Department of Physiology, University of Gour Banga, Malda, 732103, West Bengal, India.
Department of Medicine, R.G.Kar Medical College, Kolkata, 700004, West Bengal, India.
Immunol Res. 2022 Jun;70(3):289-315. doi: 10.1007/s12026-022-09265-0. Epub 2022 Feb 22.
SARS-CoV-2 is an RNA virus that was identified for the first time in December 2019 in Wuhan, China. The World Health Organization (WHO) labeled the novel coronavirus (COVID-19) outbreak a worldwide pandemic on March 11, 2020, due to its widespread infectivity pattern. Because of the catastrophic COVID-19 outbreak, the development of safe and efficient vaccinations has become a key priority in every health sector throughout the globe. On the 13th of January 2021, the vaccination campaign against SARS-CoV-2 was launched in India and started the administration of two types of vaccines known as Covaxin and Covishield. Covishield is an adenovirus vector-based vaccine, and Covaxin was developed by a traditional method of vaccine formulation, which is composed of adjuvanted inactivated viral particles. Each vaccine's utility or efficiency is determined by its formulation, adjuvants, and mode of action. The efficacy of the vaccination depends on numeral properties like generation antibodies, memory cells, and cell-mediated immunity. According to the third-phase experiment, Covishield showed effectiveness of nearly 90%, whereas Covaxin has an effectiveness of about 80%. Both vaccination formulations in India have so far demonstrated satisfactory efficacy against numerous mutant variants of SARS-CoV-2. The efficacy of Covishield may be diminished if the structure of spike (S) protein changes dramatically in the future. In this situation, Covaxin might be still effective for such variants owing to its ability to produce multiple antibodies against various epitopes. This study reviews the comparative immunogenic and therapeutic efficacy of Covaxin and Covishield and also discussed the probable vaccination challenges in upcoming days.
SARS-CoV-2 是一种 RNA 病毒，于 2019 年 12 月在中国武汉首次被发现。世界卫生组织（WHO）于 2020 年 3 月 11 日将新型冠状病毒（COVID-19）爆发标记为全球大流行，因其广泛的传染性模式。由于 COVID-19 爆发的灾难性影响，开发安全有效的疫苗已成为全球每个卫生部门的首要重点。2021 年 1 月 13 日，印度开始接种针对 SARS-CoV-2 的疫苗，并开始接种两种疫苗，即 Covaxin 和 Covishield。Covishield 是一种基于腺病毒载体的疫苗，而 Covaxin 是通过传统的疫苗配方开发的，由佐剂灭活病毒颗粒组成。每种疫苗的效用或效率取决于其配方、佐剂和作用方式。疫苗接种的效果取决于产生抗体、记忆细胞和细胞介导免疫等数量特性。根据第三阶段的实验，Covishield 的有效性接近 90%，而 Covaxin 的有效性约为 80%。到目前为止，印度的这两种疫苗接种方案对 SARS-CoV-2 的多种突变变体都表现出令人满意的效果。如果未来刺突（S）蛋白的结构发生巨大变化，Covishield 的效果可能会降低。在这种情况下，由于 Covaxin 能够针对各种表位产生多种抗体，因此它可能仍然对这些变体有效。本研究综述了 Covaxin 和 Covishield 的免疫原性和治疗效果比较，并讨论了未来几天可能出现的疫苗接种挑战。
