Effect of Covid-19 Vaccines Against Delta Variant. A Review Article
Mohamed Raslan2, Eslam MS2, Sara AR2 and Nagwa A Sabri1*
1Department of Clinical Pharmacy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
2Drug Research Centre, Cairo, Egypt
*Corresponding Author: Nagwa A Sabri, Department of Clinical Pharmacy, Faculty of Pharmacy- Ain Shams University, Cairo, Egypt.
December 06, 2021; Published: January 10, 2022
Background: Coronavirus Disease-2019 is a novel coronavirus strain that is producing an infection that is quickly spreading over the world. Several waves of the disease occurred and different variants were discovered.
Aim: To investigate the potential threat of emerging COVID-19 new delta variants, and their effect on vaccination efficacy, hospitalization rates, and mortality rates.
Discussion: Studies indicated covid-19 patients infected with the delta strain were more likely to be hospitalized or seek emergency treatment than those infected with the alpha type. According to the findings, outbreaks of the delta variation among unvaccinated populations may exert a greater pressure on health-care systems than epidemics of the alpha type. Furthermore, it was estimate that the hazard of death related to B.1.1.7 variant infection is 6% greater than with pre-existing variants. Besides, the B.1.1.7 type is not only more contagious than pre-existing covid-19 strains, but it may also cause more severe illness. More research findings indicated that the chances of vaccine infection breakthrough were much higher in delta variant infections compared to alpha strain cases, suggesting that mRNA vaccines were less effective in preventing infection with the delta type.
Conclusion: It can be concluded that the delta variation (B.1.617.2) impairs the efficacy of critical therapeutic monoclonal antibodies for COVID-19, raises the absolute risk of death, particularly in the elderly, reduces immunization efficacy, and increases the likelihood of hospitalization.
Keywords: COVID-19; Delta Variant; Alpha Variant; B.1.617.2; Bnt162b2 Vaccine; Chadox1 Ncov-19 Vaccine
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