American Journal of Microbiological Research
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American Journal of Microbiological Research. 2021, 9(4), 103-106
DOI: 10.12691/ajmr-9-4-1
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Efficacy of the Vaccines, Their Safety, and Immune Responses against SARS-CoV-2 Infections

Mahendra Pal1, and Kirubel Paulos Gutama2

1Narayan Consultancy on Veterinary Public Health and Microbiology, Anand, India

2Adaba Woreda Livestock and Fishery Resource Development Office, West Arsi, Ethiopia

Pub. Date: October 12, 2021

Cite this paper:
Mahendra Pal and Kirubel Paulos Gutama. Efficacy of the Vaccines, Their Safety, and Immune Responses against SARS-CoV-2 Infections. American Journal of Microbiological Research. 2021; 9(4):103-106. doi: 10.12691/ajmr-9-4-1


The search for vaccines has been a high priority since the worldwide COVID-19 pandemic was declared. Currently, mRNA-based vaccines, adenovirus-based vaccines, inactivated virus vaccines, and other vaccine platforms are all employed to combat the SARS-CoV-2 virus. BNT162b2 and mRNA-1273 are mRNA-based vaccines. The vaccination appears to be effective against SARS-CoV-2 strains that have emerged since the first study. They have primarily minor side effects, and there are no major safety concerns. Adenovirus-based vaccines are delivered by genetic cargo that is based on non-replicating adenovirus vectors that can increase immune response without the need of adjuvants. This is the case for Ad26.CoV2.S, ChAdOx1 nCoV-19/AZD1222, Gam-COVID-Vac/Sputnik V andAd5-based COVID-19 vaccine. There have been no known incidences of allergy to adenovirus vaccines, unlike mRNA vaccines. Inactivated virus vaccines are a common form of vaccine that has been used for decades. The goal is to render the virus non-infectious while preserving immunogenicity with high-quality antigens in order to trigger an immune response. The researched formaldehyde-inactivated whole-virus SARS-CoV2 vaccine (CoronaVac), as well as WIV04 and HB02, utilize this sort of vaccine formulation. A recombinant protein nanoparticle vaccine named NVX-CoV2373 is made up of trimeric spike glycoproteins with a potent Matrix-M1 adjuvant. Against the variant B.1.1.7 (Alpha), the vaccine appeared to be very effective. Vaccine efficacy against the B.1.351 (Beta) strain, on the other hand, proved to be lower.

COVID-19 efficacy immune response safety vaccines

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