all over the globe. The aftermath is especially felt in the United Kingdom (with the B.1.1.7 variant), India (B.1.617), and Brazil (P1). Despite the extraordinary speed of vaccination and other drug discoveries against the novel corona virus, these variants continue to threaten mass destruction. This article describes SARS-CoV-2, its dominant variants (α, β, γ), associated mortality rate, epidemic, and prevalence factor, how immune system reacted to different variants and the current treatment available.

Keywords: Epidemic; Immune Evasion; SARS-CoV-2; Dominant Variants; Spike Protein; and Variant of Concern

References

1. Hamre D and Procknow JJ. “A new virus isolated from the human respiratory tract”. Proceedings of the Society for Experimental Biology and Medicine 121 (1966): 190-193.
2. McIntosh K., et al. “Recovery in tracheal organ cultures of novel viruses from patients with respiratory disease”. Proceedings of the National Academy of Sciences of the United States of America 57 (1967): 933-940.
3. Van Der Most RG., et al. “Homologous RNA recombination allows efficient introduction of site- specific mutations into the genome of coronavirus mhv-a59 via synthetic co-replicating RNAs”. Nucleic Acids Research 20 (1992): 3375-3381.
4. Ghosh PK. “Global efforts on vaccines development against SARS-CoV-2 and Indian endeavor”. MGM Journal of Medical Sciences 8 (2021): 422-434.
5. Public Health England (2021): 16 and 22.
6. “SARS-CoV-2 variants of concern and variants under investigation in England, technical briefing 14”. Public Health England (2021): GOV-8530.
7. Pearson H., et al. “AHS breaks down vaccination data of COVID-19 Delta variant outbreak at Calgary hospital”. Global News (2021).
8. “SARS-CoV-2 variants of concern”. ECDC.eu. European Centre for Disease Prevention and Control (2021).
9. “SARS-CoV-2 variants of concern and variants under investigation in England Technical Briefing 21”. Public Health England (2021): 16-22.
10. Nyberg T., et al. “Risk of hospital admission for patients with SARS-CoV-2 variant B.1.1.7: Cohort Anal”. BMJ 373 (2021): 1412.
11. “SARS-CoV-2 Variant Classifications and Definitions”. CDC.gov. Centers for Disease Control and Prevention (2020).
12. World Health Organization (2021).
13. Faria NR., et al. “Genomics and epidemiology of the P.1 SARS-CoV-2 lineage in Manaus, Brazil”. Science PMC (2021) 8139423.
14. Andreoni M., et al. “Brazil's Covid Crisis Is a Warning to the Whole World, Scientists Say - Brazil is seeing a record number of deaths, and the spread of a more contagious coronavirus variant that may cause reinfection”. The New York Times (2021).
15. Zimmer C. “Virus Variant in Brazil Infected Many Who Had Already Recovered from Covid-19”. The New York Times. (2021)
16. Yadav PD., et al. “Isolation and characterization of VUI-202012/01, a SARS-CoV-2 variant in travelers from the United Kingdom to India”. Journal of Travel Medicine 28-2 (2021): 9-11.
17. Pragya DY. “Imported SARS-CoV-2 V501Y.V2 variant (B.1.351) detected in travelers from South Africa and Tanzania to India”. Travel Medicine and Infectious Disease (2021): 102023.
18. “Lineage B.1.1.529”. PANGOLIN (2021).
19. McGregor G. “What is stealth Omicron? The rise of the subvariant is alarming some scientists who say it needs its own Greek letter”. Fortune (2022).
20. “A subvariant of Omicron, BA.2., now comprises almost half of all Danish Omicron cases”. Statens Serum Institute (2022).
21. Aleem A., et al. “Emerging Variants of SARS-CoV-2 And Novel Therapeutics Against Coronavirus (COVID-19)”. In: StatPearls. Treasure Island (FL) (2022).
22. V’kovski P., et al. “Coronavirus biology and replication: implications for SARS-CoV-2”. Nature Reviews 020 (2021): 00468-6.
23. Brian Doctrow. “How COVID-19 variants evade immune response. NIH Research matters-Short Communication”. U.S. Department of Health and Human Services National Institutes of Health- (NIH) research matters (2021).
24. Colin D Funk. “A Snapshot of the Global Race for Vaccines Targeting SARS-CoV-2 and the COVID-19 Pandemic”. Frontiers in Pharmacology (2020): 11-937.
25. Samudrala PK., et al. “Virology, pathogenesis, diagnosis and in-line treatment of COVID-19”. European Journal of Pharmacology883 (2020): 173375.
26. Ghosh PK. “Global efforts on vaccines development against SARS-CoV-2 and Indian endeavor”. MGM Journal of Medical Sciences 8 (2021): 422-434.
27. Eastman RT., et al. “Remdesivir: A Review of Its Discovery and Development Leading to Emergency Use Authorization for Treatment of COVID-19”. ACS Central Science 6 (2020): 672-683.
28. Jia Liu., et al. “Hydroxychloroquine, a less toxic derivative of chloroquine, is effective in inhibiting SARS-CoV-2 infection in vitro”. Cell Discovery 6 (2020): 16.
29. Vincent MJ, et al. “Chloroquine is a potent inhibitor of SARS coronavirus infection and spread”. Virology Journal 2 (2005): 69.
30. Di Nicolantonio JJ., et al. “Ivermectin may be a clinically useful anti-inflammatory agent for late-stage COVID-19”. Open Heart (2020): 001350.
31. Meng Y, et al. “Structural and functional ramifications of antigenic drift in recent SARS-CoV-2 variants”. Science (2021).

Citation

Citation: Senthilkumar Rajagopal., et al. “A Recent Epidemiological Condition of Covid-19 Pandemic: A Review". Acta Scientific Microbiology 5.9 (2022): 99-107.

Copyright

Copyright: © 2022 Senthilkumar Rajagopal., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.